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1251 FRAILTY PREVALENCE AND RISK OF SARCOPENIA IN OLDER HEART FAILURE (HF) INPATIENTS. Age Ageing 2023. [DOI: 10.1093/ageing/afac322.044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Abstract
Introduction
Both frailty and HF are common in the elderly population. Elderly HF patients have an increased risk of frailty and elderly frail patients are at a higher risk of developing HF. Frailty is an independent predictor of mortality in cardiovascular disease. Sarcopenia (defined as decreased muscle mass and muscle strength and/or performance) is also prevalent in HF patients and may progress to cardiac cachexia. HF may induce sarcopenia and sarcopenia may contribute to the poor prognosis of HF.
Aims
Methods
A cross-sectional, retrospective analysis of consecutive patients, 60 years and over, admitted with HF to a UK hospital. Data was manually extracted from anonymized electronic records. The Rockwood Clinical Frailty Scale (CFS) was used for assessment for frailty and the SARC-F tool was used for screening for sarcopenia. Patients with medical history of HF but did not present with decompensated HF were excluded. Also, patients with incomplete data were excluded. The IBM SPSS 28 statistical package was used for statistical analysis. Descriptive statistics and risk estimates were calculated.
Results
163 patients were analysed; 82 males and 81 females. The mean age was 81.4 years (SD 9.69). 71.5 % of patients were frail while 28.5 % were non-frail. The risk of sarcopenia was 10.9 times greater in the frail than in the non-frail patients (OR = 10.9; 95% C.I 4.85 – 24.67). There was a lower risk of sarcopenia in male patients than in the female patients (OR =0.45; 95% C.I 0.22 – 0.94).
Conclusions
Frailty is prevalent in older heart failure inpatients. It significantly increases the risk of sarcopenia in these patients. Women are at higher risk of sarcopenia than men. More research is needed into frailty and sarcopenia in.
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1242 CO-MORBIDITY, FRAILTY AND EJECTION FRACTION IN OLDER HEART FAILURE INPATIENTS. Age Ageing 2023. [DOI: 10.1093/ageing/afac322.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Abstract
Introduction
Co-morbidities and frailty are common in older heart failure patients. The aim of this study is to explore the relationship between co-morbidity, frailty and ejection fraction (EF) in older heart failure inpatients
Methods
A cross-sectional, observational, retrospective analysis of consecutive patients aged 60 years and over who were admitted with heart failure in a UK hospital. Patients with incomplete data were excluded. The Carlson’s comorbidity index (CCI) was used to compute comorbidity and the Rockwood Clinical Frailty Scale (CFS) was used to measure frailty. The EF was calculated as the midpoint of the ranges measured by echocardiography. IBM SPSS 28 software was used for statistical analysis. Descriptive statistics were used to measure baseline characteristics and Pearson’s correlation coefficient and linear regression were used to calculate correlation.
Results and discussion
101 patients were analysed; 48 males and 53 females. Mean age was 81.2 years(SD 9.98). Mean CCI was 6.97(SD 1.63) and mean CFS was 5.09(SD 1.14). There was statistically significant positive correlation between CCI and CFS (r= 0.232; p= .01). There was statistically significant inverse correlation between CCI and EF (r= -.277; p=. 005). When taking into account the level of frailty the correlation between CCI and EF was much stronger in non-frail than in frail patients (r= -.612; p=. 035 and r= -.216; p= .047 respectively). There was no correlation between CFS and EF (r= .095; p=.26). This was not surprising as HFpEF is the most common type of HF in the elderly. HFpEF patients are more likely to have more comorbidities and to be more frail compared to HFrEF patients.
Conclusion
There was a positive correlation between multi-morbidity and frailty in older inpatients admitted with heart failure. There was statistically significant inverse correlation between CCI and ejection fraction but there was no correlation between frailty and ejection.
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Designing of multi-epitope vaccine construct employing immuno-informatics approach to combat multi-tick species infestations. EXPLORATORY ANIMAL AND MEDICAL RESEARCH 2022. [DOI: 10.52635/eamr/12.2.149-159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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970 FRAILTY IS INVERSELY CORRELATED WITH SERUM ALBUMIN IN ACUTE HIP FRACTURE. Age Ageing 2022. [DOI: 10.1093/ageing/afac126.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
Introduction
Frailty and sarcopenia have been shown to significantly increase the risk of falls, traumatic hip fractures and all-cause mortality in the elderly. The assessment of frailty using a validated clinical frailty scale such as that proposed by Rockwood et al., therefore, continues to remain an important step in determining post-operative prognosis in patients undergoing hip fracture surgery. The purpose of this study was to examine the relationship between frailty and serum albumin—an independent biochemical predictor of survival in hip fracture patients (1).
Method
This retrospective cross-sectional study analysed 190 patients, aged above 60 years, admitted to Queen’s Hospital Burton (QHB) between the 1st January and 28th December 2019 with a newly diagnosed hip fracture. Pre-operative serum albumin levels (g/L) and Rockwood clinical frailty scores (rCFS) were recorded from electronic medical records (EMR). Using the SPSS 27 statistical package, Pearson’s correlation co-efficient and linear regression analysis were carried out using these variables.
Results
A total of 190 patients were included in the study (57 male, 133 female). Mean patient age was 82.2 ± 8.47 years. More than 50% of patients had a Rockwood CFS ≥5. Mean serum albumin (g/L) was 37.3 ± 6.56. A statistically significant inverse correlation was demonstrated between pre-operative serum albumin levels and Rockwood CFS (r = −0.243, p < 0.001).
Conclusion
This study showed how serum albumin, a negative acute phase reactant and marker of chronic malnutrition, is inversely associated with frailty in hip fracture patients and the important role of Rockwood CFS and pre-operative serum albumin levels in the prognostication of hip fractures in the elderly. References 1) Bohl D, Shen M, Hannon C, Fillingham Y, Darrith B, Della Valle C. Serum Albumin Predicts Survival and Postoperative Course Following Surgery for Geriatric Hip Fracture. Journal of Bone and Joint Surgery. 2017;99(24):2110–2,118.
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975 RELATIONSHIP BETWEEN HAND GRIP STRENGTH (HGS) AND 10 YEAR PROBABILITY OF MAJOR OSTEOPOROTIC FRACTURES IN OLDER. Age Ageing 2022. [DOI: 10.1093/ageing/afac126.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Introduction
HGS has been shown to be associated with adverse outcomes in a wide range of conditions. It has also been found to be associated with bone mineral density and is inversely associated with risk of osteoporotic fractures. The aim of this study was to determine the association between HGS and 10 year probability of sustaining a major osteoporotic fractures in older inpatient and to evaluate the effect of gender on this association.
Method
This was a cross-sectional, observational analysis of older patients admitted into hospital between September and November 2021. HGS was measured in these patients using the JAMAR hydraulic hand held dynamometer. The Southampton protocol was used. The FRAX UK tool (without BMD) was used to calculate 10 year probability of major osteoporotic fractures. Patients were included if they were 60 years and above. Younger patients were excluded as were stroke patients. Patients with incomplete data were excluded from analysis. The SPSS 27 package was used for statistical analysis. Baseline characteristics were calculated using descriptive statistics. Pearson’s correlation coefficient and linear regression were used to calculate correlation.
Results
104 patients were analysed—41 males and 63 females. Mean age was 83 years (SD 8.2). Grip strength was inversely correlated with FRAX UK in predicting 10 year probability of major osteoporotic fractures in all patients, male patients and female patients (r = −0.452; p < 0.001, r = −0.351; p = 0.02 and r = −0.271; p = 0.03 respectively).
Conclusion
Grip strength is negatively associated with increased probability of major osteoporotic fractures in older inpatients. Reference(s) Ma Y, Fu L, Jia L, et al. Muscle strength rather than muscle mass is associated with osteoporosis in older Chinese adults. J Formos Med Assoc. 2018;117(2):101–108. doi:10.1016/j.jfma.2017.03.004
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974 ASSOCIATION BETWEEN NOTTINGHAM HIP FRACTURE SCORE AND FRAILTY IN ELDERLY ACUTE HIP FRACTURE PATIENTS. Age Ageing 2022. [DOI: 10.1093/ageing/afac126.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Introduction
Nottingham Hip Fracture Score (NHFS) is a well validated risk stratification tool that has been shown to predict 30 day mortality in elderly patients with acute hip fractures. A lot of older patients that sustain hip fractures are frail. The Rockwood Clinical Frailty Scale (CFS) has been validated as a tool to screen for frailty in acutely ill patients and has been shown to predict outcomes in acutely ill elderly patients. The aim of this study was to determine if there is any correlation between the NHFS and CFS in elderly patients with acute hip fractures and to evaluate the effect of gender on this correlation.
Method
A retrospective, cross-sectional analysis was carried out on patients admitted with acute hip fractures between January and December 2019 in a single centre trauma and orthopaedic unit. Data was extracted from anonymized electronic patient records. Patients were included if they were 60 years and above; those less than 60 were excluded. Patients with missing data were excluded from analysis. NHFS and CFS were calculated in these patients. SPSS 27 IBM software was used for statistical analysis. Baseline characteristics were calculated using descriptive statistics and spearman’s correlation co-efficient and linear regression were used to determine correlation.
Results
A total of 268 patients were analysed—65 males and 202 females. Mean age was 83 years (SD 8.5). There was statistically significant positive correlation between NHFS and CFS in all patients, male patients and female patients (r = 0.589; p < 0.001, r = 0.603; p < 0.001, and r = 0.599; p < 0.001 respectively).
Conclusion
NHFS is positively correlated with CFS in elderly acute hip fracture patients. Reference(s) Doherty W.J, Stubbs T.A et al. Prediction of Postoperative Outcomes Following Hip Fracture Surgery: Independent Validation and Recalibration of the Nottingham Hip Fracture Score. Journal of the American Medical Directors Association;22(3):663–669.e2.
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E-learning in formal education under forced conditions using SDT and TAM. CARDIOMETRY 2022. [DOI: 10.18137/cardiometry.2022.22.268276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
This study aims to understand the students’ attitude towards e-learning under the forced environment of the COVID-19 pandemic. This study gives a fresh insight into e-learning, considering the lack of comprehensive research on the influencing variables that impact the user acceptance of e-learning by learners in the Indian Universities during COVID-19 pandemic. The rational model has been constituted based on the Technological Acceptance Model (TAM) and Self-Determination Theory (SDT) to study the effective influence of Autonomy, Relatedness & Competency on the construct of TAM. The result showed significant relations of the self-determination variables with perceived ease of use & perceived usefulness, which further helps us establish a relationship between intrinsic & extrinsic factors of SDT framework with attitude and satisfaction level of Indian University students towards e-learning. This study will assist in bridging the gap between the understanding of organizations and actual factors impacting students’ learning process during the pandemic of COVID-19.
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Altered electrochemical properties of iron oxide nanoparticles by carbon enhance molecular biocompatibility through discrepant atomic interaction. Mater Today Bio 2021; 12:100131. [PMID: 34622194 PMCID: PMC8479829 DOI: 10.1016/j.mtbio.2021.100131] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 08/23/2021] [Accepted: 08/31/2021] [Indexed: 12/23/2022] Open
Abstract
Recent advancement in nanotechnology seeks exploration of new techniques for improvement in the molecular, chemical, and biological properties of nanoparticles. In this study, carbon modification of octahedral-shaped magnetic nanoparticles (MNPs) was done using two-step chemical processes with sucrose as a carbon source for improvement in their electrochemical application and higher molecular biocompatibility. X-ray diffraction analysis and electron microscopy confirmed the alteration in single-phase octahedral morphology and carbon attachment in Fe3O4 structure. The magnetization saturation and BET surface area for Fe3O4, Fe3O4/C, and α-Fe2O3/C were measured as 90, 86, and 27 emu/g and 16, 56, and 89 m2/g with an average pore size less than 7 nm. Cyclic voltammogram and galvanostatic charge/discharge studies showed the highest specific capacitance of carbon-modified Fe3O4 and α-Fe2O3 as 213 F/g and 192 F/g. The in vivo biological effect of altered physicochemical properties of Fe3O4 and α-Fe2O3 was assessed at the cellular and molecular level with embryonic zebrafish. Mechanistic in vivo toxicity analysis showed a reduction in oxidative stress in carbon-modified α-Fe2O3 exposed zebrafish embryos compared to Fe3O4 due to despaired influential atomic interaction with sod1 protein along with significant less morphological abnormalities and apoptosis. The study provided insight into improving the characteristic of MNPs for electrochemical application and higher biological biocompatibility.
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Ethnic disparities in health & social care workers’ exposure, protection, and clinical management of the COVID-19 pandemic in the UK. CRITICAL PUBLIC HEALTH 2021. [DOI: 10.1080/09581596.2021.1959020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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537 AGE, FRAILTY AND COMORBIDITY IN COVID-19 INPATIENTS 65 AND OLDER. Age Ageing 2021. [PMCID: PMC8344498 DOI: 10.1093/ageing/afab119.17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Introduction
Higher incidence of COVID-19 and poorer outcomes have been shown to be associated with age, frailty and comorbidity. Older people have more risk of severe COVID 19; hospitalization, ITU admission, ventilation and mortality.
Aim
To assess the correlation between age, frailty and comorbidity in COVID-19 inpatients 65 years and older.
Methods
A retrospective, cross-sectional analysis was carried out on COVID 19 inpatients 65 and older in a UK district general hospital. Patients with no microbiological evidence of COVID-19 and patients with incomplete data were excluded from the study. Demographic data, frailty score and comorbidity index were extracted from the electronic records of patients. SPSS 27 statistical software was used to perform descriptive analysis and linear regression coefficient.
Results
357 COVID-19 patients 65 and over were assessed; 207 males and 150 females. Mean age was 81.9 +/− 9.31. Frailty scores were measured using the Rockwood Clinical Frailty Scale (CFS) and comorbidity was calculated using the Charlson Comorbidity Index (CCI). There was positive correlation between age and Clinical Frailty Scale (r=. 436; p<. 001), between age and Charlson Comorbidity Index (r=. 448; p<. 001, and between frailty and comorbidity (r=. 429; p<. 001).
Conclusion
In COVID-19 inpatients 65 and older, there was positive correlation between age and Clinical Frailty Scale, between age and Charlson Comorbidity Index and between frailty and comorbidity. More studies are needed to explore the interaction between age, frailty and comorbidity and COVID 19 morbidity and mortality.
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152 The Relationship Between 25(OH) Vitamin D and Bone Mineral Density (BMD) in Patients 65 Years and Older with Prior Fragility Fractures. Age Ageing 2021. [DOI: 10.1093/ageing/afab030.113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Introduction
25(OH) vitamin D [25(OH) D] levels are known to influence skeletal health as well as muscle function. Some studies suggest a positive association between 25(OH) D levels and BMD at various skeletal sites in men but not in women. These findings were mostly observed in younger (less than 50 year old) cohorts. Evidence for this association in older patients with prior fragility fractures is lacking. Aim: To assess the correlation of 25(OH) D levels with T-scores at the neck of femur, hip and spine in patients 65 years and older with prior fragility fractures and the effect of gender on the correlation.
Methods
A retrospective, cross-sectional analysis of patients 65 and older with previous fragility fractures in patients attending a fracture prevention service. Data was extracted from the electronic records. SPSS 26 statistical software was used for statistical analysis. Pearson correlation coefficient was used to calculate correlation and regression coefficient for gender.
Results
151 patients were included; 26 males and 126 females. Mean age was 76.2 and 74.1 years respectively. In the males there was good positive, statistically significant correlation between the 25(OH) D and T-scores at the neck of femur (r = 0.415; p < 0.05) and hip (r = 0.413; p < 0.05), but correlation with T-score of the spine was not statistically significant (r = 0.349; p = 0.103). In the females there was no statistically significant correlation between 25(OH) D and T-scores at the neck of femur, hip or spine (r = 0.163; p = 0.077), (r = 0.096; p = 0.299) and (r = 0.114; p = 0.217) respectively.
Conclusion
In males, 65 years and older, with prior fragility fracture, there is a positive significant correlation between 25(OH) D and BMD at the neck of femur and hip whereas there is no significant correlation in females.
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93 Does Spinal Bone Mineral Density Predict An Absolute 10 Year Probability of Sustaining A Major Osteoporotic Fracture. Age Ageing 2021. [DOI: 10.1093/ageing/afab030.54] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Introduction
Spine and hip bone mineral density (BMD) have previously been shown to predict the risk of sustaining future fractures. Although these have been shown in population studies, there is a paucity of trials looking at the relationship between BMD and 10 year probability of major osteoporotic fractures (Using FRAX UK without BMD) in patients with previous fragility fractures.
Aims
To evaluate the correlation between spinal T-score and an absolute 10 year probability of sustaining a major osteoporotic fracture (using FRAX without BMD) in patients with prior fragility fractures.
Methods
A retrospective cross-sectional analysis of 202 patients (29 males and 173 females) with prior fragility fractures attending a fracture prevention clinic between January and August 2019 was performed. Patients with pathological and high impact traumatic fractures were excluded. The BMD at the spine was determined using the lowest T-score of the vertebrae from L1 to L4. Using the FRAX (UK) without BMD, the absolute 10 year probability of sustaining a major osteoporotic fracture was calculated for each patient. Statistical analysis was performed using SPSS 26 software.
Results
The mean T-score at the spine was −1.15 (SD +/− 1.90) for all patients, −0.68 (SD +/− 0.45) for males and − 1.23 (SD +/− 0.14) for females. The mean FRAX score without BMD for major osteoporotic fracture was 18.5% (SD +/− 8.84) for all patients, 11.41% (SD +/−0.62) and 19.7% (SD +/−0.68) for males and females respectively. Pearson correlation coefficient showed a statistically significant, slightly negative correlation between spinal T- score and the FRAX (UK) without BMD (r = −0.157; p < 0.05). Correlation was not statistically significant when males (r = 0.109; p = 0.59) and females (r = 0.148; p = 0.053) were considered independently.
Conclusion
In patients with prior fragility fracture spinal BMD has a statistically significant negative correlation with an absolute 10 year probability of sustaining a major osteoporotic fracture.
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153 Age and the Extent of Chest Radiographic Findings in Hospitalized Patients with COVID 19. Age Ageing 2021. [PMCID: PMC7989602 DOI: 10.1093/ageing/afab030.114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Introduction
Since the emergence of COVID 19 in December 2019, its clinical and radiological features are still being discovered and their prognostic implications evaluated. Chest X-ray (CXR) typically shows patchy or diffuse asymmetric airspace opacities. Regardless of the different classifications of radiological findings that have been used, it is becoming clear that multi-lobar changes in the lungs are associated with poorer outcomes than single lobar involvement or minimal/no radiological abnormalities.
Aim: To assess the correlation of age with the extent of CXR findings in hospitalized COVID 19 patients.
Methods
A retrospective, cross-sectional analysis was carried out on inpatients with RT-PCR confirmed COVID 19. Chest X-ray findings were classified as minimal/no radiological changes, single lobar opacification and multi-lobar changes (involving 2 or more lobes and/or ARDS changes). SPSS 26 software was used for statistical analysis. Spearman’s correlation and linear regression were used to assess correlation.
Results
211 patients were included in the analysis; 124 males and 87 females. Mean age of the patients was 72.4 years; SD +/−16.15. There was significant positive correlation between age and degree and extent of radiological changes in all patients (r = 0.367; p < 0.01). This correlation persisted even when broken down by gender (r = 0.448; p < 0.01) for males and (r = 0.322; p < 0.01) for females. Discussion: Older age has been repeatedly reported as a risk factor for poor prognosis in COVID 19. The main findings of COVID-19 on CXR are those of atypical or organizing pneumonia. Older people tend to have more extensive involvement of the lungs. There could be many explanations for the CXR correlation with age including the diminished cardiovascular reserve with ageing, the accumulation of comorbidities and decreased or abnormal immune response.
Conclusion
Age significantly correlate with the extent of chest radiographic findings in inpatients with COVID 19.
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Constraints on the K_{S}^{0}→μ^{+}μ^{-} Branching Fraction. PHYSICAL REVIEW LETTERS 2020; 125:231801. [PMID: 33337231 DOI: 10.1103/physrevlett.125.231801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 09/25/2020] [Indexed: 06/12/2023]
Abstract
A search for the decay K_{S}^{0}→μ^{+}μ^{-} is performed using proton-proton collision data, corresponding to an integrated luminosity of 5.6 fb^{-1} and collected with the LHCb experiment during 2016, 2017, and 2018 at a center-of-mass energy of 13 TeV. The observed signal yield is consistent with zero, yielding an upper limit of B(K_{S}^{0}→μ^{+}μ^{-})<2.2×10^{-10} at 90% C.L.. The limit reduces to B(K_{S}^{0}→μ^{+}μ^{-})<2.1×10^{-10} at 90% C.L. once combined with the result from data taken in 2011 and 2012.
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Association of vitamin D with fatty acids in pregnancy. Prostaglandins Leukot Essent Fatty Acids 2020; 157:102030. [PMID: 31753523 DOI: 10.1016/j.plefa.2019.102030] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Accepted: 11/05/2019] [Indexed: 12/24/2022]
Abstract
Preeclampsia is a pregnancy complication, associated with an increased risk of maternal and neonatal morbidity and mortality. The etiology of preeclampsia is not yet fully understood, although the current literature indicates an up regulation of inflammatory mediators. Vitamin D is known to have anti-inflammatory properties and influence vascular function. Fatty acids are also known to regulate inflammation in pregnancy. This study was carried out to explore the association of maternal vitamin D and fatty acids in pregnancy. The present study includes 69 normotensive control (NC) and 50 women with preeclampsia (PE). Maternal and cord serum 25-hydroxyvitamin D [25(OH)D] levels were lower (p<0.01for both) in women with PE compared to NC women. Maternal plasma total polyunsaturated fatty acids (PUFA) levels were lower (p<0.05) while levels of total saturated fatty acids (SFA) and total monounsaturated fatty acids (MUFA) were higher (p<0.05 for both) in women with PE. Cord erythrocyte PUFA levels were higher (p<0.01) in PE women. Maternal 25(OH)D levels were negatively associated with maternal systolic and diastolic BP (p<0.01 for both). Maternal 25(OH)D levels were positively associated with maternal total PUFA (p<0.01) and negatively associated with maternal total SFA (p<0.05), total MUFA (p<0.01). This study for the first time demonstrates an association of maternal vitamin D with fatty acid levels in pregnancy. Our results suggest that vitamin D and fatty acids may work in concert to regulate fetal growth.
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Measurement of f_{s}/f_{u} Variation with Proton-Proton Collision Energy and B-Meson Kinematics. PHYSICAL REVIEW LETTERS 2020; 124:122002. [PMID: 32281875 DOI: 10.1103/physrevlett.124.122002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 12/13/2019] [Accepted: 03/02/2020] [Indexed: 06/11/2023]
Abstract
The ratio of the B_{s}^{0} and B^{+} fragmentation fractions f_{s} and f_{u} is studied with B_{s}^{0}→J/ψϕ and B^{+}→J/ψK^{+} decays using data collected by the LHCb experiment in proton-proton collisions at 7, 8, and 13 TeV center-of-mass energies. The analysis is performed in bins of B-meson momentum, longitudinal momentum, transverse momentum, pseudorapidity, and rapidity. The fragmentation-fraction ratio f_{s}/f_{u} is observed to depend on the B-meson transverse momentum with a significance of 6.0σ. This dependency is driven by the 13 TeV sample (8.7σ), while the results for the other collision energies are not significant when considered separately. Furthermore, the results show a 4.8σ evidence for an increase of f_{s}/f_{u} as a function of collision energy.
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Isospin Amplitudes in Λ_{b}^{0}→J/ψΛ(Σ^{0}) and Ξ_{b}^{0}→J/ψΞ^{0}(Λ) Decays. PHYSICAL REVIEW LETTERS 2020; 124:111802. [PMID: 32242683 DOI: 10.1103/physrevlett.124.111802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 01/08/2020] [Accepted: 02/14/2020] [Indexed: 06/11/2023]
Abstract
Ratios of isospin amplitudes in hadron decays are a useful probe of the interplay between weak and strong interactions and allow searches for physics beyond the standard model. We present the first results on isospin amplitudes in b-baryon decays, using data corresponding to an integrated luminosity of 8.5 fb^{-1}, collected with the LHCb detector in pp collisions at center of mass energies of 7, 8, and 13 TeV. The isospin amplitude ratio |A_{1}(Λ_{b}^{0}→J/ψΣ^{0})/A_{0}(Λ_{b}^{0}→J/ψΛ)|, where the subscript on A indicates the final-state isospin, is measured to be less than 1/21.8 at 95% confidence level. The Cabibbo suppressed Ξ_{b}^{0}→J/ψΛ decay is observed for the first time, allowing for the measurement |A_{0}(Ξ_{b}^{0}→J/ψΛ)/A_{1/2}(Ξ_{b}^{0}→J/ψΞ^{0})|=0.37±0.06±0.02, where the uncertainties are statistical and systematic, respectively.
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The effect of gender inequality on HIV incidence in Sub-Saharan Africa. Public Health 2020; 182:56-63. [PMID: 32179289 DOI: 10.1016/j.puhe.2020.01.014] [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: 09/22/2019] [Revised: 01/16/2020] [Accepted: 01/23/2020] [Indexed: 11/16/2022]
Abstract
OBJECTIVE We aimed to quantify the extent to which country-level trends in HIV incidence in Sub-Saharan Africa (SSA) were influenced by gender inequalities, measured by gender gaps in educational attainment, income, and a Gender Inequality Index (GII). STUDY DESIGN We examined the relation between gender inequality and HIV incidence using country-level panel data from 24 SSA countries for the period between 2000 and 2016. METHODS Our goal was to estimate the relation between within-country changes in gender inequality and HIV incidence. We compared results from fixed effects and random effects models for estimating the effect of gender inequalities on changes in HIV incidence. Based on the results of the Hausman test, the fixed effects model was selected as the preferred approach. RESULTS HIV incidence decreased by nearly one-half over the period from 2000 to 2016. We estimated that a one percent increase in the GII was associated with a 1.6 percent increase in HIV incidence (95% confidence interval = [0.21%; 3.00%]), after adjusting by country-level socio-economic and governance variables. CONCLUSIONS Our study suggests that addressing gender inequalities is a potential strategy to reduce HIV incidence in the SSA region. To control HIV infection, policymakers and public health practitioners should support relevant interventions for promoting gender equality. Further work is needed to identify specific interventions to improve gender inequality and to examine their impacts on changes in HIV incidence.
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First Observation of Excited Ω_{b}^{-} States. PHYSICAL REVIEW LETTERS 2020; 124:082002. [PMID: 32167334 DOI: 10.1103/physrevlett.124.082002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 02/03/2020] [Indexed: 06/10/2023]
Abstract
We report four narrow peaks in the Ξ_{b}^{0}K^{-} mass spectrum obtained using pp collisions at center-of-mass energies of 7, 8, and 13 TeV, corresponding to a total integrated luminosity of 9 fb^{-1} recorded by the LHCb experiment. Referring to these states by their mass, the mass values are m[Ω_{b}(6316)^{-}]=6315.64±0.31±0.07±0.50 MeV, m[Ω_{b}(6330)^{-}]=6330.30±0.28±0.07±0.50 MeV, m[Ω_{b}(6340)^{-}]=6339.71±0.26±0.05±0.50 MeV, m[Ω_{b}(6350)^{-}]=6349.88±0.35±0.05±0.50 MeV, where the uncertainties are statistical, systematic, and the last is due to the knowledge of the Ξ_{b}^{0} mass. The natural widths of the three lower mass states are consistent with zero, and the 90% confidence-level upper limits are determined to be Γ[Ω_{b}(6316)^{-}]<2.8 MeV, Γ[Ω_{b}(6330)^{-}]<3.1 MeV and Γ[Ω_{b}(6340)^{-}]<1.5 MeV. The natural width of the Ω_{b}(6350)^{-} peak is 1.4_{-0.8}^{+1.0}±0.1 MeV, which is 2.5σ from zero and corresponds to an upper limit of 2.8 MeV. The peaks have local significances ranging from 3.6σ to 7.2σ. After accounting for the look-elsewhere effect, the significances of the Ω_{b}(6316)^{-} and Ω_{b}(6330)^{-} peaks are reduced to 2.1σ and 2.6σ, respectively, while the two higher mass peaks exceed 5σ. The observed peaks are consistent with expectations for excited Ω_{b}^{-} resonances.
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20
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Search for A^{'}→μ^{+}μ^{-} Decays. PHYSICAL REVIEW LETTERS 2020; 124:041801. [PMID: 32058729 DOI: 10.1103/physrevlett.124.041801] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 12/12/2019] [Indexed: 06/10/2023]
Abstract
Searches are performed for both promptlike and long-lived dark photons, A^{'}, produced in proton-proton collisions at a center-of-mass energy of 13 TeV. These searches look for A^{'}→μ^{+}μ^{-} decays using a data sample corresponding to an integrated luminosity of 5.5 fb^{-1} collected with the LHCb detector. Neither search finds evidence for a signal, and 90% confidence-level exclusion limits are placed on the γ-A^{'} kinetic mixing strength. The promptlike A^{'} search explores the mass region from near the dimuon threshold up to 70 GeV and places the most stringent constraints to date on dark photons with 214<m(A^{'})≲740 MeV and 10.6<m(A^{'})≲30 GeV. The search for long-lived A^{'}→μ^{+}μ^{-} decays places world-leading constraints on low-mass dark photons with lifetimes O(1) ps.
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21
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Observation of Several Sources of CP Violation in B^{+}→π^{+}π^{+}π^{-} Decays. PHYSICAL REVIEW LETTERS 2020; 124:031801. [PMID: 32031835 DOI: 10.1103/physrevlett.124.031801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Indexed: 06/10/2023]
Abstract
Observations are reported of different sources of CP violation from an amplitude analysis of B^{+}→π^{+}π^{+}π^{-} decays, based on a data sample corresponding to an integrated luminosity of 3 fb^{-1} of pp collisions recorded with the LHCb detector. A large CP asymmetry is observed in the decay amplitude involving the tensor f_{2}(1270) resonance, and in addition significant CP violation is found in the π^{+}π^{-}S wave at low invariant mass. The presence of CP violation related to interference between the π^{+}π^{-}S wave and the P wave B^{+}→ρ(770)^{0}π^{+} amplitude is also established; this causes large local asymmetries but cancels when integrated over the phase space of the decay. The results provide both qualitative and quantitative new insights into CP -violation effects in hadronic B decays.
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22
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Search for Lepton-Flavor Violating Decays B^{+}→K^{+}μ^{±}e^{∓}. PHYSICAL REVIEW LETTERS 2019; 123:241802. [PMID: 31922836 DOI: 10.1103/physrevlett.123.241802] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Indexed: 06/10/2023]
Abstract
A search for the lepton-flavor violating decays B^{+}→K^{+}μ^{±}e^{∓} is performed using a sample of proton-proton collision data, collected with the LHCb experiment at center-of-mass energies of 7 and 8 TeV and corresponding to an integrated luminosity of 3 fb^{-1}. No significant signal is observed, and upper limits on the branching fractions are set as B(B^{+}→K^{+}μ^{-}e^{+})<7.0(9.5)×10^{-9} and B(B^{+}→K^{+}μ^{+}e^{-})<6.4(8.8)×10^{-9} at 90% (95)% confidence level. The results improve the current best limits on these decays by more than one order of magnitude.
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23
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Measurement of Charged Hadron Production in Z-Tagged Jets in Proton-Proton Collisions at sqrt[s]=8 TeV. PHYSICAL REVIEW LETTERS 2019; 123:232001. [PMID: 31868452 DOI: 10.1103/physrevlett.123.232001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 06/13/2019] [Indexed: 06/10/2023]
Abstract
The production of charged hadrons within jets recoiling against a Z boson is measured in proton-proton collision data at sqrt[s]=8 TeV recorded by the LHCb experiment. The charged-hadron structure of the jet is studied longitudinally and transverse to the jet axis for jets with transverse momentum p_{T}>20 GeV and in the pseudorapidity range 2.5<η<4. These are the first measurements of jet hadronization at these forward rapidities and also the first where the jet is produced in association with a Z boson. In contrast to previous hadronization measurements at the Large Hadron Collider, which are dominated by gluon jets, these measurements probe predominantly light-quark jets which are found to be more longitudinally and transversely collimated with respect to the jet axis when compared to the previous gluon dominated measurements. Therefore, these results provide valuable information on differences between quarks and gluons regarding nonperturbative hadronization dynamics.
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Amplitude Analysis of B^{±}→π^{±}K^{+}K^{-} Decays. PHYSICAL REVIEW LETTERS 2019; 123:231802. [PMID: 31868437 DOI: 10.1103/physrevlett.123.231802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 10/15/2019] [Indexed: 06/10/2023]
Abstract
The first amplitude analysis of the B^{±}→π^{±}K^{+}K^{-} decay is reported based on a data sample corresponding to an integrated luminosity of 3.0 fb^{-1} of pp collisions recorded in 2011 and 2012 with the LHCb detector. The data are found to be best described by a coherent sum of five resonant structures plus a nonresonant component and a contribution from ππ↔KK S-wave rescattering. The dominant contributions in the π^{±} K^{∓} and K^{+} K^{-} systems are the nonresonant and the B^{±}→ρ(1450)^{0}π^{±} amplitudes, respectively, with fit fractions around 30%. For the rescattering contribution, a sizable fit fraction is observed. This component has the largest CP asymmetry reported to date for a single amplitude of (-66±4±2)%, where the first uncertainty is statistical and the second systematic. No significant CP violation is observed in the other contributions.
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Search for the Lepton-Flavor-Violating Decays B_{s}^{0}→τ^{±}μ^{∓} and B^{0}→τ^{±}μ^{∓}. PHYSICAL REVIEW LETTERS 2019; 123:211801. [PMID: 31809134 DOI: 10.1103/physrevlett.123.211801] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Indexed: 06/10/2023]
Abstract
Results are reported from a search for the rare decays B_{s}^{0}→τ^{±}μ^{∓} and B^{0}→τ^{±}μ^{∓}, where the τ lepton is reconstructed in the channel τ^{-}→π^{-}π^{+}π^{-}ν_{τ}. These processes are effectively forbidden in the standard model, but they can potentially occur at detectable rates in models of new physics that can induce lepton-flavor-violating decays. The search is based on a data sample corresponding to 3 fb^{-1} of proton-proton collisions recorded by the LHCb experiment in 2011 and 2012. The event yields observed in the signal regions for both processes are consistent with the expected standard model backgrounds. Because of the limited mass resolution arising from the undetected τ neutrino, the B_{s}^{0} and B^{0} signal regions are highly overlapping. Assuming no contribution from B^{0}→τ^{±}μ^{∓}, the upper limit B(B_{s}^{0}→τ^{±}μ^{∓})<4.2×10^{-5} is obtained at 95% confidence level. If no contribution from B_{s}^{0}→τ^{±}μ^{∓} is assumed, a limit of B(B^{0}→τ^{±}μ^{∓})<1.4×10^{-5} is obtained at 95% confidence level. These results represent the first limit on B(B_{s}^{0}→τ^{±}μ^{∓}) and the most stringent limit on B(B^{0}→τ^{±}μ^{∓}).
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Observation of New Resonances in the Λ_{b}^{0}π^{+}π^{-} System. PHYSICAL REVIEW LETTERS 2019; 123:152001. [PMID: 31702304 DOI: 10.1103/physrevlett.123.152001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 08/27/2019] [Indexed: 06/10/2023]
Abstract
We report the observation of a new structure in the Λ_{b}^{0}π^{+}π^{-} spectrum using the full LHCb data set of pp collisions, corresponding to an integrated luminosity of 9 fb^{-1}, collected at sqrt[s]=7, 8, and 13 TeV. A study of the structure suggests its interpretation as a superposition of two almost degenerate narrow states. The masses and widths of these states are measured to be m_{Λ_{b}(6146)^{0}}=6146.17±0.33±0.22±0.16 MeV,m_{Λ_{b}(6152)^{0}}=6152.51±0.26±0.22±0.16 MeV,Γ_{Λ_{b}(6146)^{0}}=2.9±1.3±0.3 MeV,Γ_{Λ_{b}(6152)^{0}}=2.1±0.8±0.3 MeV,with a mass splitting of Δm=6.34±0.32±0.02 MeV, where the first uncertainty is statistical, the second systematic. The third uncertainty for the mass measurements derives from the knowledge of the mass of the Λ_{b}^{0} baryon. The measured masses and widths of these new excited states suggest their possible interpretation as a doublet of Λ_{b}(1D)^{0} states.
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28
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Measurement of CP-Violating and Mixing-Induced Observables in B_{s}^{0}→ϕγ Decays. PHYSICAL REVIEW LETTERS 2019; 123:081802. [PMID: 31491228 DOI: 10.1103/physrevlett.123.081802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Indexed: 06/10/2023]
Abstract
A time-dependent analysis of the B_{s}^{0}→ϕγ decay rate is performed to determine the CP -violating observables S_{ϕγ} and C_{ϕγ} and the mixing-induced observable A_{ϕγ}^{Δ}. The measurement is based on a sample of pp collision data recorded with the LHCb detector, corresponding to an integrated luminosity of 3 fb^{-1} at center-of-mass energies of 7 and 8 TeV. The measured values are S_{ϕγ}=0.43±0.30±0.11, C_{ϕγ}=0.11±0.29±0.11, and A_{ϕγ}^{Δ}=-0.67_{-0.41}^{+0.37}±0.17, where the first uncertainty is statistical and the second systematic. This is the first measurement of the observables S and C in radiative B_{s}^{0} decays. The results are consistent with the standard model predictions.
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29
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First Observation of the Radiative Decay Λ_{b}^{0}→Λγ. PHYSICAL REVIEW LETTERS 2019; 123:031801. [PMID: 31386473 DOI: 10.1103/physrevlett.123.031801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Indexed: 06/10/2023]
Abstract
The radiative decay Λ_{b}^{0}→Λγ is observed for the first time using a data sample of proton-proton collisions corresponding to an integrated luminosity of 1.7 fb^{-1} collected by the LHCb experiment at a center-of-mass energy of 13 TeV. Its branching fraction is measured exploiting the B^{0}→K^{*0}γ decay as a normalization mode and is found to be B(Λ_{b}^{0}→Λγ)=(7.1±1.5±0.6±0.7)×10^{-6}, where the quoted uncertainties are statistical, systematic, and systematic from external inputs, respectively. This is the first observation of a radiative decay of a beauty baryon.
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30
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Observation of an Excited B_{c}^{+} State. PHYSICAL REVIEW LETTERS 2019; 122:232001. [PMID: 31298897 DOI: 10.1103/physrevlett.122.232001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 04/23/2019] [Indexed: 06/10/2023]
Abstract
Using pp collision data corresponding to an integrated luminosity of 8.5 fb^{-1} recorded by the LHCb experiment at center-of-mass energies of sqrt[s]=7, 8, and 13 TeV, the observation of an excited B_{c}^{+} state in the B_{c}^{+}π^{+}π^{-} invariant-mass spectrum is reported. The observed peak has a mass of 6841.2±0.6(stat)±0.1(syst)±0.8(B_{c}^{+}) MeV/c^{2}, where the last uncertainty is due to the limited knowledge of the B_{c}^{+} mass. It is consistent with expectations of the B_{c}^{*}(2^{3}S_{1})^{+} state reconstructed without the low-energy photon from the B_{c}^{*}(1^{3}S_{1})^{+}→B_{c}^{+}γ decay following B_{c}^{*}(2^{3}S_{1})^{+}→B_{c}^{*}(1^{3}S_{1})^{+}π^{+}π^{-}. A second state is seen with a global (local) statistical significance of 2.2σ (3.2σ) and a mass of 6872.1±1.3(stat)±0.1(syst)±0.8(B_{c}^{+}) MeV/c^{2}, and is consistent with the B_{c}(2^{1}S_{0})^{+} state. These mass measurements are the most precise to date.
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31
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Measurement of the Mass Difference Between Neutral Charm-Meson Eigenstates. PHYSICAL REVIEW LETTERS 2019; 122:231802. [PMID: 31298908 DOI: 10.1103/physrevlett.122.231802] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Indexed: 06/10/2023]
Abstract
We report a measurement of the mass difference between neutral charm-meson eigenstates using a novel approach that enhances sensitivity to this parameter. We use 2.3×10^{6} D^{0}→K_{S}^{0}π^{+}π^{-} decays reconstructed in proton-proton collisions collected by the LHCb experiment in 2011 and 2012. Allowing for CP violation in mixing and in the interference between mixing and decay, we measure the CP-averaged normalized mass difference x_{CP}=[2.7±1.6(stat)±0.4(syst)]×10^{-3} and the CP-violating parameter Δx=[-0.53±0.70(stat)±0.22(syst)]×10^{-3}. The results are consistent with CP symmetry. These determinations are the most precise from a single experiment and, combined with current world-average results, yield the first evidence that the masses of the neutral charm-meson eigenstates differ.
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32
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Observation of a Narrow Pentaquark State, P_{c}(4312)^{+}, and of the Two-Peak Structure of the P_{c}(4450)^{+}. PHYSICAL REVIEW LETTERS 2019; 122:222001. [PMID: 31283265 DOI: 10.1103/physrevlett.122.222001] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Indexed: 06/09/2023]
Abstract
A narrow pentaquark state, P_{c}(4312)^{+}, decaying to J/ψp, is discovered with a statistical significance of 7.3σ in a data sample of Λ_{b}^{0}→J/ψpK^{-} decays, which is an order of magnitude larger than that previously analyzed by the LHCb Collaboration. The P_{c}(4450)^{+} pentaquark structure formerly reported by LHCb is confirmed and observed to consist of two narrow overlapping peaks, P_{c}(4440)^{+} and P_{c}(4457)^{+}, where the statistical significance of this two-peak interpretation is 5.4σ. The proximity of the Σ_{c}^{+}D[over ¯]^{0} and Σ_{c}^{+}D[over ¯]^{*0} thresholds to the observed narrow peaks suggests that they play an important role in the dynamics of these states.
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33
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Observation of CP Violation in Charm Decays. PHYSICAL REVIEW LETTERS 2019; 122:211803. [PMID: 31283320 DOI: 10.1103/physrevlett.122.211803] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 05/02/2019] [Indexed: 06/09/2023]
Abstract
A search for charge-parity (CP) violation in D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays is reported, using pp collision data corresponding to an integrated luminosity of 5.9 fb^{-1} collected at a center-of-mass energy of 13 TeV with the LHCb detector. The flavor of the charm meson is inferred from the charge of the pion in D^{*}(2010)^{+}→D^{0}π^{+} decays or from the charge of the muon in B[over ¯]→D^{0}μ^{-}ν[over ¯]_{μ}X decays. The difference between the CP asymmetries in D^{0}→K^{-}K^{+} and D^{0}→π^{-}π^{+} decays is measured to be ΔA_{CP}=[-18.2±3.2(stat)±0.9(syst)]×10^{-4} for π-tagged and ΔA_{CP}=[-9±8(stat)±5(syst)]×10^{-4} for μ-tagged D^{0} mesons. Combining these with previous LHCb results leads to ΔA_{CP}=(-15.4±2.9)×10^{-4}, where the uncertainty includes both statistical and systematic contributions. The measured value differs from zero by more than 5 standard deviations. This is the first observation of CP violation in the decay of charm hadrons.
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Search for CP Violation in D_{s}^{+}→K_{S}^{0}π^{+}, D^{+}→K_{S}^{0}K^{+}, and D^{+}→ϕπ^{+} Decays. PHYSICAL REVIEW LETTERS 2019; 122:191803. [PMID: 31144928 DOI: 10.1103/physrevlett.122.191803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Indexed: 06/09/2023]
Abstract
A search for charge-parity (CP) violation in Cabibbo-suppressed D_{s}^{+}→K_{S}^{0}π^{+}, D^{+}→K_{S}^{0}K^{+}, and D^{+}→ϕπ^{+} decays is reported using proton-proton collision data, corresponding to an integrated luminosity of 3.8 fb^{-1}, collected at a center-of-mass energy of 13 TeV with the LHCb detector. High-yield samples of kinematically and topologically similar Cabibbo-favored D_{(s)}^{+} decays are analyzed to subtract nuisance asymmetries due to production and detection effects, including those induced by CP violation in the neutral kaon system. The results areA_{CP}(D_{s}^{+}→K_{S}^{0}π^{+})=(1.3±1.9±0.5)×10^{-3},A_{CP}(D^{+}→K_{S}^{0}K^{+})=(-0.09±0.65±0.48)×10^{-3},A_{CP}(D^{+}→ϕπ^{+})=(0.05±0.42±0.29)×10^{-3},where the first uncertainties are statistical and the second systematic. They are the most precise measurements of these quantities to date, and are consistent with CP symmetry. A combination with previous LHCb measurements, based on data collected at 7 and 8 TeV, is also reported.
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Observation of B_{(s)}^{0}→J/ψpp[over ¯] Decays and Precision Measurements of the B_{(s)}^{0} Masses. PHYSICAL REVIEW LETTERS 2019; 122:191804. [PMID: 31144973 DOI: 10.1103/physrevlett.122.191804] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 03/26/2019] [Indexed: 06/09/2023]
Abstract
The first observation of the decays B_{(s)}^{0}→J/ψpp[over ¯] is reported, using proton-proton collision data corresponding to an integrated luminosity of 5.2 fb^{-1}, collected with the LHCb detector. These decays are suppressed due to limited available phase space, as well as due to Okubo-Zweig-Iizuka or Cabibbo suppression. The measured branching fractions are B(B^{0}→J/ψpp[over ¯])=[4.51±0.40(stat)±0.44(syst)]×10^{-7}, B(B_{s}^{0}→J/ψpp[over ¯])=[3.58±0.19(stat)±0.39(syst)]×10^{-6}. For the B_{s}^{0} meson, the result is much higher than the expected value of O(10^{-9}). The small available phase space in these decays also allows for the most precise single measurement of both the B^{0} mass as 5279.74±0.30(stat)±0.10(syst) MeV and the B_{s}^{0} mass as 5366.85±0.19(stat)±0.13(syst) MeV.
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36
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Search for Lepton-Universality Violation in B^{+}→K^{+}ℓ^{+}ℓ^{-} Decays. PHYSICAL REVIEW LETTERS 2019; 122:191801. [PMID: 31144932 DOI: 10.1103/physrevlett.122.191801] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Indexed: 06/09/2023]
Abstract
A measurement of the ratio of branching fractions of the decays B^{+}→K^{+}μ^{+}μ^{-} and B^{+}→K^{+}e^{+}e^{-} is presented. The proton-proton collision data used correspond to an integrated luminosity of 5.0 fb^{-1} recorded with the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV. For the dilepton mass-squared range 1.1<q^{2}<6.0 GeV^{2}/c^{4} the ratio of branching fractions is measured to be R_{K}=0.846_{-0.054}^{+0.060}_{-0.014}^{+0.016}, where the first uncertainty is statistical and the second systematic. This is the most precise measurement of R_{K} to date and is compatible with the standard model at the level of 2.5 standard deviations.
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Model-Independent Observation of Exotic Contributions to B^{0}→J/ψK^{+}π^{-} Decays. PHYSICAL REVIEW LETTERS 2019; 122:152002. [PMID: 31050511 DOI: 10.1103/physrevlett.122.152002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Indexed: 06/09/2023]
Abstract
An angular analysis of B^{0}→J/ψK^{+}π^{-} decays is performed, using proton-proton collision data corresponding to an integrated luminosity of 3 fb^{-1} collected with the LHCb detector. The m(K^{+}π^{-}) spectrum is divided into fine bins. In each m(K^{+}π^{-}) bin, the hypothesis that the three-dimensional angular distribution can be described by structures induced only by K^{*} resonances is examined, making minimal assumptions about the K^{+}π^{-} system. The data reject the K^{*}-only hypothesis with a large significance, implying the observation of exotic contributions in a model-independent fashion. Inspection of the m(J/ψπ^{-}) vs m(K^{+}π^{-}) plane suggests structures near m(J/ψπ^{-})=4200 and 4600 MeV.
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First Measurement of Charm Production in its Fixed-Target Configuration at the LHC. PHYSICAL REVIEW LETTERS 2019; 122:132002. [PMID: 31012627 DOI: 10.1103/physrevlett.122.132002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 02/01/2019] [Indexed: 06/09/2023]
Abstract
The first measurement of heavy-flavor production by the LHCb experiment in its fixed-target mode is presented. The production of J/ψ and D^{0} mesons is studied with beams of protons of different energies colliding with gaseous targets of helium and argon with nucleon-nucleon center-of-mass energies of sqrt[s_{NN}]=86.6 and 110.4 GeV, respectively. The J/ψ and D^{0} production cross sections in pHe collisions in the rapidity range [2, 4.6] are found to be σ_{J/ψ}=652±33(stat)±42(syst) nb/nucleon and σ_{D^{0}}=80.8±2.4(stat)±6.3(syst) μb/nucleon, where the first uncertainty is statistical and the second is systematic. No evidence for a substantial intrinsic charm content of the nucleon is observed in the large Bjorken-x region.
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Measurement of the Charm-Mixing Parameter y_{CP}. PHYSICAL REVIEW LETTERS 2019; 122:011802. [PMID: 31012660 DOI: 10.1103/physrevlett.122.011802] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Indexed: 06/09/2023]
Abstract
A measurement of the charm-mixing parameter y_{CP} using D^{0}→K^{+}K^{-}, D^{0}→π^{+}π^{-}, and D^{0}→K^{-}π^{+} decays is reported. The D^{0} mesons are required to originate from semimuonic decays of B^{-} and B[over ¯]^{0} mesons. These decays are partially reconstructed in a data set of proton-proton collisions at center-of-mass energies of 7 and 8 TeV collected with the LHCb experiment and corresponding to an integrated luminosity of 3 fb^{-1}. The y_{CP} parameter is measured to be (0.57±0.13(stat)±0.09(syst))%, in agreement with, and as precise as, the current world-average value.
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Observation of Two Resonances in the Λ_{b}^{0}π^{±} Systems and Precise Measurement of Σ_{b}^{±} and Σ_{b}^{*±} Properties. PHYSICAL REVIEW LETTERS 2019; 122:012001. [PMID: 31012676 DOI: 10.1103/physrevlett.122.012001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Indexed: 06/09/2023]
Abstract
The first observation of two structures consistent with resonances in the final states Λ_{b}^{0}π^{-} and Λ_{b}^{0}π^{+} is reported using samples of pp collision data collected by the LHCb experiment at sqrt[s]=7 and 8 TeV, corresponding to an integrated luminosity of 3 fb^{-1}. The ground states Σ_{b}^{±} and Σ_{b}^{*±} are also confirmed and their masses and widths are precisely measured.
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Vitamin D deficiency influences fatty acid metabolism. Prostaglandins Leukot Essent Fatty Acids 2019; 140:57-63. [PMID: 30553405 DOI: 10.1016/j.plefa.2018.11.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 11/28/2018] [Accepted: 11/28/2018] [Indexed: 12/20/2022]
Abstract
Reports indicate that maternal vitamin D deficiency may be associated with increased inflammation. Long chain polyunsaturated fatty acids (LCPUFAs); omega-3 and omega-6 fatty acids are known to have anti-inflammatory and pro-inflammatory properties respectively. The present study examines the effect of vitamin D deficiency on fatty acid composition and metabolism in a rat model. Female Wistar rats were randomly divided into two groups (n = 8/group) as follows; control and vitamin D deficient (VDD). Diets (control: 1000 IU D3/kg diet; VDD: 0 IU D3/kg diet) were given from weaning and continued throughout pregnancy. Pregnant female rats were dissected on gestational day 20 to collect blood, liver and placenta. The VDD diet reduced maternal serum 25-hydroxyviatmin D3 levels (p < 0.001) as compared to control. Maternal vitamin D deficiency resulted in lower total weight gain and placental weight (p < 0.05 for both) during pregnancy. Animals from VDD group demonstrated higher arachidonic acid (AA) levels in both the liver and plasma (p < 0.05 for both) as compared to control. Liver, plasma and placental monounsaturated fatty acid levels (MUFA) were lower (p < 0.01 for all) while plasma total saturated fatty acids (SFA) (p = 0.05) were higher in the VDD group. Animals from the VDD group demonstrated lower ∆9-desaturase activity index (p < 0.01 for all) in the liver, plasma and placenta. The plasma ∆5-desaturase activity index (p < 0.05) was higher although no change was observed in the ∆6-desaturase activity index. However, the mRNA levels of liver ∆6-desaturase was lower (p < 0.05) in the VDD group. Our findings indicate that maternal vitamin D deficiency influences fatty acid desaturase activity and expression and therefore alters maternal fatty acid metabolism.
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Evidence for an η c ( 1 S ) π - resonance in B 0 → η c ( 1 S ) K + π - decays. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:1019. [PMID: 30872960 PMCID: PMC6383874 DOI: 10.1140/epjc/s10052-018-6447-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 11/13/2018] [Indexed: 06/09/2023]
Abstract
A Dalitz plot analysis of B 0 → η c ( 1 S ) K + π - decays is performed using data samples of pp collisions collected with the LHCb detector at centre-of-mass energies of s = 7 , 8 and 13 Te V , corresponding to a total integrated luminosity of 4.7 fb - 1 . A satisfactory description of the data is obtained when including a contribution representing an exotic η c ( 1 S ) π - resonant state. The significance of this exotic resonance is more than three standard deviations, while its mass and width are 4096 ± 20 - 22 + 18 Me V and 152 ± 58 - 35 + 60 Me V , respectively. The spin-parity assignments J P = 0 + and J P = 1 - are both consistent with the data. In addition, the first measurement of the B 0 → η c ( 1 S ) K + π - branching fraction is performed and gives B ( B 0 → η c ( 1 S ) K + π - ) = ( 5.73 ± 0.24 ± 0.13 ± 0.66 ) × 10 - 4 , where the first uncertainty is statistical, the second systematic, and the third is due to limited knowledge of external branching fractions.
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Search for lepton-flavour-violating decays of Higgs-like bosons. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018; 78:1008. [PMID: 30872958 PMCID: PMC6383911 DOI: 10.1140/epjc/s10052-018-6386-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 10/29/2018] [Indexed: 06/09/2023]
Abstract
A search is presented for a Higgs-like boson with mass in the range 45 to 195 GeV / c 2 decaying into a muon and a tau lepton. The dataset consists of proton-proton interactions at a centre-of-mass energy of 8 TeV , collected by the LHCb experiment, corresponding to an integrated luminosity of 2 fb - 1 . The tau leptons are reconstructed in both leptonic and hadronic decay channels. An upper limit on the production cross-section multiplied by the branching fraction at 95% confidence level is set and ranges from 22 pb for a boson mass of 45 GeV / c 2 to 4 pb for a mass of 195 GeV / c 2 .
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Measurement of Antiproton Production in p-He Collisions at sqrt[s_{NN}]=110 GeV. PHYSICAL REVIEW LETTERS 2018; 121:222001. [PMID: 30547629 DOI: 10.1103/physrevlett.121.222001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 10/09/2018] [Indexed: 06/09/2023]
Abstract
The cross section for prompt antiproton production in collisions of protons with an energy of 6.5 TeV incident on helium nuclei at rest is measured with the LHCb experiment from a data set corresponding to an integrated luminosity of 0.5 nb^{-1}. The target is provided by injecting helium gas into the LHC beam line at the LHCb interaction point. The reported results, covering antiproton momenta between 12 and 110 GeV/c, represent the first direct determination of the antiproton production cross section in p-He collisions, and impact the interpretation of recent results on antiproton cosmic rays from space-borne experiments.
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First Observation of the Doubly Charmed Baryon Decay Ξ_{cc}^{++}→Ξ_{c}^{+}π^{+}. PHYSICAL REVIEW LETTERS 2018; 121:162002. [PMID: 30387661 DOI: 10.1103/physrevlett.121.162002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 08/01/2018] [Indexed: 06/08/2023]
Abstract
The doubly charmed baryon decay Ξ_{cc}^{++}→Ξ_{c}^{+}π^{+} is observed for the first time, with a statistical significance of 5.9σ, confirming a recent observation of the baryon in the Λ_{c}^{+}K^{-}π^{+}π^{+} final state. The data sample used corresponds to an integrated luminosity of 1.7 fb^{-1}, collected by the LHCb experiment in pp collisions at a center-of-mass energy of 13 TeV. The Ξ_{cc}^{++} mass is measured to be 3620.6±1.5(stat)±0.4(syst)±0.3(Ξ_{c}^{+}) MeV/c^{2} and is consistent with the previous result. The ratio of branching fractions between the decay modes is measured to be [B(Ξ_{cc}^{++}→Ξ_{c}^{+}π^{+})×B(Ξ_{c}^{+}→pK^{-}π^{+})]/[B(Ξ_{cc}^{++}→Λ_{c}^{+}K^{-}π^{+}π^{+})×B(Λ_{c}^{+}→pK^{-}π^{+})]=0.035±0.009(stat)±0.003(syst).
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Measurement of Angular and CP Asymmetries in D^{0}→π^{+}π^{-}μ^{+}μ^{-} and D^{0}→K^{+}K^{-}μ^{+}μ^{-} Decays. PHYSICAL REVIEW LETTERS 2018; 121:091801. [PMID: 30230851 DOI: 10.1103/physrevlett.121.091801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Indexed: 06/08/2023]
Abstract
The first measurements of the forward-backward asymmetry of the dimuon pair (A_{FB}), the triple-product asymmetry (A_{2ϕ}), and the charge-parity-conjugation asymmetry (A_{CP}), in D^{0}→π^{+}π^{-}μ^{+}μ^{-} and D^{0}→K^{+}K^{-}μ^{+}μ^{-} decays are reported. They are performed using data from proton-proton collisions collected with the LHCb experiment from 2011 to 2016, corresponding to a total integrated luminosity of 5 fb^{-1}. The asymmetries are measured to be A_{FB}(D^{0}→π^{+}π^{-}μ^{+}μ^{-})=(3.3±3.7±0.6)%, A_{2ϕ}(D^{0}→π^{+}π^{-}μ^{+}μ^{-})=(-0.6±3.7±0.6)%, A_{CP}(D^{0}→π^{+}π^{-}μ^{+}μ^{-})=(4.9±3.8±0.7)%, A_{FB}(D^{0}→K^{+}K^{-}μ^{+}μ^{-})=(0±11±2)%, A_{2ϕ}(D^{0}→K^{+}K^{-}μ^{+}μ^{-})=(9±11±1)%, A_{CP}(D^{0}→K^{+}K^{-}μ^{+}μ^{-})=(0±11±2)%, where the first uncertainty is statistical and the second systematic. The asymmetries are also measured as a function of the dimuon invariant mass. The results are consistent with the standard model predictions.
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Measurement of the Ω_{c}^{0} Baryon Lifetime. PHYSICAL REVIEW LETTERS 2018; 121:092003. [PMID: 30230895 DOI: 10.1103/physrevlett.121.092003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 07/31/2018] [Indexed: 06/08/2023]
Abstract
We report a measurement of the lifetime of the Ω_{c}^{0} baryon using proton-proton collision data at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3.0 fb^{-1} collected by the LHCb experiment. The sample consists of about 1000 Ω_{b}^{-}→Ω_{c}^{0}μ^{-}ν[over ¯]_{μ}X signal decays, where the Ω_{c}^{0} baryon is detected in the pK^{-}K^{-}π^{+} final state and X represents possible additional undetected particles in the decay. The Ω_{c}^{0} lifetime is measured to be τ_{Ω_{c}^{0}}=268±24±10±2 fs, where the uncertainties are statistical, systematic, and from the uncertainty in the D^{+} lifetime, respectively. This value is nearly four times larger than, and inconsistent with, the current world-average value.
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Abstract
From samples of pp collision data collected by the LHCb experiment at sqrt[s]=7, 8 and 13 TeV, corresponding to integrated luminosities of 1.0, 2.0 and 1.5 fb^{-1}, respectively, a peak in both the Λ_{b}^{0}K^{-} and Ξ_{b}^{0}π^{-} invariant mass spectra is observed. In the quark model, radially and orbitally excited Ξ_{b}^{-} resonances with quark content bds are expected. Referring to this peak as Ξ_{b}(6227)^{-}, the mass and natural width are measured to be m_{Ξ_{b}(6227)^{-}}=6226.9±2.0±0.3±0.2 MeV/c^{2} and Γ_{Ξ_{b}(6227)^{-}}=18.1±5.4±1.8 MeV/c^{2}, where the first uncertainty is statistical, the second is systematic, and the third, on m_{Ξ_{b}(6227)^{-}}, is due to the knowledge of the Λ_{b}^{0} baryon mass. Relative production rates of the Ξ_{b}(6227)^{-}→Λ_{b}^{0}K^{-} and Ξ_{b}(6227)^{-}→Ξ_{b}^{0}π^{-} decays are also reported.
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Measurement of the Lifetime of the Doubly Charmed Baryon Ξ_{cc}^{++}. PHYSICAL REVIEW LETTERS 2018; 121:052002. [PMID: 30118314 DOI: 10.1103/physrevlett.121.052002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 06/24/2018] [Indexed: 06/08/2023]
Abstract
The first measurement of the lifetime of the doubly charmed baryon Ξ_{cc}^{++} is presented, with the signal reconstructed in the final state Λ_{c}^{+}K^{-}π^{+}π^{+}. The data sample used corresponds to an integrated luminosity of 1.7 fb^{-1}, collected by the LHCb experiment in proton-proton collisions at a center-of-mass energy of 13 TeV. The Ξ_{cc}^{++} lifetime is measured to be 0.256_{-0.022}^{+0.024}(stat)±0.014(syst) ps.
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Amplitude Analysis of the Decay B[over ¯]^{0}→K_{S}^{0}π^{+}π^{-} and First Observation of the CP Asymmetry in B[over ¯]^{0}→K^{*}(892)^{-}π^{+}. PHYSICAL REVIEW LETTERS 2018; 120:261801. [PMID: 30004725 DOI: 10.1103/physrevlett.120.261801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 03/15/2018] [Indexed: 06/08/2023]
Abstract
The time-integrated untagged Dalitz plot of the three-body hadronic charmless decay B[over ¯]^{0}→K_{S}^{0}π^{+}π^{-} is studied using a pp collision data sample recorded with the LHCb detector, corresponding to an integrated luminosity of 3.0 fb^{-1}. The decay amplitude is described with an isobar model. Relative contributions of the isobar amplitudes to the B[over ¯]^{0}→K_{S}^{0}π^{+}π^{-} decay branching fraction and CP asymmetries of the flavor-specific amplitudes are measured. The CP asymmetry between the conjugate B[over ¯]^{0}→K^{*}(892)^{-}π^{+} and B^{0}→K^{*}(892)^{+}π^{-} decay rates is determined to be -0.308±0.062.
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