| 1. |
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| 2. |
- Bauer, Patrik Maximilian, et al.
(författare)
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Inflamed In Vitro Retina : Cytotoxic Neuroinflammation and Galectin-3 Expression
- 2016
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 11:9
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Tidskriftsartikel (refereegranskat)abstract
- Background Disease progression in retinal neurodegeneration is strongly correlated to immune cell activation, which may have either a neuroprotective or neurotoxic effect. Increased knowledge about the immune response profile and retinal neurodegeneration may lead to candidate targets for treatments. Therefore, we have used the explanted retina as a model to explore the immune response and expression of the immune modulator galectin-3 (Gal-3), induced by the cultivation per se and after additional immune stimulation with lipopolysaccharide (LPS), and how this correlates with retinal neurotoxicity. Methods Post-natal mouse retinas were cultured in a defined medium. One group was stimulated with LPS (100 ng/ml, 24 h). Retinal architecture, apoptotic cell death, and micro- and macroglial activity were studied at the time of cultivation (0 days in vitro (DIV)) and at 3, 4 and 7 DIV using morphological staining, biochemical- and immunohistochemical techniques. Results Our results show that sustained activation of macro- and microglia, characterized by no detectable cytokine release and limited expression of Gal-3, is not furtherinducing apoptosis additional to the axotomy-induced apoptosis in innermost nuclear layer. An elevated immune response was detected after LPS stimulation, as demonstrated primarily by release of immune mediators (i.e. interleukin 2 (IL-2), IL-6, KC/GRO (also known as CLCX1) and tumour necrosis factor-α (TNF-α)), increased numbers of microglia displaying morphologies of late activation stages as well as Gal-3 expression. This was accompanied with increased apoptosis in the two additional nuclear layers, and damage to retinal gross architecture. Conclusion We demonstrate that an immune response characterized by sustained and increased release of cytokines, along with an increase in Gal-3 expression, is accompanied by significant increased neurotoxicity in the explanted retina. Further investigations using the current setting may lead to increased understanding on the mechanisms involved in neuronal loss in retinal neurodegenerations. © 2016 Bauer et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
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| 3. |
- Ekstam, Börje, et al.
(författare)
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Predicting risk habitats for the transmission of the small liver fluke, Dicrocoelium dendriticum to grazing ruminants.
- 2011
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Ingår i: Geospatial Health. - Naples, Italy : Global Network for Geospatial Health. - 1827-1987 .- 1970-7096. ; 6:1, s. 125-131
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Tidskriftsartikel (refereegranskat)abstract
- A multiple regression model was used to analyse if the structure of vegetation and soil patches in grazed units (pastures) can be used as explanatory variables to predict the prevalence of Dicrocoelium dendriticum, a common parasite of cattle and sheep, in grazing cattle stocks on the Baltic island of Öland in southern Sweden.The scale dependency was evaluated by comparing three levels of spatial resolution of patches. Prevalence data were obtained from slaughtered animals.Our models predict that the prevalence of D. dendriticum increases in grazed areas with woody vegetation, whereas moist and wet areas decrease parasite prevalence. The predictive power of the statistical models increased with increasing level of patch resolution. Approximately 42% of the variation in parasite prevalence (angular transformation) was explained by the areal proportion of vegetation types (4th-root-transformed).Based on the results obtained, we believe that our model strategy provides a rational and systematic tool to identify habitats that carry risk for D. dendriticum infection of ruminants, and that it can be applied to other parasites with similar life cycles such as Fasciola hepatica.
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| 4. |
- Holmberg, Ulrik, et al.
(författare)
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Frågedriven undervisning för att organisera normativa kunskapspraktiker i SO-ämnena
- 2022
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Ingår i: Nordidactica. - : Karlstads universitet. - 2000-9879. ; :4, s. 124-153
-
Tidskriftsartikel (refereegranskat)abstract
- This is a mainly conceptual and argumentative article which presents a model for enquiry-based teaching (Swedish acronym FDU - frågedrivenundervisning). The purpose is to suggest and discuss how enquiry-based teaching can contribute to organising qualified subject teaching in history, religious education and social studies. This is dealt with through two sections. The first section presents a structure for enquiry-based teaching through tested teaching designs in the three subjects, and the second section discusses certain qualities of enquiry-based teaching that we argue should be maintained. Based on actual teaching and teachers' experiences of designing enquiry-based teaching, the article positions FDU as a subject didactic teaching model. Hordern's (2022) framework for normative knowledge practices forms the theoretical starting point for discussing FDU as a subject didactic model that can help teachers in designing, planning, implementing and evaluating qualified subject teaching.The article argues that FDU can be regarded as a normative knowledge practice that is characterised by the qualities of being enquiry-based, prospective, consistent, assessment-oriented, and continuous.
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| 5. |
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| 6. |
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| 7. |
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| 8. |
- Johansson, Maria, et al.
(författare)
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Enquiries in history : Experiences from a professional development seminar series
- 2021
-
Ingår i: Professional development 2 (papers).
-
Konferensbidrag (refereegranskat)abstract
- The aim of the research project (financed by Swedish Institute for Educational Research) is to develop the enquiry method as an educational approach for teachers to develop students’ critical abilities. Enquiry is a student-active method with the potential to enhance students’ learning under the guidance and instruction from proficient teachers. Therefore, it requires high demands on teachers' academic and subject didactical knowledge. The project is a researcher-teacher collaborative study where around thirty teachers from three school subjects (history, religious education and social studies) have designed and tested enquiries. During the three-year project (2020-2023) three research questions will be addressed: 1) how the method works as a knowledge-generating approach for students in a Swedish school context, 2) what characterizes teachers’ competence to construct and teach enquiries, and 3) how this competence can be advanced within the framework of a professional learning community.We present the theoretical context for a professional development seminar series called Doing Enquiry, and empirical samples and experiences from its implementation including enquiries designed and performed by the history teachers. Starting from the IDM-framework (Swan, Lee, & Grant, 2018), this seminar series focuses on the collaborative construction of enquiries. A hypothesis for the seminar series was that it would be crucial to provide an opportunity to take the role of the teacher as well as being positioned as a pupil in the construction phase of an enquiry. So far, preliminary results will reflect on the second and third question. The results indicate that some elements in history teachers’ competences, that professional development can enhance, are particularly important, e.g., a systematic approach to the planning, implementation and teaching of an enquiry; using a shared subject didactic knowledge within a professional community; and, deep academic knowledge.
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| 9. |
- Johansson, Magdalena, 1984-, et al.
(författare)
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Physical activity and risk of first-time venous thromboembolism
- 2019
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Ingår i: European Journal of Preventive Cardiology. - : Sage Publications. - 2047-4873 .- 2047-4881. ; 26:11, s. 1181-1187
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Physical activity may have a protective effect against venous thromboembolism (VTE). The aim of this study was to investigate the association between leisure time physical activity, occupational physical activity, and the risk of VTE in men and women separately.Methods: The population-based, prospective Venous thromboEmbolism In Northern Sweden (VEINS) cohort study included 108,025 participants of health examinations between 1985 and 2014. Physical activity data were collected by questionnaire. Participants were followed from health examination to first-time VTE event, death, emigration or the end of the study. All VTE events were validated by reviewing medical records and radiology reports.Results: During 1,496,669 person-years, 2054 participants experienced VTE. Women who performed leisure time physical activity at least once a week had a lower risk of first-time VTE (hazard ratio (HR) 0.83; 95% confidence interval (CI) 0.71–0.98 after adjustments) compared with women with less or no physical activity. Furthermore, women with high occupational physical activity also had a lower risk of VTE (HR 0.85; 95% CI 0.74–0.98). In men, there was no consistent association between either measure of physical activity and the risk of VTE.Conclusion: We found an association between increased physical activity and a lower risk of first-time VTE in women.
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| 10. |
- Maria, Johansson, et al.
(författare)
-
Historiebruk
- 2021
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Ingår i: Puls SO 5. - Stockholm : Natur och kultur. - 9789127459854 ; , s. 24-27
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Bokkapitel (populärvet., debatt m.m.)abstract
- Ett av målen i kursplanen för historia är att förstå hur historia används, och har använts, för olika syften och behov och av olika individer och grupper. Vanligen kallas detta historiebruk. Här följer en introduktion till historiebruk och förslag på hur man kan arbeta med det i undervisningen.
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| 11. |
- Rasmussen, Eva Rye, et al.
(författare)
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Genome-wide association study of angioedema induced by angiotensin-converting enzyme inhibitor and angiotensin receptor blocker treatment.
- 2020
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Ingår i: The Pharmacogenomics Journal. - : Springer Science and Business Media LLC. - 1470-269X .- 1473-1150. ; 20:6, s. 770-783
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Tidskriftsartikel (refereegranskat)abstract
- Angioedema in the mouth or upper airways is a feared adverse reaction to angiotensin-converting enzyme inhibitor (ACEi) and angiotensin receptor blocker (ARB) treatment, which is used for hypertension, heart failure and diabetes complications. This candidate gene and genome-wide association study aimed to identify genetic variants predisposing to angioedema induced by these drugs. The discovery cohort consisted of 173 cases and 4890 controls recruited in Sweden. In the candidate gene analysis, ETV6, BDKRB2, MME, and PRKCQ were nominally associated with angioedema (p < 0.05), but did not pass Bonferroni correction for multiple testing (p < 2.89 × 10-5). In the genome-wide analysis, intronic variants in the calcium-activated potassium channel subunit alpha-1 (KCNMA1) gene on chromosome 10 were significantly associated with angioedema (p < 5 × 10-8). Whilst the top KCNMA1 hit was not significant in the replication cohort (413 cases and 599 ACEi-exposed controls from the US and Northern Europe), a meta-analysis of the replication and discovery cohorts (in total 586 cases and 1944 ACEi-exposed controls) revealed that each variant allele increased the odds of experiencing angioedema 1.62 times (95% confidence interval 1.05-2.50, p = 0.030). Associated KCNMA1 variants are not known to be functional, but are in linkage disequilibrium with variants in transcription factor binding sites active in relevant tissues. In summary, our data suggest that common variation in KCNMA1 is associated with risk of angioedema induced by ACEi or ARB treatment. Future whole exome or genome sequencing studies will show whether rare variants in KCNMA1 or other genes contribute to the risk of ACEi- and ARB-induced angioedema.
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| 12. |
- Söderstjerna, Erika, et al.
(författare)
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Silver and Gold Nanoparticles Exposure to In Vitro Cultured Retina : Studies on Nanoparticle Internalization, Apoptosis, Oxidative Stress, Glial- and Microglial Activity
- 2014
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:8
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Tidskriftsartikel (refereegranskat)abstract
- The complex network of neuronal cells in the retina makes it a potential target of neuronal toxicity - a risk factor for visual loss. With growing use of nanoparticles (NPs) in commercial and medical applications, including ophthalmology, there is a need for reliable models for early prediction of NP toxicity in the eye and retina. Metal NPs, such as gold and silver, gain much of attention in the ophthalmology community due to their potential to cross the barriers of the eye. Here, NP uptake and signs of toxicity were investigated after exposure to 20 and 80 nm Ag- and AuNPs, using an in vitro tissue culture model of the mouse retina. The model offers long-term preservation of retinal cell types, numbers and morphology and is a controlled system for delivery of NPs, using serum-free defined culture medium. AgNO3-treatment was used as control for toxicity caused by silver ions. These end-points were studied; gross morphological organization, glial activity, microglial activity, level of apoptosis and oxidative stress, which are all well described as signs of insult to neural tissue. TEM analysis demonstrated cellular- and nuclear uptake of all NP types in all neuronal layers of the retina. Htx-eosin staining showed morphological disruption of the normal complex layered retinal structure, vacuole formation and pyknotic cells after exposure to all Ag- and AuNPs. Significantly higher numbers of apoptotic cells as well as an increased number of oxidative stressed cells demonstrated NP-related neuronal toxicity. NPs also caused increased glial staining and microglial cell activation, typical hallmarks of neural tissue insult. This study demonstrates that low concentrations of 20 and 80 nm sized Ag- and AuNPs have adverse effects on the retina, using an organotypic retina culture model. Our results motivate careful assessment of candidate NP, metallic or-non-metallic, to be used in neural systems for therapeutic approaches.
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| 13. |
- Veje, Malin, et al.
(författare)
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Diagnosing tick-borne encephalitis: a re-evaluation of notified cases
- 2018
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Ingår i: European Journal of Clinical Microbiology and Infectious Diseases. - : Springer Science and Business Media LLC. - 0934-9723 .- 1435-4373. ; 37:2, s. 339-344
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Tidskriftsartikel (refereegranskat)abstract
- We set out to investigate the serological response of TBE virus (TBEV)-specific IgM and IgG antibodies in stored serum and cerebrospinal fluid (CSF) in notified TBE patients, in order to confirm or reject the diagnosis. We applied the ELISA methods used in clinical practice, Enzygnost and Immunozym, and assessed RT-PCR as a diagnostic tool. A total of 173 TBE cases were notified to the Public Health Agency. Samples from 129 patients were eligible for the study. Stored serum samples were found for 111 patients and CSF samples for 88 patients. All serum samples were analyzed with both Enzygnost and Immunozym, as well as an additional 140 control samples. CSF samples, including samples from ten controls, were analyzed with Immunozym. RT-PCR for TBEV was performed on 126 serum, two whole blood, 96 CSF, two feces and four nasopharynx samples. Only two of 111 notified patients lacked detectable TBEV IgM in serum, from whom one sample was RT-PCR positive. According to the ECDC definition, 117/129 (90.7%) of the reported TBE cases were confirmed. Positive RT-PCR results were obtained in eight patients, one from whole blood and eight from serum samples. Four out of eight of the RT-PCR positive patients were TBEV-IgM positive and none had detectable TBEV-specific IgG. All of the tested CSF, feces and nasopharynx samples were RT-PCR-negative. TBEV-specific IgG was detected in 88.4% and IgM in 31.6% of the CSF samples. RT-PCR on serum samples and CSF IgG antibodies can be used as complementary methods in TBE diagnostics, not least early in the disease course.
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| 14. |
- Wagner, Annemarie, 1954, et al.
(författare)
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Carbon Dioxide Capture from Ambient Air Using Amine-Grafted Mesoporous Adsorbents
- 2013
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Ingår i: International Journal of Spectroscopy. - : Hindawi Limited. - 1687-9457 .- 1687-9449. ; 2013
-
Tidskriftsartikel (refereegranskat)abstract
- Anthropogenic emissions of carbon dioxide (CO2) have been identified as a major contributor to climate change. An attractive approach to tackle the increasing levels of CO2 in the atmosphere is direct extraction via absorption of CO2 from ambient air, to be subsequently desorbed and processed under controlled conditions. The feasibility of this approach depends on the sorbent material that should combine a long lifetime with nontoxicity, high selectivity for CO2, and favorable thermodynamic cycling properties. Adsorbents based on pore-expanded mesoporous silica grafted with amines have previously been found to combine high CO2 adsorption capacity at low partial pressures with operational stability under highly defined laboratory conditions. Here we examine the real potential and functionality of these materials by using more realistic conditions using both pure CO2, synthetic air, and, most importantly, ambient air. Through a combination of thermogravimetric analysis and Fourier transform infrared (TGA-FTIR) spectroscopy we address the primary functionality and by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy the observed degradation of the material on a molecular level.
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| 15. |
- Weishaupt, Holger, et al.
(författare)
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Batch-normalization of cerebellar and medulloblastoma gene expression datasets utilizing empirically defined negative control genes
- 2019
-
Ingår i: Bioinformatics. - : Oxford University Press. - 1367-4803 .- 1367-4811. ; 35:18, s. 3357-3364
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Tidskriftsartikel (refereegranskat)abstract
- Motivation: Medulloblastoma (MB) is a brain cancer predominantly arising in children. Roughly 70% of patients are cured today, but survivors often suffer from severe sequelae. MB has been extensively studied by molecular profiling, but often in small and scattered cohorts. To improve cure rates and reduce treatment side effects, accurate integration of such data to increase analytical power will be important, if not essential.Results: We have integrated 23 transcription datasets, spanning 1350 MB and 291 normal brain samples. To remove batch effects, we combined the Removal of Unwanted Variation (RUV) method with a novel pipeline for determining empirical negative control genes and a panel of metrics to evaluate normalization performance. The documented approach enabled the removal of a majority of batch effects, producing a large-scale, integrative dataset of MB and cerebellar expression data. The proposed strategy will be broadly applicable for accurate integration of data and incorporation of normal reference samples for studies of various diseases. We hope that the integrated dataset will improve current research in the field of MB by allowing more large-scale gene expression analyses.
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| 16. |
- Ablikim, M., et al.
(författare)
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Absolute measurements of branching fractions of Cabibbo-suppressed hadronic D0(+) decays involving multiple pions
- 2022
-
Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 106:9
-
Tidskriftsartikel (refereegranskat)abstract
- By analyzing e(+)e(-) annihilation data with an integrated luminosity of 2.93 fb(-1) collected at the center-of-mass energy root s = 3.773 GeV with the BESIII detector, we present the first absolute measurements of the branching fractions of twenty Cabibbo-suppressed hadronic D0(+) decays involving multiple pions. The highest four branching fractions obtained are B(D-0 -> pi(+)pi(-)pi(0)) = (1.343 +/- 0.013(stat) +/- 0.016(syst))%, B(D-0 -> pi(+)pi(-)2 pi(0)) = (1.002 +/- 0.019(stat )+/- 0.024(syst))%, B(D-0 -> 2 pi(+)pi(-)pi(0))=(1.165 +/- 0.021(stat) +/- 0.021(sy)(st))%, and B(D+ -> 2 pi(+)pi(-)pi(0)). (1.074 +/- 0.040(stat) 0.030(syst))%. The CP asymmetries for the six decays with highest signal yields are also determined and found to be compatible with zero.
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| 17. |
- Ablikim, M., et al.
(författare)
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Amplitude analysis and branching fraction measurement of D-s(+)-> K- K+ pi(+) pi(0)
- 2021
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Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 104:3
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Tidskriftsartikel (refereegranskat)abstract
- The first amplitude analysis of the decay D-s(+)-> K- K+ pi(+) pi(0) is presented using the data samples, corresponding to an integrated luminosity of 6.32 fb(-1), collected with the BESIII detector at e(+)e(-) center-of-mass energies between 4.178 and 4.226 GeV. More than 3000 events selected with a purity of 97.5% are used to perform the amplitude analysis, and nine components are found necessary to describe the data.
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| 18. |
- Ablikim, M., et al.
(författare)
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Amplitude analysis and branching-fraction measurement of D-s(+) -> K-S(0)pi(+)pi(0)
- 2021
-
Ingår i: Journal of High Energy Physics (JHEP). - : Springer Nature. - 1126-6708 .- 1029-8479. ; :6
-
Tidskriftsartikel (refereegranskat)abstract
- By using 6.32 fb(-1) of data collected with the BESIII detector at center-of-mass energies between 4.178 and 4.226 GeV, we perform an amplitude analysis of the decay D-s(+) -> K-S(0) pi(+)pi(0) and determine the relative fractions and phase differences of different intermediate processes, which include K-S(0) rho(770)(+), K-S(0)rho(1450)(+), K*(892)(0) pi(+), K* (892)(+) pi(0), and K* (1410)(0) pi(+). With the detection efficiency based on the amplitude analysis results, the absolute branching fraction is measured to be B(D-s(+) -> K-S(0) pi(+) pi(0)) = (5.43 +/- 0.30(stat) +/- 0.15(syst)) x 10(-3).
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| 19. |
- Ablikim, M., et al.
(författare)
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Amplitude analysis and branching-fraction measurement of D+s → K0SK−π+π
- 2021
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Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 103:9
-
Tidskriftsartikel (refereegranskat)abstract
- Using 6.32 fb−1 of e+e− collision data collected by the BESIII detector at the center-of-mass energies between 4.178 and 4.226 GeV, an amplitude analysis of the D+s → K0SK−π+π+ decays is performed for the first time to determine the intermediate-resonant contributions. The dominant component is the D+s → K∗(892)+¯K∗(892)0 decay with a fraction of (40.6±2.9stat±4.9sys)%. Our results of the amplitude analysis are used to obtain a more precise measurement of the branching fraction of the D+s → K0SK−π+π+ decay, which is determined to be (1.46±0.05stat±0.05sys)%.
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| 20. |
- Ablikim, M., et al.
(författare)
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Amplitude analysis and branching fraction measurement of D+s → K−K+π+π+π−
- 2022
-
Ingår i: Journal of High Energy Physics (JHEP). - : Springer Nature. - 1126-6708 .- 1029-8479. ; :7
-
Tidskriftsartikel (refereegranskat)abstract
- Using e(+)e(-) annihilation data corresponding to a total integrated luminosity of 6.32 fb(-1) collected at the center-of-mass energies between 4.178 and 4.226 GeV with the BE- SIII detector, we perform an amplitude analysis of the decay D-s(+) -> K-K+pi(+)pi(+)pi(-) and de-termine the relative fractions and phases of different intermediate processes. Absolute branch- ing fraction of D-s(+) -> K-K+pi(+)pi(+)pi(-) decay is measured to be (6.60 +/- 0.47(stat). +/- 0.38(syst).) x 10(-3). The dominant intermediate process is D-s(+) -> a(1) (1260)(+)phi,phi -> K- K+, a(1)(1260)(+) -> rho pi(+), rho -> pi(+)pi(-), with a branching fraction of (5.15 +/- 0.41(stat.) +/- 0.32(syst.)) x 10(-3).
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| 21. |
- Ablikim, M., et al.
(författare)
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Amplitude analysis and branching-fraction measurement of D+s → π+π0η′
- 2022
-
Ingår i: Journal of High Energy Physics (JHEP). - : Springer Nature. - 1126-6708 .- 1029-8479. ; :4
-
Tidskriftsartikel (refereegranskat)abstract
- Using data collected with the BESIII detector in e(+)e(-) collisions at center-of-mass energies between 4.178 and 4.226 GeV and corresponding to 6.32 fb(-1) of integrated luminosity, we report the amplitude analysis and branching-fraction measurement of the D-s(+) -> pi(+)pi(0)eta' decay. We find that the dominant intermediate process is D-s(+) -> rho(+)eta' and the significances of other resonant and nonresonant processes are all less than 3 sigma. The upper limits on the branching fractions of S-wave and P-wave nonresonant components are set to 0.10% and 0.74% at the 90% confidence level, respectively. In addition, the branching fraction of the D-s(+) -> pi(+)pi(0)eta' decay is measured to be (6.15 +/- 0.25(stat.) +/- 0.18(syst.))%, which receives significant contribution only from D-s(+) -> rho(+)eta' according to the amplitude analysis.
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| 22. |
- Ablikim, M., et al.
(författare)
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Amplitude analysis and branching fraction measurement of Ds+ → K+K-π
- 2021
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Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 104:1
-
Tidskriftsartikel (refereegranskat)abstract
- We report an amplitude analysis and branching fraction measurement of D-s(+) -> K+K-pi(+) decay using a data sample of 3.19 fb(-1) recorded with BESIII detector at a center-of-mass energy of 4.178 GeV. We perform a model-independent partial wave analysis in the low K+K- mass region to determine the K+K- S-wave line shape, followed by an amplitude analysis of our very pure high-statistics sample. With the detection efficiency based on the amplitude analysis results, the absolute branching fraction is measured to be B(D-s(+) -> K+K-pi(+)) = (5.47 +/- 0.08(stat) +/- 0.13(sys))%.
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| 23. |
- Ablikim, M., et al.
(författare)
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Amplitude analysis and branching fraction measurement of the decay D+ K0S → π+π0π0
- 2023
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Ingår i: Journal of High Energy Physics (JHEP). - : Springer. - 1126-6708 .- 1029-8479. ; :9
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Tidskriftsartikel (refereegranskat)abstract
- Using 2.93 fb−1 of e+e− collision data collected with the BESIII detector at the center-of-mass energy 3.773 GeV, we perform the first amplitude analysis of the decay D+ → π+π0π0 and determine the relative magnitudes and phases of different intermediate processes. The absolute branching fraction of D+ → π+π0π0 is measured to be (2.888 ± 0.058stat. ± 0.069syst.)%. The dominant intermediate processes are D+ → a1(1260)+(→ ρ+π0) and D+ → *0ρ+, with branching fractions of (8.66 ± 1.04stat. ± 1.39syst.) × 10−3 and (9.70 ± 0.81stat. ± 0.53syst.) × 10−3, respectively.
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| 24. |
- Ablikim, M., et al.
(författare)
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Amplitude analysis and branching fraction measurement of the decay D+s → K+π+π−
- 2022
-
Ingår i: Journal of High Energy Physics (JHEP). - : Springer. - 1126-6708 .- 1029-8479. ; :8
-
Tidskriftsartikel (refereegranskat)abstract
- Using 6.32 fb−1 of e+e− collision data collected at the center-of-mass energies between 4.178 and 4.226 GeV with the BESIII detector, we perform an amplitude analysis of the decay D+s → K+π+π− and determine the amplitudes of the various intermediate states. The absolute branching fraction of D+s → K+π+π− is measured to be (6.11 ± 0.18stat. ± 0.11syst.) × 10−3. The branching fractions of the dominant intermediate processes D+s → K+ρ0, ρ0 → π+π− and D+s → K*(892)0π+, K*(892)0 → K+π− are determined to be (1.96 ± 0.19stat. ± 0.23syst.) × 10−3 and (1.85 ± 0.12stat. ± 0.13syst.) × 10−3, respectively. The intermediate resonances f0(500), f0(980), and f0(1370) are observed for the first time in this channel.
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| 25. |
- Ablikim, M., et al.
(författare)
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Amplitude analysis and branching fraction measurement of the decay D+s → K+π+π−π0
- 2022
-
Ingår i: Journal of High Energy Physics (JHEP). - : Springer. - 1126-6708 .- 1029-8479. ; :9
-
Tidskriftsartikel (refereegranskat)abstract
- The singly Cabibbo-suppressed decay D+s → K+π+π−π0 is observed by using a data set corresponding to an integrated luminosity of 6.32 fb−1 recorded by the BESIII detector at the centre-of-mass energies between 4.178 and 4.226 GeV. The first amplitude analysis of D+s → K+π+π−π0 reveals the sub-structures in this decay and determines the fractions and relative phases of different intermediate processes. The dominant intermediate process is D+s → K*0ρ+, with a fit fraction of (40.5 ± 2.8stat. ± 1.5syst.)%. With the detection efficiency based on our amplitude analysis, the absolute branching fraction for D+s → K+π+π−π0 is measured to be (9.75 ± 0.54stat. ± 0.17syst.) × 10−3.
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| 26. |
- Ablikim, M., et al.
(författare)
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Amplitude analysis and branching fraction measurement of the decay D-s(+) -> pi(+)pi(0)pi(0)
- 2022
-
Ingår i: Journal of High Energy Physics (JHEP). - : Springer. - 1126-6708 .- 1029-8479. ; :1
-
Tidskriftsartikel (refereegranskat)abstract
- Using a data set corresponding to an integrated luminosity of 6.32fb(-1) recorded by the BESIII detector at center-of-mass energies between 4.178 and 4.226 GeV, an amplitude analysis of the decay D-s(+) -> pi(+)pi(0)pi(0 ) is performed, and the relative fractions and phases of different intermediate processes are determined. The absolute branching fraction of the decay D-s(+) -> pi(+)pi(0)pi(0)is measured to be (0.50 +/- 0.04(stat) 0.02(syst) )%. The absolute branching fraction of the intermediate process D-s(+) -> f(0)(980)pi(+), f(0)(980) ->pi(0)pi(0 ), is determined to be (0.28 +/- 0.04(stat) +/- 0.04(syst))%.
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| 27. |
- Ablikim, M., et al.
(författare)
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Amplitude analysis of D+-> K-S(0)pi(+)pi(+)pi(-)
- 2019
-
Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 100:7
-
Tidskriftsartikel (refereegranskat)abstract
- The decay D+-> K-S(0)pi(+)pi(+)pi(-) is studied with an amplitude analysis using a data set of 2.93 fb(-1) of e(+)e(-) collisions at the psi(3770) peak accumulated by the BESIII detector. Intermediate states and nonresonant components, and their relative fractions and phases, have been determined. The significant amplitudes, which contribute to the model that best fits the data, are composed of five quasitwo-body decays K(S)(0)a(1)(1260)(+), (K) over bar (1)(1270)(0)pi(+) (K) over bar (1)(1400)(0)pi(+), (K) over bar (1)(1650)(0)pi(+), and (K) over bar (1460)(0)pi(+), a three-body decay K-S(0)pi(+)rho(0), as well as a nonresonant component K-S(0)pi(+)pi(+)pi(-). The dominant amplitude is K(S)(0)a(1)(1260)(+), with a fit fraction of (40.3 +/- 2.1 +/- 2.9)%, where the first and second uncertainties are statistical and systematic, respectively.
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| 28. |
- Ablikim, M., et al.
(författare)
-
Amplitude analysis of D-s(+) -> pi(+) pi(-) pi(+)
- 2022
-
Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 106:11
-
Tidskriftsartikel (refereegranskat)abstract
- Utilizing the data set corresponding to an integrated luminosity of 3.19 fb(-1) collected by the BESIII detector at a center-of-mass energy of 4.178 GeV, we perform an amplitude analysis of the D-s(+) -> pi(+) pi(-) pi(+) decay. The sample contains 13,797 candidates with a signal purity of similar to 80%. The amplitude and phase of the contributing pi pi S wave are measured based on a quasi-model-independent approach, along with the amplitudes and phases of the P and D waves parametrized by Breit-Wigner models. The fit fractions of different intermediate decay channels are also reported.
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| 29. |
- Ablikim, M., et al.
(författare)
-
Complete Measurement of the Λ Electromagnetic Form Factors
- 2019
-
Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 123:12
-
Tidskriftsartikel (refereegranskat)abstract
- The exclusive process e(+)e(-) -> Lambda(Lambda) over bar, with Lambda -> p pi(-) and (Lambda) over bar -> (p) over bar pi(+), has been studied at root s = 2.396 GeV for measurement of the timelike Lambda electric and magnetic form factors, G(E) and G(M). A data sample, corresponding to an integrated luminosity of 66.9 pb(-1), was collected with the BESIII detector for this purpose. A multidimensional analysis with a complete decomposition of the spin structure of the reaction enables a determination of the modulus of the ratio R = vertical bar G(E)/G(M)vertical bar and, for the first time for any baryon, the relative phase Delta Phi = Phi(E) - Phi(M). The resulting values are R = 0.96 +/- 0.14(stat) +/- 0.02(syst) and Phi(F) = 37 degrees +/- 12 degrees (stat) +/- 6 degrees (syst), respectively. These are obtained using the recently established and most precise value of the asymmetry parameter alpha(Lambda) = 0.750 +/- 0.010 measured by BESIII. In addition, the cross section is measured with unprecedented precision to be sigma = 118.7 +/- 5.3(stat) +/- 5.1(syst) pb, which corresponds to an effective form factor of vertical bar G vertical bar = 0.123 +/- 0.003(stat) +/- 0.003(syst). The contribution from two-photon exchange is found to be negligible. Our result enables the first complete determination of baryon timelike electromagnetic form factors.
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| 30. |
- Ablikim, M., et al.
(författare)
-
Cross section measurement of e(+) e(-) -> eta ' J/psi from root S=4.178 to 4.600 GeV
- 2020
-
Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 101:1
-
Tidskriftsartikel (refereegranskat)abstract
- The cross section of the process e(+) e(-) -> eta ' J/ psi is measured at center-of-mass (c.m.) energies from root S = 4.178 to 4.600 GeV using data samples corresponding to a total integrated luminosity of 11 fb(-1) collected with the BESIII detector operating at the BEPCII storage ring. The dependence of the cross section on root S shows an enhancement around 4.2 GeV. While the shape of the cross section cannot be fully explained with a single psi(4160) or psi(4260) state, a coherent sum of the two states does provide a reasonable description of the data.
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| 31. |
- Ablikim, M., et al.
(författare)
-
Cross section measurement of e(+)e(-) -> (KSKL0)-K-0 at root s=2.00-3.08 GeV
- 2021
-
Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 104:9
-
Tidskriftsartikel (refereegranskat)abstract
- The cross sections of the process e(+)e(-) -> (KSKL0)-K-0 are measured at fifteen center-of-mass energies root s from 2.00 to 3.08 GeV with a total integrated luminosity of 582 pb(-1) and using the BESIII detector at the Beijing Electron Positron Collider. The results are found to be consistent with those obtained by BABAR. A resonant structure around 2.2 GeV is observed, with a mass and width of 2273.7 +/- 5.7 +/- 19.3 MeV/c(2) and 86 +/- 44 +/- 51 MeV, respectively, where the first uncertainties are statistical and the second ones are systematic. The product of its radiative width (Gamma(e+e-)) with its branching fraction to (KSKL0)-K-0 (Br-KS0KL0) is 0.9 +/- 0.6 +/- 0.7 eV.
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| 32. |
- Ablikim, M., et al.
(författare)
-
Cross section measurement of e(+)e(-) -> p(p)over-bar eta and e(+)e(-) -> p(p)over-bar omega at center-of-mass energies between 3.773 GeV and 4.6 GeV
- 2021
-
Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 104:9
-
Tidskriftsartikel (refereegranskat)abstract
- Based on 14.7 fb(-1) of e(+)e(-) annihilation data collected with the BESIII detector at the BEPCII collider at 17 different center-of-mass energies between 3.7730 GeV and 4.5995 GeV, Born cross sections of the two processes e(+)e(-) -> p (p) over bar eta and e(+)e(-) -> p (p) over bar omega are measured for the first time. No indication of resonant production through a vector state V is observed, and upper limits on the Born cross sections of e(+)e(-) -> p (p) over bar eta and e(+)e(-) -> p (p) over bar omega at the 90% confidence level are calculated for a large parameter space in resonance masses and widths. For the current world average parameters of the psi(4230) of m = 4.2187 GeV=c(2) and Gamma = 44 MeV, we find upper limits on resonant production of the p (p) over bar eta and p (p) over bar omega final states of 7.5 pb and 10.4 pb at the 90% CL, respectively.
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| 33. |
- Ablikim, M., et al.
(författare)
-
Cross section measurement of e+e- → π+π-ψ(3686) from √s = 4.0076 GeV to 4.6984 GeV
- 2021
-
Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 104:5
-
Tidskriftsartikel (refereegranskat)abstract
- Using data samples with a total integrated luminosity of 20.1 fb(-1) collected by the BESIII detector operating at the BEPCII collider, the cross section of the process e(+) e(-) -> pi(+) pi(-) psi(3686) is measured at center-of-mass energies between 4.0076 and 4.6984 GeV. The measured cross section is consistent with previous results, and with much improved precision. A fit to the measured energy-dependent cross section, which includes three Breit-Wigner functions and a nonresonant contribution, confirms the existence of the charmonium-like states Y(4220), Y(4390), and Y(4660). This is the first observation of the Y(4660) at the BESIII experiment.
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| 34. |
- Ablikim, M., et al.
(författare)
-
Cross section measurements of e+e- -> K+ K- K+ K- and ΦK+ K- at center-of-mass energies from 2.10 to 3.08 GeV
- 2019
-
Ingår i: Physical Review D. - 2470-0010 .- 2470-0029. ; 100:3
-
Tidskriftsartikel (refereegranskat)abstract
- We measure the Born cross sections of the process e(+)e(-) -> K+ K- K+ K- at center-of-mass (c.m.) energies, root s, between 2.100 and 3.080 GeV. The data were collected using the BESIII detector at the BEPCII collider. An enhancement at root s = 2.232 GeV is observed, very close to the e(+)e(-) -> Lambda(Lambda) over bar production threshold. A similar enhancement at the same c.m. energy is observed in the e(+)e(-) -> phi K+ K- cross section. The energy dependence of the K+ K- K+ K- and phi K+ K- cross sections differs significantly from that of e(+)e(-) -> phi pi(+)pi(-).
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| 35. |
- Ablikim, M., et al.
(författare)
-
Cross section measurements of e(+) e(-) -> omega chi(c0) from root s=4.178 to 4.278 GeV
- 2019
-
Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 99:9
-
Tidskriftsartikel (refereegranskat)abstract
- The cross section of the process e(+)e(-) -> omega chi(C0) is measured at center -of -mass energies from root s = 4.178 to 4.278 GeV using a data sample of 7 fb(-1) collected with the BESIII detector operating at the BEPCII storage ring. The dependence of the cross section on root s shows a resonant structure with mass of (4218.5 +/- 1.6(stat) +/- 4.0(syst)) MeV/c(2) and width of (28.2 +/- 3.9(stat) +/- 1.6(syst)) MeV, respectively. This observation confirms and improves upon the result of a previous study. The angular distribution of the e(+) e(-) ->omega chi(C0) process is extracted for the first time.
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| 36. |
- Ablikim, M., et al.
(författare)
-
Cross-section measurements of e plus e- ? ?K plus K - and e plus e- ??K0SK0S at center-of-mass energies between 3.7730 GeV and 4.7008 GeV
- 2023
-
Ingår i: Physical Review D. - : AMER PHYSICAL SOC. - 2470-0010 .- 2470-0029. ; 108:3
-
Tidskriftsartikel (refereegranskat)abstract
- Based on 22.7 fb-1 of e+e- annihilation data collected at 33 different center-of-mass energies between 3.7730 and 4.7008 GeV with the BESIII detector at the BEPCII collider, Born cross sections of the two processes e+e- & RARR; & phi;K+K- and e+e- & RARR; & phi;K0SK0S are measured for the first time. No indication of resonant production through an intermediate vector state V is observed, and the upper limits on the product of the electronic width & UGamma;e+e- and the branching fraction Br(V & RARR; & phi;K over bar K) of the processes e+e- & RARR; V & RARR; & phi;K+K- and e+e- & RARR; V & RARR; & phi;K0SK0S at the 90% confidence level are obtained for a large parameter space in resonance masses and widths. For the current world average mass and width of the & psi;(4230) of m = 4.2187 GeV=c2 and & UGamma; = 44 MeV, we set upper limits on the & phi;K+K- and & phi;K0SK0S final states of 1.75 and 0.47 eV at the 90% confidence level, respectively.
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| 37. |
- Ablikim, M., et al.
(författare)
-
Cross section measurements of the e(+)e(-) -> D*D+*(-) and e(+)e(-) -> D*D-+(-) processes at center-of-mass energies from 4.085 to 4.600 GeV
- 2022
-
Ingår i: Journal of High Energy Physics (JHEP). - : Springer Nature. - 1126-6708 .- 1029-8479. ; :5
-
Tidskriftsartikel (refereegranskat)abstract
- The Born cross sections of the e(+)e(-) -> D*D+*(-) and e(+)e(-) -> D*D-+(-) processes are measured using e(+)e(-) collision data collected with the BESIII experiment at center-of-mass energies from 4.085 to 4.600 GeV, corresponding to an integrated luminosity of 15.7 fb(-1). The results are consistent with and more precise than the previous measurements by the Belle, Babar and CLEO collaborations. The measurements are essential for understanding the nature of vector charmonium and charmonium-like states.
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| 38. |
- Ablikim, M., et al.
(författare)
-
Cross section measurements of the processes e+e− → ωπ0 and ωη at center-of-mass energies between 3.773 and 4.701 GeV
- 2022
-
Ingår i: Journal of High Energy Physics (JHEP). - : Springer Nature. - 1126-6708 .- 1029-8479. ; :7
-
Tidskriftsartikel (refereegranskat)abstract
- The Born cross sections of the processes e(+)e(-) -> omega pi(0) and e(+)e(-) -> omega eta are measured at center-of-mass energies between 3.773 and 4.701 GeV using a total integrated luminosity of 22.7 fb(-1) collected with the BESIII detector operating at the BEPCII collider. A simple s(-n) dependence for the continuum process can describe the measured Born cross sections. No significant contributions from the psi(4160), Y(4230), Y(4360), psi(4415), Y(4660) resonances are found, which indicates relative small branching fractions for these resonances into the omega pi(0) and omega eta final states.
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| 39. |
- Ablikim, M., et al.
(författare)
-
Cross sections for the reactions e+e−→K+K−π+π−(π0), K+K−K+K−(π0), π+π−π+π−(π0), p¯pπ+π−(π0) in the energy region between 3.773 and 4.600 GeV
- 2021
-
Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 104:11
-
Tidskriftsartikel (refereegranskat)abstract
- Using the data samples collected in the energy range from 3.773 to 4.600 GeV with the BESIII detector at the BEPCII collider, we measure the dressed cross sections as a function of center-of-mass energy for e(+)e(-) -> K+K- pi(+)pi(-) (pi(0)), K+K-K+K- (pi(0)), pi(+)pi(-) pi(+)pi(-) (pi(0)), and p (p) over bar pi(+)pi(-)(pi(0)). The cross sections for e(+)e(-) -> K+K-K+K- pi(0), p (p) over bar pi(+)pi(-)(pi(0)) are the first measurements. Cross sections for the other five channels are much more precise than previous results in this energy region. We also search for charmonium and charmonium-like resonances, such as the Y(4230), decaying into the same final states. We find evidence of the psi(4040) decaying to pi(+)pi(-) pi(+)pi(-) pi(0) with a statistical significance of 3.6 sigma. Upper limits are provided for other decays since no clear signals are observed.
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| 40. |
- Ablikim, M., et al.
(författare)
-
Determination of Spin-Parity Quantum Numbers for the Narrow Structure near the p¯Λ Threshold in e+e−→pK−¯Λ+c.c.
- 2023
-
Ingår i: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 131:15
-
Tidskriftsartikel (refereegranskat)abstract
- A narrow structure in the p¯Λ system near the mass threshold, named as X(2085), is observed in the process e+e−→pK−¯Λ with a statistical significance greater than 20σ. Its spin and parity are determined for the first time to be JP=1+ in an amplitude analysis, with a statistical significance greater than 5σ over other quantum numbers (0−,1− and 2+). The pole positions of X(2085) are measured to be Mpole=(2084+4−2±9) MeV and Γpole=(58+4−3±25) MeV, where the first uncertainties are statistical and the second ones are systematic. The analysis is based on the study of the process e+e−→pK−¯Λ and uses the data samples collected with the BESIII detector at the center-of-mass energies √s=4.008, 4.178, 4.226, 4.258, 4.416, and 4.682 GeV with a total integrated luminosity of 8.35 fb−1.
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| 41. |
- Ablikim, M., et al.
(författare)
-
Determination of Strong-Phase Parameters in D -> K-S,L(0)pi(+)pi(-)
- 2020
-
Ingår i: Physical Review Letters. - : AMER PHYSICAL SOC. - 0031-9007 .- 1079-7114. ; 124:24
-
Tidskriftsartikel (refereegranskat)abstract
- We report the most precise measurements to date of the strong-phase parameters between D-0 and (D) over bar (0) decays to K-S,L(0)pi(+)pi(-) using a sample of 2.93 fb(-1) of e(+) e(-) annihilation data collected at a center-of-mass energy of 3.773 GeV with the BESIII detector at the BEPCII collider. Our results provide the key inputs for a binned model-independent determination of the Cabibbo-Kobayashi-Maskawa angle gamma/phi(3) with B decays. Using our results, the decay model sensitivity to the gamma/phi(3 )measurement is expected to be between 0.7 degrees and 1.2 degrees, approximately a factor of three smaller than that achievable with previous measurements, based on the studies of the simulated data. The improved precision of this work ensures that measurements of gamma/phi(3) will not be limited by knowledge of strong phases for the next decade. Furthermore, our results provide critical input for other flavor-physics investigations, including charm mixing, other measurements of CP violation, and the measurement of strong-phase parameters for other D-decay modes.
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| 42. |
- Ablikim, M., et al.
(författare)
-
Determination of the absolute branching fractions of D0 → K-e+νe and D+ → K0e+νe
- 2021
-
Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 104:5
-
Tidskriftsartikel (refereegranskat)abstract
- Using 2.93 fb(-1) of e(+)e(-) collision data collected with the BESIII detector at a center-of-mass energy of 3.773 GeV, we measure the absolute branching fractions of the decays D-0 -> K(-)e(+)nu(e) and D+ -> (K) over bar (0)e(+)nu(e) to be (3.567 +/- 0.031(stat) +/- 0.025(syst))% and (8.68 +/- 0.14(stat) +/- 0.16(syst))%, respectively. Starting with the process e(+)e(- ) -> D (D) over bar, a new reconstruction method is employed to select events that contain candidates for both D -> (K) over bare(+)nu(e) and (D) over bar -> Ke(-)(nu) over bar (e) decays. The branching fractions reported in this work are consistent within uncertainties with previous BESIII measurements that selected events containing D -> (K) over bare(+)nu(e) and hadronic (D) over bar decays. Combining our results with the lifetimes of the D degrees and D+ mesons and the previous BESIII measurements leads to a ratio of the two decay partial widths of (Gamma) over bar (D0 -> K-e+)(nu e)/(Gamma) over bar (D+ -> (K) over bar 0e+)(nu e) = 1.039 +/- 0.021. This ratio supports isospin symmetry in the D-0 -> K(-)e(+)nu(e) and D+ -> (K) over bar (0)e(+)nu(e) decays within 1.9 sigma.
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| 43. |
- Ablikim, M., et al.
(författare)
-
Determination of the CP-even fraction of D0? : K0Sp+p-p0
- 2023
-
Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 108:3
-
Tidskriftsartikel (refereegranskat)abstract
- Quantum-correlated D D over bar pairs collected by the BESIII experiment at the & psi;(3770) resonance corresponding to an integrated luminosity of 2.93 fb-1 are used to study the D0 & RARR; K0S & pi;+& pi;- & pi;0 decay mode. The CP-even fraction of D0 & RARR; K0S & pi;+& pi;- & pi;0 decays is determined to be 0.235 & PLUSMN; 0.010 & PLUSMN; 0.002, where the first uncertainty is statistical and the second is systematic.
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| 44. |
- Ablikim, M., et al.
(författare)
-
Determination of the ∑+ Timelike Electromagnetic Form Factors
- 2024
-
Ingår i: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 132:8
-
Tidskriftsartikel (refereegranskat)abstract
- Based on data samples collected with the BESIII detector at the BEPCII collider, the process e+e- → Σ+Σ− (over bar) is studied at center -of -mass energies √s = 2.3960, 2.6454, and 2.9000 GeV. Using a fully differential angular description of the final state particles, both the relative magnitude and phase information of the Σ+ electromagnetic form factors in the timelike region are extracted. The relative phase between the electric and magnetic form factors is determined to be sin ΔΦ = -0.67 ± 0.29(stat) ± 0.18(syst) at √s = 2.3960 GeV, AO = 55° ± 19°(stat) ± 14°(syst) at √s = 2.6454 GeV, and 78° ± 22°(stat) ± 9°(syst) at √s = 2.9000 GeV. For the first time, the phase of the hyperon electromagnetic form factors is explored in a wide range of four -momentum transfer. The evolution of the phase along with fourmomentum transfer is an important input for understanding its asymptotic behavior and the dynamics of baryons.
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| 45. |
- Ablikim, M., et al.
(författare)
-
Determination of the Λ+c spin via the reaction e+e− → Λc¯Λc
- 2021
-
Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 103:9
-
Tidskriftsartikel (refereegranskat)abstract
- We report on a comparison of two possible Λ+c spin hypotheses, J=½ and 3/2, via the process e+e− → Λ+c¯Λ−c, using the angular distributions of Λ+c decays into pK0S, Λπ+, Σ0π+, and Σ+π0. The data were recorded at √s=4.6 GeV with the BESIII detector and correspond to an integrated luminosity of 587 pb−1. The Λ+c spin is determined to be J=½, with this value favored over the 3/2 hypothesis with a significance corresponding to more than 6 Gaussian standard deviations.
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| 46. |
- Ablikim, M., et al.
(författare)
-
Direct Measurement of the Branching Fractions B(psi(3686) -> J/psi X) and B(psi(3770) -> J/psi X), and Observation of the State R(3760) in e(+)e(-) -> J/psi X
- 2021
-
Ingår i: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 127:8
-
Tidskriftsartikel (refereegranskat)abstract
- We report a measurement of the observed cross sections of e(+)e(-) -> J/psi X based on 3.21 fb(-1) of data accumulated at energies from 3.645 to 3.891 GeV with the BESIII detector operated at the BEPCII collider. In analysis of the cross sections, we measured the decay branching fractions of B(psi(3686 -> J/psi X) = (64.4 +/- 0.6 +/- 1.6)% and B(psi(3770) -> J/psi X) = (0.5 +/- 0.2 +/- 0.1)% for the first time. The energy-dependent line shape of these cross sections cannot be well described by two Breit-Wigner (BW) amplitudes of the expected decays psi(3686) -> J/psi X and psi(3770) -> J/psi X. Instead, it can be better described with one more BW amplitude of the decay R(3760) -> J/psi X. Under this assumption, we extracted the R(3760) mass M-R(3760) = 3766.2 +/- 3.8 +/- 0.4 MeV/c(2), total width Gamma(tot)(R(3760)) = 22.2 +/- 5.9 +/- 1.4 MeV, and product of leptonic width and decay branching fraction Gamma(ee)(R(3760)) B[R(3760) -> J/psi X] = (79.4 +/- 85.5 +/- 11.7) eV. The significance of the R(3760) is 5.3 sigma. The first uncertainties of these measured quantities are from fits to the cross sections and second systematic.
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| 47. |
- Ablikim, M., et al.
(författare)
-
Evidence for a Neutral Near-Threshold Structure in the K0S Recoil-Mass Spectra in e+e− → K0SD+sD*− and e+e− → K0SD*s+D−
- 2022
-
Ingår i: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 129:11
-
Tidskriftsartikel (refereegranskat)abstract
- We study the processes e+e− → K0SD+sD*− and e+e− → K0SD*s+D−, as well as their charge conjugated processes, at five center-of-mass energies between 4.628 and 4.699 GeV, using data samples corresponding to an integrated luminosity of 3.8 fb−1 collected by the BESIII detector at the BEPCII storage ring. Based on a partial reconstruction technique, we find evidence of a structure near the thresholds for D+sD*− and D*s+D− production in the K0S recoil-mass spectrum, which we refer to as the Zcs(3985)0. Fitting with a Breit-Wigner line shape, we find the mass of the structure to be (3992.2±1.7±1.6) MeV/c2 and the width to be (7.7+4.1−3.8±4.3) MeV, where the first uncertainties are statistical and the second are systematic. The significance of the Zcs(3985)0 signal is found to be 4.6σ including both the statistical and systematic uncertainty. We report the Born cross section multiplied by the branching fraction at different energy points. The mass of the Zcs(3985)0 is close to that of the Zcs(3985)+. Assuming SU(3) symmetry, the cross section of the neutral channel is consistent with that of the charged one. Hence, we conclude that the Zcs(3985)0 is the isospin partner of the Zcs(3985)+.
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| 48. |
- Ablikim, M., et al.
(författare)
-
Evidence for the Cusp Effect in η' Decays into ηπ0π0
- 2023
-
Ingår i: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 130:8
-
Tidskriftsartikel (refereegranskat)abstract
- Using a sample of 4.3 x 105 eta' -> eta pi 0 pi 0 events selected from the ten billion J=psi event dataset collected with the BESIII detector, we study the decay eta' -> eta pi 0 pi 0 within the framework of nonrelativistic effective field theory. Evidence for a structure at pi+pi- mass threshold is observed in the invariant mass spectrum of pi 0 pi 0 with a statistical significance of around 3.5 sigma, which is consistent with the cusp effect as predicted by the nonrelativistic effective field theory. After introducing the amplitude for describing the cusp effect, the pi pi scattering length combination a0 - a2 is determined to be 0.226 10.060stat 10.013syst, which is in good agreement with theoretical calculation of 0.2644 10.0051.
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| 49. |
- Ablikim, M., et al.
(författare)
-
Evidence for the eta(c)(2S) -> pi(+)pi(-)eta decay
- 2023
-
Ingår i: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 107:5
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Tidskriftsartikel (refereegranskat)abstract
- The decay eta(c)(2S) -> pi(+)pi(-)eta is searched for through the radiative transition psi(3686) -> gamma eta(c)(2S) using 448 million psi(3686) events accumulated at the BESIII detector. The first evidence of eta(c)(2S) -> pi(+)pi(-)eta is found with a statistical significance of 3.5 sigma. The product of the branching fractions of psi(3686) -> gamma eta(c)(2S) and eta(c)(2S) -> pi(+)pi(-)eta is measured to be Br(psi(3686) -> gamma eta(c)(2S)) x Br(eta(c)(2S) -> pi(+)pi(-)eta) = (2.97 +/- 0.81 +/- 0.26) x 10(-6), where the first uncertainty is statistical and the second one is systematic. The branching fraction of the decay eta(c)(2S) -> pi(+)pi(-)eta is determined to be Br(eta(c)(2S) -> pi(+)pi(-)eta) = (42.4 +/- 11.6 +/- 3.8 +/- 30.3) x 10(-4), where the third uncertainty is transferred from the uncertainty of the branching fraction of psi(3686) -> gamma eta(c)(2S).
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| 50. |
- Ablikim, M., et al.
(författare)
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First direct measurement of the absolute branching fraction of Sigma(+) -> Lambda e(+)upsilon(e)
- 2023
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Ingår i: Physical Review D. - : American Physical Society (APS). - 2470-0010 .- 2470-0029. ; 107:7
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Tidskriftsartikel (refereegranskat)abstract
- The first direct measurement of the absolute branching fraction of Sigma(+) -> Lambda e(+)nu(e) is reported based on an e(+) e(-) annihilation sample of (10087 +/- 44) x 10(6) J/psi events collected with the BESIII detector at root s = 3.097 GeV. The branching fraction is determined to be B(Sigma(+)-> Lambda e(+)nu(e))=2.93 +/- 0.74 (stat) +/- 0.13(syst)] x 10(-5), which is the most precise measurement obtained in a single experiment to date and also the first result obtained at a collider experiment. Combining this result with the world average of B(Sigma(-)-> Lambda e(-) (nu) over bar (e). and the lifetimes of Sigma(+/-), the ratio, Gamma (Sigma(-) ->Lambda e(-) (nu) over bar (e) /Sigma(+) -> Lambda e(+) (nu) over bar (e), is determined to be 1.06 +/- 0.28, which is within 1.8 standard deviations of the value expected in the absence of second-class currents.
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