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Nightshift work and irregular menstrual cycle: 8-year follow-up cohort study. Occup Med (Lond) 2024; 74:152-160. [PMID: 38330390 DOI: 10.1093/occmed/kqad162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2024] Open
Abstract
BACKGROUND Irregular menstruation is a major health problem among women, although its association with nightshift work remains controversial. AIMS To study the association between nightshift work and irregular menstrual cycle among female workers and investigate any differences according to sleep quality, working hours or obesity. METHODS This study included female workers who underwent health examinations from 2012 to 2019. Nightshift work, working hours, sleep quality and menstrual cycles were assessed using self-administered questionnaires. Irregular menstrual cycle was defined as self-reported irregular or ≥36 days. Adjusted odds ratios and 95% confidence intervals (CIs) were calculated by multivariable logistic regression; adjusted hazard ratios (95% CIs) for incident irregular menstrual cycle were calculated by Cox proportional hazard models with time-dependent analysis. RESULTS The study participants were 87 147 in the cross-sectional study and 41 516 in the longitudinal study. After adjusting for all covariates in the cross-sectional analyses, the odds ratio for prevalent irregular menstrual cycle among female nightshift workers versus the reference was 1.26 (95% CI 1.2-1.33). In the cohort study, the adjusted hazard ratio for incident irregular menstrual cycle among nightshift workers was 1.95 (95% CI 1.61-2.35) in the period after 6 years. No significant differences were observed among subgroups stratified by sleep quality, working hours or obesity. CONCLUSIONS Nightshift work is associated with an increased risk of both prevalent and incident irregular menstrual cycle in female workers without significant interactions by sleep quality, working hours or obesity.
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Utility of Stereotactic Body Radiation Therapy (SBRT) in Establishing Local Control for Invasive Breast Cancer Patients Not Undergoing Definitive Surgery. Int J Radiat Oncol Biol Phys 2023; 117:e199. [PMID: 37784845 DOI: 10.1016/j.ijrobp.2023.06.1073] [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) Breast cancer (BC) treatment involves a multi-modal approach where surgical resection is the backbone of therapy. However, due to medical comorbidities precluding surgery, unresectable disease, or patient preference, some patients do not undergo surgery. In the absence of resection, it is paramount to improve local control (LC) of the primary tumor. To that end, this study explored the role of ablative RT dose delivered with SBRT. MATERIALS/METHODS Between 2015-2022, 21 patients (10 metastatic, 11 stage IA-IIIC) received 23 SBRT courses to primary BC lesions without planned surgery at our institution. One patient had undergone whole breast RT 20 years prior to SBRT. 7 patients were analyzed retrospectively; 15 are currently enrolled in a prospective study. SBRT dose was 40 Gy/5 fractions delivered every other day. Follow-up imaging (PET, CT, MRI, MMG/US) was reviewed to evaluate the response. CTCAE v.3 was used to document any acute (≤3 months) and late toxicities. Kaplan-Meier curves were used to estimate local control (LC) and overall survival (OS). RESULTS Median age was 78.4 (45.9-97.3) years. Median follow-up was 14.7 (3.3-70.3) months after RT completion. Initial post-treatment imaging was available for all cases and was performed at a median of 4.0 (0.6-11.9) months after SBRT. The median pre-SBRT index lesion size was 3.1 (0.5-14.5) cm and PTV was 32.4 (11.5-522.4) cc. At a median 4 months post-SBRT, the median decrease in index lesion size was 20.8 (0-100) % and SUV reduction was 65.2 (20.8-100) %. Further improvement was seen on the 2nd follow-up scans at a median 7.8 months post-SBRT, with 62 (0-100) % and 88 (33.3-100) % median reduction in the tumor size and SUV, respectively, compared to pre-SBRT values. The estimated LC rate was 100% at 6 months and 93.3% at 12 months. The sole case of local progression occurred 9.5 months after SBRT, after an initial interval decrease in the primary lesion. Among the patients with available systemic follow-up scans, regional progression occurred in 4 (17.4%) cases at a median 18.6 (5.2-22.7) months post-SBRT. Six (37.5%) patients developed distant progression at a median 4.8 (0.9-16.2) months, all of whom had metastatic disease at diagnosis. The estimated OS was 85.7% at 6 months and 63.8% at 12 months. Most patients tolerated the treatment well. There was no grade 4 toxicity. Complete acute toxicity data is presented in Table 1. Only one patient experienced late grade 2 breast edema. CONCLUSION Based on our preliminary results, definitive SBRT to the primary BC appears to have a role in providing LC in the treatment of non-surgical patients and is well-tolerated. Since the disease progression tends to occur outside the treated primary tumor, additional approaches to improve regional and distant control should be investigated.
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Predictive Value of Pre-Treatment MRI Radiomics for Distant Brain Metastases Following Stereotactic Radiosurgery/Radiotherapy. Int J Radiat Oncol Biol Phys 2023; 117:e84. [PMID: 37786196 DOI: 10.1016/j.ijrobp.2023.06.835] [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) Local intracranial therapy for brain metastases (BM) has taken on particular importance as survival among metastatic patients improves. However, the development of distant BMs (DBMs) outside the treated area remains a stubborn problem for which canonical clinical features (age, histology, ECOG PS) have limited predictive capability. In this study, we hypothesized that MRI-based "radiomic" features (sub-visual cues extracted from diagnostic images) can accurately predict the time-to-DBM development (TTDD) on a retrospectively curated dataset of patients treated with stereotactic radiosurgery/radiotherapy (SRS/SRT). MATERIALS/METHODS We queried our treatment planning system for patients treated with brain SRS/SRT between 2014 and 2021, and curated the incidence/timing of DBMs manually. Pre-RT MRI sequences (T1 pre, T1 post, T2, and FLAIR) and planning data were obtained for each patient. MRI and CT simulations were co-registered using affine transformations, and regions of interest (ROIs) were identified based on contoured structures (GTV) and discrete isodose ranges (0-25%, 25-50%, 50-75%, 75%+). Radiomic features were extracted from these ROIs, and clinical features (ECOG PS, tumor volume, age) were recorded for baseline comparison. Features were selected using Wald test scores from univariate Cox proportional hazard (CPH) models. Multivariate CPH models were then trained to predict TTDD using combinations of selected features. Predictive capability was evaluated using concordance index (c-index) values. A radiomic risk score (RRS) was created to discriminate patients with low and high-risk for DBMs, and evaluated using a log-rank test. RESULTS A total of 105 patients were selected with a median follow up of 356 days. 53 patients developed DBMs (median time 118 days). Radiomic CPH models achieved a c-index of 0.63 compared to clinical baseline of 0.49. The combination of radiomic and clinical features achieved the highest c-index of 0.69. Overall, radiomic features with and without clinical features were able to stratify patients into low and high-risk groups with statistically significant differences in TTDD development (see Table 1). Clinical features alone were not significant. The most predictive radiomic features were identified within the T1 pre-contrast MRI from the 50-75% isodose regions, followed by T2 FLAIR/GTV and T2/GTV combinations. CONCLUSION Radiomic features from routine MR scans were more predictive of TTDD than baseline clinical features. The contribution from the 50-75% isodose region suggests importance within the peritumoral environment in addition to the tumor itself.
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Time-resolved Coulomb collision of single electrons. NATURE NANOTECHNOLOGY 2023:10.1038/s41565-023-01369-4. [PMID: 37169897 DOI: 10.1038/s41565-023-01369-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 03/10/2023] [Indexed: 05/13/2023]
Abstract
A series of recent experiments have shown that collision of ballistic electrons in semiconductors can be used to probe the indistinguishability of single-electron wavepackets. Perhaps surprisingly, their Coulomb interaction has not been seen due to screening. Here we show Coulomb-dominated collision of high-energy single electrons in counter-propagating ballistic edge states, probed by measuring partition statistics while adjusting the collision timing. Although some experimental data suggest antibunching behaviour, we show that this is not due to quantum statistics but to strong repulsive Coulomb interactions. This prevents the wavepacket overlap needed for fermionic exchange statistics but suggests new ways to utilize Coulomb interactions: microscopically isolated and time-resolved interactions between ballistic electrons can enable the use of the Coulomb interaction for high-speed sensing or gate operations on flying electron qubits.
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Artificial Intelligence-Assisted Peer Review in Radiation Oncology. Int J Radiat Oncol Biol Phys 2022. [DOI: 10.1016/j.ijrobp.2022.07.1726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Pre-Radiation CT-Based Radiomic Features Predict Locoregional and Distant Failure in Locally Advanced Head and Neck Cancer. Int J Radiat Oncol Biol Phys 2022. [DOI: 10.1016/j.ijrobp.2022.07.1330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Abstract
The extension of life span driven by 40% caloric restriction (CR) in rodents causes trade-offs in growth, reproduction, and immune defense that make it difficult to identify therapeutically relevant CR-mimetic targets. We report that about 14% CR for 2 years in healthy humans improved thymopoiesis and was correlated with mobilization of intrathymic ectopic lipid. CR-induced transcriptional reprogramming in adipose tissue implicated pathways regulating mitochondrial bioenergetics, anti-inflammatory responses, and longevity. Expression of the gene Pla2g7 encoding platelet activating factor acetyl hydrolase (PLA2G7) is inhibited in humans undergoing CR. Deletion of Pla2g7 in mice showed decreased thymic lipoatrophy, protection against age-related inflammation, lowered NLRP3 inflammasome activation, and improved metabolic health. Therefore, the reduction of PLA2G7 may mediate the immunometabolic effects of CR and could potentially be harnessed to lower inflammation and extend the health span.
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THE COMBINATION OF DUVELISIB AND ROMIDEPSIN (DR) IS HIGHLY ACTIVE AGAINST RELAPSED/REFRACTORY PERIPHERAL T‐CELL LYMPHOMA WITH LOW RATES OF TRANSAMINITIS: FINAL RESULTS. Hematol Oncol 2021. [DOI: 10.1002/hon.56_2879] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Definitive Stereotactic Body Radiation Therapy in The Local Management of Breast Cancer. Int J Radiat Oncol Biol Phys 2020. [DOI: 10.1016/j.ijrobp.2020.07.1162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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NTCP Modeling of Hypothyroidism after Supraclavicular-Directed Radiation Therapy for Breast Cancer. Int J Radiat Oncol Biol Phys 2020. [DOI: 10.1016/j.ijrobp.2020.07.1033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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PO-1820: Repolarized macrophages, induced by SRS and anti-PD; mediate long-term survival in murine glioma. Radiother Oncol 2020. [DOI: 10.1016/s0167-8140(21)01838-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Weekly High-Dose Rate Brachytherapy Via Surface Applicator For Non-Melanoma Skin Cancers In The Elderly. Int J Radiat Oncol Biol Phys 2020. [DOI: 10.1016/j.ijrobp.2020.07.288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Experimental effects of acute exercise on forgetting. Physiol Int 2020; 107:359-375. [PMID: 32990655 DOI: 10.1556/2060.2020.00033] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Accepted: 07/07/2020] [Indexed: 12/23/2022]
Abstract
Objective Prior research has evaluated the effects of acute exercise on episodic memory function. These studies have, on occasion, demonstrated that acute exercise may enhance both short- and long-term memory. It is uncertain as to whether the acute exercise improvements in long-term memory are a result of acute exercise attenuating declines in long-term memory, or rather, are driven by the enhancement effects of acute exercise on short-term memory. The present empirical study evaluates whether the decline from short- to long-term is influenced by acute exercise. This relationship is plausible as exercise has been shown to activate neurophysiological pathways (e.g., RAC1) that are involved in the mechanisms of forgetting. Methods To evaluate the effects of acute exercise on forgetting, we used data from 12 of our laboratory's prior experiments (N = 538). Across these 12 experiments, acute exercise ranged from 10 to 15 mins in duration (moderate-to-vigorous intensity). Episodic memory was assessed from word-list or paragraph-based assessments. Short-term memory was assessed immediately after encoding, with long-term memory assessed approximately 20-min later. Forgetting was calculated as the difference in short- and long-term memory performance. Results Acute exercise (vs. seated control) was not associated with an attenuated forgetting effect (d = 0.10; 95% CI: -0.04, 0.25, P = 0.17). We observed no evidence of a significant moderation effect (Q = 6.16, df = 17, P = 0.17, I2 = 0.00) for any of the evaluated parameters, including study design, exercise intensity and delay period. Conclusion Across our 12 experimental studies, acute exercise was not associated with an attenuated forgetting effect. We discuss these implications for future research that evaluates the effects of acute exercise on long-term memory function.
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Light sheet fluorescence microscopy using axi-symmetric binary phase filters. BIOMEDICAL OPTICS EXPRESS 2020; 11:3936-3951. [PMID: 33014577 PMCID: PMC7510890 DOI: 10.1364/boe.394841] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/30/2020] [Accepted: 06/17/2020] [Indexed: 05/29/2023]
Abstract
Light sheet fluorescence microscopy (LSFM) has become an indispensable tool in biomedical studies owing to its depth-sectioning capability and low photo-bleaching. The axial resolution in LSFM is determined mainly by the thickness of the illumination sheet, and a high numerical-aperture lens is thus preferred in the illumination to increase the axial resolution. However, a rapid divergence of the illumination beam limits the effective field-of-view (FoV), that provides high-resolution images. Several strategies have been demonstrated for FoV enhancement, which involve the use of Bessel or Airy beams, for example. However, the generation of these beams requires complicated optical setup or phase filters with continuous phase distributions, which are difficult to manufacture. In contrast, a binary phase filter (BPF) comprising concentric rings with 0 or π phases produces a response similar to its continuous original and is easy to realize. Here, we present a novel form of LSFM that integrates BPFs derived from two representative axi-symmetric aberrations, including phase axicon and spherical aberrations, to improve the imaging performance. We demonstrate that these BPFs significantly increase the FoV, and those derived from axicon generate self-reconstructing beams, which are highly desirable in imaging through scattering specimens. We validate its high-contrast imaging capability over extended FoV by presenting three-dimensional images of microspheres, imaginal disc of Drosophila larva, and Arabidopsis.
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Subclinical thyroid dysfunction, bone mineral density, and osteoporosis in a middle-aged Korean population. Osteoporos Int 2020; 31:547-555. [PMID: 31720711 DOI: 10.1007/s00198-019-05205-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 10/22/2019] [Indexed: 12/01/2022]
Abstract
UNLABELLED Thyroid dysfunction is associated with the loss of bone density (osteoporosis). However, the connection between subclinical thyroid dysfunction and osteoporosis remains controversial. This study found no apparent association between subclinical hypothyroidism or subclinical hyperthyroidism and bone mineral density (BMD) in the lumbar spine and femur. INTRODUCTION The present study examined the relationship between subclinical thyroid dysfunction and BMD in healthy middle-aged adults. METHODS A total of 25,510 healthy Koreans with normal free thyroxine levels were enrolled from January 2011 to December 2016, and 91% of subjects visited only once. The average age of the 15,761 women was 45, and the average age of the 9749 men was 48. Levels of thyroid-stimulating hormone (TSH) and BMD were recorded in all subjects. BMD was measured using dual-energy X-ray absorptiometry. RESULTS No apparent association was found between subclinical thyroid dysfunction and BMD in the lumbar spine, femur-neck, and proximal femur sites compared with a euthyroid group. Age, body mass index (BMI), and postmenopausal status affected BMD in women, and only BMI affected BMD in men. Subclinical hypothyroidism was independently associated with a lower risk of osteoporosis (odds ratio 0.657, 95% confidence interval 0.464-0.930) in 4710 postmenopausal women. CONCLUSIONS No apparent association was found between subclinical hypothyroidism or subclinical hyperthyroidism defined on single TSH measurement and BMD at the lumbar spine and femur in a large cohort of middle-aged men and women. Subclinical hypothyroidism was independently associated with a lower risk of osteoporosis in postmenopausal women.
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Mechanical stimulation of growth plate chondrocytes: Previous approaches and future directions. EXPERIMENTAL MECHANICS 2019; 59:1261-1274. [PMID: 31787777 PMCID: PMC6884322 DOI: 10.1007/s11340-018-0424-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Growth plate cartilage resides near the ends of long bones and is the primary driver of skeletal growth. During growth, both intrinsically and extrinsically generated mechanical stresses act on chondrocytes in the growth plate. Although the role of mechanical stresses in promoting tissue growth and homeostasis has been strongly demonstrated in articular cartilage of the major skeletal joints, effects of stresses on growth plate cartilage and bone growth are not as well established. Here, we review the literature on mechanobiology in growth plate cartilage at macroscopic and microscopic scales, with particular emphasis on comparison of results obtained using different methodological approaches, as well as from whole animal and in vitro experiments. To answer these questions, macroscopic mechanical stimulators have been developed and applied to study mechanobiology of growth plate cartilage and chondrocytes. However, the previous approaches have tested a limited number of stress conditions, and the mechanobiology of a single chondrocyte has not been well studied due to limitations of the macroscopic mechanical stimulators. We explore how microfluidics devices can overcome these limitations and improve current understanding of growth plate chondrocyte mechanobiology. In particular, microfluidic devices can generate multiple stress conditions in a single platform and enable real-time monitoring of metabolism and cellular behavior using optical microscopy. Systematic characterization of the chondrocytes using microfluidics will enhance our understanding of how to use mechanical stresses to control the bone growth and the properties of tissue-engineered growth plate cartilage.
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Observation of Electroweak Production of a Same-Sign W Boson Pair in Association with Two Jets in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2019; 123:161801. [PMID: 31702349 DOI: 10.1103/physrevlett.123.161801] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Indexed: 06/10/2023]
Abstract
This Letter presents the observation and measurement of electroweak production of a same-sign W boson pair in association with two jets using 36.1 fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of sqrt[s]=13 TeV by the ATLAS detector at the Large Hadron Collider. The analysis is performed in the detector fiducial phase-space region, defined by the presence of two same-sign leptons, electron or muon, and at least two jets with a large invariant mass and rapidity difference. A total of 122 candidate events are observed for a background expectation of 69±7 events, corresponding to an observed signal significance of 6.5 standard deviations. The measured fiducial signal cross section is σ^{fid}=2.89_{-0.48}^{+0.51}(stat)_{-0.28}^{+0.29}(syst) fb.
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A Multi-Platform Treatment Planning Benchmark Study for Spinal Radiosurgery. Int J Radiat Oncol Biol Phys 2019. [DOI: 10.1016/j.ijrobp.2019.06.810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Radiosurgery Compared To External Beam Radiotherapy for Localized Spine Metastasis: Phase III Results of NRG Oncology/RTOG 0631. Int J Radiat Oncol Biol Phys 2019. [DOI: 10.1016/j.ijrobp.2019.06.382] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Comparison of Fragmentation Functions for Jets Dominated by Light Quarks and Gluons from pp and Pb+Pb Collisions in ATLAS. PHYSICAL REVIEW LETTERS 2019; 123:042001. [PMID: 31491254 DOI: 10.1103/physrevlett.123.042001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 05/21/2019] [Indexed: 06/10/2023]
Abstract
Charged-particle fragmentation functions for jets azimuthally balanced by a high-transverse-momentum, prompt, isolated photon are measured in 25 pb^{-1} of pp and 0.49 nb^{-1} of Pb+Pb collision data at 5.02 TeV per nucleon pair recorded with the ATLAS detector at the Large Hadron Collider. The measurements are compared to predictions of Monte Carlo generators and to measurements of inclusively selected jets. In pp collisions, a different jet fragmentation function in photon-tagged events from that in inclusive jet events arises from the difference in fragmentation between light quarks and gluons. The ratios of the fragmentation functions in Pb+Pb events to that in pp events are used to explore the parton color-charge dependence of jet quenching in the hot medium. In relatively peripheral collisions, fragmentation functions exhibit a similar modification pattern for photon-tagged and inclusive jets. However, photon-tagged jets are observed to have larger modifications than inclusive jets in central Pb+Pb events.
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Clinical importance of colonoscopy in patients with gastric cancer. Ann Oncol 2019. [DOI: 10.1093/annonc/mdz155.181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Combination of Searches for Invisible Higgs Boson Decays with the ATLAS Experiment. PHYSICAL REVIEW LETTERS 2019; 122:231801. [PMID: 31298882 DOI: 10.1103/physrevlett.122.231801] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Indexed: 06/10/2023]
Abstract
Dark matter particles, if sufficiently light, may be produced in decays of the Higgs boson. This Letter presents a statistical combination of searches for H→invisible decays where H is produced according to the standard model via vector boson fusion, Z(ℓℓ)H, and W/Z(had)H, all performed with the ATLAS detector using 36.1 fb^{-1} of pp collisions at a center-of-mass energy of sqrt[s]=13 TeV at the LHC. In combination with the results at sqrt[s]=7 and 8 TeV, an exclusion limit on the H→invisible branching ratio of 0.26(0.17_{-0.05}^{+0.07}) at 95% confidence level is observed (expected).
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Measurement of the
tt¯Z
and
tt¯W
cross sections in proton-proton collisions at
s=13 TeV
with the ATLAS detector. Int J Clin Exp Med 2019. [DOI: 10.1103/physrevd.99.072009] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Search for the Production of a Long-Lived Neutral Particle Decaying within the ATLAS Hadronic Calorimeter in Association with a Z Boson from pp Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2019; 122:151801. [PMID: 31050493 DOI: 10.1103/physrevlett.122.151801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Indexed: 06/09/2023]
Abstract
This Letter presents a search for the production of a long-lived neutral particle (Z_{d}) decaying within the ATLAS hadronic calorimeter, in association with a standard model (SM) Z boson produced via an intermediate scalar boson, where Z→ℓ^{+}ℓ^{-} (ℓ=e, μ). The data used were collected by the ATLAS detector during 2015 and 2016 pp collisions with a center-of-mass energy of sqrt[s]=13 TeV at the Large Hadron Collider and correspond to an integrated luminosity of 36.1±0.8 fb^{-1}. No significant excess of events is observed above the expected background. Limits on the production cross section of the scalar boson times its decay branching fraction into the long-lived neutral particle are derived as a function of the mass of the intermediate scalar boson, the mass of the long-lived neutral particle, and its cτ from a few centimeters to one hundred meters. In the case that the intermediate scalar boson is the SM Higgs boson, its decay branching fraction to a long-lived neutral particle with a cτ approximately between 0.1 and 7 m is excluded with a 95% confidence level up to 10% for m_{Z_{d}} between 5 and 15 GeV.
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Cross-section measurements of the Higgs boson decaying into a pair of
τ
-leptons in proton-proton collisions at
s=13 TeV
with the ATLAS detector. Int J Clin Exp Med 2019. [DOI: 10.1103/physrevd.99.072001] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Effect of the Lactobacillus rhamnosus strain GG and tagatose as a synbiotic combination in a dextran sulfate sodium-induced colitis murine model. J Dairy Sci 2019; 102:2844-2853. [DOI: 10.3168/jds.2018-15013] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 07/09/2018] [Indexed: 12/30/2022]
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Three-Step Thermal Drawing for Rapid Prototyping of Highly Customizable Microneedles for Vascular Tissue Insertion. Pharmaceutics 2019; 11:pharmaceutics11030100. [PMID: 30813634 PMCID: PMC6470662 DOI: 10.3390/pharmaceutics11030100] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 02/20/2019] [Accepted: 02/21/2019] [Indexed: 01/24/2023] Open
Abstract
Microneedles (MNs) have been extensively developed over the last two decades, and highly efficient drug delivery was demonstrated with their minimal invasiveness via a transdermal route. Recently, MNs have not only been applied to the skin but also to other tissues such as blood vessels, scleral tissue, and corneal tissue. In addition, the objective of the MN application has been diversified, ranging from drug delivery to wound closure and biosensing. However, since most MN fabrication methods are expensive and time-consuming, they are inappropriate to prototype MNs for various tissues that have different and complex anatomies. Although several drawing-based techniques have been introduced for rapid MN production, they fabricated MNs with limited shapes, such as thin MNs with wide bases. In this study, we propose a three-step thermal drawing for rapid, prototyping MNs that can have a variety of shapes and can be fabricated on curved surfaces. Based on the temperature control of polymer bridge formation during thermal drawing, the body profile and aspect ratios of MNs were conveniently controlled, and the effect of temperature control on the body profile of MNs was explained. Thermally drawn MNs with different shapes were fabricated both on flat and curved surfaces, and they were characterized in terms of their mechanical properties and insertion into vascular tissue to find an optimal shape for vascular tissue insertion.
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Search for doubly charged scalar bosons decaying into same-sign W boson pairs with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2019; 79:58. [PMID: 30872971 PMCID: PMC6383730 DOI: 10.1140/epjc/s10052-018-6500-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 12/07/2018] [Indexed: 05/29/2023]
Abstract
A search for doubly charged scalar bosons decaying into W boson pairs is presented. It uses a data sample from proton-proton collisions corresponding to an integrated luminosity of 36.1 fb - 1 collected by the ATLAS detector at the LHC at a centre-of-mass energy of 13 TeV in 2015 and 2016. This search is guided by a model that includes an extension of the Higgs sector through a scalar triplet, leading to a rich phenomenology that includes doubly charged scalar bosons H ± ± . Those bosons are produced in pairs in proton-proton collisions and decay predominantly into electroweak gauge bosons H ± ± → W ± W ± . Experimental signatures with several leptons, missing transverse energy and jets are explored. No significant deviations from the Standard Model predictions are found. The parameter space of the benchmark model is excluded at 95% confidence level for H ± ± bosons with masses between 200 and 220 GeV.
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30
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Erratum to: Measurement of the W boson polarisation in t t ¯ events from pp collisions at s = 8 TeV in the lepton + jets channel with ATLAS. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2019; 79:19. [PMID: 31187788 PMCID: PMC6390723 DOI: 10.1140/epjc/s10052-018-6520-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 12/07/2018] [Indexed: 06/09/2023]
Abstract
[This corrects the article DOI: 10.1140/epjc/s10052-017-4819-4.].
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31
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Search for Higgs boson pair production in the γ γ W W ∗ channel using pp collision data recorded at s = 13 TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:1007. [PMID: 30872957 PMCID: PMC6383910 DOI: 10.1140/epjc/s10052-018-6457-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 11/14/2018] [Indexed: 06/09/2023]
Abstract
Searches for non-resonant and resonant Higgs boson pair production are performed in the γ γ W W ∗ channel with the final state of γ γ ℓ ν j j using 36.1 fb - 1 of proton-proton collision data recorded at a centre-of-mass energy ofs = 13 TeV by the ATLAS detector at the Large Hadron Collider. No significant deviation from the Standard Model prediction is observed. A 95% confidence-level observed upper limit of 7.7 pb is set on the cross section for non-resonant production, while the expected limit is 5.4 pb. A search for a narrow-width resonance X decaying to a pair of Standard Model Higgs bosons HH is performed with the same set of data, and the observed upper limits on σ ( p p → X ) × B ( X → H H ) range between 40.0 and 6.1 pb for masses of the resonance between 260 and 500 GeV, while the expected limits range between 17.6 and 4.4 pb. When deriving the limits above, the Standard Model branching ratios of the H → γ γ and H → W W ∗ are assumed.
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32
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Measurement of the azimuthal anisotropy of charged particles produced in s NN = 5.02 TeV Pb+Pb collisions with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:997. [PMID: 30872955 PMCID: PMC6383885 DOI: 10.1140/epjc/s10052-018-6468-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 11/20/2018] [Indexed: 06/09/2023]
Abstract
Measurements of the azimuthal anisotropy in lead-lead collisions ats NN = 5.02 TeV are presented using a data sample corresponding to 0.49nb - 1 integrated luminosity collected by the ATLAS experiment at the LHC in 2015. The recorded minimum-bias sample is enhanced by triggers for "ultra-central" collisions, providing an opportunity to perform detailed study of flow harmonics in the regime where the initial state is dominated by fluctuations. The anisotropy of the charged-particle azimuthal angle distributions is characterized by the Fourier coefficients, v 2 - v 7 , which are measured using the two-particle correlation, scalar-product and event-plane methods. The goal of the paper is to provide measurements of the differential as well as integrated flow harmonics v n over wide ranges of the transverse momentum, 0.5 < p T < 60 GeV, the pseudorapidity, | η | < 2.5, and the collision centrality 0-80%. Results from different methods are compared and discussed in the context of previous and recent measurements in Pb+Pb collisions ats NN = 2.76 TeV and 5.02 TeV . In particular, the shape of the p T dependence of elliptic or triangular flow harmonics is observed to be very similar at different centralities after scaling the v n and p T values by constant factors over the centrality interval 0-60% and the p T range 0.5 < p T < 5 GeV.
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33
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Search for electroweak production of supersymmetric particles in final states with two or three leptons at s = 13 TeV with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:995. [PMID: 30872954 PMCID: PMC6383936 DOI: 10.1140/epjc/s10052-018-6423-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 11/07/2018] [Indexed: 05/07/2023]
Abstract
A search for the electroweak production of charginos, neutralinos and sleptons decaying into final states involving two or three electrons or muons is presented. The analysis is based on 36.1 fb- 1 ofs = 13 TeV proton-proton collisions recorded by the ATLAS detector at the Large Hadron Collider. Several scenarios based on simplified models are considered. These include the associated production of the next-to-lightest neutralino and the lightest chargino, followed by their decays into final states with leptons and the lightest neutralino via either sleptons or Standard Model gauge bosons; direct production of chargino pairs, which in turn decay into leptons and the lightest neutralino via intermediate sleptons; and slepton pair production, where each slepton decays directly into the lightest neutralino and a lepton. No significant deviations from the Standard Model expectation are observed and stringent limits at 95% confidence level are placed on the masses of relevant supersymmetric particles in each of these scenarios. For a massless lightest neutralino, masses up to 580 GeV are excluded for the associated production of the next-to-lightest neutralino and the lightest chargino, assuming gauge-boson mediated decays, whereas for slepton-pair production masses up to 500 GeV are excluded assuming three generations of mass-degenerate sleptons.
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34
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Operation and performance of the ATLAS Tile Calorimeter in Run 1. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:987. [PMID: 30872953 PMCID: PMC6383937 DOI: 10.1140/epjc/s10052-018-6374-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 10/29/2018] [Indexed: 06/09/2023]
Abstract
The Tile Calorimeter is the hadron calorimeter covering the central region of the ATLAS experiment at the Large Hadron Collider. Approximately 10,000 photomultipliers collect light from scintillating tiles acting as the active material sandwiched between slabs of steel absorber. This paper gives an overview of the calorimeter's performance during the years 2008-2012 using cosmic-ray muon events and proton-proton collision data at centre-of-mass energies of 7 and 8 TeV with a total integrated luminosity of nearly 30 fb - 1 . The signal reconstruction methods, calibration systems as well as the detector operation status are presented. The energy and time calibration methods performed excellently, resulting in good stability of the calorimeter response under varying conditions during the LHC Run 1. Finally, the Tile Calorimeter response to isolated muons and hadrons as well as to jets from proton-proton collisions is presented. The results demonstrate excellent performance in accord with specifications mentioned in the Technical Design Report.
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35
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Combination of the Searches for Pair-Produced Vectorlike Partners of the Third-Generation Quarks at sqrt[s]=13 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2018; 121:211801. [PMID: 30517796 DOI: 10.1103/physrevlett.121.211801] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Indexed: 06/09/2023]
Abstract
A combination of the searches for pair-produced vectorlike partners of the top and bottom quarks in various decay channels (T→Zt/Wb/Ht, B→Zb/Wt/Hb) is performed using 36.1 fb^{-1} of pp collision data at sqrt[s]=13 TeV with the ATLAS detector at the Large Hadron Collider. The observed data are found to be in good agreement with the standard model background prediction in all individual searches. Therefore, combined 95% confidence-level upper limits are set on the production cross section for a range of vectorlike quark scenarios, significantly improving upon the reach of the individual searches. Model-independent limits are set assuming the vectorlike quarks decay to standard model particles. A singlet T is excluded for masses below 1.31 TeV and a singlet B is excluded for masses below 1.22 TeV. Assuming a weak isospin (T,B) doublet and |V_{Tb}|≪|V_{tB}|, T and B masses below 1.37 TeV are excluded.
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36
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Observation of Centrality-Dependent Acoplanarity for Muon Pairs Produced via Two-Photon Scattering in Pb+Pb Collisions at sqrt[s_{NN}]=5.02 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2018; 121:212301. [PMID: 30517793 DOI: 10.1103/physrevlett.121.212301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 08/14/2018] [Indexed: 06/09/2023]
Abstract
This Letter presents a measurement of γγ→μ^{+}μ^{-} production in Pb+Pb collisions recorded by the ATLAS detector at the Large Hadron Collider at sqrt[s_{NN}]=5.02 TeV with an integrated luminosity of 0.49 nb^{-1}. The azimuthal angle and transverse momentum correlations between the muons are measured as a function of collision centrality. The muon pairs are produced from γγ through the interaction of the large electromagnetic fields of the nuclei. The contribution from background sources of muon pairs is removed using a template fit method. In peripheral collisions, the muons exhibit a strong back-to-back correlation consistent with previous measurements of muon pair production in ultraperipheral collisions. The angular correlations are observed to broaden significantly in central collisions. The modifications are qualitatively consistent with rescattering of the muons while passing through the hot matter produced in the collision.
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37
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Search for Resonant and Nonresonant Higgs Boson Pair Production in the bb[over ¯]τ^{+}τ^{-} Decay Channel in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2018; 121:191801. [PMID: 30468613 DOI: 10.1103/physrevlett.121.191801] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Indexed: 06/09/2023]
Abstract
A search for resonant and nonresonant pair production of Higgs bosons in the bb[over ¯]τ^{+}τ^{-} final state is presented. The search uses 36.1 fb^{-1} of pp collision data with sqrt[s]=13 TeV recorded by the ATLAS experiment at the LHC in 2015 and 2016. Decays of the τ-lepton pairs with at least one τ lepton decaying to final states with hadrons and a neutrino are considered. No significant excess above the expected background is observed in the data. The cross-section times branching ratio for nonresonant Higgs boson pair production is constrained to be less than 30.9 fb, 12.7 times the standard model expectation, at 95% confidence level. The data are also analyzed to probe resonant Higgs boson pair production, constraining a model with an extended Higgs sector based on two doublets and a Randall-Sundrum bulk graviton model. Upper limits are placed on the resonant Higgs boson pair production cross-section times branching ratio, excluding resonances X in the mass range 305 GeV<m_{X}<402 GeV in the simplified hMSSM minimal supersymmetric model for tanβ=2 and excluding bulk Randall-Sundrum gravitons G_{KK} in the mass range 325 GeV<m_{G_{KK}}<885 GeV for k/M[over ¯]_{Pl}=1.
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38
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Performance of missing transverse momentum reconstruction with the ATLAS detector using proton-proton collisions at s = 13 TeV. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:903. [PMID: 30880822 PMCID: PMC6394290 DOI: 10.1140/epjc/s10052-018-6288-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 09/27/2018] [Indexed: 05/07/2023]
Abstract
The performance of the missing transverse momentum ( E T miss ) reconstruction with the ATLAS detector is evaluated using data collected in proton-proton collisions at the LHC at a centre-of-mass energy of 13 TeV in 2015. To reconstruct E T miss , fully calibrated electrons, muons, photons, hadronically decaying τ -leptons , and jets reconstructed from calorimeter energy deposits and charged-particle tracks are used. These are combined with the soft hadronic activity measured by reconstructed charged-particle tracks not associated with the hard objects. Possible double counting of contributions from reconstructed charged-particle tracks from the inner detector, energy deposits in the calorimeter, and reconstructed muons from the muon spectrometer is avoided by applying a signal ambiguity resolution procedure which rejects already used signals when combining the various E T miss contributions. The individual terms as well as the overall reconstructed E T miss are evaluated with various performance metrics for scale (linearity), resolution, and sensitivity to the data-taking conditions. The method developed to determine the systematic uncertainties of the E T miss scale and resolution is discussed. Results are shown based on the full 2015 data sample corresponding to an integrated luminosity of 3.2 fb - 1 .
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39
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Radiosurgery and Checkpoint Blockade Confer Pathologic Complete Response in Mouse Glioblastoma Multiforme with Distinct Immunologic and Radiographic Signatures. Int J Radiat Oncol Biol Phys 2018. [DOI: 10.1016/j.ijrobp.2018.07.739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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40
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Effect of Whole Brain Radiation Therapy on the Absolute Brain Volume Loss. Int J Radiat Oncol Biol Phys 2018. [DOI: 10.1016/j.ijrobp.2018.07.1036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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41
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Measurement of colour flow using jet-pull observables in t t ¯ events with the ATLAS experiment at s = 13 TeV. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:847. [PMID: 30934029 PMCID: PMC6405042 DOI: 10.1140/epjc/s10052-018-6290-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 09/28/2018] [Indexed: 06/09/2023]
Abstract
Previous studies have shown that weighted angular moments derived from jet constituents encode the colour connections between partons that seed the jets. This paper presents measurements of two such distributions, the jet-pull angle and jet-pull magnitude, both of which are derived from the jet-pull angular moment. The measurement is performed in t t ¯ events with one leptonically decaying W boson and one hadronically decaying W boson, using 36.1 fb - 1 of pp collision data recorded by the ATLAS detector ats = 13 TeV delivered by the Large Hadron Collider. The observables are measured for two dijet systems, corresponding to the colour-connected daughters of the W boson and the two b-jets from the top-quark decays, which are not expected to be colour connected. To allow the comparison of the measured distributions to colour model predictions, the measured distributions are unfolded to particle level, after correcting for experimental effects introduced by the detector. While good agreement can be found for some combinations of predictions and observables, none of the predictions describes the data well across all observables.
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42
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Probing the Quantum Interference between Singly and Doubly Resonant Top-Quark Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2018; 121:152002. [PMID: 30362803 DOI: 10.1103/physrevlett.121.152002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 08/06/2018] [Indexed: 06/08/2023]
Abstract
This Letter presents a normalized differential cross-section measurement in a fiducial phase-space region where interference effects between top-quark pair production and associated production of a single top quark with a W boson and a b-quark are significant. Events with exactly two leptons (ee, μμ, or eμ) and two b-tagged jets that satisfy a multiparticle invariant mass requirement are selected from 36.1 fb^{-1} of proton-proton collision data taken at sqrt[s]=13 TeV with the ATLAS detector at the LHC in 2015 and 2016. The results are compared with predictions from simulations using various strategies for the interference. The standard prescriptions for interference modeling are significantly different from each other but are within 2σ of the data. State-of-the-art predictions that naturally incorporate interference effects provide the best description of the data in the measured region of phase space most sensitive to these effects. These results provide an important constraint on interference models and will guide future model development and tuning.
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43
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LO-Phonon Emission Rate of Hot Electrons from an On-Demand Single-Electron Source in a GaAs/AlGaAs Heterostructure. PHYSICAL REVIEW LETTERS 2018; 121:137703. [PMID: 30312059 DOI: 10.1103/physrevlett.121.137703] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Revised: 05/17/2018] [Indexed: 06/08/2023]
Abstract
Using a recent time-of-flight measurement technique with 1 ps time resolution and electron-energy spectroscopy, we develop a method to measure the longitudinal-optical-phonon emission rate of hot electrons traveling along a depleted edge of a quantum Hall bar. Comparison to a single-particle model implies the scattering mechanism involves a two-step process via an intra-Landau-level transition. We show that this can be suppressed by control of the edge potential profile, and a scattering length >1 mm can be achieved, allowing the use of this system for scalable single-electron device applications.
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44
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Prompt and non-prompt J / ψ elliptic flow in Pb+Pb collisions at s NN = 5.02 Tev with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:784. [PMID: 30968860 PMCID: PMC6413499 DOI: 10.1140/epjc/s10052-018-6243-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Accepted: 09/13/2018] [Indexed: 06/09/2023]
Abstract
The elliptic flow of prompt and non-prompt J / ψ was measured in the dimuon decay channel in Pb+Pb collisions ats NN = 5.02 TeV with an integrated luminosity of 0.42 nb - 1 with the ATLAS detector at the LHC. The prompt and non-prompt signals are separated using a two-dimensional simultaneous fit of the invariant mass and pseudo-proper decay time of the dimuon system from the J / ψ decay. The measurement is performed in the kinematic range of dimuon transverse momentum and rapidity 9 < p T < 30 GeV , | y | < 2 , and 0-60% collision centrality. The elliptic flow coefficient, v 2 , is evaluated relative to the event plane and the results are presented as a function of transverse momentum, rapidity and centrality. It is found that prompt and non-prompt J / ψ mesons have non-zero elliptic flow. Prompt J / ψ v 2 decreases as a function of p T , while for non-prompt J / ψ it is, with limited statistical significance, consistent with a flat behaviour over the studied kinematic region. There is no observed dependence on rapidity or centrality.
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45
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Prompt and non-prompt J / ψ and ψ ( 2 S ) suppression at high transverse momentum in 5.02 TeV Pb+Pb collisions with the ATLAS experiment. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:762. [PMID: 30958487 PMCID: PMC6413646 DOI: 10.1140/epjc/s10052-018-6219-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 09/04/2018] [Indexed: 06/09/2023]
Abstract
A measurement of J / ψ and ψ ( 2 S ) production is presented. It is based on a data sample from Pb+Pb collisions at s NN = 5.02 TeV and pp collisions at s = 5.02 TeV recorded by the ATLAS detector at the LHC in 2015, corresponding to an integrated luminosity of 0.42 nb - 1 and 25 pb - 1 in Pb+Pb and pp, respectively. The measurements of per-event yields, nuclear modification factors, and non-prompt fractions are performed in the dimuon decay channel for 9 < p T μ μ < 40 GeV in dimuon transverse momentum, and - 2 < y μ μ < 2 in rapidity. Strong suppression is found in Pb+Pb collisions for both prompt and non-prompt J / ψ , increasing with event centrality. The suppression of prompt ψ ( 2 S ) is observed to be stronger than that of J / ψ , while the suppression of non-prompt ψ ( 2 S ) is equal to that of the non-prompt J / ψ within uncertainties, consistent with the expectation that both arise from b-quarks propagating through the medium. Despite prompt and non-prompt J / ψ arising from different mechanisms, the dependence of their nuclear modification factors on centrality is found to be quite similar.
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46
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Measurements of Higgs boson properties in the diphoton decay channel with
36 fb−1
of
pp
collision data at
s=13 TeV
with the ATLAS detector. Int J Clin Exp Med 2018. [DOI: 10.1103/physrevd.98.052005] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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47
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Search for Higgs bosons produced via vector-boson fusion and decaying into bottom quark pairs in
s=13 TeV
pp
collisions with the ATLAS detector. Int J Clin Exp Med 2018. [DOI: 10.1103/physrevd.98.052003] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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48
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Measurement of the Soft-Drop Jet Mass in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector. PHYSICAL REVIEW LETTERS 2018; 121:092001. [PMID: 30230903 DOI: 10.1103/physrevlett.121.092001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 03/21/2018] [Indexed: 06/08/2023]
Abstract
Jet substructure observables have significantly extended the search program for physics beyond the standard model at the Large Hadron Collider. The state-of-the-art tools have been motivated by theoretical calculations, but there has never been a direct comparison between data and calculations of jet substructure observables that are accurate beyond leading-logarithm approximation. Such observables are significant not only for probing the collinear regime of QCD that is largely unexplored at a hadron collider, but also for improving the understanding of jet substructure properties that are used in many studies at the Large Hadron Collider. This Letter documents a measurement of the first jet substructure quantity at a hadron collider to be calculated at next-to-next-to-leading-logarithm accuracy. The normalized, differential cross section is measured as a function of log_{10}ρ^{2}, where ρ is the ratio of the soft-drop mass to the ungroomed jet transverse momentum. This quantity is measured in dijet events from 32.9 fb^{-1} of sqrt[s]=13 TeV proton-proton collisions recorded by the ATLAS detector. The data are unfolded to correct for detector effects and compared to precise QCD calculations and leading-logarithm particle-level Monte Carlo simulations.
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49
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Search for Low-Mass Dijet Resonances Using Trigger-Level Jets with the ATLAS Detector in pp Collisions at sqrt[s]=13 TeV. PHYSICAL REVIEW LETTERS 2018; 121:081801. [PMID: 30192593 DOI: 10.1103/physrevlett.121.081801] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Indexed: 06/08/2023]
Abstract
Searches for dijet resonances with sub-TeV masses using the ATLAS detector at the Large Hadron Collider can be statistically limited by the bandwidth available to inclusive single-jet triggers, whose data-collection rates at low transverse momentum are much lower than the rate from standard model multijet production. This Letter describes a new search for dijet resonances where this limitation is overcome by recording only the event information calculated by the jet trigger algorithms, thereby allowing much higher event rates with reduced storage needs. The search targets low-mass dijet resonances in the range 450-1800 GeV. The analyzed data set has an integrated luminosity of up to 29.3 fb^{-1} and was recorded at a center-of-mass energy of 13 TeV. No excesses are found; limits are set on Gaussian-shaped contributions to the dijet mass distribution from new particles and on a model of dark-matter particles with axial-vector couplings to quarks.
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50
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Search for new phenomena using the invariant mass distribution of same-flavour opposite-sign dilepton pairs in events with missing transverse momentum in s=13 Tepp collisions with the ATLAS detector. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:625. [PMID: 30215627 PMCID: PMC6129394 DOI: 10.1140/epjc/s10052-018-6081-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 07/16/2018] [Indexed: 06/08/2023]
Abstract
A search for new phenomena in final states containing an e + e - or μ + μ - pair, jets, and large missing transverse momentum is presented. This analysis makes use of proton-proton collision data with an integrated luminosity of 36.1 fb - 1 , collected during 2015 and 2016 at a centre-of-mass energy s = 13 TeV with the ATLAS detector at the Large Hadron Collider. The search targets the pair production of supersymmetric coloured particles (squarks or gluinos) and their decays into final states containing an e + e - or μ + μ - pair and the lightest neutralino ( χ ~ 1 0 ) via one of two next-to-lightest neutralino ( χ ~ 2 0 ) decay mechanisms: χ ~ 2 0 → Z χ ~ 1 0 , where the Z boson decays leptonically leading to a peak in the dilepton invariant mass distribution around the Z boson mass; and χ ~ 2 0 → ℓ + ℓ - χ ~ 1 0 with no intermediate ℓ + ℓ - resonance, yielding a kinematic endpoint in the dilepton invariant mass spectrum. The data are found to be consistent with the Standard Model expectation. Results are interpreted using simplified models, and exclude gluinos and squarks with masses as large as 1.85 and 1.3 Te at 95% confidence level, respectively.
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