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Discovery of Terminal Oxazole-Bearing Natural Products by a Targeted Metabologenomic Approach. Angew Chem Int Ed Engl 2024; 63:e202402465. [PMID: 38482567 DOI: 10.1002/anie.202402465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2024] [Indexed: 04/13/2024]
Abstract
A targeted metabologenomic method was developed to selectively discover terminal oxazole-bearing natural products from bacteria. For this, genes encoding oxazole cyclase, a key enzyme in terminal oxazole biosynthesis, were chosen as the genomic signature to screen bacterial strains that may produce oxazole-bearing compounds. Sixteen strains were identified from the screening of a bacterial DNA library (1,000 strains) using oxazole cyclase gene-targeting polymerase chain reaction (PCR) primers. The PCR amplicon sequences were subjected to phylogenetic analysis and classified into nine clades. 1H-13C coupled-HSQC NMR spectra obtained from the culture extracts of the hit strains enabled the unequivocal detection of the target compounds, including five new oxazole compounds, based on the unique 1JCH values and chemical shifts of oxazole: lenzioxazole (1) possessing an unprecedented cyclopentane, permafroxazole (2) bearing a tetraene conjugated with carboxylic acid, tenebriazine (3) incorporating two modified amino acids, and methyl-oxazolomycins A and B (4 and 5). Tenebriazine displayed inhibitory activity against pathogenic fungi, whereas methyl-oxazolomycins A and B (4 and 5) selectively showed anti-proliferative activity against estrogen receptor-positive breast cancer cells. This metabologenomic method enables the logical and efficient discovery of new microbial natural products with a target structural motif without the need for isotopic labeling.
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Observation of WWγ Production and Search for Hγ Production in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2024; 132:121901. [PMID: 38579207 DOI: 10.1103/physrevlett.132.121901] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Accepted: 01/31/2024] [Indexed: 04/07/2024]
Abstract
The observation of WWγ production in proton-proton collisions at a center-of-mass energy of 13 TeV with an integrated luminosity of 138 fb^{-1} is presented. The observed (expected) significance is 5.6 (5.1) standard deviations. Events are selected by requiring exactly two leptons (one electron and one muon) of opposite charge, moderate missing transverse momentum, and a photon. The measured fiducial cross section for WWγ is 5.9±0.8(stat)±0.8(syst)±0.7(modeling) fb, in agreement with the next-to-leading order quantum chromodynamics prediction. The analysis is extended with a search for the associated production of the Higgs boson and a photon, which is generated by a coupling of the Higgs boson to light quarks. The result is used to constrain the Higgs boson couplings to light quarks.
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New Structures in the J/ψJ/ψ Mass Spectrum in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2024; 132:111901. [PMID: 38563916 DOI: 10.1103/physrevlett.132.111901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 12/07/2023] [Accepted: 01/31/2024] [Indexed: 04/04/2024]
Abstract
A search is reported for near-threshold structures in the J/ψJ/ψ invariant mass spectrum produced in proton-proton collisions at sqrt[s]=13 TeV from data collected by the CMS experiment, corresponding to an integrated luminosity of 135 fb^{-1}. Three structures are found, and a model with quantum interference among these structures provides a good description of the data. A new structure is observed with a local significance above 5 standard deviations at a mass of 6638_{-38}^{+43}(stat)_{-31}^{+16}(syst) MeV. Another structure with even higher significance is found at a mass of 6847_{-28}^{+44}(stat)_{-20}^{+48}(syst) MeV, which is consistent with the X(6900) resonance reported by the LHCb experiment and confirmed by the ATLAS experiment. Evidence for another new structure, with a local significance of 4.7 standard deviations, is found at a mass of 7134_{-25}^{+48}(stat)_{-15}^{+41}(syst) MeV. Results are also reported for a model without interference, which does not fit the data as well and shows mass shifts up to 150 MeV relative to the model with interference.
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Search for Scalar Leptoquarks Produced via τ-Lepton-Quark Scattering in pp Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2024; 132:061801. [PMID: 38394587 DOI: 10.1103/physrevlett.132.061801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 12/19/2023] [Indexed: 02/25/2024]
Abstract
The first search for scalar leptoquarks produced in τ-lepton-quark collisions is presented. It is based on a set of proton-proton collision data recorded with the CMS detector at the LHC at a center-of-mass energy of 13 TeV corresponding to an integrated luminosity of 138 fb^{-1}. The reconstructed final state consists of a jet, significant missing transverse momentum, and a τ lepton reconstructed through its hadronic or leptonic decays. Limits are set on the product of the leptoquark production cross section and branching fraction and interpreted as exclusions in the plane of the leptoquark mass and the leptoquark-τ-quark coupling strength.
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Search for Inelastic Dark Matter in Events with Two Displaced Muons and Missing Transverse Momentum in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2024; 132:041802. [PMID: 38335361 DOI: 10.1103/physrevlett.132.041802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 09/24/2023] [Accepted: 11/29/2023] [Indexed: 02/12/2024]
Abstract
A search for dark matter in events with a displaced nonresonant muon pair and missing transverse momentum is presented. The analysis is performed using an integrated luminosity of 138 fb^{-1} of proton-proton (pp) collision data at a center-of-mass energy of 13 TeV produced by the LHC in 2016-2018. No significant excess over the predicted backgrounds is observed. Upper limits are set on the product of the inelastic dark matter production cross section σ(pp→A^{'}→χ_{1}χ_{2}) and the decay branching fraction B(χ_{2}→χ_{1}μ^{+}μ^{-}), where A^{'} is a dark photon and χ_{1} and χ_{2} are states in the dark sector with near mass degeneracy. This is the first dedicated collider search for inelastic dark matter.
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Probing Small Bjorken-x Nuclear Gluonic Structure via Coherent J/ψ Photoproduction in Ultraperipheral Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV. PHYSICAL REVIEW LETTERS 2023; 131:262301. [PMID: 38215362 DOI: 10.1103/physrevlett.131.262301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 08/17/2023] [Accepted: 10/26/2023] [Indexed: 01/14/2024]
Abstract
Quasireal photons exchanged in relativistic heavy ion interactions are powerful probes of the gluonic structure of nuclei. The coherent J/ψ photoproduction cross section in ultraperipheral lead-lead collisions is measured as a function of photon-nucleus center-of-mass energies per nucleon (W_{γN}^{Pb}) over a wide range of 40
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Observation of τ Lepton Pair Production in Ultraperipheral Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV. PHYSICAL REVIEW LETTERS 2023; 131:151803. [PMID: 37897747 DOI: 10.1103/physrevlett.131.151803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 08/31/2022] [Accepted: 10/28/2022] [Indexed: 10/30/2023]
Abstract
We present an observation of photon-photon production of τ lepton pairs in ultraperipheral lead-lead collisions. The measurement is based on a data sample with an integrated luminosity of 404 μb^{-1} collected by the CMS experiment at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02 TeV. The γγ→τ^{+}τ^{-} process is observed for τ^{+}τ^{-} events with a muon and three charged hadrons in the final state. The measured fiducial cross section is σ(γγ→τ^{+}τ^{-})=4.8±0.6(stat)±0.5(syst) μb, where the second (third) term corresponds to the statistical (systematic) uncertainty in σ(γγ→τ^{+}τ^{-}) in agreement with leading-order QED predictions. Using σ(γγ→τ^{+}τ^{-}), we estimate a model-dependent value of the anomalous magnetic moment of the τ lepton of a_{τ}=0.001_{-0.089}^{+0.055}.
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Long-Term Outcomes of De-Intensified Chemoradiotherapy for Human Papillomavirus-Associated Oropharyngeal Squamous Cell Carcinoma. Int J Radiat Oncol Biol Phys 2023; 117:S123-S124. [PMID: 37784319 DOI: 10.1016/j.ijrobp.2023.06.464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) To report long-term oncologic outcomes among patients with human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) treated with definitive de-intensified chemoradiotherapy. MATERIALS/METHODS Major criteria for de-intensification were (1) AJCC 7th edition T0-T3, N0-N2c, M0 (AJCC 8th edition T0-T3, N0-N2, M0), (2) pathologically confirmed p16 positive, and (3) no or minimal/remote smoking history (non-mutated p53 if ≥30 pack-years). Treatment was 60 Gy intensity-modulated radiotherapy with first-choice concurrent cisplatin 30 mg/m2 once per week (alternative regimens permissible for cisplatin ineligible patients). Patients with T0-T2 N0-1 (AJCC 7th edition) were recommended 60 Gy radiation alone. Systemic therapy received included: cisplatin 30 mg/m2 (n = 122), cetuximab (n = 15), cisplatin 40 mg/m2 (n = 12), carboplatin/paclitaxel (n = 2), and radiation alone (n = 25). Kaplan Meier estimates for overall survival (OS), progression-free survival (PFS), locoregional control (LRC), and freedom from distant metastasis (FFDM) were calculated. Cox regression models were used for comparisons among subgroups. RESULTS A total 176 patients received de-intensified treatment (n = 153 prospective protocol, n = 23 off-protocol). Median follow-up was 52.6 months (range 5.3 - 102.0, 90.8% with minimum 2-year follow-up); 56.8% (n = 100) were never smokers and 43.2% (n = 76) former smokers; former smokers had median 9 pack-years smoking history (range 0.25 - 50) with 46% ≥10 pack-years. Outcomes were as follows: 2-year OS 99.4% and 5-year OS 91.8%; 2-year PFS 94.1% and 5-year PFS 84.3%; 2-year LRC 98.3% and 5-year LRC 95.8%; 2-year FFDM 95.8% and 5-year FFDM 93.2%. Median time to progression events were 21.1 months (range, 7.2 - 54.1) with 37.5% (6 of 16) of recurrences occurring after 24 months. Six total locoregional events occurred (five recurrences and one site of persistent disease), within the 60 Gy planning target volume. Twenty-three patients with T0-T2 N0-1 disease received radiation alone with 2-year PFS 92.9% (5-year 83.8%) and 2-year LRC 100% (5-year 95.2%). Outcomes for former smokers with ≥10 pack-years were comparable to patients with less or no smoking history (2-year PFS 94.1% vs 94.1%; 5-year PFS 90.6% vs 82.7%; HR 0.58, p = 0.38). Early results suggest similar oncologic outcomes among those treated off-protocol (median follow-up 25.6 months) with 1 of 23 patients experiencing locoregional recurrence. CONCLUSION Dose de-intensification of 60 Gy radiotherapy with weekly cisplatin results in favorable long-term tumor control in patients with HPV-associated OPSCC. De-intensified 60 Gy alone may be efficacious in carefully selected patients with T0-T2 N0-1 (AJCC 7th edition) disease. Inclusion of biologically favorable patients with more extensive former smoking history in de-intensification clinical trials may be warranted.
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Five-Fraction Stereotactic Radiation for Head and Neck Paragangliomas. Int J Radiat Oncol Biol Phys 2023; 117:e183-e184. [PMID: 37784809 DOI: 10.1016/j.ijrobp.2023.06.1039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Paragangliomas of the head and neck (HN) are benign, slow-growing neoplasms that are rarely functional. Treatment is often indicated for patients presenting with mass effect, cranial neuropathies, or pulsatile tinnitus. Radiotherapy, traditionally conventionally fractionated, is often used for primary, post-operative, and salvage therapy, given its excellent control rates and reduced risks to adjacent neurovascular structures. Stereotactic ablative radiation (SAbR) offers shorter treatment time, and modern techniques eliminate margins to improve organ-at-risk avoidance. SAbR may offer additional radiobiological sparing of normal structures over single-fraction SAbR. We aimed to evaluate tumor and symptom response, acute and late toxicity rates, and recurrence patterns in HN paraganglioma patients treated with 25 Gy in 5 fractions. MATERIALS/METHODS Retrospective chart review collected baseline patient and tumor information, treatment and dosimetry details, acute and long-term toxicity grades (per the CTCAE v. 5.0), symptom and tumor response, and survival. Local control was defined as the absence of local enlargement (per RECIST v. 1.1) or marginal failure and was estimated using the Kaplan-Meier method. RESULTS Between December 2009-March 2020, 39 patients received 25 Gy in 5 fractions to 43 HN paragangliomas, of which 17 were treated in 11 patients with hereditary paraganglioma-pheochromocytoma syndrome. Fifteen targets were post-operative recurrent or residual tumors. There were 27 jugulotympanic tumors, 4 jugular, 1 tympanic, 8 vagal, 5 carotid body, and 2 jugulotympanic or vagal. Median follow-up time was 3.3 years (range 0-11.4 years), and 21 targets had at least 4 years of follow-up. Tumor volume decreased by a median of 37%. Three-year local control was 100%. One patient, known to harbor an SDHD mutation, had 2 out-of-field recurrences within the post-operative bed at 7.1 years. Two patients experienced 2 marginal recurrences within the post-operative bed at 6.1 and 8.4 years: one had an SDHB mutation and developed metastatic disease, and the other did not have genetic testing. The most common grade 1-2 acute toxicities were headache and fatigue; the most common grade 1-2 late toxicities were dysphagia and otalgia. There were no grade >2 acute toxicities. A late grade 3 aspiration event was seen in 1 patient who presented with paralyzed vocal cord requiring multiple medialization laryngoplasties. Within 6 months of SAbR, 18% of symptoms or toxicities improved or resolved; 34% improved or resolved more than 6 months after SAbR. CONCLUSION This is the largest series of HN paragangliomas treated with SAbR, detailing a 10-year experience with a 5-fraction regimen that is well-tolerated and achieves excellent local control. Post-SAbR recurrences occurred outside of the radiation field but within the post-operative bed, suggesting that some post-operative patients may benefit from expanded radiation volumes or close surveillance for salvage therapy.
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Balancing Quality and Efficiency of Head and Neck Contour Revision for Online Adaptive Radiotherapy. Int J Radiat Oncol Biol Phys 2023; 117:e734-e735. [PMID: 37786135 DOI: 10.1016/j.ijrobp.2023.06.2259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) The number of target and organs-at-risk (OAR) structures requiring contours is a barrier to online adaptive radiotherapy (oART) implementation for head and neck (H&N) cancer. In sharing our experience utilizing a cone beam CT-based oART system featuring automatic contours, we analyzed the system's clinical performance and the dosimetric benefits of human supervision to investigate the optimal balance between contour editing and plan quality. MATERIALS/METHODS We analyzed 44 H&N patients and 349 adaptive fractions treated on the oART system. The unsupervised (automatically generated) and supervised (edited by clinicians) target and OAR contours as well as the corresponding adaptive plans were acquired. Dice Similarity Coefficient (DSC) and Hausdorff Distance (HD) used to assess the geometric extent of contour supervision. We mapped the clinically treated adaptive plan to the unsupervised contours to quantify the dosimetric effect of the contour edits, and the adaptive plan optimized from the unsupervised contours to the supervised contours to simulate an unsupervised workflow. RESULTS The targets were edited in >80.7% of the sessions, with the most changes seen in the primary GTV (DSC = 0.86 ± 0.09 and HD = 2.77 ± 1.58 mm) and the least in the nodal CTV (DSC = 0.92 ± 0.06, HD = 2.29 ± 1.49 mm). Among OARs, oral cavity was the most frequently edited (49.0%) and brainstem the least (2.2%). In general, OAR edits were minor (mean DSC > 0.95 with std Dosimetric quantification of the edits (Table 1) showed that while the unsupervised targets resulted in significant coverage loss, the change in unsupervised OAR dose was not as pronounced, with 81.5-96.8% still meeting the preplan constraints. Edits corresponding to major dose changes were mostly adjacent to or inside targets. The unsupervised workflow underdosed the targets and overdosed the OARs, and therefore is not recommended. CONCLUSION While target contours needed physician supervision in H&N oART, edits to automatic OAR contours were minor. An alternative contour workflow could be adopted to focus on the targets and reduce time spent on the OARs. For OAR close to or overlapping with the targets, strategic cropping could potentially minimize time for editing and improve the robustness of the adapted plan quality.
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Measurement of the Dependence of the Hadron Production Fraction Ratios f_{s}/f_{u} and f_{d}/f_{u} on B Meson Kinematic Variables in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2023; 131:121901. [PMID: 37802954 DOI: 10.1103/physrevlett.131.121901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 03/27/2023] [Accepted: 06/20/2023] [Indexed: 10/08/2023]
Abstract
The dependence of the ratio between the B_{s}^{0} and B^{+} hadron production fractions, f_{s}/f_{u}, on the transverse momentum (p_{T}) and rapidity of the B mesons is studied using the decay channels B_{s}^{0}→J/ψϕ and B^{+}→J/ψK^{+}. The analysis uses a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the CMS experiment in 2018 and corresponding to an integrated luminosity of 61.6 fb^{-1}. The f_{s}/f_{u} ratio is observed to depend on the B p_{T} and to be consistent with becoming asymptotically constant at large p_{T}. No rapidity dependence is observed. The ratio of the B^{0} to B^{+} meson production fractions, f_{d}/f_{u}, is also measured, for the first time in proton-proton collisions, using the B^{0}→J/ψK^{*0} decay channel. The result is found to be within 1 standard deviation of unity and independent of p_{T} and rapidity, as expected from isospin invariance.
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Search for Exotic Higgs Boson Decays H→AA→4γ with Events Containing Two Merged Diphotons in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2023; 131:101801. [PMID: 37739361 DOI: 10.1103/physrevlett.131.101801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 01/19/2023] [Indexed: 09/24/2023]
Abstract
We present the first direct search for exotic Higgs boson decays H→AA, A→γγ in events with two photonlike objects. The hypothetical particle A is a low-mass spin-0 particle decaying promptly to a merged diphoton reconstructed as a single photonlike object. We analyze the data collected by the CMS experiment at sqrt[s]=13 TeV corresponding to an integrated luminosity of 136 fb^{-1}. No excess above the estimated background is found. We set upper limits on the branching fraction B(H→AA→4γ) of (0.9-3.3)×10^{-3} at 95% confidence level for masses of A in the range 0.1-1.2 GeV.
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Observation of Same-Sign WW Production from Double Parton Scattering in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2023; 131:091803. [PMID: 37721845 DOI: 10.1103/physrevlett.131.091803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 08/18/2022] [Indexed: 09/20/2023]
Abstract
The first observation of the production of W^{±}W^{±} bosons from double parton scattering processes using same-sign electron-muon and dimuon events in proton-proton collisions is reported. The data sample corresponds to an integrated luminosity of 138 fb^{-1} recorded at a center-of-mass energy of 13 TeV using the CMS detector at the CERN LHC. Multivariate discriminants are used to distinguish the signal process from the main backgrounds. A binned maximum likelihood fit is performed to extract the signal cross section. The measured cross section for production of same-sign W bosons decaying leptonically is 80.7±11.2(stat) _{-8.6}^{+9.5}(syst)±12.1(model) fb, whereas the measured fiducial cross section is 6.28±0.81(stat)±0.69(syst)±0.37(model) fb. The observed significance of the signal is 6.2 standard deviations above the background-only hypothesis.
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Observation of the Rare Decay of the η Meson to Four Muons. PHYSICAL REVIEW LETTERS 2023; 131:091903. [PMID: 37721839 DOI: 10.1103/physrevlett.131.091903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 06/14/2023] [Indexed: 09/20/2023]
Abstract
A search for the rare η→μ^{+}μ^{-}μ^{+}μ^{-} double-Dalitz decay is performed using a sample of proton-proton collisions, collected by the CMS experiment at the CERN LHC with high-rate muon triggers during 2017 and 2018 and corresponding to an integrated luminosity of 101 fb^{-1}. A signal having a statistical significance well in excess of 5 standard deviations is observed. Using the η→μ^{+}μ^{-} decay as normalization, the branching fraction B(η→μ^{+}μ^{-}μ^{+}μ^{-})=[5.0±0.8(stat)±0.7(syst)±0.7(B_{2μ})]×10^{-9} is measured, where the last term is the uncertainty in the normalization channel branching fraction. This work achieves an improved precision of over 5 orders of magnitude compared to previous results, leading to the first measurement of this branching fraction, which is found to agree with theoretical predictions.
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Search for Higgs Boson Decay to a Charm Quark-Antiquark Pair in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2023; 131:061801. [PMID: 37625071 DOI: 10.1103/physrevlett.131.061801] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 07/07/2022] [Indexed: 08/27/2023]
Abstract
A search for the standard model Higgs boson decaying to a charm quark-antiquark pair, H→cc[over ¯], produced in association with a leptonically decaying V (W or Z) boson is presented. The search is performed with proton-proton collisions at sqrt[s]=13 TeV collected by the CMS experiment, corresponding to an integrated luminosity of 138 fb^{-1}. Novel charm jet identification and analysis methods using machine learning techniques are employed. The analysis is validated by searching for Z→cc[over ¯] in VZ events, leading to its first observation at a hadron collider with a significance of 5.7 standard deviations. The observed (expected) upper limit on σ(VH)B(H→cc[over ¯]) is 0.94 (0.50_{-0.15}^{+0.22})pb at 95% confidence level (C.L.), corresponding to 14 (7.6_{-2.3}^{+3.4}) times the standard model prediction. For the Higgs-charm Yukawa coupling modifier, κ_{c}, the observed (expected) 95% C.L. interval is 1.1<|κ_{c}|<5.5 (|κ_{c}|<3.4), the most stringent constraint to date.
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Azimuthal Correlations within Exclusive Dijets with Large Momentum Transfer in Photon-Lead Collisions. PHYSICAL REVIEW LETTERS 2023; 131:051901. [PMID: 37595238 DOI: 10.1103/physrevlett.131.051901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 11/11/2022] [Accepted: 02/15/2023] [Indexed: 08/20/2023]
Abstract
The structure of nucleons is multidimensional and depends on the transverse momenta, spatial geometry, and polarization of the constituent partons. Such a structure can be studied using high-energy photons produced in ultraperipheral heavy-ion collisions. The first measurement of the azimuthal angular correlations of exclusively produced events with two jets in photon-lead interactions at large momentum transfer is presented, a process that is considered to be sensitive to the underlying nuclear gluon polarization. This study uses a data sample of ultraperipheral lead-lead collisions at sqrt[s_{NN}]=5.02 TeV, corresponding to an integrated luminosity of 0.38 nb^{-1}, collected with the CMS experiment at the LHC. The measured second harmonic of the correlation between the sum and difference of the two jet transverse momentum vectors is found to be positive, and rising, as the dijet transverse momentum increases. A well-tuned model that has been successful at describing a wide range of proton scattering data from the HERA experiments fails to describe the observed correlations, suggesting the presence of gluon polarization effects.
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Search for Nonresonant Pair Production of Highly Energetic Higgs Bosons Decaying to Bottom Quarks. PHYSICAL REVIEW LETTERS 2023; 131:041803. [PMID: 37566864 DOI: 10.1103/physrevlett.131.041803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 06/27/2022] [Indexed: 08/13/2023]
Abstract
A search for nonresonant Higgs boson (H) pair production via gluon and vector boson (V) fusion is performed in the four-bottom-quark final state, using proton-proton collision data at 13 TeV corresponding to 138 fb^{-1} collected by the CMS experiment at the LHC. The analysis targets Lorentz-boosted H pairs identified using a graph neural network. It constrains the strengths relative to the standard model of the H self-coupling and the quartic VVHH couplings, κ_{2V}, excluding κ_{2V}=0 for the first time, with a significance of 6.3 standard deviations when other H couplings are fixed to their standard model values.
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Search for Higgs Boson and Observation of Z Boson through Their Decay into a Charm Quark-Antiquark Pair in Boosted Topologies in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2023; 131:041801. [PMID: 37566854 DOI: 10.1103/physrevlett.131.041801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 04/09/2023] [Accepted: 04/11/2023] [Indexed: 08/13/2023]
Abstract
A search for the standard model (SM) Higgs boson (H) produced with transverse momentum (p_{T}) greater than 450 GeV and decaying to a charm quark-antiquark (cc[over ¯]) pair is presented. The search is performed using proton-proton collision data collected at sqrt[s]=13 TeV by the CMS experiment at the LHC, corresponding to an integrated luminosity of 138 fb^{-1}. Boosted H→cc[over ¯] decay products are reconstructed as a single large-radius jet and identified using a deep neural network charm tagging technique. The method is validated by measuring the Z→cc[over ¯] decay process, which is observed in association with jets at high p_{T} for the first time with a signal strength of 1.00_{-0.14}^{+0.17}(syst)±0.08(theo)±0.06(stat), defined as the ratio of the observed process rate to the SM expectation. The observed (expected) upper limit on σ(H)B(H→cc[over ¯]) is set at 47 (39) times the SM prediction at 95% confidence level.
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Probing Heavy Majorana Neutrinos and the Weinberg Operator through Vector Boson Fusion Processes in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2023; 131:011803. [PMID: 37478454 DOI: 10.1103/physrevlett.131.011803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 08/31/2022] [Indexed: 07/23/2023]
Abstract
The first search exploiting the vector boson fusion process to probe heavy Majorana neutrinos and the Weinberg operator at the LHC is presented. The search is performed in the same-sign dimuon final state using a proton-proton collision dataset recorded at sqrt[s]=13 TeV, collected with the CMS detector and corresponding to a total integrated luminosity of 138 fb^{-1}. The results are found to agree with the predictions of the standard model. For heavy Majorana neutrinos, constraints on the squared mixing element between the muon and the heavy neutrino are derived in the heavy neutrino mass range 50 GeV-25 TeV; for masses above 650 GeV these are the most stringent constraints from searches at the LHC to date. A first test of the Weinberg operator at colliders provides an observed upper limit at 95% confidence level on the effective μμ Majorana neutrino mass of 10.8 GeV.
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Apoptolidin I: A new glycosylated macrocyclic lactone from wasp gut bacterium, Amycolatopsis sp. Tetrahedron 2022. [DOI: 10.1016/j.tet.2022.133091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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21
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Search for Higgs Boson Pair Production in the Four b Quark Final State in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2022; 129:081802. [PMID: 36053704 DOI: 10.1103/physrevlett.129.081802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Accepted: 07/07/2022] [Indexed: 06/15/2023]
Abstract
A search for pairs of Higgs bosons produced via gluon and vector boson fusion is presented, focusing on the four b quark final state. The data sample consists of proton-proton collisions at a center-of-mass energy of 13 TeV, collected with the CMS detector at the LHC, and corresponds to an integrated luminosity of 138 fb^{-1}. No deviation from the background-only hypothesis is observed. A 95% confidence level upper limit on the Higgs boson pair production cross section is observed at 3.9 times the standard model prediction for an expected value of 7.8. Constraints are also set on the modifiers of the Higgs field self-coupling, κ_{λ}, and of the coupling of two Higgs bosons to two vector bosons, κ_{2 V}. The observed (expected) allowed intervals at the 95% confidence level are -2.3<κ_{λ}<9.4 (-5.0<κ_{λ}<12.0) and -0.1<κ_{2 V}<2.2 (-0.4<κ_{2 V}<2.5). These are the most stringent observed constraints to date on the HH production cross section and on the κ_{2 V } coupling.
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22
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Search for Flavor-Changing Neutral Current Interactions of the Top Quark and Higgs Boson in Final States with Two Photons in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2022; 129:032001. [PMID: 35905365 DOI: 10.1103/physrevlett.129.032001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 06/13/2022] [Indexed: 06/15/2023]
Abstract
Proton-proton interactions resulting in final states with two photons are studied in a search for the signature of flavor-changing neutral current interactions of top quarks (t) and Higgs bosons (H). The analysis is based on data collected at a center-of-mass energy of 13 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 137 fb^{-1}. No significant excess above the background prediction is observed. Upper limits on the branching fractions (B) of the top quark decaying to a Higgs boson and an up (u) or charm (c) quark are derived through a binned fit to the diphoton invariant mass spectrum. The observed (expected) 95% confidence level upper limits are found to be 0.019% (0.031%) for B(t→Hu) and 0.073% (0.051%) for B(t→Hc). These are the strictest upper limits yet determined.
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Search for Resonances Decaying to Three W Bosons in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2022; 129:021802. [PMID: 35867460 DOI: 10.1103/physrevlett.129.021802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
A search for resonances decaying into a W boson and a radion, where the radion decays into two W bosons, is presented. The data analyzed correspond to an integrated luminosity of 138 fb^{-1} recorded in proton-proton collisions with the CMS detector at sqrt[s]=13 TeV. One isolated charged lepton is required, together with missing transverse momentum and one or two massive large-radius jets, containing the decay products of either two or one W bosons, respectively. No excess over the background estimation is observed. The results are combined with those from a complementary channel with an all-hadronic final state, described in an accompanying paper. Limits are set on parameters of an extended warped extra-dimensional model. These searches are the first of their kind at the LHC.
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Probing Charm Quark Dynamics via Multiparticle Correlations in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV. PHYSICAL REVIEW LETTERS 2022; 129:022001. [PMID: 35867464 DOI: 10.1103/physrevlett.129.022001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 05/11/2022] [Accepted: 05/18/2022] [Indexed: 06/15/2023]
Abstract
Multiparticle azimuthal correlations of prompt D^{0} mesons are measured in Pb-Pb collisions at a nucleon-nucleon center-of-mass energy of sqrt[s_{NN}]=5.02 TeV. For the first time, a four-particle cumulant method is used to extract the second Fourier coefficient of the azimuthal distribution (v_{2}) of D^{0} mesons as a function of event centrality and the D^{0} transverse momentum. The ratios of the four-particle v_{2} values to previously measured two-particle cumulant results provide direct experimental access to event-by-event fluctuations of charm quark azimuthal anisotropies. These ratios are also found to be comparable to those of inclusive charged particles in the event. However, hints of deviations are seen in the most central and peripheral collisions. To investigate the origin of flow fluctuations in the charm sector, these measurements are compared to a model implementing fluctuations of charm quark energy loss via collisional or radiative processes in the quark-gluon plasma. These models cannot quantitatively describe the data over the full transverse momentum and centrality ranges, although the calculations with collisional energy loss provide a better description of the data.
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First Search for Exclusive Diphoton Production at High Mass with Tagged Protons in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2022; 129:011801. [PMID: 35841572 DOI: 10.1103/physrevlett.129.011801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 05/09/2022] [Accepted: 05/16/2022] [Indexed: 06/15/2023]
Abstract
A search for exclusive two-photon production via photon exchange in proton-proton collisions, pp→pγγp with intact protons, is presented. The data correspond to an integrated luminosity of 9.4 fb^{-1} collected in 2016 using the CMS and TOTEM detectors at a center-of-mass energy of 13 TeV at the LHC. Events are selected with a diphoton invariant mass above 350 GeV and with both protons intact in the final state, to reduce backgrounds from strong interactions. The events of interest are those where the invariant mass and rapidity calculated from the momentum losses of the forward-moving protons match the mass and rapidity of the central, two-photon system. No events are found that satisfy this condition. Interpreting this result in an effective dimension-8 extension of the standard model, the first limits are set on the two anomalous four-photon coupling parameters. If the other parameter is constrained to its standard model value, the limits at 95% confidence level are |ζ_{1}|<2.9×10^{-13} GeV^{-4} and |ζ_{2}|<6.0×10^{-13} GeV^{-4}.
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Observation of the B_{c}^{+} Meson in Pb-Pb and pp Collisions at sqrt[s_{NN}]=5.02 TeV and Measurement of its Nuclear Modification Factor. PHYSICAL REVIEW LETTERS 2022; 128:252301. [PMID: 35802434 DOI: 10.1103/physrevlett.128.252301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 02/23/2022] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
The B_{c}^{+} meson is observed for the first time in heavy ion collisions. Data from the CMS detector are used to study the production of the B_{c}^{+} meson in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02 TeV, via the B_{c}^{+}→(J/ψ→μ^{+}μ^{-})μ^{+}ν_{μ} decay. The B_{c}^{+} nuclear modification factor, derived from the Pb-Pb-to-pp ratio of production cross sections, is measured in two bins of the trimuon transverse momentum and of the Pb-Pb collision centrality. The B_{c}^{+} meson is shown to be less suppressed than quarkonia and most of the open heavy-flavor mesons, suggesting that effects of the hot and dense nuclear matter created in heavy ion collisions contribute to its production. This measurement sets forth a promising new probe of the interplay of suppression and enhancement mechanisms in the production of heavy-flavor mesons in the quark-gluon plasma.
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Taeanamides A and B, Nonribosomal Lipo-Decapeptides Isolated from an Intertidal-Mudflat-Derived Streptomyces sp. Mar Drugs 2022; 20:md20060400. [PMID: 35736203 PMCID: PMC9229766 DOI: 10.3390/md20060400] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 06/10/2022] [Accepted: 06/13/2022] [Indexed: 12/04/2022] Open
Abstract
Two new lipo-decapeptides, namely taeanamides A and B (1 and 2), were discovered from the Gram-positive bacterium Streptomyces sp. AMD43, which was isolated from a mudflat sample from Anmyeondo, Korea. The exact molecular masses of 1 and 2 were revealed by high-resolution mass spectrometry, and the planar structures of 1 and 2 were elucidated using NMR spectroscopy. The absolute configurations of 1 and 2 were determined using a combined analysis of 1H-1H coupling constants and ROESY correlations, the advanced Marfey’s method, and bioinformatics. The putative nonribosomal peptide synthetase pathway for the taeanamides was identified by analyzing the full genome sequence data of Streptomyces sp. AMD43. We also found that taeanamide A exhibited mild anti-tuberculosis bioactivity, whereas taeanamide B showed significant bioactivity against several cancer cell lines.
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Using Z Boson Events to Study Parton-Medium Interactions in Pb-Pb Collisions. PHYSICAL REVIEW LETTERS 2022; 128:122301. [PMID: 35394329 DOI: 10.1103/physrevlett.128.122301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 01/16/2022] [Accepted: 02/25/2022] [Indexed: 06/14/2023]
Abstract
The spectra measurements of charged hadrons produced in the shower of a parton originating in the same hard scattering with a leptonically decaying Z boson are reported in lead-lead nuclei (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. Both Pb-Pb and pp data sets are recorded by the CMS experiment at the LHC and correspond to an integrated luminosity of 1.7 nb^{-1} and 320 pb^{-1}, respectively. Hadronic collision data with one reconstructed Z boson candidate with the transverse momentum p_{T}>30 GeV/c are analyzed. The Z boson constrains the initial energy and direction of the associated parton. In heavy ion events, azimuthal angular distributions of charged hadrons with respect to the direction of a Z boson are sensitive to modifications of the in-medium parton shower and medium response. compared to reference data from pp interactions, the results for central Pb-Pb collisions indicate a modification of the angular correlations. The measurements of the fragmentation functions and p_{T} spectra of charged particles in Z boson events, which are sensitive to medium modifications of the parton shower longitudinal structure, are also reported. Significant modifications in central Pb-Pb events compared to the pp reference data are also found for these observables.
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Measurement of the Inclusive and Differential Higgs Boson Production Cross Sections in the Decay Mode to a Pair of τ Leptons in pp Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2022; 128:081805. [PMID: 35275660 DOI: 10.1103/physrevlett.128.081805] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 01/24/2022] [Indexed: 06/14/2023]
Abstract
Measurements of the inclusive and differential fiducial cross sections of the Higgs boson are presented, using the τ lepton decay channel. The differential cross sections are measured as functions of the Higgs boson transverse momentum, jet multiplicity, and transverse momentum of the leading jet in the event, if any. The analysis is performed using proton-proton collision data collected with the CMS detector at the LHC at a center-of-mass energy of 13 TeV and corresponding to an integrated luminosity of 138 fb^{-1}. These are the first differential measurements of the Higgs boson cross section in the final state of two τ leptons. In final states with a large jet multiplicity or with a Lorentz-boosted Higgs boson, these measurements constitute a significant improvement over measurements performed in other final states.
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Gwanakosides A and B, 6-Deoxy-α-l-talopyranose-Bearing Aromatic Metabolites from a Streptomyces sp. and Coculture with Pandoraea sp. JOURNAL OF NATURAL PRODUCTS 2022; 85:83-90. [PMID: 34931849 DOI: 10.1021/acs.jnatprod.1c00703] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Single-strain cultivation of a mountain soil-derived Streptomyces sp. GA02 and its coculture with Pandoraea sp. GA02N produced two aromatic products, gwanakosides A and B (1 and 2, respectively). Their spectroscopic analysis revealed that 1 is a new dichlorinated naphthalene glycoside and 2 is a pentacyclic aromatic glycoside. The assignment of the two chlorine atoms in 1 was confirmed by the analysis of its band-selective CLIP-HSQMBC spectrum. The sugars in the gwanakosides were identified as 6-deoxy-α-l-talopyranose based on 1H-1H coupling constants, Rotating frame Overhauser enhancement spectroscopy (ROESY) NMR correlations, and chemical derivatization followed by spectroscopic and chromatographic analyses. The absolute configuration of 2, whose production was enhanced approximately 100-fold in coculture, was proposed based on a quantum mechanics-based chemical shift analysis method, DP4 calculations, and the chemically determined configuration of 6-deoxy-α-l-talopyranose. Gwanakoside A displayed inhibitory activity against pathogenic bacteria, including Staphylococcus aureus (MIC = 8 μg/mL) and Mycobacterium tuberculosis (MIC50 = 15 μg/mL), and antiproliferative activity against several human cancer cell lines (IC50 = 5.6-19.4 μM).
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Evidence for X(3872) in Pb-Pb Collisions and Studies of its Prompt Production at sqrt[s_{NN}]=5.02 TeV. PHYSICAL REVIEW LETTERS 2022; 128:032001. [PMID: 35119878 DOI: 10.1103/physrevlett.128.032001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 09/02/2021] [Accepted: 12/22/2021] [Indexed: 06/14/2023]
Abstract
The first evidence for X(3872) production in relativistic heavy ion collisions is reported. The X(3872) production is studied in lead-lead (Pb-Pb) collisions at a center-of-mass energy of sqrt[s_{NN}]=5.02 TeV per nucleon pair, using the decay chain X(3872)→J/ψπ^{+}π^{-}→μ^{+}μ^{-}π^{+}π^{-}. The data were recorded with the CMS detector in 2018 and correspond to an integrated luminosity of 1.7 nb^{-1}. The measurement is performed in the rapidity and transverse momentum ranges |y|<1.6 and 15<p_{T}<50 GeV/c. The significance of the inclusive X(3872) signal is 4.2 standard deviations. The prompt X(3872) to ψ2S yield ratio is found to be ρ^{Pb-Pb}=1.08±0.49(stat)±0.52(syst), to be compared with typical values of 0.1 for pp collisions. This result provides a unique experimental input to theoretical models of the X(3872) production mechanism, and of the nature of this exotic state.
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32
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Search for Long-Lived Particles Decaying in the CMS End Cap Muon Detectors in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2021; 127:261804. [PMID: 35029469 DOI: 10.1103/physrevlett.127.261804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 09/18/2021] [Accepted: 10/26/2021] [Indexed: 06/14/2023]
Abstract
A search for long-lived particles (LLPs) produced in decays of standard model (SM) Higgs bosons is presented. The data sample consists of 137 fb^{-1} of proton-proton collisions at sqrt[s]=13 TeV, recorded at the LHC in 2016-2018. A novel technique is employed to reconstruct decays of LLPs in the end cap muon detectors. The search is sensitive to a broad range of LLP decay modes and to masses as low as a few GeV. No excess of events above the SM background is observed. The most stringent limits to date on the branching fraction of the Higgs boson to LLPs subsequently decaying to quarks and τ^{+}τ^{-} are found for proper decay lengths greater than 6, 20, and 40 m, for LLP masses of 7, 15, and 40 GeV, respectively.
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Measurements of the Electroweak Diboson Production Cross Sections in Proton-Proton Collisions at sqrt[s]=5.02 TeV Using Leptonic Decays. PHYSICAL REVIEW LETTERS 2021; 127:191801. [PMID: 34797136 DOI: 10.1103/physrevlett.127.191801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 09/22/2021] [Indexed: 06/13/2023]
Abstract
The first measurements of diboson production cross sections in proton-proton interactions at a center-of-mass energy of 5.02 TeV are reported. They are based on data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 302 pb^{-1}. Events with two, three, or four charged light leptons (electrons or muons) in the final state are analyzed. The WW, WZ, and ZZ total cross sections are measured as σ_{WW}=37.0_{-5.2}^{+5.5}(stat)_{-2.6}^{+2.7}(syst) pb, σ_{WZ}=6.4_{-2.1}^{+2.5}(stat)_{-0.3}^{+0.5}(syst) pb, and σ_{ZZ}=5.3_{-2.1}^{+2.5}(stat)_{-0.4}^{+0.5}(syst) pb. All measurements are in good agreement with theoretical calculations at combined next-to-next-to-leading order quantum chromodynamics and next-to-leading order electroweak accuracy.
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Observation of Forward Neutron Multiplicity Dependence of Dimuon Acoplanarity in Ultraperipheral Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV. PHYSICAL REVIEW LETTERS 2021; 127:122001. [PMID: 34597080 DOI: 10.1103/physrevlett.127.122001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 04/20/2021] [Accepted: 07/21/2021] [Indexed: 06/13/2023]
Abstract
The first measurement of the dependence of γγ→μ^{+}μ^{-} production on the multiplicity of neutrons emitted very close to the beam direction in ultraperipheral heavy ion collisions is reported. Data for lead-lead interactions at sqrt[s_{NN}]=5.02 TeV, with an integrated luminosity of approximately 1.5 nb^{-1}, are collected using the CMS detector at the LHC. The azimuthal correlations between the two muons in the invariant mass region 8<m_{μμ}<60 GeV are extracted for events including 0, 1, or at least 2 neutrons detected in the forward pseudorapidity range |η|>8.3. The back-to-back correlation structure from leading-order photon-photon scattering is found to be significantly broader for events with a larger number of emitted neutrons from each nucleus, corresponding to interactions with a smaller impact parameter. This observation provides a data-driven demonstration that the average transverse momentum of photons emitted from relativistic heavy ions has an impact parameter dependence. These results provide new constraints on models of photon-induced interactions in ultraperipheral collisions. They also provide a baseline to search for possible final-state effects on lepton pairs caused by traversing a quark-gluon plasma produced in hadronic heavy ion collisions.
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Constraints on the Initial State of Pb-Pb Collisions via Measurements of Z-Boson Yields and Azimuthal Anisotropy at sqrt[s_{NN}]=5.02 TeV. PHYSICAL REVIEW LETTERS 2021; 127:102002. [PMID: 34533355 DOI: 10.1103/physrevlett.127.102002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/17/2021] [Accepted: 07/27/2021] [Indexed: 06/13/2023]
Abstract
The CMS experiment at the LHC has measured the differential cross sections of Z bosons decaying to pairs of leptons, as functions of transverse momentum and rapidity, in lead-lead collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. The measured Z boson elliptic azimuthal anisotropy coefficient is compatible with zero, showing that Z bosons do not experience significant final-state interactions in the medium produced in the collision. Yields of Z bosons are compared to Glauber model predictions and are found to deviate from these expectations in peripheral collisions, indicating the presence of initial collision geometry and centrality selection effects. The precision of the measurement allows, for the first time, for a data-driven determination of the nucleon-nucleon integrated luminosity as a function of lead-lead centrality, thereby eliminating the need for its estimation based on a Glauber model.
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Measurement of the Wγ Production Cross Section in Proton-Proton Collisions at sqrt[s]=13 TeV and Constraints on Effective Field Theory Coefficients. PHYSICAL REVIEW LETTERS 2021; 126:252002. [PMID: 34241533 DOI: 10.1103/physrevlett.126.252002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/12/2021] [Accepted: 05/11/2021] [Indexed: 06/13/2023]
Abstract
A fiducial cross section for Wγ production in proton-proton collisions is measured at a center-of-mass energy of 13 TeV in 137 fb^{-1} of data collected using the CMS detector at the LHC. The W→eν and μν decay modes are used in a maximum-likelihood fit to the lepton-photon invariant mass distribution to extract the combined cross section. The measured cross section is compared with theoretical expectations at next-to-leading order in quantum chromodynamics. In addition, 95% confidence level intervals are reported for anomalous triple-gauge couplings within the framework of effective field theory.
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Observation of a New Excited Beauty Strange Baryon Decaying to Ξ_{b}^{-}π^{+}π^{-}. PHYSICAL REVIEW LETTERS 2021; 126:252003. [PMID: 34241504 DOI: 10.1103/physrevlett.126.252003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 03/19/2021] [Accepted: 04/23/2021] [Indexed: 06/13/2023]
Abstract
The Ξ_{b}^{-}π^{+}π^{-} invariant mass spectrum is investigated with an event sample of proton-proton collisions at sqrt[s]=13 TeV, collected by the CMS experiment at the LHC in 2016-2018 and corresponding to an integrated luminosity of 140 fb^{-1}. The ground state Ξ_{b}^{-} is reconstructed via its decays to J/ψΞ^{-} and J/ψΛK^{-}. A narrow resonance, labeled Ξ_{b}(6100)^{-}, is observed at a Ξ_{b}^{-}π^{+}π^{-} invariant mass of 6100.3±0.2(stat)±0.1(syst)±0.6(Ξ_{b}^{-}) MeV, where the last uncertainty reflects the precision of the Ξ_{b}^{-} baryon mass. The upper limit on the Ξ_{b}(6100)^{-} natural width is determined to be 1.9 MeV at 95% confidence level. The low Ξ_{b}(6100)^{-} signal yield observed in data does not allow a measurement of the quantum numbers of the new state. However, following analogies with the established excited Ξ_{c} baryon states, the new Ξ_{b}(6100)^{-} resonance and its decay sequence are consistent with the orbitally excited Ξ_{b}^{-} baryon, with spin and parity quantum numbers J^{P}=3/2^{-}.
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Evidence for Top Quark Production in Nucleus-Nucleus Collisions. PHYSICAL REVIEW LETTERS 2020; 125:222001. [PMID: 33315428 DOI: 10.1103/physrevlett.125.222001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 10/07/2020] [Indexed: 06/12/2023]
Abstract
Ultrarelativistic heavy ion collisions recreate in the laboratory the thermodynamical conditions prevailing in the early universe up to 10^{-6} sec, thereby allowing the study of the quark-gluon plasma (QGP), a state of quantum chromodynamics (QCD) matter with deconfined partons. The top quark, the heaviest elementary particle known, is accessible in nucleus-nucleus collisions at the CERN LHC, and constitutes a novel probe of the QGP. Here, we report the first evidence for the production of top quarks in nucleus-nucleus collisions, using lead-lead collision data at a nucleon-nucleon center-of-mass energy of 5.02 TeV recorded by the CMS experiment. Two methods are used to measure the cross section for top quark pair production (σ_{tt[over ¯]}) via the selection of charged leptons (electrons or muons) and bottom quarks. One method relies on the leptonic information alone, and the second one exploits, in addition, the presence of bottom quarks. The measured cross sections, σ_{tt[over ¯]}=2.54_{-0.74}^{+0.84} and 2.03_{-0.64}^{+0.71} μb, respectively, are compatible with expectations from scaled proton-proton data and QCD predictions.
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39
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Search for Sub-eV Sterile Neutrinos at RENO. PHYSICAL REVIEW LETTERS 2020; 125:191801. [PMID: 33216576 DOI: 10.1103/physrevlett.125.191801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 10/08/2020] [Accepted: 10/09/2020] [Indexed: 06/11/2023]
Abstract
We report a search result for a light sterile neutrino oscillation with roughly 2200 live days of data in the RENO experiment. The search is performed by electron antineutrino (ν[over ¯]_{e}) disappearance taking place between six 2.8 GW_{th} reactors and two identical detectors located at 294 m (near) and 1383 m (far) from the center of the reactor array. A spectral comparison between near and far detectors can explore reactor ν[over ¯]_{e} oscillations to a light sterile neutrino. An observed spectral difference is found to be consistent with that of the three-flavor oscillation model. This yields limits on sin^{2}2θ_{14} in the 10^{-4}≲|Δm_{41}^{2}|≲0.5 eV^{2} region, free from reactor ν[over ¯]_{e} flux and spectrum uncertainties. The RENO result provides the most stringent limits on sterile neutrino mixing at |Δm_{41}^{2}|≲0.002 eV^{2} using the ν[over ¯]_{e} disappearance channel.
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40
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Observation of the B_{s}^{0}→X(3872)ϕ Decay. PHYSICAL REVIEW LETTERS 2020; 125:152001. [PMID: 33095627 DOI: 10.1103/physrevlett.125.152001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 06/22/2020] [Accepted: 08/27/2020] [Indexed: 06/11/2023]
Abstract
Using a data sample of proton-proton collisions at sqrt[s]=13 TeV, corresponding to an integrated luminosity of 140 fb^{-1} collected by the CMS experiment in 2016-2018, the B_{s}^{0}→X(3872)ϕ decay is observed. Decays into J/ψπ^{+}π^{-} and K^{+}K^{-} are used to reconstruct, respectively, the X(3872) and ϕ. The ratio of the product of branching fractions B[B_{s}^{0}→X(3872)ϕ]B[X(3872)→J/ψπ^{+}π^{-}] to the product B[B_{s}^{0}→ψ(2S)ϕ]B[ψ(2S)→J/ψπ^{+}π^{-}] is measured to be [2.21±0.29(stat)±0.17(syst)]%. The ratio B[B_{s}^{0}→X(3872)ϕ]/B[B^{0}→X(3872)K^{0}] is found to be consistent with one, while the ratio B[B_{s}^{0}→X(3872)ϕ]/B[B^{+}→X(3872)K^{+}] is two times smaller. This suggests a difference in the production dynamics of the X(3872) in B^{0} and B_{s}^{0} meson decays compared to B^{+}. The reported observation may shed new light on the nature of the X(3872) particle.
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Observation of the Production of Three Massive Gauge Bosons at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2020; 125:151802. [PMID: 33095594 DOI: 10.1103/physrevlett.125.151802] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 08/24/2020] [Indexed: 06/11/2023]
Abstract
The first observation is reported of the combined production of three massive gauge bosons (VVV with V=W, Z) in proton-proton collisions at a center-of-mass energy of 13 TeV. The analysis is based on a data sample recorded by the CMS experiment at the CERN LHC corresponding to an integrated luminosity of 137 fb^{-1}. The searches for individual WWW, WWZ, WZZ, and ZZZ production are performed in final states with three, four, five, and six leptons (electrons or muons), or with two same-sign leptons plus one or two jets. The observed (expected) significance of the combined VVV production signal is 5.7 (5.9) standard deviations and the corresponding measured cross section relative to the standard model prediction is 1.02_{-0.23}^{+0.26}. The significances of the individual WWW and WWZ production are 3.3 and 3.4 standard deviations, respectively. Measured production cross sections for the individual triboson processes are also reported.
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Studies of Charm Quark Diffusion inside Jets Using Pb-Pb and pp Collisions at sqrt[s_{NN}]=5.02 TeV. PHYSICAL REVIEW LETTERS 2020; 125:102001. [PMID: 32955327 DOI: 10.1103/physrevlett.125.102001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 05/28/2020] [Accepted: 08/05/2020] [Indexed: 06/11/2023]
Abstract
The first study of charm quark diffusion with respect to the jet axis in heavy ion collisions is presented. The measurement is performed using jets with p_{T}^{jet}>60 GeV/c and D^{0} mesons with p_{T}^{D}>4 GeV/c in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of sqrt[s_{NN}]=5.02 TeV, recorded by the CMS detector at the LHC. The radial distribution of D^{0} mesons with respect to the jet axis is sensitive to the production mechanisms of the meson, as well as to the energy loss and diffusion processes undergone by its parent parton inside the strongly interacting medium produced in Pb-Pb collisions. When compared to Monte Carlo event generators, the radial distribution in pp collisions is found to be well described by pythia, while the slope of the distribution predicted by sherpa is steeper than that of the data. In Pb-Pb collisions, compared to the pp results, the D^{0} meson distribution for 4<p_{T}^{D}<20 GeV/c hints at a larger distance on average with respect to the jet axis, reflecting a diffusion of charm quarks in the medium created in heavy ion collisions. At higher p_{T}^{D}, the Pb-Pb and pp radial distributions are found to be similar.
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Measurements of tt[over ¯]H Production and the CP Structure of the Yukawa Interaction between the Higgs Boson and Top Quark in the Diphoton Decay Channel. PHYSICAL REVIEW LETTERS 2020; 125:061801. [PMID: 32845700 DOI: 10.1103/physrevlett.125.061801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 06/19/2020] [Indexed: 06/11/2023]
Abstract
The first observation of the tt[over ¯]H process in a single Higgs boson decay channel with the full reconstruction of the final state (H→γγ) is presented, with a significance of 6.6 standard deviations (σ). The CP structure of Higgs boson couplings to fermions is measured, resulting in an exclusion of the pure CP-odd structure of the top Yukawa coupling at 3.2σ. The measurements are based on a sample of proton-proton collisions at a center-of-mass energy sqrt[s]=13 TeV collected by the CMS detector at the LHC, corresponding to an integrated luminosity of 137 fb^{-1}. The cross section times branching fraction of the tt[over ¯]H process is measured to be σ_{tt[over ¯]H}B_{γγ}=1.56_{-0.32}^{+0.34} fb, which is compatible with the standard model prediction of 1.13_{-0.11}^{+0.08} fb. The fractional contribution of the CP-odd component is measured to be f_{CP}^{Htt}=0.00±0.33.
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Measurement of the Jet Mass Distribution and Top Quark Mass in Hadronic Decays of Boosted Top Quarks in pp Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2020; 124:202001. [PMID: 32501048 DOI: 10.1103/physrevlett.124.202001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Revised: 03/25/2020] [Accepted: 05/01/2020] [Indexed: 06/11/2023]
Abstract
A measurement is reported of the jet mass distribution in hadronic decays of boosted top quarks produced in pp collisions at sqrt[s]=13 TeV. The data were collected with the CMS detector at the LHC and correspond to an integrated luminosity of 35.9 fb^{-1}. The measurement is performed in the lepton+jets channel of tt[over ¯] events, where the lepton is an electron or muon. The products of the hadronic top quark decay t→bW→bqq[over ¯]^{'} are reconstructed as a single jet with transverse momentum larger than 400 GeV. The tt[over ¯] cross section as a function of the jet mass is unfolded at the particle level and used to extract a value of the top quark mass of 172.6±2.5 GeV. A novel jet reconstruction technique is used for the first time at the LHC, which improves the precision by a factor of 3 relative to an earlier measurement. This highlights the potential of measurements using boosted top quarks, where the new technique will enable future precision measurements.
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Constraints on the χ_{c1} versus χ_{c2} Polarizations in Proton-Proton Collisions at sqrt[s]=8 TeV. PHYSICAL REVIEW LETTERS 2020; 124:162002. [PMID: 32383915 DOI: 10.1103/physrevlett.124.162002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/25/2020] [Accepted: 03/26/2020] [Indexed: 06/11/2023]
Abstract
The polarizations of promptly produced χ_{c1} and χ_{c2} mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at sqrt[s]=8 TeV. The χ_{c} states are reconstructed via their radiative decays χ_{c}→J/ψγ, with the photons being measured through conversions to e^{+}e^{-}, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_{c2} to χ_{c1} yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ→μ^{+}μ^{-} decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum.
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Search for a Narrow Resonance Lighter than 200 GeV Decaying to a Pair of Muons in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2020; 124:131802. [PMID: 32302170 DOI: 10.1103/physrevlett.124.131802] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 02/24/2020] [Indexed: 06/11/2023]
Abstract
A search is presented for a narrow resonance decaying to a pair of oppositely charged muons using sqrt[s]=13 TeV proton-proton collision data recorded at the LHC. In the 45-75 and 110-200 GeV resonance mass ranges, the search is based on conventional triggering and event reconstruction techniques. In the 11.5-45 GeV mass range, the search uses data collected with dimuon triggers with low transverse momentum thresholds, recorded at high rate by storing a reduced amount of trigger-level information. The data correspond to integrated luminosities of 137 and 96.6 fb^{-1} for conventional and high-rate triggering, respectively. No significant resonant peaks are observed in the probed mass ranges. The search sets the most stringent constraints to date on a dark photon in the ∼30-75 and 110-200 GeV mass ranges.
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Search for Supersymmetry with a Compressed Mass Spectrum in Events with a Soft τ Lepton, a Highly Energetic Jet, and Large Missing Transverse Momentum in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2020; 124:041803. [PMID: 32058742 DOI: 10.1103/physrevlett.124.041803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Indexed: 06/10/2023]
Abstract
The first search for supersymmetry in events with an experimental signature of one soft, hadronically decaying τ lepton, one energetic jet from initial-state radiation, and large transverse momentum imbalance is presented. These event signatures are consistent with direct or indirect production of scalar τ leptons (τ[over ˜]) in supersymmetric models that exhibit coannihilation between the τ[over ˜] and the lightest neutralino (χ[over ˜]_{1}^{0}), and that could generate the observed relic density of dark matter. The data correspond to an integrated luminosity of 77.2 fb^{-1} of proton-proton collisions at sqrt[s]=13 TeV collected with the CMS detector at the LHC in 2016 and 2017. The results are interpreted in a supersymmetric scenario with a small mass difference (Δm) between the chargino (χ[over ˜]_{1}^{±}) or next-to-lightest neutralino (χ[over ˜]_{2}^{0}), and the χ[over ˜]_{1}^{0}. The mass of the τ[over ˜] is assumed to be the average of the χ[over ˜]_{1}^{±} and χ[over ˜]_{1}^{0} masses. The data are consistent with standard model background predictions. Upper limits at 95% confidence level are set on the sum of the χ[over ˜]_{1}^{±}, χ[over ˜]_{2}^{0}, and τ[over ˜] production cross sections for Δm(χ[over ˜]_{1}^{±},χ[over ˜]_{1}^{0})=50 GeV, resulting in a lower limit of 290 GeV on the mass of the χ[over ˜]_{1}^{±}, which is the most stringent to date and surpasses the bounds from the LEP experiments.
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Search for Physics beyond the Standard Model in Events with Overlapping Photons and Jets. PHYSICAL REVIEW LETTERS 2019; 123:241801. [PMID: 31922872 DOI: 10.1103/physrevlett.123.241801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 10/23/2019] [Indexed: 06/10/2023]
Abstract
Results are reported from a search for new particles that decay into a photon and two gluons, in events with jets. Novel jet substructure techniques are developed that allow photons to be identified in an environment densely populated with hadrons. The analyzed proton-proton collision data were collected by the CMS experiment at the LHC, in 2016 at sqrt[s]=13 TeV, and correspond to an integrated luminosity of 35.9 fb^{-1}. The spectra of total transverse hadronic energy of candidate events are examined for deviations from the standard model predictions. No statistically significant excess is observed over the expected background. The first cross section limits on new physics processes resulting in such events are set. The results are interpreted as upper limits on the rate of gluino pair production, utilizing a simplified stealth supersymmetry model. The excluded gluino masses extend up to 1.7 TeV, for a neutralino mass of 200 GeV and exceed previous mass constraints set by analyses targeting events with isolated photons.
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Search for Low-Mass Quark-Antiquark Resonances Produced in Association with a Photon at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2019; 123:231803. [PMID: 31868480 DOI: 10.1103/physrevlett.123.231803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 10/12/2019] [Indexed: 06/10/2023]
Abstract
A search for narrow low-mass resonances decaying to quark-antiquark pairs is presented. The search is based on proton-proton collision events collected at 13 TeV by the CMS detector at the CERN LHC. The data sample corresponds to an integrated luminosity of 35.9 fb^{-1}, recorded in 2016. The search considers the case where the resonance has high transverse momentum due to initial-state radiation of a hard photon. To study this process, the decay products of the resonance are reconstructed as a single large-radius jet with two-pronged substructure. The signal would be identified as a localized excess in the jet invariant mass spectrum. No evidence for such a resonance is observed in the mass range 10 to 125 GeV. Upper limits at the 95% confidence level are set on the coupling strength of resonances decaying to quark pairs. The results obtained with this photon trigger strategy provide the first direct constraints on quark-antiquark resonance masses below 50 GeV obtained at a hadron collider.
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Search for a Light Charged Higgs Boson Decaying to a W Boson and a CP-Odd Higgs Boson in Final States with eμμ or μμμ in Proton-Proton Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2019; 123:131802. [PMID: 31697516 DOI: 10.1103/physrevlett.123.131802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Revised: 07/19/2019] [Indexed: 06/10/2023]
Abstract
A search for a light charged Higgs boson (H^{+}) decaying to a W boson and a CP-odd Higgs boson (A) in final states with eμμ or μμμ is performed using data from pp collisions at sqrt[s]=13 TeV, recorded by the CMS detector at the LHC and corresponding to an integrated luminosity of 35.9 fb^{-1}. In this search, it is assumed that the H^{+} boson is produced in decays of top quarks, and the A boson decays to two oppositely charged muons. The presence of signals for H^{+} boson masses between 100 and 160 GeV and A boson masses between 15 and 75 GeV is investigated. No evidence for the production of the H^{+} boson is found. Upper limits at 95% confidence level are obtained on the combined branching fraction for the decay chain, t→bH^{+}→bW^{+}A→bW^{+}μ^{+}μ^{-}, of 1.9×10^{-6} to 8.6×10^{-6}, depending on the masses of the H^{+} and A bosons. These are the first limits for these decay modes of the H^{+} and A bosons.
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