86 results on '"Fegan, S."'
Search Results
2. First Measurement Using Elliptically Polarized Photons of the Double-Polarization Observable E for γp→pπ^{0} and γp→nπ^{+}.
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Afzal F, Spieker K, Hurck P, Abt S, Achenbach P, Adlarson P, Ahmed Z, Akondi CS, Annand JRM, Arends HJ, Bashkanov M, Beck R, Biroth M, Borisov N, Braghieri A, Briscoe WJ, Cividini F, Collicott C, Costanza S, Denig A, Dieterle M, Downie EJ, Drexler P, Fegan S, Gardner S, Ghosal D, Glazier DI, Gorodnov I, Gradl W, Gurevich D, Heijkenskjöld L, Hornidge D, Huber GM, Kashevarov VL, Kay SJD, Korolija M, Krusche B, Lazarev A, Livingston K, Lutterer S, MacGregor IJD, Macrae RG, Manley DM, Martel PP, Miskimen R, Mocanu M, Mornacchi E, Mullen C, Neganov A, Neiser A, Oberle M, Ostrick M, Otte PB, Paudyal D, Pedroni P, Powell A, Reicherz G, Rostomyan T, Sfienti C, Sokhoyan V, Steffen O, Strakovsky II, Strub T, Supek I, Thiel A, Thiel M, Thomas A, Usov YA, Wagner S, Walford NK, Watts DP, Werthmüller D, Wettig J, Witthauer L, Wolfes M, and Zachariou N
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We report the measurement of the helicity asymmetry E for the pπ^{0} and nπ^{+} final states using, for the first time, an elliptically polarized photon beam in combination with a longitudinally polarized target at the Crystal Ball experiment at MAMI. The results agree very well with data that were taken with a circularly polarized photon beam, showing that it is possible to simultaneously measure polarization observables that require linearly (e.g., G) and circularly polarized photons (e.g., E) and a longitudinally polarized target. The new data cover a photon energy range 270-1400 MeV for the pπ^{0} final state (230-842 MeV for the nπ^{+} final state) and the full range of pion polar angles, θ, providing the most precise measurement of the observable E. A moment analysis gives a clear observation of the pη cusp in the pπ^{0} final state.
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- 2024
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3. Vulval squamous cell cancer - does precursor lesion margin status affect recurrence-free survival after optimal surgical resection for early-stage disease?
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Durden AA, Sanderson P, Ghaoui N, Fegan S, Martin C, Thum C, and May J
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- Humans, Female, Retrospective Studies, Middle Aged, Aged, Adult, Neoplasm Staging, Aged, 80 and over, Disease-Free Survival, Precancerous Conditions surgery, Precancerous Conditions pathology, Vulvar Neoplasms surgery, Vulvar Neoplasms pathology, Vulvar Neoplasms mortality, Margins of Excision, Carcinoma, Squamous Cell surgery, Carcinoma, Squamous Cell pathology, Carcinoma, Squamous Cell mortality, Neoplasm Recurrence, Local pathology
- Abstract
Objectives: Vulval cancer accounts for around 4% of all gynaecological malignancies and most tumours ( > 90%) are of a squamous cell histotype. Most lesions arise on a background of differentiated VIN (dVIN) or lichen sclerosus (LS). Surgical treatment has undergone a paradigm shift with less radical surgery being attempted to preserve vulval structure and function, without compromising oncological outcome., Material and Methods: In this single site retrospective analysis, we consider the data from a tertiary oncology unit, to assess progression-free survival based on the presence of a precursor lesion at the margin of resection.123 patients with FIGO stage 1 vulvar SCC (n = 33 1A, n = 90 1B) were included., Results: One Hundred Five patients (85%) had an associated precursor lesion (dVIN and/or LS). Within the follow-up period, 33 patients (26.8%) had invasive recurrence, of which 24 (72.7%) had surgical resection margins which were positive for a precursor lesion. In patients with an acceptable microscopically clear invasive resection margin of > 2 mm the presence of a precursor lesion at the margin conveyed a higher risk of malignant recurrence when compared to those with completely clear margins (HR = 2.42; 95% CI 1.14-5.16)., Conclusions: This study adds to the available literature emphasising the clinical significance of dVIN or LS at the surgical margin of optimally resected disease. In those who have marginal involvement of a precancerous lesion, increased surveillance should be considered. Future work should explore the need for additional adjuvant therapy in this cohort.
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- 2024
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4. First Measurement of Hard Exclusive π^{-}Δ^{++} Electroproduction Beam-Spin Asymmetries off the Proton.
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Diehl S, Trotta N, Joo K, Achenbach P, Akbar Z, Armstrong WR, Atac H, Avakian H, Baashen L, Baltzell NA, Barion L, Bashkanov M, Battaglieri M, Bedlinskiy I, Benmokhtar F, Bianconi A, Biselli AS, Bossù F, Brinkmann KT, Briscoe WJ, Bulumulla D, Burkert V, Capobianco R, Carman DS, Carvajal JC, Celentano A, Charles G, Chatagnon P, Chesnokov V, Ciullo G, Cole PL, Contalbrigo M, Costantini G, Crede V, D'Angelo A, Dashyan N, De Vita R, Deur A, Djalali C, Dupre R, Ehrhart M, El Alaoui A, El Fassi L, Elouadrhiri L, Fegan S, Filippi A, Gavalian G, Glazier DI, Golubenko AA, Gosta G, Gothe RW, Gotra Y, Griffioen K, Hafidi K, Hakobyan H, Hattawy M, Hayward TB, Heddle D, Hobart A, Holtrop M, Illari I, Ireland DG, Isupov EL, Jo HS, Johnston R, Keller D, Khachatryan M, Khanal A, Kim A, Kim W, Klimenko V, Kripko A, Kubarovsky V, Kuhn SE, Lagerquist V, Lanza L, Leali M, Lee S, Lenisa P, Li X, MacGregor IJD, Marchand D, Mascagna V, Matousek G, McKinnon B, McLauchlin C, Meziani ZE, Migliorati S, Milner RG, Mineeva T, Mirazita M, Mokeev V, Moran P, Munoz Camacho C, Naidoo P, Neupane K, Niccolai S, Niculescu G, Osipenko M, Pandey P, Paolone M, Pappalardo LL, Paremuzyan R, Paul SJ, Phelps W, Pilleux N, Pokhrel M, Poudel J, Price JW, Prok Y, Radic A, Raue BA, Reed T, Richards J, Ripani M, Ritman J, Rossi P, Sabatié F, Salgado C, Schadmand S, Schmidt A, Sharabian YG, Shrestha U, Sokhan D, Sparveris N, Spreafico M, Stepanyan S, Strakovsky I, Strauch S, Turisini M, Tyson R, Ungaro M, Vallarino S, Venturelli L, Voskanyan H, Voutier E, Watts DP, Wei X, Williams R, Wishart R, Wood MH, Yurov M, Zachariou N, Zhao ZW, and Zurek M
- Abstract
The polarized cross-section ratio σ_{LT^{'}}/σ_{0} from hard exclusive π^{-}Δ^{++} electroproduction off an unpolarized hydrogen target has been extracted based on beam-spin asymmetry measurements using a 10.2 GeV/10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. The study, which provides the first observation of this channel in the deep-inelastic regime, focuses on very forward-pion kinematics in the valence regime, and photon virtualities ranging from 1.5 GeV^{2} up to 7 GeV^{2}. The reaction provides a novel access to the d-quark content of the nucleon and to p→Δ^{++} transition generalized parton distributions. A comparison to existing results for hard exclusive π^{+}n and π^{0}p electroproduction is provided, which shows a clear impact of the excitation mechanism, encoded in transition generalized parton distributions, on the asymmetry.
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- 2023
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5. First CLAS12 Measurement of Deeply Virtual Compton Scattering Beam-Spin Asymmetries in the Extended Valence Region.
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Christiaens G, Defurne M, Sokhan D, Achenbach P, Akbar Z, Amaryan MJ, Atac H, Avakian H, Gayoso CA, Baashen L, Baltzell NA, Barion L, Bashkanov M, Battaglieri M, Bedlinskiy I, Benkel B, Benmokhtar F, Bianconi A, Biselli AS, Bondi M, Booth WA, Bossù F, Boiarinov S, Brinkmann KT, Briscoe WJ, Bueltmann S, Bulumulla D, Burkert VD, Cao T, Carman DS, Carvajal JC, Celentano A, Chatagnon P, Chesnokov V, Chetry T, Ciullo G, Clash G, Cole PL, Contalbrigo M, Costantini G, D'Angelo A, Dashyan N, De Vita R, Deur A, Diehl S, Dilks C, Djalali C, Dupre R, Egiyan H, Ehrhart M, Alaoui AE, Fassi LE, Elouadrhiri L, Fegan S, Filippi A, Gates K, Gavalian G, Ghandilyan Y, Gilfoyle GP, Girod FX, Glazier DI, Golubenko AA, Gosta G, Gothe RW, Gotra Y, Griffioen KA, Guidal M, Hafidi K, Hakobyan H, Hattawy M, Hauenstein F, Hayward TB, Heddle D, Hobart A, Holmberg DE, Holtrop M, Ilieva Y, Ireland DG, Isupov EL, Jo HS, Keller D, Khachatryan M, Khanal A, Kim W, Kripko A, Kubarovsky V, Kuhn SE, Lagerquist V, Lanza L, Kabir ML, Leali M, Lee S, Lenisa P, Li X, Livingston K, MacGregor IJD, Marchand D, Mascagna V, Matousek G, McKinnon B, McLauchlin C, Meziani ZE, Migliorati S, Milner RG, Mineeva T, Mirazita M, Mokeev V, Molina E, Camacho CM, Nadel-Turonski P, Naidoo P, Neupane K, Niccolai S, Nicol M, Niculescu G, Osipenko M, Ouillon M, Pandey P, Paolone M, Pappalardo LL, Paremuzyan R, Pasyuk E, Paul SJ, Phelps W, Pilleux N, Pokhrel M, Poudel J, Price JW, Prok Y, Radic A, Ramasubramanian N, Raue BA, Reed T, Richards J, Ripani M, Ritman J, Rossi P, Sabatié F, Salgado C, Schadmand S, Schmidt A, Scott MBC, Sharabian YG, Shirokov EV, Shrestha U, Simmerling P, Sparveris N, Spreafico M, Stepanyan S, Strakovsky II, Strauch S, Tan JA, Trotta N, Turisini M, Tyson R, Ungaro M, Vallarino S, Venturelli L, Voskanyan H, Voutier E, Watts DP, Wei X, Williams R, Wishart R, Wood MH, Zachariou N, Zhang J, Zhao ZW, Ziegler V, and Zurek M
- Abstract
Deeply virtual Compton scattering (DVCS) allows one to probe generalized parton distributions describing the 3D structure of the nucleon. We report the first measurement of the DVCS beam-spin asymmetry using the CLAS12 spectrometer with a 10.2 and 10.6 GeV electron beam scattering from unpolarized protons. The results greatly extend the Q^{2} and Bjorken-x phase space beyond the existing data in the valence region and provide 1600 new data points measured with unprecedented statistical uncertainty, setting new, tight constraints for future phenomenological studies.
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- 2023
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6. First Measurement of Λ Electroproduction off Nuclei in the Current and Target Fragmentation Regions.
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Chetry T, El Fassi L, Brooks WK, Dupré R, El Alaoui A, Hafidi K, Achenbach P, Adhikari KP, Akbar Z, Armstrong WR, Arratia M, Atac H, Avakian H, Baashen L, Baltzell NA, Barion L, Bashkanov M, Battaglieri M, Bedlinskiy I, Benkel B, Benmokhtar F, Bianconi A, Biselli AS, Bondi M, Booth WA, Bossù F, Boiarinov S, Brinkmann KT, Briscoe WJ, Bulumulla D, Burkert VD, Carman DS, Carvajal JC, Celentano A, Chatagnon P, Chesnokov V, Ciullo G, Cole PL, Contalbrigo M, Costantini G, D'Angelo A, Dashyan N, De Vita R, Defurne M, Deur A, Diehl S, Djalali C, Egiyan H, Elouadrhiri L, Eugenio P, Fegan S, Filippi A, Gavalian G, Ghandilyan Y, Gilfoyle GP, Glazier DI, Golubenko AA, Gosta G, Gothe RW, Griffioen KA, Guidal M, Guo L, Hakobyan H, Hattawy M, Hayward TB, Heddle D, Hobart A, Holtrop M, Ilieva Y, Ireland DG, Isupov EL, Jenkins D, Jo HS, Kabir ML, Khanal A, Khandaker M, Kim A, Kim W, Klein FJ, Kripko A, Kubarovsky V, Lagerquist V, Lanza L, Leali M, Lee S, Lenisa P, Li X, Livingston K, MacGregor IJD, Marchand D, Mascagna V, McKinnon B, McLauchlin C, Meziani ZE, Migliorati S, Mineeva T, Mirazita M, Mokeev V, Munoz Camacho C, Nadel-Turonski P, Neupane K, Niccolai S, Nicol M, Niculescu G, Osipenko M, Ostrovidov AI, Pandey P, Paolone M, Pappalardo LL, Paremuzyan R, Pasyuk E, Paul SJ, Phelps W, Pilleux N, Pokhrel M, Poudel J, Price JW, Prok Y, Raue BA, Reed T, Richards J, Ripani M, Ritman J, Rosner G, Sabatié F, Salgado C, Schadmand S, Schmidt A, Schumacher RA, Sharabian YG, Shirokov EV, Shrestha U, Simmerling P, Sokhan D, Sparveris N, Stepanyan S, Strakovsky II, Strauch S, Tan JA, Trotta N, Tyson R, Ungaro M, Vallarino S, Venturelli L, Voskanyan H, Voutier E, Wei X, Weinstein LB, Williams R, Wishart R, Wood MH, Yurov M, Zachariou N, Zhao ZW, and Zurek M
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We report results of Λ hyperon production in semi-inclusive deep-inelastic scattering off deuterium, carbon, iron, and lead targets obtained with the CLAS detector and the Continuous Electron Beam Accelerator Facility 5.014 GeV electron beam. These results represent the first measurements of the Λ multiplicity ratio and transverse momentum broadening as a function of the energy fraction (z) in the current and target fragmentation regions. The multiplicity ratio exhibits a strong suppression at high z and an enhancement at low z. The measured transverse momentum broadening is an order of magnitude greater than that seen for light mesons. This indicates that the propagating entity interacts very strongly with the nuclear medium, which suggests that propagation of diquark configurations in the nuclear medium takes place at least part of the time, even at high z. The trends of these results are qualitatively described by the Giessen Boltzmann-Uehling-Uhlenbeck transport model, particularly for the multiplicity ratios. These observations will potentially open a new era of studies of the structure of the nucleon as well as of strange baryons.
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- 2023
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7. Observation of Correlations between Spin and Transverse Momenta in Back-to-Back Dihadron Production at CLAS12.
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Avakian H, Hayward TB, Kotzinian A, Armstrong WR, Atac H, Ayerbe Gayoso C, Baashen L, Baltzell NA, Barion L, Bashkanov M, Battaglieri M, Bedlinskiy I, Benkel B, Benmokhtar F, Bianconi A, Biondo L, Biselli AS, Bondi M, Boiarinov S, Bossù F, Brinkman KT, Briscoe WJ, Brooks WK, Bueltmann S, Bulumulla D, Burkert VD, Capobianco R, Carman DS, Carvajal JC, Celentano A, Chatagnon P, Chesnokov V, Chetry T, Ciullo G, Cole PL, Contalbrigo M, Costantini G, D'Angelo A, Dashyan N, De Vita R, Defurne M, Deur A, Diehl S, Dilks C, Djalali C, Dupre R, Egiyan H, El Alaoui A, El Fassi L, Elouadrhiri L, Fegan S, Filippi A, Forest T, Gates K, Gavalian G, Ghandilyan Y, Glazier DI, Golubenko AA, Gosta G, Gothe RW, Gotra Y, Griffioen KA, Guidal M, Hakobyan H, Hattawy M, Hauenstein F, Heddle D, Hobart A, Holtrop M, Hyde CE, Ilieva Y, Ireland DG, Isupov EL, Jo HS, Johnston R, Joo K, Kabir ML, Keller D, Khachatryan M, Khanal A, Kim A, Kim W, Klimenko V, Kripko A, Kubarovsky V, Kuhn SE, Lagerquist V, Lanza L, Leali M, Lee S, Lenisa P, Li X, MacGregor IJD, Marchand D, Mascagna V, McKinnon B, Migliorati S, Mineeva T, Mirazita M, Mokeev V, Montgomery RA, Munoz Camacho C, Nadel-Turonski P, Naidoo P, Neupane K, Nguyen D, Niccolai S, Nicol M, Niculescu G, Osipenko M, Pandey P, Paolone M, Pappalardo LL, Paremuzyan R, Pasyuk E, Paul SJ, Phelps W, Pilleux N, Pogorelko O, Pokhrel M, Poudel J, Price JW, Prok Y, Raue BA, Reed T, Richards J, Ripani M, Ritman J, Rossi P, Sabatié F, Salgado C, Schmidt A, Sharabian YG, Shirokov EV, Shrestha U, Simmerling P, Sokhan D, Sparveris N, Stepanyan S, Strakovsky II, Strauch S, Tan JA, Trotta N, Tyson R, Ungaro M, Vallarino S, Venturelli L, Voskanyan H, Vossen A, Voutier E, Watts DP, Wei X, Wishart R, Wood MH, Zachariou N, Zhao ZW, and Zurek M
- Abstract
We report the first measurements of deep inelastic scattering spin-dependent azimuthal asymmetries in back-to-back dihadron electroproduction in the deep inelastic scattering process. In this reaction, two hadrons are produced in opposite hemispheres along the z axis in the virtual photon-target nucleon center-of-mass frame, with the first hadron produced in the current-fragmentation region and the second in the target-fragmentation region. The data were taken with longitudinally polarized electron beams of 10.2 and 10.6 GeV incident on an unpolarized liquid-hydrogen target using the CLAS12 spectrometer at Jefferson Lab. Observed nonzero sinΔϕ modulations in ep→e^{'}pπ^{+}X events, where Δϕ is the difference of the azimuthal angles of the proton and pion in the virtual photon and target nucleon center-of-mass frame, indicate that correlations between the spin and transverse momenta of hadrons produced in the target- and current-fragmentation regions may be significant. The measured beam-spin asymmetries provide a first access in dihadron production to a previously unexplored leading-twist spin- and transverse-momentum-dependent fracture function. The fracture functions describe the hadronization of the target remnant after the hard scattering of a virtual photon off a quark in the target particle and provide a new avenue for studying nucleonic structure and hadronization.
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- 2023
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8. Observation of Azimuth-Dependent Suppression of Hadron Pairs in Electron Scattering off Nuclei.
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Paul SJ, Morán S, Arratia M, El Alaoui A, Hakobyan H, Brooks W, Amaryan MJ, Armstrong WR, Atac H, Baashen L, Baltzell NA, Barion L, Bashkanov M, Battaglieri M, Bedlinskiy I, Benkel B, Benmokhtar F, Bianconi A, Biondo L, Biselli AS, Bondi M, Bossù F, Boiarinov S, Brinkmann KT, Briscoe WJ, Bulumulla D, Burkert VD, Capobianco R, Carman DS, Celentano A, Chesnokov V, Chetry T, Ciullo G, Cole PL, Contalbrigo M, Costantini G, D'Angelo A, Dashyan N, De Vita R, Defurne M, Deur A, Diehl S, Dilks C, Djalali C, Dupre R, Egiyan H, El Fassi L, Eugenio P, Fegan S, Filippi A, Gavalian G, Ghandilyan Y, Gilfoyle GP, Golubenko AA, Gosta G, Gothe RW, Griffioen KA, Guidal M, Hattawy M, Hayward TB, Heddle D, Hobart A, Holtrop M, Ilieva Y, Ireland DG, Isupov EL, Jo HS, Johnston R, Joo K, Joosten S, Keller D, Khanal A, Khandaker M, Kim W, Kripko A, Kubarovsky V, Lagerquist V, Lanza L, Leali M, Lee S, Lenisa P, Li X, Livingston K, MacGregor IJD, Marchand D, Mascagna V, McKinnon B, Meziani ZE, Migliorati S, Milner RG, Mineeva T, Mirazita M, Mokeev VI, Moran P, Munoz Camacho C, Neupane K, Nguyen D, Niccolai S, Niculescu G, Osipenko M, Ostrovidov AI, Pandey P, Paolone M, Pappalardo LL, Paremuzyan R, Pasyuk E, Phelps W, Pilleux N, Pocanic D, Pogorelko O, Pokhrel M, Poudel J, Price JW, Prok Y, Raue BA, Reed T, Ripani M, Rosner G, Sabatié F, Salgado C, Schmidt A, Schumacher RA, Sharabian YG, Shirokov EV, Shrestha U, Simmerling P, Sokhan D, Sparveris N, Stepanyan S, Strakovsky II, Strauch S, Tan JA, Tyson R, Ungaro M, Vallarino S, Venturelli L, Voskanyan H, Voutier E, Wei X, Wishart R, Wood MH, Zachariou N, Zhao ZW, Ziegler V, and Zurek M
- Abstract
We present the first measurement of dihadron angular correlations in electron-nucleus scattering. The data were taken with the CLAS detector and a 5.0 GeV electron beam incident on deuterium, carbon, iron, and lead targets. Relative to deuterium, the nuclear yields of charged-pion pairs show a strong suppression for azimuthally opposite pairs, no suppression for azimuthally nearby pairs, and an enhancement of pairs with large invariant mass. These effects grow with increased nuclear size. The data are qualitatively described by the gibuu model, which suggests that hadrons form near the nuclear surface and undergo multiple scattering in nuclei.These results show that angular correlation studies can open a new way to elucidate how hadrons form and interact inside nuclei.
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- 2022
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9. Measurement of Compton Scattering at MAMI for the Extraction of the Electric and Magnetic Polarizabilities of the Proton.
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Mornacchi E, Martel PP, Abt S, Achenbach P, Adlarson P, Afzal F, Ahmed Z, Annand JRM, Arends HJ, Bashkanov M, Beck R, Biroth M, Borisov N, Braghieri A, Briscoe WJ, Cividini F, Collicott C, Costanza S, Denig A, Dolzhikov AS, Downie EJ, Drexler P, Fegan S, Gardner S, Ghosal D, Glazier DI, Gorodnov I, Gradl W, Günther M, Gurevich D, Heijkenskjöld L, Hornidge D, Huber GM, Käser A, Kashevarov VL, Kay SJD, Korolija M, Krusche B, Lazarev A, Livingston K, Lutterer S, MacGregor IJD, Manley DM, Miskimen R, Mocanu M, Mullen C, Neganov A, Neiser A, Ostrick M, Paudyal D, Pedroni P, Powell A, Rostomyan T, Sokhoyan V, Spieker K, Steffen O, Strakovsky I, Strub T, Thiel M, Thomas A, Usov YA, Wagner S, Watts DP, Werthmüller D, Wettig J, Wolfes M, and Zachariou N
- Abstract
A precise measurement of the differential cross sections dσ/dΩ and the linearly polarized photon beam asymmetry Σ_{3} for Compton scattering on the proton below pion threshold has been performed with a tagged photon beam and almost 4π detector at the Mainz Microtron. The incident photons were produced by the recently upgraded Glasgow-Mainz photon tagging facility and impinged on a cryogenic liquid hydrogen target, with the scattered photons detected in the Crystal Ball/TAPS setup. Using the highest statistics Compton scattering data ever measured on the proton along with two effective field theories (both covariant baryon and heavy-baryon) and one fixed-t dispersion relation model, constraining the fits with the Baldin sum rule, we have obtained the proton electric and magnetic polarizabilities with unprecedented precision: α_{E1}=10.99±0.16±0.47±0.17±0.34, β_{M1}=3.14±0.21±0.24±0.20±0.35; in units of 10^{-4} fm^{3} where the errors are statistical, systematic, spin polarizability dependent, and model dependent.
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- 2022
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10. Time-resolved hadronic particle acceleration in the recurrent nova RS Ophiuchi.
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Aharonian F, Ait Benkhali F, Angüner EO, Ashkar H, Backes M, Baghmanyan V, Barbosa Martins V, Batzofin R, Becherini Y, Berge D, Bernlöhr K, Bi B, Böttcher M, Boisson C, Bolmont J, de Bony de Lavergne M, Breuhaus M, Brose R, Brun F, Caroff S, Casanova S, Cerruti M, Chand T, Chen A, Cotter G, Damascene Mbarubucyeye J, Djannati-Ataï A, Dmytriiev A, Doroshenko V, Duffy C, Egberts K, Ernenwein JP, Fegan S, Feijen K, Fiasson A, Fichet de Clairfontaine G, Fontaine G, Füßling M, Funk S, Gabici S, Gallant YA, Ghafourizadeh S, Giavitto G, Giunti L, Glawion D, Glicenstein JF, Grondin MH, Hermann G, Hinton JA, Hörbe M, Hofmann W, Hoischen C, Holch TL, Holler M, Horns D, Huang Z, Jamrozy M, Jankowsky F, Jung-Richardt I, Kasai E, Katarzyński K, Katz U, Khangulyan D, Khélifi B, Klepser S, Kluźniak W, Komin N, Konno R, Kosack K, Kostunin D, Le Stum S, Lemière A, Lemoine-Goumard M, Lenain JP, Leuschner F, Lohse T, Luashvili A, Lypova I, Mackey J, Malyshev D, Malyshev D, Marandon V, Marchegiani P, Marcowith A, Martí-Devesa G, Marx R, Maurin G, Meyer M, Mitchell A, Moderski R, Mohrmann L, Montanari A, Moulin E, Muller J, Murach T, Nakashima K, de Naurois M, Nayerhoda A, Niemiec J, Priyana Noel A, O'Brien P, Ohm S, Olivera-Nieto L, de Ona Wilhelmi E, Ostrowski M, Panny S, Panter M, Parsons RD, Peron G, Pita S, Poireau V, Prokhorov DA, Prokoph H, Pühlhofer G, Punch M, Quirrenbach A, Reichherzer P, Reimer A, Reimer O, Renaud M, Reville B, Rieger F, Rowell G, Rudak B, Rueda Ricarte H, Ruiz-Velasco E, Sahakian V, Sailer S, Salzmann H, Sanchez DA, Santangelo A, Sasaki M, Schäfer J, Schüssler F, Schutte HM, Schwanke U, Senniappan M, Shapopi JNS, Simoni R, Sinha A, Sol H, Specovius A, Spencer S, Stawarz Ł, Steinmassl S, Steppa C, Takahashi T, Tanaka T, Taylor AM, Terrier R, Thorpe-Morgan C, Tsirou M, Tsuji N, Tuffs R, Uchiyama Y, Unbehaun T, van Eldik C, van Soelen B, Veh J, Venter C, Vink J, Wagner SJ, Werner F, White R, Wierzcholska A, Wong YW, Yusafzai A, Zacharias M, Zargaryan D, Zdziarski AA, Zech A, Zhu SJ, Zouari S, and Żywucka N
- Abstract
Recurrent novae are repeating thermonuclear explosions in the outer layers of white dwarfs, due to the accretion of fresh material from a binary companion. The shock generated when ejected material slams into the companion star's wind can accelerate particles. We report very-high-energy (VHE; [Formula: see text]) gamma rays from the recurrent nova RS Ophiuchi, up to 1 month after its 2021 outburst, observed using the High Energy Stereoscopic System (H.E.S.S.). The temporal profile of VHE emission is similar to that of lower-energy giga-electron volt emission, indicating a common origin, with a 2-day delay in peak flux. These observations constrain models of time-dependent particle energization, favoring a hadronic emission scenario over the leptonic alternative. Shocks in dense winds provide favorable environments for efficient acceleration of cosmic rays to very high energies.
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- 2022
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11. Multidimensional, High Precision Measurements of Beam Single Spin Asymmetries in Semi-inclusive π^{+} Electroproduction off Protons in the Valence Region.
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Diehl S, Kim A, Angelini G, Joo K, Adhikari S, Amaryan M, Arratia M, Atac H, Avakian H, Ayerbe Gayoso C, Baltzell NA, Barion L, Bastami S, Battaglieri M, Bedlinskiy I, Benmokhtar F, Bianconi A, Biselli AS, Bondi M, Bossù F, Boiarinov S, Brinkmann KT, Briscoe WJ, Brooks W, Bulumulla D, Burkert VD, Carman DS, Carvajal JC, Celentano A, Chatagnon P, Chetry T, Ciullo G, Clark L, Clary BA, Cole PL, Contalbrigo M, Costantini G, Crede V, D'Angelo A, Dashyan N, De Vita R, Defurne M, Deur A, Dilks C, Djalali C, Dugger M, Dupre R, Egiyan H, Ehrhart M, El Alaoui A, El Fassi L, Elouadrhiri L, Fegan S, Filippi A, Forest T, Gavalian G, Gilfoyle GP, Girod FX, Glazier DI, Golubenko AA, Gothe RW, Gotra Y, Griffioen KA, Guidal M, Hafidi K, Hakobyan H, Hattawy M, Hauenstein F, Hayward TB, Heddle D, Hicks K, Hobart A, Holtrop M, Hyde CE, Ireland DG, Isupov EL, Jo HS, Johnston R, Joosten S, Keller D, Khachatryan M, Khanal A, Kim W, Kripko A, Kubarovsky V, Kuhn SE, Lanza L, Leali M, Lee S, Lenisa P, Livingston K, Lu Z, MacGregor IJD, Marchand D, Markov N, Marsicano L, Mascagna V, McKinnon B, Meziani ZE, Milner RG, Mineeva T, Mirazita M, Mokeev V, Moran P, Movsisyan A, Munoz Camacho C, Nadel-Turonski P, Naidoo P, Nanda S, Neupane K, Niccolai S, Niculescu G, O'Connell TR, Osipenko M, Paolone M, Pappalardo LL, Paremuzyan R, Pasyuk E, Phelps W, Pogorelko O, Prok Y, Prokudin A, Raue BA, Ripani M, Ritman J, Rizzo A, Roberts CD, Rossi P, Rowley J, Sabatié F, Salgado C, Schmidt A, Segarra EP, Sharabian YG, Shrestha U, Simmerling P, Sokhan D, Soto O, Sparveris N, Stepanyan S, Stoler P, Strakovsky II, Strauch S, Tezgin K, Thornton A, Tyler N, Tyson R, Ungaro M, Venturelli L, Voskanyan H, Vossen A, Voutier E, Watts DP, Wei K, Wei X, Xu SS, Yale B, Zachariou N, and Zhang J
- Abstract
High precision measurements of the polarized electron beam-spin asymmetry in semi-inclusive deep inelastic scattering (SIDIS) from the proton have been performed using a 10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. We report here a high precision multidimensional study of single π^{+} SIDIS data over a large kinematic range in Bjorken x, fractional energy, and transverse momentum of the hadron as well as photon virtualities Q^{2} ranging from 1-7 GeV^{2}. In particular, the structure function ratio F_{LU}^{sinϕ}/F_{UU} has been determined, where F_{LU}^{sinϕ} is a twist-3 quantity that can reveal novel aspects of emergent hadron mass and quark-gluon correlations within the nucleon. The data's impact on the evolving understanding of the underlying reaction mechanisms and their kinematic variation is explored using theoretical models for the different contributing transverse momentum dependent parton distribution functions.
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- 2022
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12. Improved Λp Elastic Scattering Cross Sections between 0.9 and 2.0 GeV/c as a Main Ingredient of the Neutron Star Equation of State.
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Rowley J, Compton N, Djalali C, Hicks K, Price J, Zachariou N, Adhikari KP, Armstrong WR, Atac H, Baashen L, Barion L, Bashkanov M, Battaglieri M, Bedlinskiy I, Benmokhtar F, Bianconi A, Biondo L, Biselli AS, Bondi M, Bossù F, Boiarinov S, Briscoe WJ, Brooks WK, Bulumulla D, Burkert VD, Carman DS, Carvajal JC, Celentano A, Chatagnon P, Chesnokov V, Chetry T, Ciullo G, Clark L, Cole PL, Contalbrigo M, Costantini G, Crede V, D'Angelo A, Dashyan N, De Vita R, Defurne M, Deur A, Diehl S, Dupré R, Egiyan H, Ehrhart M, El Alaoui A, El Fassi L, Eugenio P, Fedotov G, Fegan S, Fersch R, Filippi A, Fradi A, Gavalian G, Girod FX, Glazier DI, Golubenko A, Gothe RW, Griffioen K, Guo L, Hafidi K, Hakobyan H, Hattawy M, Hayward TB, Heddle D, Hobart A, Holtrop M, Ilieva Y, Ireland DG, Isupov EL, Jenkins D, Jo HS, Joo K, Keller D, Khanal A, Khandaker M, Kim A, Korover I, Kripko A, Kubarovsky V, Kuhn SE, Lanza L, Leali M, Lenisa P, Livingston K, MacGregor IJD, Marchand D, Markov N, Marsicano L, Mascagna V, McCracken ME, McKinnon B, McLauchlin C, Meziani ZE, Migliorati S, Mineeva T, Mirazita M, Mokeev V, Munevar E, Munoz Camacho C, Nadel-Turonski P, Neupane K, Niccolai S, Niculescu G, O'Connell TR, Osipenko M, Ostrovidov AI, Pandey P, Paolone M, Pappalardo LL, Pasyuk E, Pogorelko O, Prok Y, Reed T, Ripani M, Ritman J, Rizzo A, Rosner G, Sabatie F, Salgado C, Schmidt A, Schumacher RA, Sharabian YG, Shrestha U, Sokhan D, Soto O, Sparveris N, Strakovsky II, Strauch S, Tyson R, Ungaro M, Venturelli L, Voskanyan H, Vossen A, Voutier E, Watts DP, Wei K, Wei X, Wishart R, Wood MH, Yale B, Yurov M, Zhang J, and Zhao ZW
- Abstract
Strange matter is believed to exist in the cores of neutron stars based on simple kinematics. If this is true, then hyperon-nucleon interactions will play a significant part in the neutron star equation of state. Yet, compared to other elastic scattering processes, there is very little data on Λ-N scattering. This experiment utilized the CEBAF Large Acceptance Spectrometer (CLAS) detector to study the Λp→Λp elastic scattering cross section in the incident Λ momentum range 0.9-2.0 GeV/c. These are the first data on this reaction since the 1970s. The new cross sections have significantly better accuracy and precision than the existing world data, and the techniques developed here can also be used in future experiments.
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- 2021
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13. First Measurement of Timelike Compton Scattering.
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Chatagnon P, Niccolai S, Stepanyan S, Amaryan MJ, Angelini G, Armstrong WR, Atac H, Ayerbe Gayoso C, Baltzell NA, Barion L, Bashkanov M, Battaglieri M, Bedlinskiy I, Benmokhtar F, Bianconi A, Biondo L, Biselli AS, Bondi M, Bossù F, Boiarinov S, Briscoe WJ, Brooks WK, Bulumulla D, Burkert VD, Carman DS, Carvajal JC, Caudron M, Celentano A, Chetry T, Ciullo G, Clark L, Cole PL, Contalbrigo M, Costantini G, Crede V, D'Angelo A, Dashyan N, Defurne M, De Vita R, Deur A, Diehl S, Djalali C, Dupré R, Egiyan H, Ehrhart M, El Alaoui A, El Fassi L, Elouadrhiri L, Fegan S, Fersch R, Filippi A, Gavalian G, Ghandilyan Y, Gilfoyle GP, Girod FX, Glazier DI, Golubenko AA, Gothe RW, Gotra Y, Griffioen KA, Guidal M, Guo L, Hakobyan H, Hattawy M, Hayward TB, Heddle D, Hobart A, Holtrop M, Hyde CE, Ilieva Y, Ireland DG, Isupov EL, Jo HS, Joo K, Kabir ML, Keller D, Khachatryan G, Khanal A, Kim A, Kim W, Kripko A, Kubarovsky V, Kuhn SE, Lanza L, Leali M, Lee S, Lenisa P, Livingston K, MacGregor IJD, Marchand D, Marsicano L, Mascagna V, McKinnon B, McLauchlin C, Migliorati S, Mirazita M, Mokeev V, Montgomery RA, Munoz Camacho C, Nadel-Turonski P, Naidoo P, Neupane K, O'Connell TR, Osipenko M, Ouillon M, Pandey P, Paolone M, Pappalardo LL, Paremuzyan R, Pasyuk E, Phelps W, Pogorelko O, Poudel J, Price JW, Prok Y, Raue BA, Reed T, Ripani M, Rizzo A, Rossi P, Rowley J, Sabatié F, Schmidt A, Segarra EP, Sharabian YG, Shirokov EV, Shrestha U, Sokhan D, Soto O, Sparveris N, Strakovsky II, Strauch S, Tyler N, Tyson R, Ungaro M, Vallarino S, Venturelli L, Voskanyan H, Vossen A, Voutier E, Watts DP, Wei K, Wei X, Wishart R, Yale B, Zachariou N, Zhang J, and Zhao ZW
- Abstract
We present the first measurement of the timelike Compton scattering process, γp→p^{'}γ^{*}(γ^{*}→e^{+}e^{-}), obtained with the CLAS12 detector at Jefferson Lab. The photon beam polarization and the decay lepton angular asymmetries are reported in the range of timelike photon virtualities 2.25
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- 2021
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14. Clinicopathological Determinants of Recurrence Risk and Survival in Mucinous Ovarian Carcinoma.
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Hollis RL, Stillie LJ, Hopkins S, Bartos C, Churchman M, Rye T, Nussey F, Fegan S, Nirsimloo R, Inman GJ, Herrington CS, and Gourley C
- Abstract
Mucinous ovarian carcinoma (MOC) is a unique form of ovarian cancer. MOC typically presents at early stage but demonstrates intrinsic chemoresistance; treatment of advanced-stage and relapsed disease is therefore challenging. We harness a large retrospective MOC cohort to identify factors associated with recurrence risk and survival. A total of 151 MOC patients were included. The 5 year disease-specific survival (DSS) was 84.5%. Risk of subsequent recurrence after a disease-free period of 2 and 5 years was low (8.3% and 5.6% over the next 10 years). The majority of cases were FIGO stage I (35.6% IA, 43.0% IC). Multivariable analysis identified stage and pathological grade as independently associated with DSS ( p < 0.001 and p < 0.001). Grade 1 stage I patients represented the majority of cases (53.0%) and demonstrated exceptional survival (10 year DSS 95.3%); survival was comparable between grade I stage IA and stage IC patients, and between grade I stage IC patients who did and did not receive adjuvant chemotherapy. At 5 years following diagnosis, the proportion of grade 1, 2 and 3 patients remaining disease free was 89.5%, 74.9% and 41.7%; the corresponding proportions for FIGO stage I, II and III/IV patients were 91.1%, 76.7% and 19.8%. Median post-relapse survival was 5.0 months. Most MOC patients present with low-grade early-stage disease and are at low risk of recurrence. New treatment options are urgently needed to improve survival following relapse, which is associated with extremely poor prognosis.
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- 2021
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15. Revealing x-ray and gamma ray temporal and spectral similarities in the GRB 190829A afterglow.
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Abdalla H, Aharonian F, Ait Benkhali F, Angüner EO, Arcaro C, Armand C, Armstrong T, Ashkar H, Backes M, Baghmanyan V, Barbosa Martins V, Barnacka A, Barnard M, Becherini Y, Berge D, Bernlöhr K, Bi B, Bissaldi E, Böttcher M, Boisson C, Bolmont J, de Bony de Lavergne M, Breuhaus M, Brun F, Brun P, Bryan M, Büchele M, Bulik T, Bylund T, Caroff S, Carosi A, Casanova S, Chand T, Chandra S, Chen A, Cotter G, Curyło M, Damascene Mbarubucyeye J, Davids ID, Davies J, Deil C, Devin J, Dirson L, Djannati-Ataï A, Dmytriiev A, Donath A, Doroshenko V, Dreyer L, Duffy C, Dyks J, Egberts K, Eichhorn F, Einecke S, Emery G, Ernenwein JP, Feijen K, Fegan S, Fiasson A, Fichet de Clairfontaine G, Fontaine G, Funk S, Füßling M, Gabici S, Gallant YA, Giavitto G, Giunti L, Glawion D, Glicenstein JF, Grondin MH, Hahn J, Haupt M, Hermann G, Hinton JA, Hofmann W, Hoischen C, Holch TL, Holler M, Hörbe M, Horns D, Huber D, Jamrozy M, Jankowsky D, Jankowsky F, Jardin-Blicq A, Joshi V, Jung-Richardt I, Kasai E, Kastendieck MA, Katarzyński K, Katz U, Khangulyan D, Khélifi B, Klepser S, Kluźniak W, Komin N, Konno R, Kosack K, Kostunin D, Kreter M, Lamanna G, Lemière A, Lemoine-Goumard M, Lenain JP, Leuschner F, Levy C, Lohse T, Lypova I, Mackey J, Majumdar J, Malyshev D, Malyshev D, Marandon V, Marchegiani P, Marcowith A, Mares A, Martí-Devesa G, Marx R, Maurin G, Meintjes PJ, Meyer M, Mitchell A, Moderski R, Mohrmann L, Montanari A, Moore C, Morris P, Moulin E, Muller J, Murach T, Nakashima K, Nayerhoda A, de Naurois M, Ndiyavala H, Niemiec J, Oakes L, O'Brien P, Odaka H, Ohm S, Olivera-Nieto L, de Ona Wilhelmi E, Ostrowski M, Panny S, Panter M, Parsons RD, Peron G, Peyaud B, Piel Q, Pita S, Poireau V, Priyana Noel A, Prokhorov DA, Prokoph H, Pühlhofer G, Punch M, Quirrenbach A, Raab S, Rauth R, Reichherzer P, Reimer A, Reimer O, Remy Q, Renaud M, Rieger F, Rinchiuso L, Romoli C, Rowell G, Rudak B, Ruiz-Velasco E, Sahakian V, Sailer S, Salzmann H, Sanchez DA, Santangelo A, Sasaki M, Scalici M, Schäfer J, Schüssler F, Schutte HM, Schwanke U, Seglar-Arroyo M, Senniappan M, Seyffert AS, Shafi N, Shapopi JNS, Shiningayamwe K, Simoni R, Sinha A, Sol H, Specovius A, Spencer S, Spir-Jacob M, Stawarz Ł, Sun L, Steenkamp R, Stegmann C, Steinmassl S, Steppa C, Takahashi T, Tam T, Tavernier T, Taylor AM, Terrier R, Thiersen JHE, Tiziani D, Tluczykont M, Tomankova L, Tsirou M, Tuffs R, Uchiyama Y, van der Walt DJ, van Eldik C, van Rensburg C, van Soelen B, Vasileiadis G, Veh J, Venter C, Vincent P, Vink J, Völk HJ, Wadiasingh Z, Wagner SJ, Watson J, Werner F, White R, Wierzcholska A, Wong YW, Yusafzai A, Zacharias M, Zanin R, Zargaryan D, Zdziarski AA, Zech A, Zhu SJ, Zorn J, Zouari S, Żywucka N, Evans P, and Page K
- Abstract
Gamma-ray bursts (GRBs), which are bright flashes of gamma rays from extragalactic sources followed by fading afterglow emission, are associated with stellar core collapse events. We report the detection of very-high-energy (VHE) gamma rays from the afterglow of GRB 190829A, between 4 and 56 hours after the trigger, using the High Energy Stereoscopic System (H.E.S.S.). The low luminosity and redshift of GRB 190829A reduce both internal and external absorption, allowing determination of its intrinsic energy spectrum. Between energies of 0.18 and 3.3 tera-electron volts, this spectrum is described by a power law with photon index of 2.07 ± 0.09, similar to the x-ray spectrum. The x-ray and VHE gamma-ray light curves also show similar decay profiles. These similar characteristics in the x-ray and gamma-ray bands challenge GRB afterglow emission scenarios., (Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)
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- 2021
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16. Observation of Beam Spin Asymmetries in the Process ep→e^{'}π^{+}π^{-}X with CLAS12.
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Hayward TB, Dilks C, Vossen A, Avakian H, Adhikari S, Angelini G, Arratia M, Atac H, Ayerbe Gayoso C, Baltzell NA, Barion L, Battaglieri M, Bedlinskiy I, Benmokhtar F, Bianconi A, Biselli AS, Bondì M, Bossù F, Boiarinov S, Briscoe WJ, Brooks WK, Bulumulla D, Burkert VD, Carman DS, Carvajal JC, Celentano A, Chatagnon P, Chetry T, Ciullo G, Clary BA, Cole PL, Contalbrigo M, Costantini G, Crede V, D'Angelo A, Dashyan N, De Vita R, Defurne M, Deur A, Diehl S, Djalali C, Dupre R, Dugger M, Egiyan H, Ehrhart M, El Alaoui A, El Fassi L, Elouadrhiri L, Fegan S, Filippi A, Forest TA, Gavalian G, Gilfoyle GP, Girod FX, Glazier DI, Golubenko AA, Gothe RW, Gotra Y, Griffioen KA, Guidal M, Hafidi K, Hakobyan H, Hattawy M, Hauenstein F, Hicks K, Hobart A, Holtrop M, Ireland DG, Isupov EL, Jo HS, Joo K, Joosten S, Keller D, Khachatryan M, Khanal A, Kim A, Kim W, Kripko A, Kubarovsky V, Kuhn SE, Lanza L, Leali M, Lee S, Lenisa P, Livingston K, MacGregor IJD, Marchand D, Markov N, Marsicano L, Mascagna V, McKinnon B, Meziani ZE, Mirazita M, Mokeev V, Movsisyan A, Munoz Camacho C, Nadel-Turonski P, Naidoo P, Nanda S, Neupane K, Niccolai S, Niculescu G, O'Connell TR, Osipenko M, Paolone M, Pappalardo LL, Paremuzyan R, Pasyuk E, Phelps W, Pogorelko O, Prok Y, Raue BA, Ripani M, Ritman J, Rizzo A, Rossi P, Rowley J, Sabatié F, Salgado C, Schmidt A, Segarra EP, Sharabian YG, Shrestha U, Sokhan D, Soto O, Sparveris N, Stepanyan S, Strakovsky II, Strauch S, Thornton A, Tyler N, Tyson R, Ungaro M, Venturelli L, Voskanyan H, Voutier E, Watts DP, Wei K, Wei X, Wood MH, Yale B, Zachariou N, and Zhang J
- Abstract
The observation of beam spin asymmetries in two-pion production in semi-inclusive deep inelastic scattering off an unpolarized proton target is reported. The data presented here were taken in the fall of 2018 with the CLAS12 spectrometer using a 10.6 GeV longitudinally spin-polarized electron beam delivered by CEBAF at JLab. The measured asymmetries provide the first opportunity to extract the parton distribution function e(x), which provides information about the interaction between gluons and quarks, in a collinear framework that offers cleaner access than previous measurements. The asymmetries also constitute the first ever signal sensitive to the helicity-dependent two-pion fragmentation function G_{1}^{⊥}. A clear sign change is observed around the ρ mass that appears in model calculations and is indicative of the dependence of the produced pions on the helicity of the fragmenting quark.
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- 2021
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17. Photoproduction of the f_{2}(1270) Meson Using the CLAS Detector.
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Carver M, Celentano A, Hicks K, Marsicano L, Mathieu V, Pilloni A, Adhikari KP, Adhikari S, Amaryan MJ, Angelini G, Atac H, Baltzell NA, Barion L, Battaglieri M, Bedlinskiy I, Benmokhtar F, Bianconi A, Biselli AS, Bondi M, Bossù F, Boiarinov S, Briscoe WJ, Brooks WK, Bulumulla D, Burkert VD, Carman DS, Carvajal JC, Chatagnon P, Chetry T, Ciullo G, Clark L, Clary BA, Cole PL, Contalbrigo M, Crede V, D'Angelo A, Dashyan N, De Vita R, Defurne M, Deur A, Diehl S, Djalali C, Dugger M, Dupre R, Egiyan H, Ehrhart M, Alaoui AE, Fassi LE, Eugenio P, Fedotov G, Fegan S, Filippi A, Gavalian G, Gevorgyan N, Gilfoyle GP, Girod FX, Gothe RW, Griffioen KA, Hafidi K, Hakobyan H, Hattawy M, Hayward TB, Heddle D, Holtrop M, Huang Q, Hyde CE, Ilieva Y, Ireland DG, Isupov EL, Jenkins D, Jo HS, Joo K, Joosten S, Keller D, Khanal A, Khandaker M, Kim A, Kim CW, Klein FJ, Kripko A, Kubarovsky V, Lanza L, Leali M, Lenisa P, Livingston K, MacGregor IJD, Marchand D, Mascagna V, McCracken ME, McKinnon B, Meziani ZE, Mokeev V, Movsisyan A, Munevar E, Camacho CM, Nadel-Turonski P, Neupane K, Niccolai S, Niculescu G, Osipenko M, Ostrovidov AI, Paolone M, Pappalardo LL, Paremuzyan R, Pasyuk E, Phelps W, Pogorelko O, Prok Y, Protopopescu D, Ripani M, Ritchie BG, Ritman J, Rizzo A, Rosner G, Rowley J, Sabatié F, Salgado C, Schmidt A, Schumacher RA, Sharabian YG, Shrestha U, Sokhan D, Soto O, Sparveris N, Stepanyan S, Strakovsky II, Strauch S, Tyler N, Tyson R, Ungaro M, Venturelli L, Voskanyan H, Voutier E, Watts DP, Wei K, Wei X, Yale B, Zachariou N, Zhang J, and Zhao ZW
- Abstract
The quark structure of the f_{2}(1270) meson has, for many years, been assumed to be a pure quark-antiquark (qq[over ¯]) resonance with quantum numbers J^{PC}=2^{++}. Recently, it was proposed that the f_{2}(1270) is a molecular state made from the attractive interaction of two ρ mesons. Such a state would be expected to decay strongly to final states with charged pions due to the dominant decay ρ→π^{+}π^{-}, whereas decay to two neutral pions would likely be suppressed. Here, we measure for the first time the reaction γp→π^{0}π^{0}p, using the CEBAF Large Acceptance Spectrometer detector at Jefferson Lab for incident beam energies between 3.6 and 5.4 GeV. Differential cross sections, dσ/dt, for f_{2}(1270) photoproduction are extracted with good precision due to low backgrounds and are compared to theoretical calculations.
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- 2021
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18. Beam Spin Asymmetry in Semi-Inclusive Electroproduction of Hadron Pairs.
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Mirazita M, Avakian H, Courtoy A, Pisano S, Adhikari S, Amaryan MJ, Angelini G, Atac H, Baltzell NA, Barion L, Battaglieri M, Bedlinskiy I, Benmokhtar F, Bianconi A, Biselli AS, Bossù F, Boiarinov S, Briscoe WJ, Brooks WK, Bulumulla D, Burkert VD, Carman DS, Carvajal JC, Celentano A, Chatagnon P, Chetry T, Ciullo G, Clary B, Cole PL, Contalbrigo M, Crede V, D'Angelo A, Dashyan N, De Vita R, Defurne M, Deur A, Diehl S, Dilks C, Djalali C, Dupre R, Egiyan H, Ehrhart M, Alaoui AE, Fassi LE, Eugenio P, Fegan S, Fersch R, Filippi A, Forest TA, Ghandilyan Y, Gavalian G, Gilfoyle GP, Giovanetti KL, Girod FX, Glazier DI, Golovatch E, Gothe RW, Griffioen KA, Guidal M, Guo L, Hafidi K, Hakobyan H, Hattawy M, Hayward TB, Heddle D, Hicks K, Hobart A, Holtrop M, Huang Q, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Jenkins D, Jo HS, Joo K, Keller D, Khanal A, Khandaker M, Kim CW, Kim W, Klein FJ, Kubarovsky V, Kuhn SE, Lanza L, Leali M, Lenisa P, Livingston K, MacGregor IJD, Marchand D, Markov N, Marsicano L, Mascagna V, McKinnon B, Milner RG, Mineeva T, Mokeev V, Mullen C, Camacho CM, Neupane K, Niculescu G, O'Connell T, Osipenko M, Paolone M, Pappalardo LL, Paremuzyan R, Park K, Pasyuk E, Phelps W, Pocanic D, Pogorelko O, Poudel J, Prok Y, Raue BA, Ripani M, Ritman J, Rizzo A, Rossi P, Sabatié F, Salgado C, Schmidt A, Schumacher RA, Sharabian YG, Shrestha U, Soto O, Sparveris N, Stepanyan S, Strakovsky II, Strauch S, Tyler N, Ungaro M, Venturelli L, Voskanyan H, Vossen A, Voutier E, Watts D, Wei K, Wei X, Wood MH, Yale B, Zachariou N, Zhang J, and Zhao ZW
- Abstract
A first measurement of the longitudinal beam spin asymmetry A_{LU} in the semi-inclusive electroproduction of pairs of charged pions is reported. A_{LU} is a higher-twist observable and offers the cleanest access to the nucleon twist-3 parton distribution function e(x). Data have been collected in the Hall-B at Jefferson Lab by impinging a 5.498-GeV electron beam on a liquid-hydrogen target, and reconstructing the scattered electron and the pion pair with the CLAS detector. One-dimensional projections of the A_{LU}^{sinϕ_{R}} moments are extracted for the kinematic variables of interest in the valence quark region. The understanding of dihadron production is essential for the interpretation of observables in single-hadron production in semi-inclusive DIS, and pioneering measurements of single-spin asymmetries in dihadron production open a new avenue in studies of QCD dynamics.
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- 2021
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19. Single π 0 production off neutrons bound in deuteron with linearly polarized photons.
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Mullen C, Gardner S, Glazier DI, Kay SJD, Livingston K, Strakovsky II, Workman RL, Abt S, Achenbach P, Afzal F, Ahmed Z, Akondi CS, Annand JRM, Bashkanov M, Beck R, Biroth M, Borisov NS, Braghieri A, Briscoe WJ, Cividini F, Collicott C, Costanza S, Denig A, Dieterle M, Downie EJ, Drexler P, Fegan S, Ferretti-Bondy MI, Ghosal D, Gorodnov I, Gradl W, Günther M, Gurevic G, Heijkenskjöld L, Hornidge D, Huber GM, Jermann N, Kaeser A, Korolija M, Kashevarov VL, Krusche B, Kulikov VV, Lazarev A, Lutterer S, MacGregor IJD, Manley DM, Martel PP, Martemianov MA, Meier C, Miskimen R, Mocanu M, Mornacchi E, Neganov A, Oberle M, Ostrick M, Otte P, Paudyal D, Pedroni P, Powell A, Prakhov SN, Reicherz G, Ron G, Rostomyan T, Sfienti C, Sokhoyan V, Spieker K, Steffen O, Strub T, Supek I, Thiel A, Thiel M, Thomas A, Unverzagt M, Usov YA, Wagner S, Walford NK, Watts DP, Werthmüller D, Wettig J, Witthauer L, Wolfes M, and Zachariou N
- Abstract
The quasifree γ → d → π 0 n ( p ) photon beam asymmetry, Σ , has been measured at photon energies, E γ , from 390 to 610 MeV, corresponding to center of mass energy from 1.271 to 1.424 GeV, for the first time. The data were collected in the A2 hall of the MAMI electron beam facility with the Crystal Ball and TAPS calorimeters covering pion center-of-mass angles from 49 ∘ to 148 ∘ . In this kinematic region, polarization observables are sensitive to contributions from the Δ ( 1232 ) and N (1440) resonances. The extracted values of Σ have been compared to predictions based on partial-wave analyses (PWAs) of the existing pion photoproduction database. Our comparison includes the SAID, MAID and Bonn-Gatchina analyses; while a revised SAID fit, including the new Σ measurements, has also been performed. In addition, isospin symmetry is examined as a way to predict π 0 n photoproduction observables, based on fits to published data in the channels π 0 p , π + n and π - p ., (© The Author(s) 2021.)
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- 2021
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20. Exploring international differences in ovarian cancer treatment: a comparison of clinical practice guidelines and patterns of care.
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Norell CH, Butler J, Farrell R, Altman A, Bentley J, Cabasag CJ, Cohen PA, Fegan S, Fung-Kee-Fung M, Gourley C, Hacker NF, Hanna L, Høgdall CK, Kristensen G, Kwon J, McNally O, Nelson G, Nordin A, O'Donnell D, Schnack T, Sykes PH, Zotow E, and Harrison S
- Subjects
- Adult, Aged, Australia, Canada, Europe, Female, Health Services Accessibility, Humans, Middle Aged, New Zealand, Surveys and Questionnaires, Carcinoma, Ovarian Epithelial therapy, Gynecology methods, Medical Oncology methods, Ovarian Neoplasms therapy, Practice Guidelines as Topic
- Abstract
Introduction: The International Cancer Benchmarking Partnership demonstrated international differences in ovarian cancer survival, particularly for women aged 65-74 with advanced disease. These findings suggest differences in treatment could be contributing to survival disparities., Objective: To compare clinical practice guidelines and patterns of care across seven high-income countries., Methods: A comparison of guidelines was performed and validated by a clinical working group. To explore clinical practice, a patterns of care survey was developed. A questionnaire regarding management and potential health system-related barriers to providing treatment was emailed to gynecological specialists. Guideline and survey results were crudely compared with 3-year survival by 'distant' stage using Spearman's rho., Results: Twenty-seven guidelines were compared, and 119 clinicians completed the survey. Guideline-related measures varied between countries but did not correlate with survival internationally. Guidelines were consistent for surgical recommendations of either primary debulking surgery or neoadjuvant chemotherapy followed by interval debulking surgery with the aim of complete cytoreduction. Reported patterns of surgical care varied internationally, including for rates of primary versus interval debulking, extensive/'ultra-radical' surgery, and perceived barriers to optimal cytoreduction. Comparison showed that willingness to undertake extensive surgery correlated with survival across countries (r
s =0.94, p=0.017). For systemic/radiation therapies, guideline differences were more pronounced, particularly for bevacizumab and PARP (poly (ADP-ribose) polymerase) inhibitors. Reported health system-related barriers also varied internationally and included a lack of adequate hospital staffing and treatment monitoring via local and national audits., Discussion: Findings suggest international variations in ovarian cancer treatment. Characteristics relating to countries with higher stage-specific survival included higher reported rates of primary surgery; willingness to undertake extensive/ultra-radical procedures; greater access to high-cost drugs; and auditing., Competing Interests: Competing interests: None declared., (© IGCS and ESGO 2020. Re-use permitted under CC BY-NC. No commercial re-use. Published by BMJ.)- Published
- 2020
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21. New approaches to cancer care in a COVID-19 world.
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Butler J, Finley C, Norell CH, Harrison S, Bryant H, Achiam MP, Altman AD, Baxter N, Bentley J, Cohen PA, Chaudry MA, Dixon E, Farrell R, Fegan S, Hashmi S, Hogdall C, Jenkins JT, Kwon J, Mala T, McNally O, Merrett N, Nelson G, Nordin A, Park J, Porter G, Reynolds J, Schieman C, Schnack T, Spigelman A, Svendsen LB, Sykes P, and Thomas R
- Subjects
- COVID-19, Humans, SARS-CoV-2, Betacoronavirus, Coronavirus Infections, Pandemics, Pneumonia, Viral
- Published
- 2020
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22. Signatures of the d^{*}(2380) Hexaquark in d(γ,pn[over →]).
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Bashkanov M, Watts DP, Kay SJD, Abt S, Achenbach P, Adlarson P, Afzal F, Ahmed Z, Akondi CS, Annand JRM, Arends HJ, Beck R, Biroth M, Borisov N, Braghieri A, Briscoe WJ, Cividini F, Collicott C, Costanza S, Denig A, Downie EJ, Drexler P, Fegan S, Fix A, Gardner S, Ghosal D, Glazier DI, Gorodnov I, Gradl W, Günther M, Gurevich D, Heijkenskjöld L, Hornidge D, Huber GM, Käser A, Kashevarov VL, Korolija M, Krusche B, Lazarev A, Livingston K, Lutterer S, MacGregor IJD, Manley DM, Martel PP, Miskimen R, Mornacchi E, Mullen C, Neganov A, Neiser A, Ostrick M, Otte PB, Paudyal D, Pedroni P, Powell A, Prakhov SN, Ron G, Sarty A, Sfienti C, Sokhoyan V, Spieker K, Steffen O, Strakovsky II, Strub T, Supek I, Thiel A, Thiel M, Thomas A, Usov YA, Wagner S, Walford NK, Werthmüller D, Wettig J, Wolfes M, Zachariou N, and Zana LA
- Abstract
We report a measurement of the spin polarization of the recoiling neutron in deuterium photodisintegration, utilizing a new large acceptance polarimeter within the Crystal Ball at MAMI. The measured photon energy range of 300-700 MeV provides the first measurement of recoil neutron polarization at photon energies where the quark substructure of the deuteron plays a role, thereby providing important new constraints on photodisintegration mechanisms. A very high neutron polarization in a narrow structure centered around E_{γ}∼570 MeV is observed, which is inconsistent with current theoretical predictions employing nucleon resonance degrees of freedom. A Legendre polynomial decomposition suggests this behavior could be related to the excitation of the d^{*}(2380) hexaquark.
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- 2020
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23. A very-high-energy component deep in the γ-ray burst afterglow.
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Abdalla H, Adam R, Aharonian F, Ait Benkhali F, Angüner EO, Arakawa M, Arcaro C, Armand C, Ashkar H, Backes M, Barbosa Martins V, Barnard M, Becherini Y, Berge D, Bernlöhr K, Bissaldi E, Blackwell R, Böttcher M, Boisson C, Bolmont J, Bonnefoy S, Bregeon J, Breuhaus M, Brun F, Brun P, Bryan M, Büchele M, Bulik T, Bylund T, Capasso M, Caroff S, Carosi A, Casanova S, Cerruti M, Chand T, Chandra S, Chen A, Colafrancesco S, Curyło M, Davids ID, Deil C, Devin J, deWilt P, Dirson L, Djannati-Ataï A, Dmytriiev A, Donath A, Doroshenko V, Dyks J, Egberts K, Emery G, Ernenwein JP, Eschbach S, Feijen K, Fegan S, Fiasson A, Fontaine G, Funk S, Füßling M, Gabici S, Gallant YA, Gaté F, Giavitto G, Giunti L, Glawion D, Glicenstein JF, Gottschall D, Grondin MH, Hahn J, Haupt M, Heinzelmann G, Henri G, Hermann G, Hinton JA, Hofmann W, Hoischen C, Holch TL, Holler M, Horns D, Huber D, Iwasaki H, Jamrozy M, Jankowsky D, Jankowsky F, Jardin-Blicq A, Jung-Richardt I, Kastendieck MA, Katarzyński K, Katsuragawa M, Katz U, Khangulyan D, Khélifi B, King J, Klepser S, Kluźniak W, Komin N, Kosack K, Kostunin D, Kreter M, Lamanna G, Lemière A, Lemoine-Goumard M, Lenain JP, Leser E, Levy C, Lohse T, Lypova I, Mackey J, Majumdar J, Malyshev D, Marandon V, Marcowith A, Mares A, Mariaud C, Martí-Devesa G, Marx R, Maurin G, Meintjes PJ, Mitchell AMW, Moderski R, Mohamed M, Mohrmann L, Moore C, Moulin E, Muller J, Murach T, Nakashima S, de Naurois M, Ndiyavala H, Niederwanger F, Niemiec J, Oakes L, O'Brien P, Odaka H, Ohm S, de Ona Wilhelmi E, Ostrowski M, Oya I, Panter M, Parsons RD, Perennes C, Petrucci PO, Peyaud B, Piel Q, Pita S, Poireau V, Priyana Noel A, Prokhorov DA, Prokoph H, Pühlhofer G, Punch M, Quirrenbach A, Raab S, Rauth R, Reimer A, Reimer O, Remy Q, Renaud M, Rieger F, Rinchiuso L, Romoli C, Rowell G, Rudak B, Ruiz-Velasco E, Sahakian V, Sailer S, Saito S, Sanchez DA, Santangelo A, Sasaki M, Schlickeiser R, Schüssler F, Schulz A, Schutte HM, Schwanke U, Schwemmer S, Seglar-Arroyo M, Senniappan M, Seyffert AS, Shafi N, Shiningayamwe K, Simoni R, Sinha A, Sol H, Specovius A, Spir-Jacob M, Stawarz Ł, Steenkamp R, Stegmann C, Steppa C, Takahashi T, Tavernier T, Taylor AM, Terrier R, Tiziani D, Tluczykont M, Trichard C, Tsirou M, Tsuji N, Tuffs R, Uchiyama Y, van der Walt DJ, van Eldik C, van Rensburg C, van Soelen B, Vasileiadis G, Veh J, Venter C, Vincent P, Vink J, Völk HJ, Vuillaume T, Wadiasingh Z, Wagner SJ, White R, Wierzcholska A, Yang R, Yoneda H, Zacharias M, Zanin R, Zdziarski AA, Zech A, Ziegler A, Zorn J, Żywucka N, de Palma F, Axelsson M, and Roberts OJ
- Abstract
Gamma-ray bursts (GRBs) are brief flashes of γ-rays and are considered to be the most energetic explosive phenomena in the Universe
1 . The emission from GRBs comprises a short (typically tens of seconds) and bright prompt emission, followed by a much longer afterglow phase. During the afterglow phase, the shocked outflow-produced by the interaction between the ejected matter and the circumburst medium-slows down, and a gradual decrease in brightness is observed2 . GRBs typically emit most of their energy via γ-rays with energies in the kiloelectronvolt-to-megaelectronvolt range, but a few photons with energies of tens of gigaelectronvolts have been detected by space-based instruments3 . However, the origins of such high-energy (above one gigaelectronvolt) photons and the presence of very-high-energy (more than 100 gigaelectronvolts) emission have remained elusive4 . Here we report observations of very-high-energy emission in the bright GRB 180720B deep in the GRB afterglow-ten hours after the end of the prompt emission phase, when the X-ray flux had already decayed by four orders of magnitude. Two possible explanations exist for the observed radiation: inverse Compton emission and synchrotron emission of ultrarelativistic electrons. Our observations show that the energy fluxes in the X-ray and γ-ray range and their photon indices remain comparable to each other throughout the afterglow. This discovery places distinct constraints on the GRB environment for both emission mechanisms, with the inverse Compton explanation alleviating the particle energy requirements for the emission observed at late times. The late timing of this detection has consequences for the future observations of GRBs at the highest energies.- Published
- 2019
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24. First Measurement of Near-Threshold J/ψ Exclusive Photoproduction off the Proton.
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Ali A, Amaryan M, Anassontzis EG, Austregesilo A, Baalouch M, Barbosa F, Barlow J, Barnes A, Barriga E, Beattie TD, Berdnikov VV, Black T, Boeglin W, Boer M, Briscoe WJ, Britton T, Brooks WK, Cannon BE, Cao N, Chudakov E, Cole S, Cortes O, Crede V, Dalton MM, Daniels T, Deur A, Dobbs S, Dolgolenko A, Dotel R, Dugger M, Dzhygadlo R, Egiyan H, Ernst A, Eugenio P, Fanelli C, Fegan S, Foda AM, Foote J, Frye J, Furletov S, Gan L, Gasparian A, Gauzshtein V, Gevorgyan N, Gleason C, Goetzen K, Goncalves A, Goryachev VS, Guo L, Hakobyan H, Hamdi A, Han S, Hardin J, Huber GM, Hurley A, Ireland DG, Ito MM, Jarvis NS, Jones RT, Kakoyan V, Kalicy G, Kamel M, Kourkoumelis C, Kuleshov S, Kuznetsov I, Larin I, Lawrence D, Lersch DI, Li H, Li W, Liu B, Livingston K, Lolos GJ, Lyubovitskij V, Mack D, Marukyan H, Matveev V, McCaughan M, McCracken M, McGinley W, McIntyre J, Meyer CA, Miskimen R, Mitchell RE, Mokaya F, Nerling F, Ng L, Ostrovidov AI, Papandreou Z, Patsyuk M, Pauli P, Pedroni R, Pentchev L, Peters KJ, Phelps W, Pooser E, Qin N, Reinhold J, Ritchie BG, Robison L, Romanov D, Romero C, Salgado C, Schertz AM, Schumacher RA, Schwiening J, Seth KK, Shen X, Shepherd MR, Smith ES, Sober DI, Somov A, Somov S, Soto O, Stevens JR, Strakovsky II, Suresh K, Tarasov V, Taylor S, Teymurazyan A, Thiel A, Vasileiadis G, Werthmüller D, Whitlatch T, Wickramaarachchi N, Williams M, Xiao T, Yang Y, Zarling J, Zhang Z, Zhao G, Zhou Q, Zhou X, and Zihlmann B
- Abstract
We report on the measurement of the γp→J/ψp cross section from E_{γ}=11.8 GeV down to the threshold at 8.2 GeV using a tagged photon beam with the GlueX experiment. We find that the total cross section falls toward the threshold less steeply than expected from two-gluon exchange models. The differential cross section dσ/dt has an exponential slope of 1.67±0.39 GeV^{-2} at 10.7 GeV average energy. The LHCb pentaquark candidates P_{c}^{+} can be produced in the s channel of this reaction. We see no evidence for them and set model-dependent upper limits on their branching fractions B(P_{c}^{+}→J/ψp) and cross sections σ(γp→P_{c}^{+})×B(P_{c}^{+}→J/ψp).
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- 2019
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25. Exploring the Structure of the Bound Proton with Deeply Virtual Compton Scattering.
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Hattawy M, Baltzell NA, Dupré R, Bültmann S, De Vita R, El Alaoui A, El Fassi L, Egiyan H, Girod FX, Guidal M, Hafidi K, Jenkins D, Liuti S, Perrin Y, Stepanyan S, Torayev B, Voutier E, Adhikari S, Angelini G, Ayerbe Gayoso C, Barion L, Battaglieri M, Bedlinskiy I, Biselli AS, Bossù F, Brooks W, Cao F, Carman DS, Celentano A, Chatagnon P, Chetry T, Ciullo G, Clark L, Cole PL, Contalbrigo M, Crede V, D'Angelo A, Dashyan N, De Sanctis E, Defurne M, Deur A, Diehl S, Djalali C, Ehrhart M, Eugenio P, Fegan S, Filippi A, Forest TA, Fradi A, Garçon M, Gavalian G, Gevorgyan N, Gilfoyle GP, Giovanetti KL, Golovatch E, Gothe RW, Griffioen KA, Harrison N, Hauenstein F, Hayward TB, Heddle D, Hicks K, Holtrop M, Ilieva Y, Ireland DG, Isupov EL, Jo HS, Johnston S, Keller D, Khachatryan G, Khachatryan M, Khanal A, Khandaker M, Kim CW, Kim W, Klein FJ, Kubarovsky V, Kuhn SE, Lanza L, L Kabir M, Lenisa P, Livingston K, MacGregor IJD, Marchand D, Markov N, Mayer M, McKinnon B, Meziani ZE, Mineeva T, Mirazita M, Montgomery RA, Munoz Camacho C, Nadel-Turonski P, Niccolai S, Ostrovidov AI, Pappalardo LL, Paremuzyan R, Pasyuk E, Pogorelko O, Poudel J, Prok Y, Protopopescu D, Ripani M, Riser D, Rizzo A, Rosner G, Rossi P, Sabatié F, Salgado C, Schumacher RA, Sharabian YG, Skorodumina I, Sokhan D, Soto O, Sparveris N, Strauch S, Taiuti M, Tan JA, Tyler N, Ungaro M, Voskanyan H, Wang R, Watts DP, Wei X, Weinstein LB, Wood MH, Zachariou N, Zhang J, and Zhao ZW
- Abstract
In the past two decades, deeply virtual Compton scattering of electrons has been successfully used to advance our knowledge of the partonic structure of the free proton and investigate correlations between the transverse position and the longitudinal momentum of quarks inside the nucleon. Meanwhile, the structure of bound nucleons in nuclei has been studied in inclusive deep-inelastic lepton scattering experiments off nuclear targets, showing a significant difference in longitudinal momentum distribution of quarks inside the bound nucleon, known as the EMC effect. In this Letter, we report the first beam spin asymmetry (BSA) measurement of exclusive deeply virtual Compton scattering off a proton bound in ^{4}He. The data used here were accumulated using a 6 GeV longitudinally polarized electron beam incident on a pressurized ^{4}He gaseous target placed within the CLAS spectrometer in Hall-B at the Thomas Jefferson National Accelerator Facility. The azimuthal angle (ϕ) dependence of the BSA was studied in a wide range of virtual photon and scattered proton kinematics. The Q^{2}, x_{B}, and t dependencies of the BSA on the bound proton are compared with those on the free proton. In the whole kinematical region of our measurements, the BSA on the bound proton is smaller by 20% to 40%, indicating possible medium modification of its partonic structure.
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- 2019
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26. First Measurements of the Double-Polarization Observables F, P, and H in ω Photoproduction off Transversely Polarized Protons in the N^{*} Resonance Region.
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Roy P, Park S, Crede V, Anisovich AV, Klempt E, Nikonov VA, Sarantsev AV, Wei NC, Huang F, Nakayama K, Adhikari KP, Adhikari S, Angelini G, Avakian H, Barion L, Battaglieri M, Bedlinskiy I, Biselli AS, Boiarinov S, Briscoe WJ, Brock J, Brooks WK, Burkert VD, Cao F, Carlin C, Carman DS, Celentano A, Chatagnon P, Chetry T, Ciullo G, Cole PL, Contalbrigo M, Cortes O, D'Angelo A, Dashyan N, De Vita R, De Sanctis E, Deur A, Diehl S, Djalali C, Dugger M, Dupre R, Duran B, Egiyan H, Ehrhart M, El Alaoui A, El Fassi L, Eugenio P, Fegan S, Filippi A, Fradi A, Gilfoyle GP, Girod FX, Golovatch E, Gothe RW, Griffioen KA, Guidal M, Guo L, Hafidi K, Hanretty C, Harrison N, Hattawy M, Hayward TB, Heddle D, Hicks K, Holtrop M, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Jenkins D, Jo HS, Johnston S, Joosten S, Kabir ML, Keith CD, Keller D, Khachatryan G, Khachatryan M, Khanal A, Khandaker M, Kim A, Kim W, Klein FJ, Kubarovsky V, Kuleshov SV, Kunkel MC, Lanza L, Lenisa P, Livingston K, MacGregor IJD, Marchand D, McKinnon B, Meekins DG, Meyer CA, Mineeva T, Mokeev V, Montgomery RA, Movsisyan A, Munoz Camacho C, Nadel-Turonski P, Niccolai S, Niculescu G, Osipenko M, Ostrovidov AI, Paolone M, Pappalardo LL, Paremuzyan R, Pasyuk E, Payette D, Phelps W, Pierce J, Pogorelko O, Prok Y, Protopopescu D, Raue BA, Ripani M, Riser D, Ritchie BG, Rizzo A, Rosner G, Sabatié F, Salgado C, Schumacher RA, Seely ML, Sharabian YG, Shrestha U, Skorodumina I, Sokhan D, Soto O, Sparveris N, Strakovsky II, Strauch S, Taiuti M, Tan JA, Torayev B, Tyler N, Ungaro M, Voskanyan H, Voutier E, Walford NK, Wang R, Watts DP, Wei X, Wood MH, Zachariou N, Zhang J, and Zhao ZW
- Abstract
First measurements of double-polarization observables in ω photoproduction off the proton are presented using transverse target polarization and data from the CEBAF Large Acceptance Spectrometer (CLAS) FROST experiment at Jefferson Lab. The beam-target asymmetry F has been measured using circularly polarized, tagged photons in the energy range 1200-2700 MeV, and the beam-target asymmetries H and P have been measured using linearly polarized, tagged photons in the energy range 1200-2000 MeV. These measurements significantly increase the database on polarization observables. The results are included in two partial-wave analyses and reveal significant contributions from several nucleon (N^{*}) resonances. In particular, contributions from new N^{*} resonances listed in the Review of Particle Properties are observed, which aid in reaching the goal of mapping out the nucleon resonance spectrum.
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- 2019
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27. Measurement of the Dynamics of the Decays D_{s}^{+}→η^{(')}e^{+}ν_{e}.
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Ablikim M, Achasov MN, Ahmed S, Albrecht M, Alekseev M, Amoroso A, An FF, An Q, Bai JZ, Bai Y, Bakina O, Baldini Ferroli R, Ban Y, Begzsuren K, Bennett DW, Bennett JV, Berger N, Bertani M, Bettoni D, Bianchi F, Boger E, Boyko I, Briere RA, Cai H, Cai X, Calcaterra A, Cao GF, Cetin SA, Chai J, Chang JF, Chelkov G, Chen G, Chen HS, Chen JC, Chen ML, Chen PL, Chen SJ, Chen XR, Chen YB, Cheng W, Chu XK, Cibinetto G, Cossio F, Dai HL, Dai JP, Dbeyssi A, Dedovich D, Deng ZY, Denig A, Denysenko I, Destefanis M, De Mori F, Ding Y, Dong C, Dong J, Dong LY, Dong MY, Dou ZL, Du SX, Duan PF, Fang J, Fang SS, Fang Y, Farinelli R, Fava L, Fegan S, Feldbauer F, Felici G, Feng CQ, Fioravanti E, Fritsch M, Fu CD, Gao Q, Gao XL, Gao Y, Gao YG, Gao Z, Garillon B, Garzia I, Gilman A, Goetzen K, Gong L, Gong WX, Gradl W, Greco M, Gu LM, Gu MH, Gu YT, Guo AQ, Guo LB, Guo RP, Guo YP, Guskov A, Haddadi Z, Han S, Hao XQ, Harris FA, He KL, He XQ, Heinsius FH, Held T, Heng YK, Hou ZL, Hu HM, Hu JF, Hu T, Hu Y, Huang GS, Huang JS, Huang XT, Huang XZ, Huang ZL, Hussain T, Ikegami Andersson W, Irshad M, Ji Q, Ji QP, Ji XB, Ji XL, Jiang XS, Jiang XY, Jiao JB, Jiao Z, Jin DP, Jin S, Jin Y, Johansson T, Julin A, Kalantar-Nayestanaki N, Kang XS, Kavatsyuk M, Ke BC, Keshk IK, Khan T, Khoukaz A, Kiese P, Kiuchi R, Kliemt R, Koch L, Kolcu OB, Kopf B, Kornicer M, Kuemmel M, Kuessner M, Kupsc A, Kurth M, Kühn W, Lange JS, Larin P, Lavezzi L, Leiber S, Leithoff H, Li C, Li C, Li DM, Li F, Li FY, Li G, Li HB, Li HJ, Li JC, Li JW, Li KJ, Li K, Li K, Li L, Li PL, Li PR, Li QY, Li T, Li WD, Li WG, Li XL, Li XN, Li XQ, Li ZB, Liang H, Liang YF, Liang YT, Liao GR, Liao LZ, Libby J, Lin CX, Lin DX, Liu B, Liu BJ, Liu CX, Liu D, Liu DY, Liu FH, Liu F, Liu F, Liu HB, Liu HL, Liu HM, Liu H, Liu H, Liu JB, Liu JY, Liu KY, Liu K, Liu LD, Liu Q, Liu SB, Liu X, Liu YB, Liu ZA, Liu Z, Long YF, Lou XC, Lu HJ, Lu JG, Lu Y, Lu YP, Luo CL, Luo MX, Luo T, Luo XL, Lusso S, Lyu XR, Ma FC, Ma HL, Ma LL, Ma MM, Ma QM, Ma T, Ma XN, Ma XY, Ma YM, Maas FE, Maggiora M, Maldaner S, Malik QA, Mangoni A, Mao YJ, Mao ZP, Marcello S, Meng ZX, Messchendorp JG, Mezzadri G, Min J, Min TJ, Mitchell RE, Mo XH, Mo YJ, Morales Morales C, Muchnoi NY, Muramatsu H, Mustafa A, Nakhoul S, Nefedov Y, Nerling F, Nikolaev IB, Ning Z, Nisar S, Niu SL, Niu XY, Olsen SL, Ouyang Q, Pacetti S, Pan Y, Papenbrock M, Patteri P, Pelizaeus M, Pellegrino J, Peng HP, Peng ZY, Peters K, Pettersson J, Ping JL, Ping RG, Pitka A, Poling R, Prasad V, Qi HR, Qi M, Qi TY, Qian S, Qiao CF, Qin N, Qin XS, Qin ZH, Qiu JF, Qu SQ, Rashid KH, Redmer CF, Richter M, Ripka M, Rivetti A, Rolo M, Rong G, Rosner C, Sarantsev A, Savrié M, Schoenning K, Shan W, Shan XY, Shao M, Shen CP, Shen PX, Shen XY, Sheng HY, Shi X, Song JJ, Song WM, Song XY, Sosio S, Sowa C, Spataro S, Sun GX, Sun JF, Sun L, Sun SS, Sun XH, Sun YJ, Sun YK, Sun YZ, Sun ZJ, Sun ZT, Tan YT, Tang CJ, Tang GY, Tang X, Tiemens M, Tsednee B, Uman I, Wang B, Wang BL, Wang CW, Wang D, Wang DY, Wang D, Wang K, Wang LL, Wang LS, Wang M, Wang M, Wang P, Wang PL, Wang WP, Wang XF, Wang Y, Wang YF, Wang Z, Wang ZG, Wang ZY, Wang Z, Weber T, Wei DH, Weidenkaff P, Wen SP, Wiedner U, Wolke M, Wu LH, Wu LJ, Wu Z, Xia L, Xia X, Xia Y, Xiao D, Xiao YJ, Xiao ZJ, Xie YG, Xie YH, Xiong XA, Xiu QL, Xu GF, Xu JJ, Xu L, Xu QJ, Xu XP, Yan F, Yan L, Yan WB, Yan WC, Yan YH, Yang HJ, Yang HX, Yang L, Yang RX, Yang YH, Yang YX, Yang Y, Yang ZQ, Ye M, Ye MH, Yin JH, You ZY, Yu BX, Yu CX, Yu JS, Yu JS, Yuan CZ, Yuan Y, Yuncu A, Zafar AA, Zeng Y, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HH, Zhang HY, Zhang J, Zhang JL, Zhang JQ, Zhang JW, Zhang JY, Zhang JZ, Zhang K, Zhang L, Zhang SF, Zhang TJ, Zhang XY, Zhang Y, Zhang YH, Zhang YT, Zhang Y, Zhang Y, Zhang Y, Zhang ZH, Zhang ZP, Zhang ZY, Zhao G, Zhao JW, Zhao JY, Zhao JZ, Zhao L, Zhao L, Zhao MG, Zhao Q, Zhao SJ, Zhao TC, Zhao YB, Zhao ZG, Zhemchugov A, Zheng B, Zheng JP, Zheng WJ, Zheng YH, Zhong B, Zhou L, Zhou Q, Zhou X, Zhou XK, Zhou XR, Zhou XY, Zhou X, Zhou X, Zhu AN, Zhu J, Zhu J, Zhu K, Zhu KJ, Zhu S, Zhu SH, Zhu XL, Zhu YC, Zhu YS, Zhu ZA, Zhuang J, Zou BS, and Zou JH
- Abstract
Using e^{+}e^{-} annihilation data corresponding to an integrated luminosity of 3.19 fb^{-1} collected at a center-of-mass energy of 4.178 GeV with the BESIII detector, we measure the absolute branching fractions B_{D_{s}^{+}→ηe^{+}ν_{e}}=(2.323±0.063_{stat}±0.063_{syst})% and B_{D_{s}^{+}→η^{'}e^{+}ν_{e}}=(0.824±0.073_{stat}±0.027_{syst})% via a tagged analysis technique, where one D_{s} is fully reconstructed in a hadronic mode. Combining these measurements with previous BESIII measurements of B_{D^{+}→η^{(')}e^{+}ν_{e}}, the η-η^{'} mixing angle in the quark flavor basis is determined to be ϕ_{P}=(40.1±2.1_{stat}±0.7_{syst})°. From the first measurements of the dynamics of D_{s}^{+}→η^{(')}e^{+}ν_{e} decays, the products of the hadronic form factors f_{+}^{η^{(')}}(0) and the Cabibbo-Kobayashi-Maskawa matrix element |V_{cs}| are determined with different form factor parametrizations. For the two-parameter series expansion, the results are f_{+}^{η}(0)|V_{cs}|=0.4455±0.0053_{stat}±0.0044_{syst} and f_{+}^{η^{'}}(0)|V_{cs}|=0.477±0.049_{stat}±0.011_{syst}.
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- 2019
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28. Evidence of a Resonant Structure in the e^{+}e^{-}→π^{+}D^{0}D^{*-} Cross Section between 4.05 and 4.60 GeV.
- Author
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Ablikim M, Achasov MN, Ahmed S, Albrecht M, Amoroso A, An FF, An Q, Bai Y, Bakina O, Baldini Ferroli R, Ban Y, Bennett DW, Bennett JV, Berger N, Bertani M, Bettoni D, Bian JM, Bianchi F, Boger E, Boyko I, Briere RA, Cai H, Cai X, Cakir O, Calcaterra A, Cao GF, Cetin SA, Chai J, Chang JF, Chelkov G, Chen G, Chen HS, Chen JC, Chen ML, Chen PL, Chen SJ, Chen YB, Cibinetto G, Dai HL, Dai JP, Dbeyssi A, Dedovich D, Deng ZY, Denig A, Denysenko I, Destefanis M, De Mori F, Ding Y, Dong C, Dong J, Dong LY, Dong MY, Dou ZL, Du SX, Duan PF, Fan JZ, Fang J, Fang SS, Fang X, Fang Y, Farinelli R, Fava L, Fegan S, Feldbauer F, Felici G, Feng CQ, Fritsch M, Fu CD, Gao Q, Gao XL, Gao Y, Gao YG, Gao Z, Garzia I, Goetzen K, Gong L, Gong WX, Gradl W, Greco M, Gu MH, Gu S, Gu YT, Guo AQ, Guo LB, Guo RP, Guo YP, Haddadi Z, Han S, Hao XQ, Harris FA, He KL, Heinsius FH, Held T, Heng YK, Holtmann T, Hou ZL, Hu C, Hu HM, Hu T, Hu Y, Huang GS, Huang JS, Huang XT, Huang XZ, Huang ZL, Hussain T, Ikegami Andersson W, Ji Q, Ji QP, Ji XB, Ji XL, Jiang XS, Jiang XY, Jiao JB, Jiao Z, Jin DP, Jin S, Jin Y, Johansson T, Julin A, Kalantar-Nayestanaki N, Kang XL, Kang XS, Kavatsyuk M, Ke BC, Khan T, Khoukaz A, Kiese P, Kliemt R, Koch L, Kolcu OB, Kopf B, Kornicer M, Kuemmel M, Kuessner M, Kuhlmann M, Kupsc A, Kühn W, Lange JS, Lara M, Larin P, Lavezzi L, Leiber S, Leithoff H, Leng C, Li C, Li C, Li DM, Li F, Li FY, Li G, Li HB, Li HJ, Li JC, Li KJ, Li K, Li K, Li L, Li PL, Li PR, Li QY, Li T, Li WD, Li WG, Li XL, Li XN, Li XQ, Li ZB, Liang H, Liang YF, Liang YT, Liao GR, Lin DX, Liu B, Liu BJ, Liu CX, Liu D, Liu FH, Liu F, Liu F, Liu HB, Liu HM, Liu H, Liu H, Liu JB, Liu JP, Liu JY, Liu K, Liu KY, Liu K, Liu PL, Liu Q, Liu SB, Liu X, Liu YB, Liu ZA, Liu Z, Long YF, Lou XC, Lu HJ, Lu JG, Lu Y, Lu YP, Luo CL, Luo MX, Luo XL, Lyu XR, Ma FC, Ma HL, Ma LL, Ma MM, Ma QM, Ma T, Ma XN, Ma XY, Ma YM, Maas FE, Maggiora M, Malik QA, Mao YJ, Mao ZP, Marcello S, Meng ZX, Messchendorp JG, Mezzadri G, Min J, Min TJ, Mitchell RE, Mo XH, Mo YJ, Morales Morales C, Morello G, Muchnoi NY, Muramatsu H, Mustafa A, Nefedov Y, Nerling F, Nikolaev IB, Ning Z, Nisar S, Niu SL, Niu XY, Olsen SL, Ouyang Q, Pacetti S, Pan Y, Papenbrock M, Patteri P, Pelizaeus M, Pellegrino J, Peng HP, Peters K, Pettersson J, Ping JL, Ping RG, Pitka A, Poling R, Prasad V, Qi HR, Qi M, Qian S, Qiao CF, Qin N, Qin XS, Qin ZH, Qiu JF, Rashid KH, Redmer CF, Richter M, Ripka M, Rolo M, Rong G, Rosner C, Ruan XD, Sarantsev A, Savrié M, Schnier C, Schoenning K, Shao M, Shen CP, Shen PX, Shen XY, Sheng HY, Song JJ, Song WM, Song XY, Sosio S, Sowa C, Spataro S, Sun GX, Sun JF, Sun L, Sun SS, Sun XH, Sun YJ, Sun YK, Sun YZ, Sun ZJ, Sun ZT, Tang CJ, Tang GY, Tang X, Tapan I, Tiemens M, Tsednee B, Uman I, Varner GS, Wang B, Wang BL, Wang DY, Wang D, Wang K, Wang LL, Wang LS, Wang M, Wang M, Wang P, Wang PL, Wang WP, Wang XF, Wang Y, Wang YD, Wang YF, Wang YQ, Wang Z, Wang ZG, Wang ZH, Wang ZY, Wang Z, Weber T, Wei DH, Weidenkaff P, Wen SP, Wiedner U, Wolke M, Wu LH, Wu LJ, Wu Z, Xia L, Xia X, Xia Y, Xiao D, Xiao H, Xiao YJ, Xiao ZJ, Xie YG, Xie YH, Xiong XA, Xiu QL, Xu GF, Xu JJ, Xu L, Xu QJ, Xu QN, Xu XP, Yan L, Yan WB, Yan WC, Yan WC, Yan YH, Yang HJ, Yang HX, Yang L, Yang YH, Yang YX, Yang Y, Ye M, Ye MH, Yin JH, You ZY, Yu BX, Yu CX, Yuan CZ, Yuan Y, Yuncu A, Zafar AA, Zallo A, Zeng Y, Zeng Z, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HH, Zhang HY, Zhang J, Zhang JL, Zhang JQ, Zhang JW, Zhang JY, Zhang JZ, Zhang K, Zhang L, Zhang SQ, Zhang XY, Zhang YH, Zhang YT, Zhang Y, Zhang Y, Zhang Y, Zhang ZH, Zhang ZP, Zhang ZY, Zhao G, Zhao JW, Zhao JY, Zhao JZ, Zhao L, Zhao L, Zhao MG, Zhao Q, Zhao SJ, Zhao TC, Zhao YB, Zhao ZG, Zhemchugov A, Zheng B, Zheng JP, Zheng WJ, Zheng YH, Zhong B, Zhou L, Zhou X, Zhou XK, Zhou XR, Zhou XY, Zhou YX, Zhu J, Zhu J, Zhu K, Zhu KJ, Zhu S, Zhu SH, Zhu XL, Zhu YC, Zhu YS, Zhu ZA, Zhuang J, Zou BS, and Zou JH
- Abstract
The cross section of the process e^{+}e^{-}→π^{+}D^{0}D^{*-} for center-of-mass energies from 4.05 to 4.60 GeV is measured precisely using data samples collected with the BESIII detector operating at the BEPCII storage ring. Two enhancements are clearly visible in the cross section around 4.23 and 4.40 GeV. Using several models to describe the dressed cross section yields stable parameters for the first enhancement, which has a mass of 4228.6±4.1±6.3 MeV/c^{2} and a width of 77.0±6.8±6.3 MeV, where the first uncertainties are statistical and the second ones are systematic. Our resonant mass is consistent with previous observations of the Y(4220) state and the theoretical prediction of a DD[over ¯]_{1}(2420) molecule. This result is the first observation of Y(4220) associated with an open-charm final state. Fits with three resonance functions with additional Y(4260), Y(4320), Y(4360), ψ(4415), or a new resonance do not show significant contributions from either of these resonances. The second enhancement is not from a single known resonance. It could contain contributions from ψ(4415) and other resonances, and a detailed amplitude analysis is required to better understand this enhancement.
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- 2019
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29. Determination of the Pseudoscalar Decay Constant f_{D_{s}^{+}} via D_{s}^{+}→μ^{+}ν_{μ}.
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Ablikim M, Achasov MN, Ahmed S, Albrecht M, Alekseev M, Amoroso A, An FF, An Q, Bai Y, Bakina O, Ferroli RB, Ban Y, Begzsuren K, Bennett DW, Bennett JV, Berger N, Bertani M, Bettoni D, Bianchi F, Boyko I, Briere RA, Cai H, Cai X, Cakir O, Calcaterra A, Cao GF, Cetin SA, Chai J, Chang JF, Chang WL, Chelkov G, Chen G, Chen HS, Chen JC, Chen ML, Chen PL, Chen SJ, Chen YB, Cibinetto G, Cossio F, Dai HL, Dai JP, Dbeyssi A, Dedovich D, Deng ZY, Denig A, Denysenko I, Destefanis M, De Mori F, Ding Y, Dong C, Dong J, Dong LY, Dong MY, Dou ZL, Du SX, Duan PF, Fan JZ, Fang J, Fang SS, Fang Y, Farinelli R, Fava L, Fegan S, Feldbauer F, Felici G, Feng CQ, Fritsch M, Fu CD, Fu Y, Gao Q, Gao XL, Gao Y, Gao YG, Gao Z, Garillon B, Garzia I, Gilman A, Goetzen K, Gong L, Gong WX, Gradl W, Greco M, Gu LM, Gu MH, Gu YT, Guo AQ, Guo LB, Guo RP, Guo YP, Guskov A, Haddadi Z, Han S, Hao XQ, Harris FA, He KL, Heinsius FH, Held T, Heng YK, Holtmann T, Hou ZL, Hu HM, Hu JF, Hu T, Hu Y, Huang GS, Huang JS, Huang XT, Huang XZ, Huang ZL, Hussain T, Andersson WI, Irshad M, Ji Q, Ji QP, Ji XB, Ji XL, Jiang XS, Jiang XY, Jiao JB, Jiao Z, Jin DP, Jin S, Jin Y, Johansson T, Julin A, Kalantar-Nayestanaki N, Kang XS, Kavatsyuk M, Ke BC, Khan T, Khoukaz A, Kiese P, Kliemt R, Koch L, Kolcu OB, Kopf B, Kornicer M, Kuemmel M, Kuessner M, Kupsc A, Kurth M, Kühn W, Lange JS, Lara M, Larin P, Lavezzi L, Leiber S, Leithoff H, Li C, Li C, Li DM, Li F, Li FY, Li G, Li HB, Li HJ, Li JC, Li JW, Li K, Li L, Li PL, Li PR, Li QY, Li T, Li WD, Li WG, Li XL, Li XN, Li XQ, Li ZB, Liang H, Liang YF, Liang YT, Liao GR, Liao LZ, Libby J, Lin CX, Lin DX, Liu B, Liu BJ, Liu CX, Liu D, Liu DY, Liu FH, Liu F, Liu F, Liu HB, Liu HL, Liu HM, Liu H, Liu H, Liu JB, Liu JY, Liu K, Liu KY, Liu K, Liu Q, Liu SB, Liu X, Liu YB, Liu ZA, Liu Z, Long YF, Lou XC, Lu HJ, Lu JD, Lu JG, Lu Y, Lu YP, Luo CL, Luo MX, Luo XL, Lusso S, Lyu XR, Ma FC, Ma HL, Ma LL, Ma MM, Ma QM, Ma XN, Ma XX, Ma XY, Ma YM, Maas FE, Maggiora M, Malik QA, Mangoni A, Mao YJ, Mao ZP, Marcello S, Meng ZX, Messchendorp JG, Mezzadri G, Min J, Min TJ, Mitchell RE, Mo XH, Mo YJ, Morales CM, Morello G, Muchnoi NY, Muramatsu H, Mustafa A, Nakhoul S, Nefedov Y, Nerling F, Nikolaev IB, Ning Z, Nisar S, Niu SL, Olsen SL, Ouyang Q, Pacetti S, Pan Y, Papenbrock M, Patteri P, Pelizaeus M, Pellegrino J, Peng HP, Peters K, Pettersson J, Ping JL, Ping RG, Pitka A, Poling R, Prasad V, Qi HR, Qi M, Qi TY, Qian S, Qiao CF, Qin N, Qin XS, Qin ZH, Qiu JF, Rashid KH, Redmer CF, Richter M, Ripka M, Rolo M, Rong G, Rosner C, Sarantsev A, Savrié M, Schnier C, Schoenning K, Shan W, Shan XY, Shao M, Shen CP, Shen PX, Shen XY, Sheng HY, Shi X, Song JJ, Song WM, Song XY, Sosio S, Sowa C, Spataro S, Sun GX, Sun JF, Sun L, Sun SS, Sun XH, Sun YJ, Sun YK, Sun YZ, Sun ZJ, Sun ZT, Tan YT, Tang CJ, Tang GY, Tang X, Tapan I, Tiemens M, Tsednee B, Uman I, Varner GS, Wang B, Wang BL, Wang CW, Wang DY, Wang D, Wang K, Wang LL, Wang LS, Wang M, Wang M, Wang P, Wang PL, Wang WP, Wang XF, Wang Y, Wang YF, Wang YQ, Wang Z, Wang ZG, Wang ZY, Wang Z, Weber T, Wei DH, Weidenkaff P, Wen SP, Wiedner U, Wolke M, Wu LH, Wu LJ, Wu Z, Xia L, Xia X, Xia Y, Xiao D, Xiao YJ, Xiao ZJ, Xie YG, Xie YH, Xiong XA, Xiu QL, Xu GF, Xu JJ, Xu L, Xu QJ, Xu QN, Xu XP, Yan F, Yan L, Yan WB, Yan WC, Yan YH, Yang HJ, Yang HX, Yang L, Yang SL, Yang YH, Yang YX, Yang Y, Ye M, Ye MH, Yin JH, You ZY, Yu BX, Yu CX, Yuan CZ, Yuan Y, Yuncu A, Zafar AA, Zallo A, Zeng Y, Zeng Z, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HH, Zhang HY, Zhang J, Zhang JL, Zhang JQ, Zhang JW, Zhang JY, Zhang JZ, Zhang K, Zhang L, Zhang SF, Zhang TJ, Zhang XY, Zhang Y, Zhang YH, Zhang YT, Zhang Y, Zhang Y, Zhang Y, Zhang ZH, Zhang ZP, Zhang ZY, Zhao G, Zhao JW, Zhao JY, Zhao JZ, Zhao L, Zhao L, Zhao MG, Zhao Q, Zhao SJ, Zhao TC, Zhao YB, Zhao ZG, Zhemchugov A, Zheng B, Zheng JP, Zheng WJ, Zheng YH, Zhong B, Zhou L, Zhou Q, Zhou X, Zhou XK, Zhou XR, Zhou XY, Zhu AN, Zhu J, Zhu J, Zhu K, Zhu KJ, Zhu S, Zhu SH, Zhu XL, Zhu YC, Zhu YS, Zhu ZA, Zhuang J, Zou BS, and Zou JH
- Abstract
Using a 3.19 fb^{-1} data sample collected at an e^{+}e^{-} center-of-mass energy of E_{cm}=4.178 GeV with the BESIII detector, we measure the branching fraction of the leptonic decay D_{s}^{+}→μ^{+}ν_{μ} to be B_{D_{s}^{+}→μ^{+}ν_{μ}}=(5.49±0.16_{stat}±0.15_{syst})×10^{-3}. Combining our branching fraction with the masses of the D_{s}^{+} and μ^{+} and the lifetime of the D_{s}^{+}, we determine f_{D_{s}^{+}}|V_{cs}|=246.2±3.6_{stat}±3.5_{syst} MeV. Using the c→s quark mixing matrix element |V_{cs}| determined from a global standard model fit, we evaluate the D_{s}^{+} decay constant f_{D_{s}^{+}}=252.9±3.7_{stat}±3.6_{syst} MeV. Alternatively, using the value of f_{D_{s}^{+}} calculated by lattice quantum chromodynamics, we find |V_{cs}|=0.985±0.014_{stat}±0.014_{syst}. These values of B_{D_{s}^{+}→μ^{+}ν_{μ}}, f_{D_{s}^{+}}|V_{cs}|, f_{D_{s}^{+}} and |V_{cs}| are each the most precise results to date.
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- 2019
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30. First Measurement of the Form Factors in D_{s}^{+}→K^{0}e^{+}ν_{e} and D_{s}^{+}→K^{*0}e^{+}ν_{e} Decays.
- Author
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Ablikim M, Achasov MN, Ahmed S, Albrecht M, Alekseev M, Amoroso A, An FF, An Q, Bai Y, Bakina O, Baldini Ferroli R, Ban Y, Begzsuren K, Bennett DW, Bennett JV, Berger N, Bertani M, Bettoni D, Bianchi F, Boger E, Boyko I, Briere RA, Cai H, Cai X, Calcaterra A, Cao GF, Cetin SA, Chai J, Chang JF, Chang WL, Chelkov G, Chen G, Chen HS, Chen JC, Chen ML, Chen PL, Chen SJ, Chen XR, Chen YB, Cheng W, Chu XK, Cibinetto G, Cossio F, Dai HL, Dai JP, Dbeyssi A, Dedovich D, Deng ZY, Denig A, Denysenko I, Destefanis M, De Mori F, Ding Y, Dong C, Dong J, Dong LY, Dong MY, Dou ZL, Du SX, Duan PF, Fang J, Fang SS, Fang Y, Farinelli R, Fava L, Fegan S, Feldbauer F, Felici G, Feng CQ, Fioravanti E, Fritsch M, Fu CD, Gao Q, Gao XL, Gao Y, Gao YG, Gao Z, Garillon B, Garzia I, Gilman A, Goetzen K, Gong L, Gong WX, Gradl W, Greco M, Gu LM, Gu MH, Gu YT, Guo AQ, Guo LB, Guo RP, Guo YP, Guskov A, Haddadi Z, Han S, Hao XQ, Harris FA, He KL, He XQ, Heinsius FH, Held T, Heng YK, Hou ZL, Hu HM, Hu JF, Hu T, Hu Y, Huang GS, Huang JS, Huang XT, Huang XZ, Huang ZL, Hussain T, Ikegami Andersson W, Irshad M, Ji Q, Ji QP, Ji XB, Ji XL, Jiang XS, Jiang XY, Jiao JB, Jiao Z, Jin DP, Jin S, Jin Y, Johansson T, Julin A, Kalantar-Nayestanaki N, Kang XS, Kavatsyuk M, Ke BC, Keshk IK, Khan T, Khoukaz A, Kiese P, Kiuchi R, Kliemt R, Koch L, Kolcu OB, Kopf B, Kornicer M, Kuemmel M, Kuessner M, Kupsc A, Kurth M, Kühn W, Lange JS, Larin P, Lavezzi L, Leiber S, Leithoff H, Li C, Li C, Li DM, Li F, Li FY, Li G, Li HB, Li HJ, Li JC, Li JW, Li KJ, Li K, Li K, Li L, Li PL, Li PR, Li QY, Li T, Li WD, Li WG, Li XL, Li XN, Li XQ, Li ZB, Liang H, Liang YF, Liang YT, Liao GR, Liao LZ, Libby J, Lin CX, Lin DX, Liu B, Liu BJ, Liu CX, Liu D, Liu DY, Liu FH, Liu F, Liu F, Liu HB, Liu HL, Liu HM, Liu H, Liu H, Liu JB, Liu JY, Liu KY, Liu K, Liu LD, Liu Q, Liu SB, Liu X, Liu YB, Liu ZA, Liu Z, Long YF, Lou XC, Lu HJ, Lu JG, Lu Y, Lu YP, Luo CL, Luo MX, Luo T, Luo XL, Lusso S, Lyu XR, Ma FC, Ma HL, Ma LL, Ma MM, Ma QM, Ma XN, Ma XY, Ma YM, Maas FE, Maggiora M, Maldaner S, Malik QA, Mangoni A, Mao YJ, Mao ZP, Marcello S, Meng ZX, Messchendorp JG, Mezzadri G, Min J, Min TJ, Mitchell RE, Mo XH, Mo YJ, Morales CM, Muchnoi NY, Muramatsu H, Mustafa A, Nakhoul S, Nefedov Y, Nerling F, Nikolaev IB, Ning Z, Nisar S, Niu SL, Niu XY, Olsen SL, Ouyang Q, Pacetti S, Pan Y, Papenbrock M, Patteri P, Pelizaeus M, Pellegrino J, Peng HP, Peng ZY, Peters K, Pettersson J, Ping JL, Ping RG, Pitka A, Poling R, Prasad V, Qi HR, Qi M, Qi TY, Qian S, Qiao CF, Qin N, Qin XS, Qin ZH, Qiu JF, Qu SQ, Rashid KH, Redmer CF, Richter M, Ripka M, Rivetti A, Rolo M, Rong G, Rosner C, Sarantsev A, Savrié M, Schoenning K, Shan W, Shan XY, Shao M, Shen CP, Shen PX, Shen XY, Sheng HY, Shi X, Song JJ, Song WM, Song XY, Sosio S, Sowa C, Spataro S, Sun GX, Sun JF, Sun L, Sun SS, Sun XH, Sun YJ, Sun YK, Sun YZ, Sun ZJ, Sun ZT, Tan YT, Tang CJ, Tang GY, Tang X, Tiemens M, Tsednee B, Uman I, Wang B, Wang BL, Wang CW, Wang D, Wang DY, Wang D, Wang K, Wang LL, Wang LS, Wang M, Wang M, Wang P, Wang PL, Wang WP, Wang XF, Wang Y, Wang YF, Wang Z, Wang ZG, Wang ZY, Wang Z, Weber T, Wei DH, Weidenkaff P, Wen SP, Wiedner U, Wolke M, Wu LH, Wu LJ, Wu Z, Xia L, Xia X, Xia Y, Xiao D, Xiao YJ, Xiao ZJ, Xie YG, Xie YH, Xiong XA, Xiu QL, Xu GF, Xu JJ, Xu L, Xu QJ, Xu XP, Yan F, Yan L, Yan WB, Yan WC, Yan YH, Yang HJ, Yang HX, Yang L, Yang RX, Yang SL, Yang YH, Yang YX, Yang Y, Yang ZQ, Ye M, Ye MH, Yin JH, You ZY, Yu BX, Yu CX, Yu JS, Yu JS, Yuan CZ, Yuan Y, Yuncu A, Zafar AA, Zeng Y, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HH, Zhang HY, Zhang J, Zhang JL, Zhang JQ, Zhang JW, Zhang JY, Zhang JZ, Zhang K, Zhang L, Zhang SF, Zhang TJ, Zhang XY, Zhang Y, Zhang YH, Zhang YT, Zhang Y, Zhang Y, Zhang Y, Zhang ZH, Zhang ZP, Zhang ZY, Zhao G, Zhao JW, Zhao JY, Zhao JZ, Zhao L, Zhao L, Zhao MG, Zhao Q, Zhao SJ, Zhao TC, Zhao YB, Zhao ZG, Zhemchugov A, Zheng B, Zheng JP, Zheng WJ, Zheng YH, Zhong B, Zhou L, Zhou Q, Zhou X, Zhou XK, Zhou XR, Zhou XY, Zhou X, Zhou X, Zhu AN, Zhu J, Zhu J, Zhu K, Zhu KJ, Zhu S, Zhu SH, Zhu XL, Zhu YC, Zhu YS, Zhu ZA, Zhuang J, Zou BS, and Zou JH
- Abstract
We report on new measurements of Cabibbo-suppressed semileptonic D_{s}^{+} decays using 3.19 fb^{-1} of e^{+}e^{-} annihilation data sample collected at a center-of-mass energy of 4.178 GeV with the BESIII detector at the BEPCII collider. Our results include branching fractions B(D_{s}^{+}→K^{0}e^{+}ν_{e})=[3.25±0.38(stat)±0.16(syst)]×10^{-3} and B(D_{s}^{+}→K^{*0}e^{+}ν_{e})=[2.37±0.26(stat)±0.20(syst)]×10^{-3}, which are much improved relative to previous measurements, and the first measurements of the hadronic form-factor parameters for these decays. For D_{s}^{+}→K^{0}e^{+}ν_{e}, we obtain f_{+}(0)=0.720±0.084(stat)±0.013(syst), and for D_{s}^{+}→K^{*0}e^{+}ν_{e}, we find form-factor ratios r_{V}=V(0)/A_{1}(0)=1.67±0.34(stat)±0.16(syst) and r_{2}=A_{2}(0)/A_{1}(0)=0.77±0.28(stat)±0.07(syst).
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- 2019
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31. Observation of D^{+}→f_{0}(500)e^{+}ν_{e} and Improved Measurements of D→ρe^{+}ν_{e}.
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Ablikim M, Achasov MN, Ahmed S, Albrecht M, Alekseev M, Amoroso A, An FF, An Q, Bai Y, Bakina O, Baldini Ferroli R, Ban Y, Begzsuren K, Bennett DW, Bennett JV, Berger N, Bertani M, Bettoni D, Bianchi F, Boger E, Boyko I, Briere RA, Cai H, Cai X, Calcaterra A, Cao GF, Cetin SA, Chai J, Chang JF, Chang WL, Chelkov G, Chen G, Chen HS, Chen JC, Chen ML, Chen PL, Chen SJ, Chen XR, Chen YB, Cheng W, Chu XK, Cibinetto G, Cossio F, Dai HL, Dai JP, Dbeyssi A, Dedovich D, Deng ZY, Denig A, Denysenko I, Destefanis M, De Mori F, Ding Y, Dong C, Dong J, Dong LY, Dong MY, Dou ZL, Du SX, Duan PF, Fang J, Fang SS, Fang Y, Farinelli R, Fava L, Fegan S, Feldbauer F, Felici G, Feng CQ, Fioravanti E, Fritsch M, Fu CD, Gao Q, Gao XL, Gao Y, Gao YG, Gao Z, Garillon B, Garzia I, Gilman A, Goetzen K, Gong L, Gong WX, Gradl W, Greco M, Gu LM, Gu MH, Gu YT, Guo AQ, Guo LB, Guo RP, Guo YP, Guskov A, Haddadi Z, Han S, Hao XQ, Harris FA, He KL, He XQ, Heinsius FH, Held T, Heng YK, Hou ZL, Hu HM, Hu JF, Hu T, Hu Y, Huang GS, Huang JS, Huang XT, Huang XZ, Huang ZL, Hussain T, Ikegami Andersson W, Irshad M, Ji Q, Ji QP, Ji XB, Ji XL, Jiang HL, Jiang XS, Jiang XY, Jiao JB, Jiao Z, Jin DP, Jin S, Jin Y, Johansson T, Julin A, Kalantar-Nayestanaki N, Kang XS, Kavatsyuk M, Ke BC, Keshk IK, Khan T, Khoukaz A, Kiese P, Kiuchi R, Kliemt R, Koch L, Kolcu OB, Kopf B, Kornicer M, Kuemmel M, Kuessner M, Kupsc A, Kurth M, Kühn W, Lange JS, Larin P, Lavezzi L, Leiber S, Leithoff H, Li C, Li C, Li DM, Li F, Li FY, Li G, Li HB, Li HJ, Li JC, Li JW, Li KJ, Li K, Li K, Li L, Li PL, Li PR, Li QY, Li T, Li WD, Li WG, Li XL, Li XN, Li XQ, Li ZB, Liang H, Liang YF, Liang YT, Liao GR, Liao LZ, Libby J, Lin CX, Lin DX, Liu B, Liu BJ, Liu CX, Liu D, Liu DY, Liu FH, Liu F, Liu F, Liu HB, Liu HL, Liu HM, Liu H, Liu H, Liu JB, Liu JY, Liu KY, Liu K, Liu LD, Liu Q, Liu SB, Liu X, Liu YB, Liu ZA, Liu Z, Long YF, Lou XC, Lu HJ, Lu JG, Lu Y, Lu YP, Luo CL, Luo MX, Luo T, Luo XL, Lusso S, Lyu XR, Ma FC, Ma HL, Ma LL, Ma MM, Ma QM, Ma XN, Ma XY, Ma YM, Maas FE, Maggiora M, Maldaner S, Malik QA, Mangoni A, Mao YJ, Mao ZP, Marcello S, Meng ZX, Messchendorp JG, Mezzadri G, Min J, Min TJ, Mitchell RE, Mo XH, Mo YJ, Morales Morales C, Muchnoi NY, Muramatsu H, Mustafa A, Nakhoul S, Nefedov Y, Nerling F, Nikolaev IB, Ning Z, Nisar S, Niu SL, Niu XY, Olsen SL, Ouyang Q, Pacetti S, Pan Y, Papenbrock M, Patteri P, Pelizaeus M, Pellegrino J, Peng HP, Peng ZY, Peters K, Pettersson J, Ping JL, Ping RG, Pitka A, Poling R, Prasad V, Qi HR, Qi M, Qi TY, Qian S, Qiao CF, Qin N, Qin XS, Qin ZH, Qiu JF, Qu SQ, Rashid KH, Redmer CF, Richter M, Ripka M, Rivetti A, Rolo M, Rong G, Rosner C, Sarantsev A, Savrié M, Schoenning K, Shan W, Shan XY, Shao M, Shen CP, Shen PX, Shen XY, Sheng HY, Shi X, Song JJ, Song WM, Song XY, Sosio S, Sowa C, Spataro S, Sui FF, Sun GX, Sun JF, Sun L, Sun SS, Sun XH, Sun YJ, Sun YK, Sun YZ, Sun ZJ, Sun ZT, Tan YT, Tang CJ, Tang GY, Tang X, Tiemens M, Tsednee B, Uman I, Wang B, Wang BL, Wang CW, Wang D, Wang DY, Wang D, Wang HH, Wang K, Wang LL, Wang LS, Wang M, Wang M, Wang P, Wang PL, Wang WP, Wang XF, Wang Y, Wang YF, Wang Z, Wang ZG, Wang ZY, Wang Z, Weber T, Wei DH, Weidenkaff P, Wen SP, Wiedner U, Wolke M, Wu LH, Wu LJ, Wu Z, Xia L, Xia X, Xia Y, Xiao D, Xiao YJ, Xiao ZJ, Xie YG, Xie YH, Xiong XA, Xiu QL, Xu GF, Xu JJ, Xu L, Xu QJ, Xu XP, Yan F, Yan L, Yan WB, Yan WC, Yan YH, Yang HJ, Yang HX, Yang L, Yang RX, Yang SL, Yang YH, Yang YX, Yang Y, Yang ZQ, Ye M, Ye MH, Yin JH, You ZY, Yu BX, Yu CX, Yu JS, Yu JS, Yuan CZ, Yuan Y, Yuncu A, Zafar AA, Zeng Y, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HH, Zhang HY, Zhang J, Zhang JL, Zhang JQ, Zhang JW, Zhang JY, Zhang JZ, Zhang K, Zhang L, Zhang SF, Zhang TJ, Zhang XY, Zhang Y, Zhang YH, Zhang YT, Zhang Y, Zhang Y, Zhang Y, Zhang ZH, Zhang ZP, Zhang ZY, Zhao G, Zhao JW, Zhao JY, Zhao JZ, Zhao L, Zhao L, Zhao MG, Zhao Q, Zhao SJ, Zhao TC, Zhao YB, Zhao ZG, Zhemchugov A, Zheng B, Zheng JP, Zheng WJ, Zheng YH, Zhong B, Zhou L, Zhou Q, Zhou X, Zhou XK, Zhou XR, Zhou XY, Zhou X, Zhou X, Zhu AN, Zhu J, Zhu J, Zhu K, Zhu KJ, Zhu S, Zhu SH, Zhu XL, Zhu YC, Zhu YS, Zhu ZA, Zhuang J, Zou BS, and Zou JH
- Abstract
Using a data sample corresponding to an integrated luminosity of 2.93 fb^{-1} recorded by the BESIII detector at a center-of-mass energy of 3.773 GeV, we present an analysis of the decays D^{0}→π^{-}π^{0}e^{+}ν_{e} and D^{+}→π^{-}π^{+}e^{+}ν_{e}. By performing a partial wave analysis, the π^{+}π^{-} S-wave contribution to D^{+}→π^{-}π^{+}e^{+}ν_{e} is observed to be (25.7±1.6±1.1)% with a statistical significance greater than 10σ, besides the dominant P-wave contribution. This is the first observation of the S-wave contribution. We measure the branching fractions B(D^{0}→ρ^{-}e^{+}ν_{e})=(1.445±0.058±0.039)×10^{-3}, B(D^{+}→ρ^{0}e^{+}ν_{e})=(1.860±0.070±0.061)×10^{-3}, and B(D^{+}→f_{0}(500)e^{+}ν_{e},f_{0}(500)→π^{+}π^{-})=(6.30±0.43±0.32)×10^{-4}. An upper limit of B(D^{+}→f_{0}(980)e^{+}ν_{e},f_{0}(980)→π^{+}π^{-})<2.8×10^{-5} is set at the 90% confidence level. We also obtain the hadronic form factor ratios of D→ρe^{+}ν_{e} at q^{2}=0 assuming the single-pole dominance parametrization: r_{V}={[V(0)]/[A_{1}(0)]}=1.695±0.083±0.051, r_{2}={[A_{2}(0)]/[A_{1}(0)]}=0.845±0.056±0.039.
- Published
- 2019
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32. Study of the D^{0}→K^{-}μ^{+}ν_{μ} Dynamics and Test of Lepton Flavor Universality with D^{0}→K^{-}ℓ^{+}ν_{ℓ} Decays.
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Ablikim M, Achasov MN, Ahmed S, Albrecht M, Alekseev M, Amoroso A, An FF, An Q, Bai JZ, Bai Y, Bakina O, Baldini Ferroli R, Ban Y, Begzsuren K, Bennett DW, Bennett JV, Berger N, Bertani M, Bettoni D, Bianchi F, Boger E, Boyko I, Briere RA, Cai H, Cai X, Cakir O, Calcaterra A, Cao GF, Cetin SA, Chai J, Chang JF, Chelkov G, Chen G, Chen HS, Chen JC, Chen ML, Chen PL, Chen SJ, Chen XR, Chen YB, Cheng W, Chu XK, Cibinetto G, Cossio F, Dai HL, Dai JP, Dbeyssi A, Dedovich D, Deng ZY, Denig A, Denysenko I, Destefanis M, De Mori F, Ding Y, Dong C, Dong J, Dong LY, Dong MY, Dou ZL, Du SX, Duan PF, Fang J, Fang SS, Fang Y, Farinelli R, Fava L, Fegan S, Feldbauer F, Felici G, Feng CQ, Fioravanti E, Fritsch M, Fu CD, Gao Q, Gao XL, Gao Y, Gao YG, Gao Z, Garillon B, Garzia I, Gilman A, Goetzen K, Gong L, Gong WX, Gradl W, Greco M, Gu MH, Gu YT, Guo AQ, Guo RP, Guo YP, Guskov A, Haddadi Z, Han S, Hao XQ, Harris FA, He KL, He XQ, Heinsius FH, Held T, Heng YK, Holtmann T, Hou ZL, Hu HM, Hu JF, Hu T, Hu Y, Huang GS, Huang JS, Huang XT, Huang XZ, Huang ZL, Hussain T, Ikegami Andersson W, Irshad M, Ji Q, Ji QP, Ji XB, Ji XL, Jiang XS, Jiang XY, Jiao JB, Jiao Z, Jin DP, Jin S, Jin Y, Johansson T, Julin A, Kalantar-Nayestanaki N, Kang XS, Kavatsyuk M, Ke BC, Khan T, Khoukaz A, Kiese P, Kiuchi R, Kliemt R, Koch L, Kolcu OB, Kopf B, Kornicer M, Kuemmel M, Kuessner M, Kupsc A, Kurth M, Kühn W, Lange JS, Lara M, Larin P, Lavezzi L, Leithoff H, Li C, Li C, Li DM, Li F, Li FY, Li G, Li HB, Li HJ, Li JC, Li JW, Li J, Li KJ, Li K, Li K, Li L, Li PL, Li PR, Li QY, Li WD, Li WG, Li XL, Li XN, Li XQ, Li ZB, Liang H, Liang YF, Liang YT, Liao GR, Liao LZ, Libby J, Lin CX, Lin DX, Liu B, Liu BJ, Liu CX, Liu D, Liu DY, Liu FH, Liu F, Liu F, Liu HB, Liu HL, Liu HM, Liu H, Liu H, Liu JB, Liu JY, Liu K, Liu KY, Liu K, Liu LD, Liu Q, Liu SB, Liu X, Liu YB, Liu ZA, Liu Z, Long YF, Lou XC, Lu HJ, Lu JG, Lu Y, Lu YP, Luo CL, Luo MX, Luo XL, Lusso S, Lyu XR, Ma FC, Ma HL, Ma LL, Ma MM, Ma QM, Ma T, Ma XN, Ma XY, Ma YM, Maas FE, Maggiora M, Malik QA, Mangoni A, Mao YJ, Mao ZP, Marcello S, Meng ZX, Messchendorp JG, Mezzadri G, Min J, Mitchell RE, Mo XH, Mo YJ, Morales Morales C, Muchnoi NY, Muramatsu H, Mustafa A, Nefedov Y, Nerling F, Nikolaev IB, Ning Z, Nisar S, Niu SL, Niu XY, Olsen SL, Ouyang Q, Pacetti S, Pan Y, Papenbrock M, Patteri P, Pelizaeus M, Pellegrino J, Peng HP, Peng ZY, Peters K, Pettersson J, Ping JL, Ping RG, Pitka A, Poling R, Prasad V, Qi HR, Qi M, Qi TY, Qian S, Qiao CF, Qin N, Qin XS, Qin ZH, Qiu JF, Rashid KH, Redmer CF, Richter M, Ripka M, Rivetti A, Rolo M, Rong G, Rosner C, Sarantsev A, Savrié M, Schnier C, Schoenning K, Shan W, Shan XY, Shao M, Shen CP, Shen PX, Shen XY, Sheng HY, Shi X, Song JJ, Song WM, Song XY, Sosio S, Sowa C, Spataro S, Sun GX, Sun JF, Sun L, Sun SS, Sun XH, Sun YJ, Sun YK, Sun YZ, Sun ZJ, Sun ZT, Tan YT, Tang CJ, Tang GY, Tang X, Tapan I, Tiemens M, Tsednee B, Uman I, Varner GS, Wang B, Wang BL, Wang D, Wang DY, Wang D, Wang K, Wang LL, Wang LS, Wang M, Wang M, Wang P, Wang PL, Wang WP, Wang XF, Wang Y, Wang YF, Wang YQ, Wang Z, Wang ZG, Wang ZY, Wang Z, Weber T, Wei DH, Weidenkaff P, Wen SP, Wiedner U, Wolke M, Wu LH, Wu LJ, Wu Z, Xia L, Xia Y, Xiao D, Xiao YJ, Xiao ZJ, Xie YG, Xie YH, Xiong XA, Xiu QL, Xu GF, Xu JJ, Xu L, Xu QJ, Xu QN, Xu XP, Yan F, Yan L, Yan WB, Yan WC, Yan YH, Yang HJ, Yang HX, Yang L, Yang YH, Yang YX, Yang Y, Yang ZQ, Ye M, Ye MH, Yin JH, You ZY, Yu BX, Yu CX, Yu JS, Yu JS, Yuan CZ, Yuan Y, Yuncu A, Zafar AA, Zeng Y, Zeng Z, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HH, Zhang HY, Zhang J, Zhang JL, Zhang JQ, Zhang JW, Zhang JY, Zhang JZ, Zhang K, Zhang L, Zhang SF, Zhang TJ, Zhang XY, Zhang Y, Zhang YH, Zhang YT, Zhang Y, Zhang Y, Zhang Y, Zhang ZH, Zhang ZP, Zhang ZY, Zhao G, Zhao JW, Zhao JY, Zhao JZ, Zhao L, Zhao L, Zhao MG, Zhao Q, Zhao SJ, Zhao TC, Zhao YB, Zhao ZG, Zhemchugov A, Zheng B, Zheng JP, Zheng WJ, Zheng YH, Zhong B, Zhou L, Zhou Q, Zhou X, Zhou XK, Zhou XR, Zhou XY, Zhou X, Zhou X, Zhu AN, Zhu J, Zhu J, Zhu K, Zhu KJ, Zhu S, Zhu SH, Zhu XL, Zhu YC, Zhu YS, Zhu ZA, Zhuang J, Zou BS, and Zou JH
- Abstract
Using e^{+}e^{-} annihilation data of 2.93 fb^{-1} collected at center-of-mass energy sqrt[s]=3.773 GeV with the BESIII detector, we measure the absolute branching fraction of D^{0}→K^{-}μ^{+}ν_{μ} with significantly improved precision: B_{D^{0}→K^{-}μ^{+}ν_{μ}}=(3.413±0.019_{stat}±0.035_{syst})%. Combining with our previous measurement of B_{D^{0}→K^{-}e^{+}ν_{e}}, the ratio of the two branching fractions is determined to be B_{D^{0}→K^{-}μ^{+}ν_{μ}}/B_{D^{0}→K^{-}e^{+}ν_{e}}=0.974±0.007_{stat}±0.012_{syst}, which agrees with the theoretical expectation of lepton flavor universality within the uncertainty. A study of the ratio of the two branching fractions in different four-momentum transfer regions is also performed, and no evidence for lepton flavor universality violation is found with current statistics. Taking inputs from global fit in the standard model and lattice quantum chromodynamics separately, we determine f_{+}^{K}(0)=0.7327±0.0039_{stat}±0.0030_{syst} and |V_{cs}|=0.955±0.005_{stat}±0.004_{syst}±0.024_{LQCD}.
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- 2019
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33. Measurement of the Absolute Branching Fraction of the Inclusive Semileptonic Λ_{c}^{+} Decay.
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Ablikim M, Achasov MN, Ahmed S, Albrecht M, Alekseev M, Amoroso A, An FF, An Q, Bai JZ, Bai Y, Bakina O, Ferroli RB, Ban Y, Bennett DW, Bennett JV, Berger N, Bertani M, Bettoni D, Bian JM, Bianchi F, Boger E, Boyko I, Briere RA, Cai H, Cai X, Cakir O, Calcaterra A, Cao GF, Cetin SA, Chai J, Chang JF, Chelkov G, Chen G, Chen HS, Chen JC, Chen ML, Chen PL, Chen SJ, Chen XR, Chen YB, Chu XK, Cibinetto G, Dai HL, Dai JP, Dbeyssi A, Dedovich D, Deng ZY, Denig A, Denysenko I, Destefanis M, De Mori F, Ding Y, Dong C, Dong J, Dong LY, Dong MY, Dou ZL, Du SX, Duan PF, Fang J, Fang SS, Fang Y, Farinelli R, Fava L, Fegan S, Feldbauer F, Felici G, Feng CQ, Fioravanti E, Fritsch M, Fu CD, Gao Q, Gao XL, Gao Y, Gao YG, Gao Z, Garillon B, Garzia I, Goetzen K, Gong L, Gong WX, Gradl W, Greco M, Gu MH, Gu YT, Guo AQ, Guo RP, Guo YP, Haddadi Z, Han S, Hao XQ, Harris FA, He KL, He XQ, Heinsius FH, Held T, Heng YK, Holtmann T, Hou ZL, Hu HM, Hu JF, Hu T, Hu Y, Huang GS, Huang JS, Huang XT, Huang XZ, Huang ZL, Hussain T, Andersson WI, Ji Q, Ji QP, Ji XB, Ji XL, Jiang XS, Jiang XY, Jiao JB, Jiao Z, Jin DP, Jin S, Jin Y, Johansson T, Julin A, Kalantar-Nayestanaki N, Kang XL, Kang XS, Kavatsyuk M, Ke BC, Khan T, Khoukaz A, Kiese P, Kliemt R, Koch L, Kolcu OB, Kopf B, Kornicer M, Kuemmel M, Kuessner M, Kuhlmann M, Kupsc A, Kühn W, Lange JS, Lara M, Larin P, Lavezzi L, Leithoff H, Leng C, Li C, Li C, Li DM, Li F, Li FY, Li G, Li HB, Li HJ, Li JC, Li J, Li KJ, Li K, Li K, Li L, Li PL, Li PR, Li QY, Li WD, Li WG, Li XL, Li XN, Li XQ, Li ZB, Liang H, Liang YF, Liang YT, Liao GR, Lin DX, Liu B, Liu BJ, Liu CX, Liu D, Liu FH, Liu F, Liu F, Liu HB, Liu HM, Liu H, Liu H, Liu JB, Liu JY, Liu K, Liu KY, Liu K, Liu LD, Liu PL, Liu Q, Liu SB, Liu X, Liu YB, Liu ZA, Liu Z, Long YF, Lou XC, Lu HJ, Lu JG, Lu Y, Lu YP, Luo CL, Luo MX, Luo XL, Lyu XR, Ma FC, Ma HL, Ma LL, Ma MM, Ma QM, Ma T, Ma XN, Ma XY, Ma YM, Maas FE, Maggiora M, Malik QA, Mao YJ, Mao ZP, Marcello S, Meng ZX, Messchendorp JG, Mezzadri G, Min J, Min TJ, Mitchell RE, Mo XH, Mo YJ, Morales CM, Muchnoi NY, Muramatsu H, Mustafa A, Nefedov Y, Nerling F, Nikolaev IB, Ning Z, Nisar S, Niu SL, Niu XY, Olsen SL, Ouyang Q, Pacetti S, Pan Y, Papenbrock M, Patteri P, Pelizaeus M, Pellegrino J, Peng HP, Peters K, Pettersson J, Ping JL, Ping RG, Pitka A, Poling R, Prasad V, Qi HR, Qi M, Qi TY, Qian S, Qiao CF, Qin N, Qin XS, Qin ZH, Qiu JF, Rashid KH, Redmer CF, Richter M, Ripka M, Rolo M, Rong G, Rosner C, Sarantsev A, Savrié M, Schnier C, Schoenning K, Shan W, Shao M, Shen CP, Shen PX, Shen XY, Sheng HY, Shi X, Song JJ, Song WM, Song XY, Sosio S, Sowa C, Spataro S, Sun GX, Sun JF, Sun L, Sun SS, Sun XH, Sun YJ, Sun YK, Sun YZ, Sun ZJ, Sun ZT, Tang CJ, Tang GY, Tang X, Tapan I, Tiemens M, Tsednee B, Uman I, Varner GS, Wang B, Wang BL, Wang D, Wang DY, Wang D, Wang K, Wang LL, Wang LS, Wang M, Wang M, Wang P, Wang PL, Wang WP, Wang XF, Wang Y, Wang YD, Wang YF, Wang YQ, Wang Z, Wang ZG, Wang ZY, Wang Z, Weber T, Wei DH, Weidenkaff P, Wen SP, Wiedner U, Wolke M, Wu LH, Wu LJ, Wu Z, Xia L, Xia Y, Xiao D, Xiao H, Xiao YJ, Xiao ZJ, Xie YG, Xie YH, Xiong XA, Xiu QL, Xu GF, Xu JJ, Xu L, Xu QJ, Xu QN, Xu XP, Yan L, Yan WB, Yan WC, Yan YH, Yang HJ, Yang HX, Yang L, Yang YH, Yang YX, Ye M, Ye MH, Yin JH, You ZY, Yu BX, Yu CX, Yu JS, Yuan CZ, Yuan Y, Yuncu A, Zafar AA, Zeng Y, Zeng Z, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HH, Zhang HY, Zhang J, Zhang JL, Zhang JQ, Zhang JW, Zhang JY, Zhang JZ, Zhang K, Zhang L, Zhang SQ, Zhang XY, Zhang YH, Zhang YT, Zhang Y, Zhang Y, Zhang Y, Zhang ZH, Zhang ZP, Zhang ZY, Zhao G, Zhao JW, Zhao JY, Zhao JZ, Zhao L, Zhao L, Zhao MG, Zhao Q, Zhao SJ, Zhao TC, Zhao YB, Zhao ZG, Zhemchugov A, Zheng B, Zheng JP, Zheng YH, Zhong B, Zhou L, Zhou X, Zhou XK, Zhou XR, Zhou XY, Zhu J, Zhu J, Zhu K, Zhu KJ, Zhu S, Zhu SH, Zhu XL, Zhu YC, Zhu YS, Zhu ZA, Zhuang J, Zou BS, and Zou JH
- Abstract
Using a data sample of e^{+}e^{-} collisions corresponding to an integrated luminosity of 567 pb^{-1} collected at a center-of-mass energy of sqrt[s]=4.6 GeV with the BESIII detector, we measure the absolute branching fraction of the inclusive semileptonic Λ_{c}^{+} decay with a double-tag method. We obtain B(Λ_{c}^{+}→Xe^{+}ν_{e})=(3.95±0.34±0.09)%, where the first uncertainty is statistical and the second systematic. Using the known Λ_{c}^{+} lifetime and the charge-averaged semileptonic decay width of nonstrange charmed mesons (D^{0} and D^{+}), we obtain the ratio of the inclusive semileptonic decay widths Γ(Λ_{c}^{+}→Xe^{+}ν_{e})/Γ[over ¯](D→Xe^{+}ν_{e})=1.26±0.12.
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- 2018
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34. Borderline Ovarian Tumors: Fifteen Years' Experience at a Scottish Tertiary Cancer Center.
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May J, Skorupskaite K, Congiu M, Ghaoui N, Walker GA, Fegan S, Martin CW, and O'Donnell RL
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Carcinoma, Ovarian Epithelial pathology, Cohort Studies, Female, Humans, Middle Aged, Neoplasm Recurrence, Local diagnosis, Neoplasm Recurrence, Local pathology, Neoplasm Staging, Ovarian Neoplasms pathology, Retrospective Studies, Scotland, Tertiary Care Centers, Young Adult, Carcinoma, Ovarian Epithelial surgery, Ovarian Neoplasms surgery
- Abstract
Objectives: Since the recognition of borderline ovarian tumors (BOTs) in the 1970s, the management of this subset of epithelial ovarian tumors has presented a challenge to clinicians. The majority present at an early stage, but their diagnosis is often only made following surgery, hence the heterogeneity of surgical management. Borderline ovarian tumors are morphologically diverse, and their behavior is subsequently also heterogeneous. We aimed to assess recurrence rates and the rate of malignant transformation in patients diagnosed with BOT. Secondary objectives included a review of current management and assessment of tumor markers, stage, cyst dimensions, and the presence of micropapillary features as prognostic indicators of recurrence., Methods: This retrospective cohort study included all patients treated with BOT between 2000 and 2015 in the southeast region of Scotland. Clinical, surgicopathological, and follow-up data were collated. Data were analyzed with reference to recurrence and malignant transformation., Results: Two hundred seventy-five patients underwent treatment for BOT in the study period. Surgical management was highly variable. A diagnosis of recurrent/persistent BOT or ovarian malignancy following initial treatment of BOT was rare, with only 12 (4%) of 275 cases. There were 7 cases (3%) of ovarian malignancy. Advanced International Federation of Gynecology and Obstetrics stage was the most prominent prognostic factor. Elevated preoperative serum CA-125 and the presence of micropapillary features correlated with advanced stage at presentation. With a lack of clear guidance, follow-up was highly variable with a median of 43 months (0-136 months)., Conclusions: To our knowledge, this study is the largest BOT cohort in the United Kingdom. Recurrent disease is rare in optimally staged, completely resected, early-stage BOT, without high-risk features. Caution is needed in women electing not to undergo completion staging after diagnosis and in those opting for a fertility-preserving approach. Thorough informed consent and clear plans for surveillance and follow-up are needed with consideration of delayed completion surgery as appropriate.
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- 2018
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35. Measurement of the Branching Fraction For the Semileptonic Decay D^{0(+)}→π^{-(0)}μ^{+}ν_{μ} and Test of Lepton Flavor Universality.
- Author
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Ablikim M, Achasov MN, Ahmed S, Albrecht M, Amoroso A, An FF, An Q, Bai JZ, Bai Y, Bakina O, Baldini Ferroli R, Ban Y, Bennett DW, Bennett JV, Berger N, Bertani M, Bettoni D, Bian JM, Bianchi F, Boger E, Boyko I, Briere RA, Cai H, Cai X, Cakir O, Calcaterra A, Cao GF, Cetin SA, Chai J, Chang JF, Chelkov G, Chen G, Chen HS, Chen JC, Chen ML, Chen PL, Chen SJ, Chen XR, Chen YB, Chu XK, Cibinetto G, Dai HL, Dai JP, Dbeyssi A, Dedovich D, Deng ZY, Denig A, Denysenko I, Destefanis M, De Mori F, Ding Y, Dong C, Dong J, Dong LY, Dong MY, Dou ZL, Du SX, Duan PF, Fang J, Fang SS, Fang Y, Farinelli R, Fava L, Fegan S, Feldbauer F, Felici G, Feng CQ, Fioravanti E, Fritsch M, Fu CD, Gao Q, Gao XL, Gao Y, Gao YG, Gao Z, Garzia I, Goetzen K, Gong L, Gong WX, Gradl W, Greco M, Gu MH, Gu YT, Guo AQ, Guo RP, Guo YP, Haddadi Z, Han S, Hao XQ, Harris FA, He KL, He XQ, Heinsius FH, Held T, Heng YK, Holtmann T, Hou ZL, Hu HM, Hu T, Hu Y, Huang GS, Huang JS, Huang XT, Huang XZ, Huang ZL, Hussain T, Ikegami Andersson W, Ji Q, Ji QP, Ji XB, Ji XL, Jiang XS, Jiang XY, Jiao JB, Jiao Z, Jin DP, Jin S, Jin Y, Johansson T, Julin A, Kalantar-Nayestanaki N, Kang XL, Kang XS, Kavatsyuk M, Ke BC, Khan T, Khoukaz A, Kiese P, Kliemt R, Koch L, Kolcu OB, Kopf B, Kornicer M, Kuemmel M, Kuessner M, Kuhlmann M, Kupsc A, Kühn W, Lange JS, Lara M, Larin P, Lavezzi L, Leithoff H, Leng C, Li C, Li C, Li DM, Li F, Li FY, Li G, Li HB, Li HJ, Li JC, Li J, Li KJ, Li K, Li K, Li L, Li PL, Li PR, Li QY, Li WD, Li WG, Li XL, Li XN, Li XQ, Li ZB, Liang H, Liang YF, Liang YT, Liao GR, Lin DX, Liu B, Liu BJ, Liu CX, Liu D, Liu FH, Liu F, Liu F, Liu HB, Liu HM, Liu H, Liu H, Liu JB, Liu JP, Liu JY, Liu K, Liu KY, Liu K, Liu LD, Liu PL, Liu Q, Liu SB, Liu X, Liu YB, Liu ZA, Liu Z, Long YF, Lou XC, Lu HJ, Lu JG, Lu Y, Lu YP, Luo CL, Luo MX, Luo XL, Lyu XR, Ma FC, Ma HL, Ma LL, Ma MM, Ma QM, Ma T, Ma XN, Ma XY, Ma YM, Maas FE, Maggiora M, Malik QA, Mao YJ, Mao ZP, Marcello S, Meng ZX, Messchendorp JG, Mezzadri G, Min J, Min TJ, Mitchell RE, Mo XH, Mo YJ, Morales Morales C, Muchnoi NY, Muramatsu H, Musiol P, Mustafa A, Nefedov Y, Nerling F, Nikolaev IB, Ning Z, Nisar S, Niu SL, Niu XY, Olsen SL, Ouyang Q, Pacetti S, Pan Y, Papenbrock M, Patteri P, Pelizaeus M, Pellegrino J, Peng HP, Peters K, Pettersson J, Ping JL, Ping RG, Pitka A, Poling R, Prasad V, Qi HR, Qi M, Qian S, Qiao CF, Qin N, Qin XS, Qin ZH, Qiu JF, Rashid KH, Redmer CF, Richter M, Ripka M, Rolo M, Rong G, Rosner C, Sarantsev A, Savrié M, Schnier C, Schoenning K, Shan W, Shao M, Shen CP, Shen PX, Shen XY, Sheng HY, Song JJ, Song WM, Song XY, Sosio S, Sowa C, Spataro S, Sun GX, Sun JF, Sun L, Sun SS, Sun XH, Sun YJ, Sun YK, Sun YZ, Sun ZJ, Sun ZT, Tang CJ, Tang GY, Tang X, Tapan I, Tiemens M, Tsednee B, Uman I, Varner GS, Wang B, Wang BL, Wang D, Wang DY, Wang D, Wang K, Wang LL, Wang LS, Wang M, Wang M, Wang P, Wang PL, Wang WP, Wang XF, Wang Y, Wang YD, Wang YF, Wang YQ, Wang Z, Wang ZG, Wang ZY, Wang Z, Weber T, Wei DH, Weidenkaff P, Wen SP, Wiedner U, Wolke M, Wu LH, Wu LJ, Wu Z, Xia L, Xia Y, Xiao D, Xiao H, Xiao YJ, Xiao ZJ, Xie YG, Xie YH, Xiong XA, Xiu QL, Xu GF, Xu JJ, Xu L, Xu QJ, Xu QN, Xu XP, Yan L, Yan WB, Yan WC, Yan YH, Yang HJ, Yang HX, Yang L, Yang YH, Yang YX, Ye M, Ye MH, Yin JH, You ZY, Yu BX, Yu CX, Yu JS, Yuan CZ, Yuan Y, Yuncu A, Zafar AA, Zeng Y, Zeng Z, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HH, Zhang HY, Zhang J, Zhang JL, Zhang JQ, Zhang JW, Zhang JY, Zhang JZ, Zhang K, Zhang L, Zhang SQ, Zhang XY, Zhang YH, Zhang YT, Zhang Y, Zhang Y, Zhang Y, Zhang ZH, Zhang ZP, Zhang ZY, Zhao G, Zhao JW, Zhao JY, Zhao JZ, Zhao L, Zhao L, Zhao MG, Zhao Q, Zhao SJ, Zhao TC, Zhao YB, Zhao ZG, Zhemchugov A, Zheng B, Zheng JP, Zheng YH, Zhong B, Zhou L, Zhou X, Zhou XK, Zhou XR, Zhou XY, Zhou YX, Zhu J, Zhu J, Zhu K, Zhu KJ, Zhu S, Zhu SH, Zhu XL, Zhu YC, Zhu YS, Zhu ZA, Zhuang J, Zou BS, and Zou JH
- Abstract
Using a data sample corresponding to an integrated luminosity of 2.93 fb^{-1} taken at a center-of-mass energy of 3.773 GeV with the BESIII detector operated at the BEPCII collider, we perform an analysis of the semileptonic decays D^{0(+)}→π^{-(0)}μ^{+}ν_{μ}. The branching fractions of D^{0}→π^{-}μ^{+}ν_{μ} and D^{+}→π^{0}μ^{+}ν_{μ} are measured to be (0.272±0.008_{stat}±0.006_{syst})% and (0.350±0.011_{stat}±0.010_{syst})%, respectively, where the former is of much improved precision compared to previous results and the latter is determined for the first time. Using these results along with previous BESIII measurements of D^{0(+)}→π^{-(0)}e^{+}ν_{e}, we calculate the branching fraction ratios to be R^{0}≡B_{D^{0}→π^{-}μ^{+}ν_{μ}}/B_{D^{0}→π^{-}e^{+}ν_{e}}=0.922±0.030_{stat}±0.022_{syst} and R^{+}≡B_{D^{+}→π^{0}μ^{+}ν_{μ}}/B_{D^{+}→π^{0}e^{+}ν_{e}}=0.964±0.037_{stat}±0.026_{syst}, which are compatible with the theoretical expectation of lepton flavor universality within 1.7σ and 0.5σ, respectively. We also examine the branching fraction ratios in different four-momentum transfer square regions, and find no significant deviations from the standard model predictions.
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- 2018
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36. Measurement of the Absolute Branching Fraction of the Inclusive Decay Λ_{c}^{+}→Λ+X.
- Author
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Ablikim M, Achasov MN, Ahmed S, Albrecht M, Alekseev M, Amoroso A, An FF, An Q, Bai JZ, Bai Y, Bakina O, Baldini Ferroli R, Ban Y, Bennett DW, Bennett JV, Berger N, Bertani M, Bettoni D, Bian JM, Bianchi F, Boger E, Boyko I, Briere RA, Cai H, Cai X, Cakir O, Calcaterra A, Cao GF, Cetin SA, Chai J, Chang JF, Chelkov G, Chen G, Chen HS, Chen JC, Chen ML, Chen PL, Chen SJ, Chen XR, Chen YB, Chu XK, Cibinetto G, Dai HL, Dai JP, Dbeyssi A, Dedovich D, Deng ZY, Denig A, Denysenko I, Destefanis M, De Mori F, Ding Y, Dong C, Dong J, Dong LY, Dong MY, Dou ZL, Du SX, Duan PF, Fang J, Fang SS, Fang X, Fang Y, Farinelli R, Fava L, Fegan S, Feldbauer F, Felici G, Feng CQ, Fioravanti E, Fritsch M, Fu CD, Gao Q, Gao XL, Gao Y, Gao YG, Gao Z, Garillon B, Garzia I, Goetzen K, Gong L, Gong WX, Gradl W, Greco M, Gu MH, Gu S, Gu YT, Guo AQ, Guo LB, Guo RP, Guo YP, Haddadi Z, Han S, Hao XQ, Harris FA, He KL, He XQ, Heinsius FH, Held T, Heng YK, Holtmann T, Hou ZL, Hu C, Hu HM, Hu T, Hu Y, Huang GS, Huang JS, Huang XT, Huang XZ, Huang ZL, Hussain T, Ikegami Andersson W, Ji Q, Ji QP, Ji XB, Ji XL, Jiang XS, Jiang XY, Jiao JB, Jiao Z, Jin DP, Jin S, Jin Y, Johansson T, Julin A, Kalantar-Nayestanaki N, Kang XL, Kang XS, Kavatsyuk M, Ke BC, Khan T, Khoukaz A, Kiese P, Kliemt R, Koch L, Kolcu OB, Kopf B, Kornicer M, Kuemmel M, Kuessner M, Kuhlmann M, Kupsc A, Kühn W, Lange JS, Lara M, Larin P, Lavezzi L, Leiber S, Leithoff H, Leng C, Li C, Li C, Li DM, Li F, Li FY, Li G, Li HB, Li HJ, Li JC, Li KJ, Li K, Li K, Li L, Li PL, Li PR, Li QY, Li T, Li WD, Li WG, Li XL, Li XN, Li XQ, Li ZB, Liang H, Liang YF, Liang YT, Liao GR, Lin DX, Liu B, Liu BJ, Liu CX, Liu D, Liu FH, Liu F, Liu F, Liu HB, Liu HM, Liu H, Liu H, Liu JB, Liu JY, Liu K, Liu KY, Liu K, Liu LD, Liu PL, Liu Q, Liu SB, Liu X, Liu YB, Liu ZA, Liu Z, Long YF, Lou XC, Lu HJ, Lu JG, Lu Y, Lu YP, Luo CL, Luo MX, Luo XL, Lyu XR, Ma FC, Ma HL, Ma LL, Ma MM, Ma QM, Ma T, Ma XN, Ma XY, Ma YM, Maas FE, Maggiora M, Malik QA, Mao YJ, Mao ZP, Marcello S, Meng ZX, Messchendorp JG, Mezzadri G, Min J, Min TJ, Mitchell RE, Mo XH, Mo YJ, Morales Morales C, Morello G, Muchnoi NY, Muramatsu H, Mustafa A, Nefedov Y, Nerling F, Nikolaev IB, Ning Z, Nisar S, Niu SL, Niu XY, Olsen SL, Ouyang Q, Pacetti S, Pan Y, Papenbrock M, Patteri P, Pelizaeus M, Pellegrino J, Peng HP, Peters K, Pettersson J, Ping JL, Ping RG, Pitka A, Poling R, Prasad V, Qi HR, Qi M, Qi TY, Qian S, Qiao CF, Qin N, Qin XS, Qin ZH, Qiu JF, Rashid KH, Redmer CF, Richter M, Ripka M, Rolo M, Rong G, Rosner C, Ruan XD, Sarantsev A, Savrié M, Schnier C, Schoenning K, Shan W, Shao M, Shen CP, Shen PX, Shen XY, Sheng HY, Song JJ, Song WM, Song XY, Sosio S, Sowa C, Spataro S, Sun GX, Sun JF, Sun L, Sun SS, Sun XH, Sun YJ, Sun YK, Sun YZ, Sun ZJ, Sun ZT, Tang CJ, Tang GY, Tang X, Tapan I, Tiemens M, Tsednee B, Uman I, Varner GS, Wang B, Wang BL, Wang D, Wang DY, Wang D, Wang K, Wang LL, Wang LS, Wang M, Wang M, Wang P, Wang PL, Wang WP, Wang XF, Wang Y, Wang YD, Wang YF, Wang YQ, Wang Z, Wang ZG, Wang ZH, Wang ZY, Wang Z, Weber T, Wei DH, Weidenkaff P, Wen SP, Wiedner U, Wolke M, Wu LH, Wu LJ, Wu Z, Xia L, Xia X, Xia Y, Xiao D, Xiao H, Xiao YJ, Xiao ZJ, Xie YG, Xie YH, Xiong XA, Xiu QL, Xu GF, Xu JJ, Xu L, Xu QJ, Xu QN, Xu XP, Yan L, Yan WB, Yan WC, Yan WC, Yan YH, Yang HJ, Yang HX, Yang L, Yang YH, Yang YX, Yang Y, Ye M, Ye MH, Yin JH, You ZY, Yu BX, Yu CX, Yu JS, Yuan CZ, Yuan Y, Yuncu A, Zafar AA, Zallo A, Zeng Y, Zeng Z, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HH, Zhang HY, Zhang J, Zhang JL, Zhang JQ, Zhang JW, Zhang JY, Zhang JZ, Zhang K, Zhang L, Zhang SQ, Zhang XY, Zhang YH, Zhang YT, Zhang Y, Zhang Y, Zhang Y, Zhang ZH, Zhang ZP, Zhang ZY, Zhao G, Zhao JW, Zhao JY, Zhao JZ, Zhao L, Zhao L, Zhao MG, Zhao Q, Zhao SJ, Zhao TC, Zhao YB, Zhao ZG, Zhemchugov A, Zheng B, Zheng JP, Zheng WJ, Zheng YH, Zhong B, Zhou L, Zhou X, Zhou XK, Zhou XR, Zhou XY, Zhou YX, Zhu J, Zhu J, Zhu K, Zhu KJ, Zhu S, Zhu SH, Zhu XL, Zhu YC, Zhu YS, Zhu ZA, Zhuang J, Zou BS, and Zou JH
- Abstract
Based on an e^{+}e^{-} collision data sample corresponding to an integrated luminosity of 567 pb^{-1} taken at the center-of-mass energy of sqrt[s]=4.6 GeV with the BESIII detector, we measure the absolute branching fraction of the inclusive decay Λ_{c}^{+}→Λ+X to be B(Λ_{c}^{+}→Λ+X)=(38.2_{-2.2}^{+2.8}±0.9)% using the double-tag method, where X refers to any possible final state particles. In addition, we search for direct CP violation in the charge asymmetry of this inclusive decay for the first time, and obtain A_{CP}≡[B(Λ_{c}^{+}→Λ+X)-B(Λ[over ¯]_{c}^{-}→Λ[over ¯]+X)]/[B(Λ_{c}^{+}→Λ+X)+B(Λ[over ¯]_{c}^{-}→Λ[over ¯]+X)]=(2.1_{-6.6}^{+7.0}±1.6)%, a statistically limited result with no evidence of CP violation.
- Published
- 2018
- Full Text
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37. Observation of a_{0}^{0}(980)-f_{0}(980) Mixing.
- Author
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Ablikim M, Achasov MN, Ahmed S, Albrecht M, Alekseev M, Amoroso A, An FF, An Q, Bai JZ, Bai Y, Bakina O, Baldini Ferroli R, Ban Y, Bennett DW, Bennett JV, Berger N, Bertani M, Bettoni D, Bian JM, Bianchi F, Boger E, Boyko I, Briere RA, Cai H, Cai X, Cakir O, Calcaterra A, Cao GF, Cetin SA, Chai J, Chang JF, Chelkov G, Chen G, Chen HS, Chen JC, Chen ML, Chen SJ, Chen XR, Chen YB, Chu XK, Cibinetto G, Dai HL, Dai JP, Dbeyssi A, Dedovich D, Deng ZY, Denig A, Denysenko I, Destefanis M, De Mori F, Ding Y, Dong C, Dong J, Dong LY, Dong MY, Dorjkhaidav O, Dou ZL, Du SX, Duan PF, Fang J, Fang SS, Fang X, Fang Y, Farinelli R, Fava L, Fegan S, Feldbauer F, Felici G, Feng CQ, Fioravanti E, Fritsch M, Fu CD, Gao Q, Gao XL, Gao Y, Gao YG, Gao Z, Garillon B, Garzia I, Goetzen K, Gong L, Gong WX, Gradl W, Greco M, Gu MH, Gu S, Gu YT, Guo AQ, Guo LB, Guo RP, Guo YP, Haddadi Z, Han S, Hao XQ, Harris FA, He KL, He XQ, Heinsius FH, Held T, Heng YK, Holtmann T, Hou ZL, Hu C, Hu HM, Hu T, Hu Y, Huang GS, Huang JS, Huang SH, Huang XT, Huang XZ, Huang ZL, Hussain T, Ikegami Andersson W, Ji Q, Ji QP, Ji XB, Ji XL, Jiang XS, Jiang XY, Jiao JB, Jiao Z, Jin DP, Jin S, Jin Y, Johansson T, Julin A, Kalantar-Nayestanaki N, Kang XL, Kang XS, Kavatsyuk M, Ke BC, Khan T, Khoukaz A, Kiese P, Kliemt R, Koch L, Kolcu OB, Kopf B, Kornicer M, Kuemmel M, Kuhlmann M, Kupsc A, Kühn W, Lange JS, Lara M, Larin P, Lavezzi L, Leithoff H, Leng C, Li C, Li C, Li DM, Li F, Li FY, Li G, Li HB, Li HJ, Li JC, Li J, Li K, Li K, Li KJ, Li L, Li PL, Li PR, Li QY, Li T, Li WD, Li WG, Li XL, Li XN, Li XQ, Li ZB, Liang H, Liang YF, Liang YT, Liao GR, Lin DX, Liu B, Liu BJ, Liu CX, Liu D, Liu FH, Liu F, Liu F, Liu HB, Liu HH, Liu HH, Liu HM, Liu JB, Liu JY, Liu K, Liu KY, Liu K, Liu LD, Liu PL, Liu Q, Liu SB, Liu X, Liu YB, Liu ZA, Liu Z, Long YF, Lou XC, Lu HJ, Lu JG, Lu Y, Lu YP, Luo CL, Luo MX, Luo XL, Lyu XR, Ma FC, Ma HL, Ma LL, Ma MM, Ma QM, Ma T, Ma XN, Ma XY, Ma YM, Maas FE, Maggiora M, Malik QA, Mao YJ, Mao ZP, Marcello S, Meng ZX, Messchendorp JG, Mezzadri G, Min J, Min TJ, Mitchell RE, Mo XH, Mo YJ, Morales Morales C, Morello G, Muchnoi NY, Muramatsu H, Mustafa A, Nefedov Y, Nerling F, Nikolaev IB, Ning Z, Nisar S, Niu SL, Niu XY, Olsen SL, Ouyang Q, Pacetti S, Pan Y, Papenbrock M, Patteri P, Pelizaeus M, Pellegrino J, Peng HP, Peters K, Pettersson J, Ping JL, Ping RG, Pitka A, Poling R, Prasad V, Qi HR, Qi M, Qian S, Qiao CF, Qin N, Qin XS, Qin ZH, Qiu JF, Rashid KH, Redmer CF, Richter M, Ripka M, Rolo M, Rong G, Rosner C, Sarantsev A, Savrié M, Schnier C, Schoenning K, Shan W, Shao M, Shen CP, Shen PX, Shen XY, Sheng HY, Song JJ, Song WM, Song XY, Sosio S, Sowa C, Spataro S, Sun GX, Sun JF, Sun L, Sun SS, Sun XH, Sun YJ, Sun YK, Sun YZ, Sun ZJ, Sun ZT, Tang CJ, Tang GY, Tang X, Tapan I, Tiemens M, Tsednee BT, Uman I, Varner GS, Wang B, Wang BL, Wang D, Wang DY, Wang D, Wang K, Wang LL, Wang LS, Wang M, Wang P, Wang PL, Wang WP, Wang XF, Wang Y, Wang YD, Wang YF, Wang YQ, Wang Z, Wang ZG, Wang ZH, Wang ZY, Wang ZY, Weber T, Wei DH, Wei JH, Weidenkaff P, Wen SP, Wiedner U, Wolke M, Wu LH, Wu LJ, Wu Z, Xia L, Xia Y, Xiao D, Xiao H, Xiao YJ, Xiao ZJ, Xie XH, Xie YG, Xie YH, Xiong XA, Xiu QL, Xu GF, Xu JJ, Xu L, Xu QJ, Xu QN, Xu XP, Yan L, Yan WB, Yan WC, Yan YH, Yang HJ, Yang HX, Yang L, Yang YH, Yang YX, Ye M, Ye MH, Yin JH, You ZY, Yu BX, Yu CX, Yu JS, Yuan CZ, Yuan Y, Yuncu A, Zafar AA, Zeng Y, Zeng Z, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HH, Zhang HY, Zhang J, Zhang JL, Zhang JQ, Zhang JW, Zhang JY, Zhang JZ, Zhang K, Zhang L, Zhang SQ, Zhang XY, Zhang Y, Zhang Y, Zhang YH, Zhang YT, Zhang Y, Zhang ZH, Zhang ZP, Zhang ZY, Zhao G, Zhao JW, Zhao JY, Zhao JZ, Zhao L, Zhao L, Zhao MG, Zhao Q, Zhao SJ, Zhao TC, Zhao YB, Zhao ZG, Zhemchugov A, Zheng B, Zheng JP, Zheng WJ, Zheng YH, Zhong B, Zhou L, Zhou X, Zhou XK, Zhou XR, Zhou XY, Zhu J, Zhu K, Zhu KJ, Zhu S, Zhu SH, Zhu XL, Zhu YC, Zhu YS, Zhu ZA, Zhuang J, Zou BS, and Zou JH
- Abstract
We report the first observation of a_{0}^{0}(980)-f_{0}(980) mixing in the decays of J/ψ→ϕf_{0}(980)→ϕa_{0}^{0}(980)→ϕηπ^{0} and χ_{c1}→a_{0}^{0}(980)π^{0}→f_{0}(980)π^{0}→π^{+}π^{-}π^{0}, using data samples of 1.31×10^{9} J/ψ events and 4.48×10^{8} ψ(3686) events accumulated with the BESIII detector. The signals of f_{0}(980)→a_{0}^{0}(980) and a_{0}^{0}(980)→f_{0}(980) mixing are observed at levels of statistical significance of 7.4σ and 5.5σ, respectively. The corresponding branching fractions and mixing intensities are measured and the constraint regions on the coupling constants, g_{a_{0}K^{+}K^{-}} and g_{f_{0}K^{+}K^{-}}, are estimated. The results improve the understanding of the nature of a_{0}^{0}(980) and f_{0}(980).
- Published
- 2018
- Full Text
- View/download PDF
38. Precision Study of η^{'}→γπ^{+}π^{-} Decay Dynamics.
- Author
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Ablikim M, Achasov MN, Ahmed S, Ai XC, Albayrak O, Albrecht M, Ambrose DJ, Amoroso A, An FF, An Q, Bai JZ, Ferroli RB, Ban Y, Bennett DW, Bennett JV, Berger N, Bertani M, Bettoni D, Bian JM, Bianchi F, Boger E, Boyko I, Briere RA, Cai H, Cai X, Cakir O, Calcaterra A, Cao GF, Cetin SA, Chai J, Chang JF, Chelkov G, Chen G, Chen HS, Chen JC, Chen ML, Chen S, Chen SJ, Chen X, Chen XR, Chen YB, Cheng HP, Chu XK, Cibinetto G, Dai HL, Dai JP, Dbeyssi A, Dedovich D, Deng ZY, Denig A, Denysenko I, Destefanis M, De Mori F, Ding Y, Dong C, Dong J, Dong LY, Dong MY, Dou ZL, Du SX, Duan PF, Fan JZ, Fang J, Fang SS, Fang X, Fang Y, Farinelli R, Fava L, Fedorov O, Fegan S, Feldbauer F, Felici G, Feng CQ, Fioravanti E, Fritsch M, Fu CD, Gao Q, Gao XL, Gao Y, Gao Z, Garzia I, Goetzen K, Gong L, Gong WX, Gradl W, Greco M, Gu MH, Gu YT, Guan YH, Guo AQ, Guo LB, Guo RP, Guo Y, Guo YP, Haddadi Z, Hafner A, Han S, Hao XQ, Harris FA, He KL, Heinsius FH, Held T, Heng YK, Holtmann T, Hou ZL, Hu C, Hu HM, Hu JF, Hu T, Hu Y, Huang GS, Huang JS, Huang XT, Huang XZ, Huang Y, Huang ZL, Hussain T, Ji Q, Ji QP, Ji XB, Ji XL, Jiang LW, Jiang XS, Jiang XY, Jiao JB, Jiao Z, Jin DP, Jin S, Johansson T, Julin A, Kalantar-Nayestanaki N, Kang XL, Kang XS, Kavatsyuk M, Ke BC, Kiese P, Kliemt R, Kloss B, Kolcu OB, Kopf B, Kornicer M, Kupsc A, Kühn W, Lange JS, Lara M, Larin P, Leithoff H, Leng C, Li C, Li C, Li DM, Li F, Li FY, Li G, Li HB, Li HJ, Li JC, Li J, Li K, Li K, Li L, Li PR, Li QY, Li T, Li WD, Li WG, Li XL, Li XN, Li XQ, Li YB, Li ZB, Liang H, Liang YF, Liang YT, Liao GR, Lin DX, Liu B, Liu BJ, Liu CX, Liu D, Liu FH, Liu F, Liu F, Liu HB, Liu HH, Liu HH, Liu HM, Liu J, Liu JB, Liu JP, Liu JY, Liu K, Liu KY, Liu LD, Liu PL, Liu Q, Liu SB, Liu X, Liu YB, Liu YY, Liu ZA, Liu Z, Loehner H, Long YF, Lou XC, Lu HJ, Lu JG, Lu Y, Lu YP, Luo CL, Luo MX, Luo T, Luo XL, Lyu XR, Ma FC, Ma HL, Ma LL, Ma MM, Ma QM, Ma T, Ma XN, Ma XY, Ma YM, Maas FE, Maggiora M, Malik QA, Mao YJ, Mao ZP, Marcello S, Messchendorp JG, Mezzadri G, Min J, Min TJ, Mitchell RE, Mo XH, Mo YJ, Morales CM, Muchnoi NY, Muramatsu H, Musiol P, Nefedov Y, Nerling F, Nikolaev IB, Ning Z, Nisar S, Niu SL, Niu XY, Olsen SL, Ouyang Q, Pacetti S, Pan Y, Patteri P, Pelizaeus M, Peng HP, Peters K, Pettersson J, Ping JL, Ping RG, Poling R, Prasad V, Qi HR, Qi M, Qian S, Qiao CF, Qin LQ, Qin N, Qin XS, Qin ZH, Qiu JF, Rashid KH, Redmer CF, Ripka M, Rong G, Rosner C, Ruan XD, Sarantsev A, Savrié M, Schnier C, Schoenning K, Schumann S, Shan W, Shao M, Shen CP, Shen PX, Shen XY, Sheng HY, Shi M, Song WM, Song XY, Sosio S, Spataro S, Sun GX, Sun JF, Sun SS, Sun XH, Sun YJ, Sun YZ, Sun ZJ, Sun ZT, Tang CJ, Tang X, Tapan I, Thorndike EH, Tiemens M, Uman I, Varner GS, Wang B, Wang BL, Wang D, Wang DY, Wang K, Wang LL, Wang LS, Wang M, Wang P, Wang PL, Wang W, Wang WP, Wang XF, Wang Y, Wang YD, Wang YF, Wang YQ, Wang Z, Wang ZG, Wang ZH, Wang ZY, Wang ZY, Weber T, Wei DH, Weidenkaff P, Wen SP, Wiedner U, Wolke M, Wu LH, Wu LJ, Wu Z, Xia L, Xia LG, Xia Y, Xiao D, Xiao H, Xiao ZJ, Xie YG, Xiu QL, Xu GF, Xu JJ, Xu L, Xu QJ, Xu QN, Xu XP, Yan L, Yan WB, Yan WC, Yan YH, Yang HJ, Yang HX, Yang L, Yang YX, Ye M, Ye MH, Yin JH, You ZY, Yu BX, Yu CX, Yu JS, Yuan CZ, Yuan WL, Yuan Y, Yuncu A, Zafar AA, Zallo A, Zeng Y, Zeng Z, Zhang BX, Zhang BY, Zhang C, Zhang CC, Zhang DH, Zhang HH, Zhang HY, Zhang J, Zhang JJ, Zhang JL, Zhang JQ, Zhang JW, Zhang JY, Zhang JZ, Zhang K, Zhang L, Zhang SQ, Zhang XY, Zhang Y, Zhang Y, Zhang YH, Zhang YN, Zhang YT, Zhang Y, Zhang ZH, Zhang ZP, Zhang ZY, Zhao G, Zhao JW, Zhao JY, Zhao JZ, Zhao L, Zhao L, Zhao MG, Zhao Q, Zhao QW, Zhao SJ, Zhao TC, Zhao YB, Zhao ZG, Zhemchugov A, Zheng B, Zheng JP, Zheng WJ, Zheng YH, Zhong B, Zhou L, Zhou X, Zhou XK, Zhou XR, Zhou XY, Zhu K, Zhu KJ, Zhu S, Zhu SH, Zhu XL, Zhu YC, Zhu YS, Zhu ZA, Zhuang J, Zotti L, Zou BS, and Zou JH
- Abstract
Using a low background data sample of 9.7×10^{5} J/ψ→γη^{'}, η^{'}→γπ^{+}π^{-} events, which are 2 orders of magnitude larger than those from the previous experiments, recorded with the BESIII detector at BEPCII, the decay dynamics of η^{'}→γπ^{+}π^{-} are studied with both model-dependent and model-independent approaches. The contributions of ω and the ρ(770)-ω interference are observed for the first time in the decays η^{'}→γπ^{+}π^{-} in both approaches. Additionally, a contribution from the box anomaly or the ρ(1450) resonance is required in the model-dependent approach, while the process specific part of the decay amplitude is determined in the model-independent approach.
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- 2018
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39. Search for γ-Ray Line Signals from Dark Matter Annihilations in the Inner Galactic Halo from 10 Years of Observations with H.E.S.S.
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Abdallah H, Abramowski A, Aharonian F, Ait Benkhali F, Angüner EO, Arakawa M, Arrieta M, Aubert P, Backes M, Balzer A, Barnard M, Becherini Y, Becker Tjus J, Berge D, Bernhard S, Bernlöhr K, Blackwell R, Böttcher M, Boisson C, Bolmont J, Bonnefoy S, Bordas P, Bregeon J, Brun F, Brun P, Bryan M, Büchele M, Bulik T, Capasso M, Caroff S, Carosi A, Carr J, Casanova S, Cerruti M, Chakraborty N, Chaves RCG, Chen A, Chevalier J, Colafrancesco S, Condon B, Conrad J, Davids ID, Decock J, Deil C, Devin J, deWilt P, Dirson L, Djannati-Ataï A, Domainko W, Donath A, Drury LO, Dutson K, Dyks J, Edwards T, Egberts K, Eger P, Emery G, Ernenwein JP, Eschbach S, Farnier C, Fegan S, Fernandes MV, Fiasson A, Fontaine G, Förster A, Funk S, Füßling M, Gabici S, Gallant YA, Garrigoux T, Gaté F, Giavitto G, Giebels B, Glawion D, Glicenstein JF, Gottschall D, Grondin MH, Hahn J, Haupt M, Hawkes J, Heinzelmann G, Henri G, Hermann G, Hinton JA, Hofmann W, Hoischen C, Holch TL, Holler M, Horns D, Ivascenko A, Iwasaki H, Jacholkowska A, Jamrozy M, Janiak M, Jankowsky D, Jankowsky F, Jingo M, Jouvin L, Jung-Richardt I, Kastendieck MA, Katarzyński K, Katsuragawa M, Katz U, Kerszberg D, Khangulyan D, Khélifi B, King J, Klepser S, Klochkov D, Kluźniak W, Komin N, Kosack K, Krakau S, Kraus M, Krüger PP, Laffon H, Lamanna G, Lau J, Lees JP, Lefaucheur J, Lemière A, Lemoine-Goumard M, Lenain JP, Leser E, Liu R, Lohse T, Lorentz M, López-Coto R, Lypova I, Malyshev D, Marandon V, Marcowith A, Mariaud C, Marx R, Maurin G, Maxted N, Mayer M, Meintjes PJ, Meyer M, Mitchell AMW, Moderski R, Mohamed M, Mohrmann L, Morå K, Moulin E, Murach T, Nakashima S, de Naurois M, Ndiyavala H, Niederwanger F, Niemiec J, Oakes L, O'Brien P, Odaka H, Ohm S, Ostrowski M, Oya I, Padovani M, Panter M, Parsons RD, Pekeur NW, Pelletier G, Perennes C, Petrucci PO, Peyaud B, Piel Q, Pita S, Poireau V, Poon H, Prokhorov D, Prokoph H, Pühlhofer G, Punch M, Quirrenbach A, Raab S, Rauth R, Reimer A, Reimer O, Renaud M, de Los Reyes R, Rieger F, Rinchiuso L, Romoli C, Rowell G, Rudak B, Rulten CB, Sahakian V, Saito S, Sanchez DA, Santangelo A, Sasaki M, Schandri M, Schlickeiser R, Schüssler F, Schulz A, Schwanke U, Schwemmer S, Seglar-Arroyo M, Settimo M, Seyffert AS, Shafi N, Shilon I, Shiningayamwe K, Simoni R, Sol H, Spanier F, Spir-Jacob M, Stawarz Ł, Steenkamp R, Stegmann C, Steppa C, Sushch I, Takahashi T, Tavernet JP, Tavernier T, Taylor AM, Terrier R, Tibaldo L, Tiziani D, Tluczykont M, Trichard C, Tsirou M, Tsuji N, Tuffs R, Uchiyama Y, van der Walt J, van Eldik C, van Rensburg C, van Soelen B, Vasileiadis G, Veh J, Venter C, Viana A, Vincent P, Vink J, Voisin F, Völk HJ, Vuillaume T, Wadiasingh Z, Wagner SJ, Wagner P, Wagner RM, White R, Wierzcholska A, Willmann P, Wörnlein A, Wouters D, Yang R, Zaborov D, Zacharias M, Zanin R, Zdziarski AA, Zech A, Zefi F, Ziegler A, Zorn J, and Żywucka N
- Abstract
Spectral lines are among the most powerful signatures for dark matter (DM) annihilation searches in very-high-energy γ rays. The central region of the Milky Way halo is one of the most promising targets given its large amount of DM and proximity to Earth. We report on a search for a monoenergetic spectral line from self-annihilations of DM particles in the energy range from 300 GeV to 70 TeV using a two-dimensional maximum likelihood method taking advantage of both the spectral and spatial features of the signal versus background. The analysis makes use of Galactic center observations accumulated over ten years (2004-2014) with the H.E.S.S. array of ground-based Cherenkov telescopes. No significant γ-ray excess above the background is found. We derive upper limits on the annihilation cross section ⟨σv⟩ for monoenergetic DM lines at the level of 4×10^{-28} cm^{3} s^{-1} at 1 TeV, assuming an Einasto DM profile for the Milky Way halo. For a DM mass of 1 TeV, they improve over the previous ones by a factor of 6. The present constraints are the strongest obtained so far for DM particles in the mass range 300 GeV-70 TeV. Ground-based γ-ray observations have reached sufficient sensitivity to explore relevant velocity-averaged cross sections for DM annihilation into two γ-ray photons at the level expected from the thermal relic density for TeV DM particles.
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- 2018
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40. Precision Measurement of the e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} Cross Section Near Threshold.
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Ablikim M, Achasov MN, Ahmed S, Albrecht M, Alekseev M, Amoroso A, An FF, An Q, Bai JZ, Bai Y, Bakina O, Baldini Ferroli R, Ban Y, Begzsuren K, Bennett DW, Bennett JV, Berger N, Bertani M, Bettoni D, Bianchi F, Boger E, Boyko I, Briere RA, Cai H, Cai X, Cakir O, Calcaterra A, Cao GF, Cetin SA, Chai J, Chang JF, Chelkov G, Chen G, Chen HS, Chen JC, Chen ML, Chen PL, Chen SJ, Chen XR, Chen YB, Chu XK, Cibinetto G, Cossio F, Dai HL, Dai JP, Dbeyssi A, Dedovich D, Deng ZY, Denig A, Denysenko I, Destefanis M, De Mori F, Ding Y, Dong C, Dong J, Dong LY, Dong MY, Dou ZL, Du SX, Duan PF, Fang J, Fang SS, Fang Y, Farinelli R, Fava L, Fegan S, Feldbauer F, Felici G, Feng CQ, Fioravanti E, Fritsch M, Fu CD, Gao Q, Gao XL, Gao Y, Gao YG, Gao Z, Garillon B, Garzia I, Gilman A, Goetzen K, Gong L, Gong WX, Gradl W, Greco M, Gu MH, Gu YT, Guo AQ, Guo RP, Guo YP, Guskov A, Haddadi Z, Han S, Hao XQ, Harris FA, He KL, He XQ, Heinsius FH, Held T, Heng YK, Holtmann T, Hou ZL, Hu HM, Hu JF, Hu T, Hu Y, Huang GS, Huang JS, Huang XT, Huang XZ, Huang ZL, Hussain T, Ikegami Andersson W, Ji Q, Ji QP, Ji XB, Ji XL, Jiang XS, Jiang XY, Jiao JB, Jiao Z, Jin DP, Jin S, Jin Y, Johansson T, Julin A, Kalantar-Nayestanaki N, Kang XS, Kavatsyuk M, Ke BC, Khan T, Khoukaz A, Kiese P, Kliemt R, Koch L, Kolcu OB, Kopf B, Kornicer M, Kuemmel M, Kuhlmann M, Kupsc A, Kühn W, Lange JS, Lara M, Larin P, Lavezzi L, Leithoff H, Li C, Li C, Li DM, Li F, Li FY, Li G, Li HB, Li HJ, Li JC, Li JW, Li J, Li KJ, Li K, Li K, Li L, Li PL, Li PR, Li QY, Li WD, Li WG, Li XL, Li XN, Li XQ, Li ZB, Liang H, Liang YF, Liang YT, Liao GR, Libby J, Lin CX, Lin DX, Liu B, Liu BJ, Liu CX, Liu D, Liu FH, Liu F, Liu F, Liu HB, Liu HL, Liu HM, Liu H, Liu H, Liu JB, Liu JY, Liu K, Liu KY, Liu K, Liu LD, Liu Q, Liu SB, Liu X, Liu YB, Liu ZA, Liu Z, Long YF, Lou XC, Lu HJ, Lu JG, Lu Y, Lu YP, Luo CL, Luo MX, Luo XL, Lusso S, Lyu XR, Ma FC, Ma HL, Ma LL, Ma MM, Ma QM, Ma T, Ma XN, Ma XY, Ma YM, Maas FE, Maggiora M, Malik QA, Mao YJ, Mao ZP, Marcello S, Meng ZX, Messchendorp JG, Mezzadri G, Min J, Mitchell RE, Mo XH, Mo YJ, Morales Morales C, Muchnoi NY, Muramatsu H, Mustafa A, Nefedov Y, Nerling F, Nikolaev IB, Ning Z, Nisar S, Niu SL, Niu XY, Olsen SL, Ouyang Q, Pacetti S, Pan Y, Papenbrock M, Patteri P, Pelizaeus M, Pellegrino J, Peng HP, Peng ZY, Peters K, Pettersson J, Ping JL, Ping RG, Pitka A, Poling R, Prasad V, Qi HR, Qi M, Qi TY, Qian S, Qiao CF, Qin N, Qin XS, Qin ZH, Qiu JF, Rashid KH, Redmer CF, Richter M, Ripka M, Rolo M, Rong G, Rosner C, Sarantsev A, Savrié M, Schnier C, Schoenning K, Shan W, Shan XY, Shao M, Shen CP, Shen PX, Shen XY, Sheng HY, Shi X, Song JJ, Song WM, Song XY, Sosio S, Sowa C, Spataro S, Sun GX, Sun JF, Sun L, Sun SS, Sun XH, Sun YJ, Sun YK, Sun YZ, Sun ZJ, Sun ZT, Tan YT, Tang CJ, Tang GY, Tang X, Tapan I, Tiemens M, Tsednee B, Uman I, Varner GS, Wang B, Wang BL, Wang D, Wang DY, Wang D, Wang K, Wang LL, Wang LS, Wang M, Wang M, Wang P, Wang PL, Wang WP, Wang XF, Wang Y, Wang YD, Wang YF, Wang YQ, Wang Z, Wang ZG, Wang ZY, Wang Z, Weber T, Wei DH, Wei JH, Weidenkaff P, Wen SP, Wiedner U, Wolke M, Wu LH, Wu LJ, Wu Z, Xia L, Xia Y, Xiao D, Xiao YJ, Xiao ZJ, Xie YG, Xie YH, Xiong XA, Xiu QL, Xu GF, Xu JJ, Xu L, Xu QJ, Xu QN, Xu XP, Yan F, Yan L, Yan WB, Yan WC, Yan YH, Yang HJ, Yang HX, Yang L, Yang YH, Yang YX, Yang Y, Ye M, Ye MH, Yin JH, You ZY, Yu BX, Yu CX, Yu JS, Yuan CZ, Yuan Y, Yuncu A, Zafar AA, Zeng Y, Zeng Z, Zhang BX, Zhang BY, Zhang CC, Zhang DH, Zhang HH, Zhang HY, Zhang J, Zhang JL, Zhang JQ, Zhang JW, Zhang JY, Zhang JZ, Zhang K, Zhang L, Zhang SQ, Zhang XY, Zhang Y, Zhang YH, Zhang YT, Zhang Y, Zhang Y, Zhang Y, Zhang ZH, Zhang ZP, Zhang ZY, Zhao G, Zhao JW, Zhao JY, Zhao JZ, Zhao L, Zhao L, Zhao MG, Zhao Q, Zhao SJ, Zhao TC, Zhao YB, Zhao ZG, Zhemchugov A, Zheng B, Zheng JP, Zheng YH, Zhong B, Zhou L, Zhou Q, Zhou X, Zhou XK, Zhou XR, Zhou XY, Zhu AN, Zhu J, Zhu K, Zhu KJ, Zhu S, Zhu SH, Zhu XL, Zhu YC, Zhu YS, Zhu ZA, Zhuang J, Zou BS, and Zou JH
- Abstract
The cross section of the e^{+}e^{-}→Λ_{c}^{+}Λ[over ¯]_{c}^{-} process is measured with unprecedented precision using data collected with the BESIII detector at sqrt[s]=4574.5, 4580.0, 4590.0 and 4599.5 MeV. The nonzero cross section near the Λ_{c}^{+}Λ[over ¯]_{c}^{-} production threshold is cleared. At center-of-mass energies sqrt[s]=4574.5 and 4599.5 MeV, the higher statistics data enable us to measure the Λ_{c} polar angle distributions. From these, the Λ_{c} electric over magnetic form-factor ratios (|G_{E}/G_{M}|) are measured for the first time. They are found to be 1.14±0.14±0.07 and 1.23±0.05±0.03, respectively, where the first uncertainties are statistical and the second are systematic.
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- 2018
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41. First Exclusive Measurement of Deeply Virtual Compton Scattering off ^{4}He: Toward the 3D Tomography of Nuclei.
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Hattawy M, Baltzell NA, Dupré R, Hafidi K, Stepanyan S, Bültmann S, De Vita R, El Alaoui A, El Fassi L, Egiyan H, Girod FX, Guidal M, Jenkins D, Liuti S, Perrin Y, Torayev B, Voutier E, Adhikari KP, Adhikari S, Adikaram D, Akbar Z, Amaryan MJ, Anefalos Pereira S, Armstrong WR, Avakian H, Ball J, Bashkanov M, Battaglieri M, Batourine V, Bedlinskiy I, Biselli AS, Boiarinov S, Briscoe WJ, Brooks WK, Burkert VD, Thanh Cao F, Carman DS, Celentano A, Charles G, Chetry T, Ciullo G, Clark L, Colaneri L, Cole PL, Contalbrigo M, Cortes O, Crede V, D'Angelo A, Dashyan N, De Sanctis E, Deur A, Djalali C, Elouadrhiri L, Eugenio P, Fedotov G, Fegan S, Fersch R, Filippi A, Fleming JA, Forest TA, Fradi A, Garçon M, Gevorgyan N, Ghandilyan Y, Gilfoyle GP, Giovanetti KL, Gleason C, Gohn W, Golovatch E, Gothe RW, Griffioen KA, Guo L, Hakobyan H, Hanretty C, Harrison N, Heddle D, Hicks K, Holtrop M, Hughes SM, Ireland DG, Ishkhanov BS, Isupov EL, Jiang H, Joo K, Joosten S, Keller D, Khachatryan G, Khachatryan M, Khandaker M, Kim A, Kim W, Klein A, Klein FJ, Kubarovsky V, Kuhn SE, Kuleshov SV, Lanza L, Lenisa P, Livingston K, Lu HY, MacGregor IJD, Markov N, Mayer M, McCracken ME, McKinnon B, Meyer CA, Meziani ZE, Mineeva T, Mirazita M, Mokeev V, Montgomery RA, Moutarde H, Movsisyan A, Munoz Camacho C, Nadel-Turonski P, Net LA, Niccolai S, Niculescu G, Niculescu I, Osipenko M, Ostrovidov AI, Paolone M, Paremuzyan R, Park K, Pasyuk E, Phelps E, Phelps W, Pisano S, Pogorelko O, Price JW, Prok Y, Protopopescu D, Ripani M, Ritchie BG, Rizzo A, Rosner G, Rossi P, Sabatié F, Salgado C, Schumacher RA, Seder E, Sharabian YG, Simonyan A, Skorodumina I, Smith GD, Sokhan D, Sparveris N, Strauch S, Taiuti M, Ungaro M, Voskanyan H, Walford NK, Watts DP, Wei X, Weinstein LB, Wood MH, Zachariou N, Zana L, Zhang J, and Zhao ZW
- Abstract
We report on the first measurement of the beam-spin asymmetry in the exclusive process of coherent deeply virtual Compton scattering off a nucleus. The experiment uses the 6 GeV electron beam from the Continuous Electron Beam Accelerator Facility (CEBAF) accelerator at Jefferson Lab incident on a pressurized ^{4}He gaseous target placed in front of the CEBAF Large Acceptance Spectrometer (CLAS). The scattered electron is detected by CLAS and the photon by a dedicated electromagnetic calorimeter at forward angles. To ensure the exclusivity of the process, a specially designed radial time projection chamber is used to detect the recoiling ^{4}He nuclei. We measure beam-spin asymmetries larger than those observed on the free proton in the same kinematic domain. From these, we are able to extract, in a model-independent way, the real and imaginary parts of the only ^{4}He Compton form factor, H_{A}. This first measurement of coherent deeply virtual Compton scattering on the ^{4}He nucleus, with a fully exclusive final state via nuclear recoil tagging, leads the way toward 3D imaging of the partonic structure of nuclei.
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- 2017
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42. Beam-Target Helicity Asymmetry for γ[over →]n[over →]→π^{-}p in the N^{*} Resonance Region.
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Ho D, Peng P, Bass C, Collins P, D'Angelo A, Deur A, Fleming J, Hanretty C, Kageya T, Khandaker M, Klein FJ, Klempt E, Laine V, Lowry MM, Lu H, Nepali C, Nikonov VA, O'Connell T, Sandorfi AM, Sarantsev AV, Schumacher RA, Strakovsky II, Švarc A, Walford NK, Wei X, Whisnant CS, Workman RL, Zonta I, Adhikari KP, Adikaram D, Akbar Z, Amaryan MJ, Anefalos Pereira S, Avakian H, Ball J, Bashkanov M, Battaglieri M, Batourine V, Bedlinskiy I, Biselli A, Briscoe WJ, Burkert VD, Carman DS, Celentano A, Charles G, Chetry T, Ciullo G, Clark L, Colaneri L, Cole PL, Contalbrigo M, Crede V, Dashyan N, De Sanctis E, De Vita R, Djalali C, Dupre R, El Alaoui A, El Fassi L, Elouadrhiri L, Eugenio P, Fedotov G, Fegan S, Fersch R, Filippi A, Fradi A, Ghandilyan Y, Gilfoyle GP, Girod FX, Glazier DI, Gleason C, Gohn W, Golovatch E, Gothe RW, Griffioen KA, Guidal M, Guo L, Hakobyan H, Harrison N, Hattawy M, Hicks K, Holtrop M, Hughes SM, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Jenkins D, Jiang H, Jo HS, Joo K, Joosten S, Keller D, Khachatryan G, Kim A, Kim W, Klein A, Kubarovsky V, Kuleshov SV, Lanza L, Lenisa P, Livingston K, MacGregor IJD, Markov N, McKinnon B, Mineeva T, Mokeev V, Montgomery RA, Movsisyan A, Munoz Camacho C, Murdoch G, Niccolai S, Niculescu G, Osipenko M, Paolone M, Paremuzyan R, Park K, Pasyuk E, Phelps W, Pogorelko O, Price JW, Procureur S, Protopopescu D, Ripani M, Riser D, Ritchie BG, Rizzo A, Rosner G, Sabatié F, Salgado C, Sharabian YG, Skorodumina I, Smith GD, Sober DI, Sokhan D, Sparveris N, Strauch S, Tian Y, Torayev B, Ungaro M, Voskanyan H, Voutier E, Watts DP, Wood MH, Zachariou N, Zhang J, and Zhao ZW
- Abstract
We report the first beam-target double-polarization asymmetries in the γ+n(p)→π^{-}+p(p) reaction spanning the nucleon resonance region from invariant mass W=1500 to 2300 MeV. Circularly polarized photons and longitudinally polarized deuterons in solid hydrogen deuteride (HD) have been used with the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The exclusive final state has been extracted using three very different analyses that show excellent agreement, and these have been used to deduce the E polarization observable for an effective neutron target. These results have been incorporated into new partial wave analyses and have led to significant revisions for several γnN^{*} resonance photocouplings.
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- 2017
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43. Measurement of Singly Cabibbo Suppressed Decays Λ_{c}^{+}→pπ^{+}π^{-} and Λ_{c}^{+}→pK^{+}K^{-}.
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Ablikim M, Achasov MN, Ahmed S, Ai XC, Albayrak O, Albrecht M, Ambrose DJ, Amoroso A, An FF, An Q, Bai JZ, Bakina O, Baldini Ferroli R, Ban Y, Bennett DW, Bennett JV, Berger N, Bertani M, Bettoni D, Bian JM, Bianchi F, Boger E, Boyko I, Briere RA, Cai H, Cai X, Cakir O, Calcaterra A, Cao GF, Cetin SA, Chai J, Chang JF, Chelkov G, Chen G, Chen HS, Chen JC, Chen ML, Chen S, Chen SJ, Chen X, Chen XR, Chen YB, Cheng HP, Chu XK, Cibinetto G, Dai HL, Dai JP, Dbeyssi A, Dedovich D, Deng ZY, Denig A, Denysenko I, Destefanis M, De Mori F, Ding Y, Dong C, Dong J, Dong LY, Dong MY, Dou ZL, Du SX, Duan PF, Fan JZ, Fang J, Fang SS, Fang X, Fang Y, Farinelli R, Fava L, Fegan S, Feldbauer F, Felici G, Feng CQ, Fioravanti E, Fritsch M, Fu CD, Gao Q, Gao XL, Gao Y, Gao Z, Garzia I, Goetzen K, Gong L, Gong WX, Gradl W, Greco M, Gu MH, Gu YT, Guan YH, Guo AQ, Guo LB, Guo RP, Guo Y, Guo YP, Haddadi Z, Hafner A, Han S, Hao XQ, Harris FA, He KL, Heinsius FH, Held T, Heng YK, Holtmann T, Hou ZL, Hu C, Hu HM, Hu JF, Hu T, Hu Y, Huang GS, Huang JS, Huang XT, Huang XZ, Huang Y, Huang ZL, Hussain T, Ikegami Andersson W, Ji Q, Ji QP, Ji XB, Ji XL, Jiang LW, Jiang XS, Jiang XY, Jiao JB, Jiao Z, Jin DP, Jin S, Johansson T, Julin A, Kalantar-Nayestanaki N, Kang XL, Kang XS, Kavatsyuk M, Ke BC, Kiese P, Kliemt R, Kloss B, Kolcu OB, Kopf B, Kornicer M, Kupsc A, Kühn W, Lange JS, Lara M, Larin P, Leithoff H, Leng C, Li C, Li C, Li DM, Li F, Li FY, Li G, Li HB, Li HJ, Li JC, Li J, Li K, Li K, Li L, Li PL, Li PR, Li QY, Li T, Li WD, Li WG, Li XL, Li XN, Li XQ, Li YB, Li ZB, Liang H, Liang YF, Liang YT, Liao GR, Lin DX, Liu B, Liu BJ, Liu CX, Liu D, Liu FH, Liu F, Liu F, Liu HB, Liu HH, Liu HH, Liu HM, Liu J, Liu JB, Liu JP, Liu JY, Liu K, Liu KY, Liu LD, Liu PL, Liu Q, Liu SB, Liu X, Liu YB, Liu YY, Liu ZA, Liu Z, Loehner H, Long YF, Lou XC, Lu HJ, Lu JG, Lu Y, Lu YP, Luo CL, Luo MX, Luo T, Luo XL, Lyu XR, Ma FC, Ma HL, Ma LL, Ma MM, Ma QM, Ma T, Ma XN, Ma XY, Ma YM, Maas FE, Maggiora M, Malik QA, Mao YJ, Mao ZP, Marcello S, Messchendorp JG, Mezzadri G, Min J, Min TJ, Mitchell RE, Mo XH, Mo YJ, Morales Morales C, Muchnoi NY, Muramatsu H, Musiol P, Nefedov Y, Nerling F, Nikolaev IB, Ning Z, Nisar S, Niu SL, Niu XY, Olsen SL, Ouyang Q, Pacetti S, Pan Y, Patteri P, Pelizaeus M, Peng HP, Peters K, Pettersson J, Ping JL, Ping RG, Poling R, Prasad V, Qi HR, Qi M, Qian S, Qiao CF, Qin LQ, Qin N, Qin XS, Qin ZH, Qiu JF, Rashid KH, Redmer CF, Ripka M, Rong G, Rosner C, Ruan XD, Sarantsev A, Savrié M, Schnier C, Schoenning K, Schumann S, Shan W, Shao M, Shen CP, Shen PX, Shen XY, Sheng HY, Shi M, Song WM, Song XY, Sosio S, Spataro S, Sun GX, Sun JF, Sun SS, Sun XH, Sun YJ, Sun YZ, Sun ZJ, Sun ZT, Tang CJ, Tang X, Tapan I, Thorndike EH, Tiemens M, Uman I, Varner GS, Wang B, Wang BL, Wang D, Wang DY, Wang K, Wang LL, Wang LS, Wang M, Wang P, Wang PL, Wang W, Wang WP, Wang XF, Wang Y, Wang YD, Wang YF, Wang YQ, Wang Z, Wang ZG, Wang ZH, Wang ZY, Wang ZY, Weber T, Wei DH, Weidenkaff P, Wen SP, Wiedner U, Wolke M, Wu LH, Wu LJ, Wu Z, Xia L, Xia LG, Xia Y, Xiao D, Xiao H, Xiao ZJ, Xie YG, Xiu QL, Xu GF, Xu JJ, Xu L, Xu QJ, Xu QN, Xu XP, Yan L, Yan WB, Yan WC, Yan YH, Yang HJ, Yang HX, Yang L, Yang YX, Ye M, Ye MH, Yin JH, You ZY, Yu BX, Yu CX, Yu JS, Yuan CZ, Yuan WL, Yuan Y, Yuncu A, Zafar AA, Zallo A, Zeng Y, Zeng Z, Zhang BX, Zhang BY, Zhang C, Zhang CC, Zhang DH, Zhang HH, Zhang HY, Zhang J, Zhang JJ, Zhang JL, Zhang JQ, Zhang JW, Zhang JY, Zhang JZ, Zhang K, Zhang L, Zhang SQ, Zhang XY, Zhang Y, Zhang Y, Zhang YH, Zhang YN, Zhang YT, Zhang Y, Zhang ZH, Zhang ZP, Zhang ZY, Zhao G, Zhao JW, Zhao JY, Zhao JZ, Zhao L, Zhao L, Zhao MG, Zhao Q, Zhao QW, Zhao SJ, Zhao TC, Zhao YB, Zhao ZG, Zhemchugov A, Zheng B, Zheng JP, Zheng WJ, Zheng YH, Zhong B, Zhou L, Zhou X, Zhou XK, Zhou XR, Zhou XY, Zhu K, Zhu KJ, Zhu S, Zhu SH, Zhu XL, Zhu YC, Zhu YS, Zhu ZA, Zhuang J, Zotti L, Zou BS, and Zou JH
- Abstract
Using 567 pb^{-1} of data collected with the BESIII detector at a center-of-mass energy of sqrt[s]=4.599 GeV, near the Λ_{c}^{+}Λ[over ¯]_{c}^{-} threshold, we study the singly Cabibbo-suppressed decays Λ_{c}^{+}→pπ^{+}π^{-} and Λ_{c}^{+}→pK^{+}K^{-}. By normalizing with respect to the Cabibbo-favored decay Λ_{c}^{+}→pK^{-}π^{+}, we obtain ratios of branching fractions: [B(Λ_{c}^{+}→pπ^{+}π^{-})/B(Λ_{c}^{+}→pK^{-}π^{+})]=(6.70±0.48±0.25)%, [B(Λ_{c}^{+}→pϕ)/B(Λ_{c}^{+}→pK^{-}π^{+})]=(1.81±0.33±0.13)%, and [B(Λ_{c}^{+}→pK^{+}K_{non-ϕ}^{-})/B(Λ_{c}^{+}→pK^{-}π^{+})]=(9.36±2.22±0.71)×10^{-3}, where the uncertainties are statistical and systematic, respectively. The absolute branching fractions are also presented. Among these measurements, the decay Λ_{c}^{+}→pπ^{+}π^{-} is observed for the first time, and the precision of the branching fraction for Λ_{c}^{+}→pK^{+}K_{non-ϕ}^{-} and Λ_{c}^{+}→pϕ is significantly improved.
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- 2016
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44. H.E.S.S. Limits on Linelike Dark Matter Signatures in the 100 GeV to 2 TeV Energy Range Close to the Galactic Center.
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Abdalla H, Abramowski A, Aharonian F, Ait Benkhali F, Akhperjanian AG, Andersson T, Angüner EO, Arrieta M, Aubert P, Backes M, Balzer A, Barnard M, Becherini Y, Becker Tjus J, Berge D, Bernhard S, Bernlöhr K, Birsin E, Blackwell R, Böttcher M, Boisson C, Bolmont J, Bordas P, Bregeon J, Brun F, Brun P, Bryan M, Bulik T, Capasso M, Carr J, Casanova S, Chakraborty N, Chalme-Calvet R, Chaves RC, Chen A, Chevalier J, Chrétien M, Colafrancesco S, Cologna G, Condon B, Conrad J, Couturier C, Cui Y, Davids ID, Degrange B, Deil C, Devin J, deWilt P, Djannati-Ataï A, Domainko W, Donath A, Drury LO, Dubus G, Dutson K, Dyks J, Dyrda M, Edwards T, Egberts K, Eger P, Ernenwein JP, Eschbach S, Farnier C, Fegan S, Fernandes MV, Fiasson A, Fontaine G, Förster A, Funk S, Füßling M, Gabici S, Gajdus M, Gallant YA, Garrigoux T, Giavitto G, Giebels B, Glicenstein JF, Gottschall D, Goyal A, Grondin MH, Grudzińska M, Hadasch D, Hahn J, Hawkes J, Heinzelmann G, Henri G, Hermann G, Hervet O, Hillert A, Hinton JA, Hofmann W, Hoischen C, Holler M, Horns D, Ivascenko A, Jacholkowska A, Jamrozy M, Janiak M, Jankowsky D, Jankowsky F, Jingo M, Jogler T, Jouvin L, Jung-Richardt I, Kastendieck MA, Katarzyński K, Katz U, Kerszberg D, Khélifi B, Kieffer M, King J, Klepser S, Klochkov D, Kluźniak W, Kolitzus D, Komin N, Kosack K, Krakau S, Kraus M, Krayzel F, Krüger PP, Laffon H, Lamanna G, Lau J, Lees JP, Lefaucheur J, Lefranc V, Lemière A, Lemoine-Goumard M, Lenain JP, Leser E, Liu R, Lohse T, Lorentz M, Lypova I, Marandon V, Marcowith A, Mariaud C, Marx R, Maurin G, Maxted N, Mayer M, Meintjes PJ, Meyer M, Mitchell AM, Moderski R, Mohamed M, Morå K, Moulin E, Murach T, de Naurois M, Niederwanger F, Niemiec J, Oakes L, O'Brien P, Odaka H, Ohm S, Ostrowski M, Öttl S, Oya I, Padovani M, Panter M, Parsons RD, Paz Arribas M, Pekeur NW, Pelletier G, Perennes C, Petrucci PO, Peyaud B, Pita S, Poon H, Prokhorov D, Prokoph H, Pühlhofer G, Punch M, Quirrenbach A, Raab S, Reimer A, Reimer O, Renaud M, de Los Reyes R, Rieger F, Romoli C, Rosier-Lees S, Rowell G, Rudak B, Rulten CB, Sahakian V, Salek D, Sanchez DA, Santangelo A, Sasaki M, Schlickeiser R, Schüssler F, Schulz A, Schwanke U, Schwemmer S, Settimo M, Seyffert AS, Shafi N, Shilon I, Simoni R, Sol H, Spanier F, Spengler G, Spies F, Stawarz Ł, Steenkamp R, Stegmann C, Stinzing F, Stycz K, Sushch I, Tavernet JP, Tavernier T, Taylor AM, Terrier R, Tibaldo L, Tluczykont M, Trichard C, Tuffs R, van der Walt J, van Eldik C, van Soelen B, Vasileiadis G, Veh J, Venter C, Viana A, Vincent P, Vink J, Voisin F, Völk HJ, Vuillaume T, Wadiasingh Z, Wagner SJ, Wagner P, Wagner RM, White R, Wierzcholska A, Willmann P, Wörnlein A, Wouters D, Yang R, Zabalza V, Zaborov D, Zacharias M, Zdziarski AA, Zech A, Zefi F, Ziegler A, and Żywucka N
- Abstract
A search for dark matter linelike signals iss performed in the vicinity of the Galactic Center by the H.E.S.S. experiment on observational data taken in 2014. An unbinned likelihood analysis iss developed to improve the sensitivity to linelike signals. The upgraded analysis along with newer data extend the energy coverage of the previous measurement down to 100 GeV. The 18 h of data collected with the H.E.S.S. array allow one to rule out at 95% C.L. the presence of a 130 GeV line (at l=-1.5°, b=0° and for a dark matter profile centered at this location) previously reported in Fermi-LAT data. This new analysis overlaps significantly in energy with previous Fermi-LAT and H.E.S.S., Results: No significant excess associated with dark matter annihilations was found in the energy range of 100 GeV to 2 TeV and upper limits on the gamma-ray flux and the velocity weighted annihilation cross section are derived adopting an Einasto dark matter halo profile. Expected limits for present and future large statistics H.E.S.S. observations are also given.
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- 2016
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45. Search for Dark Matter Annihilations towards the Inner Galactic Halo from 10 Years of Observations with H.E.S.S.
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Abdallah H, Abramowski A, Aharonian F, Ait Benkhali F, Akhperjanian AG, Angüner E, Arrieta M, Aubert P, Backes M, Balzer A, Barnard M, Becherini Y, Becker Tjus J, Berge D, Bernhard S, Bernlöhr K, Birsin E, Blackwell R, Böttcher M, Boisson C, Bolmont J, Bordas P, Bregeon J, Brun F, Brun P, Bryan M, Bulik T, Capasso M, Carr J, Casanova S, Chakraborty N, Chalme-Calvet R, Chaves RC, Chen A, Chevalier J, Chrétien M, Colafrancesco S, Cologna G, Condon B, Conrad J, Couturier C, Cui Y, Davids ID, Degrange B, Deil C, deWilt P, Djannati-Ataï A, Domainko W, Donath A, Drury LO, Dubus G, Dutson K, Dyks J, Dyrda M, Edwards T, Egberts K, Eger P, Ernenwein JP, Eschbach S, Farnier C, Fegan S, Fernandes MV, Fiasson A, Fontaine G, Förster A, Funk S, Füßling M, Gabici S, Gajdus M, Gallant YA, Garrigoux T, Giavitto G, Giebels B, Glicenstein JF, Gottschall D, Goyal A, Grondin MH, Grudzińska M, Hadasch D, Hahn J, Hawkes J, Heinzelmann G, Henri G, Hermann G, Hervet O, Hillert A, Hinton JA, Hofmann W, Hoischen C, Holler M, Horns D, Ivascenko A, Jacholkowska A, Jamrozy M, Janiak M, Jankowsky D, Jankowsky F, Jingo M, Jogler T, Jouvin L, Jung-Richardt I, Kastendieck MA, Katarzyński K, Katz U, Kerszberg D, Khélifi B, Kieffer M, King J, Klepser S, Klochkov D, Kluźniak W, Kolitzus D, Komin N, Kosack K, Krakau S, Kraus M, Krayzel F, Krüger PP, Laffon H, Lamanna G, Lau J, Lees JP, Lefaucheur J, Lefranc V, Lemière A, Lemoine-Goumard M, Lenain JP, Leser E, Lohse T, Lorentz M, Lui R, Lypova I, Marandon V, Marcowith A, Mariaud C, Marx R, Maurin G, Maxted N, Mayer M, Meintjes PJ, Menzler U, Meyer M, Mitchell AM, Moderski R, Mohamed M, Morå K, Moulin E, Murach T, de Naurois M, Niederwanger F, Niemiec J, Oakes L, Odaka H, Ohm S, Öttl S, Ostrowski M, Oya I, Padovani M, Panter M, Parsons RD, Paz Arribas M, Pekeur NW, Pelletier G, Petrucci PO, Peyaud B, Pita S, Poon H, Prokhorov D, Prokoph H, Pühlhofer G, Punch M, Quirrenbach A, Raab S, Reimer A, Reimer O, Renaud M, de Los Reyes R, Rieger F, Romoli C, Rosier-Lees S, Rowell G, Rudak B, Rulten CB, Sahakian V, Salek D, Sanchez DA, Santangelo A, Sasaki M, Schlickeiser R, Schüssler F, Schulz A, Schwanke U, Schwemmer S, Seyffert AS, Shafi N, Simoni R, Sol H, Spanier F, Spengler G, Spieß F, Stawarz L, Steenkamp R, Stegmann C, Stinzing F, Stycz K, Sushch I, Tavernet JP, Tavernier T, Taylor AM, Terrier R, Tluczykont M, Trichard C, Tuffs R, van der Walt J, van Eldik C, van Soelen B, Vasileiadis G, Veh J, Venter C, Viana A, Vincent P, Vink J, Voisin F, Völk HJ, Vuillaume T, Wadiasingh Z, Wagner SJ, Wagner P, Wagner RM, White R, Wierzcholska A, Willmann P, Wörnlein A, Wouters D, Yang R, Zabalza V, Zaborov D, Zacharias M, Zdziarski AA, Zech A, Zefi F, Ziegler A, and Żywucka N
- Abstract
The inner region of the Milky Way halo harbors a large amount of dark matter (DM). Given its proximity, it is one of the most promising targets to look for DM. We report on a search for the annihilations of DM particles using γ-ray observations towards the inner 300 pc of the Milky Way, with the H.E.S.S. array of ground-based Cherenkov telescopes. The analysis is based on a 2D maximum likelihood method using Galactic Center (GC) data accumulated by H.E.S.S. over the last 10 years (2004-2014), and does not show any significant γ-ray signal above background. Assuming Einasto and Navarro-Frenk-White DM density profiles at the GC, we derive upper limits on the annihilation cross section ⟨σv⟩. These constraints are the strongest obtained so far in the TeV DM mass range and improve upon previous limits by a factor 5. For the Einasto profile, the constraints reach ⟨σv⟩ values of 6×10^{-26} cm^{3} s^{-1} in the W^{+}W^{-} channel for a DM particle mass of 1.5 TeV, and 2×10^{-26} cm^{3} s^{-1} in the τ^{+}τ^{-} channel for a 1 TeV mass. For the first time, ground-based γ-ray observations have reached sufficient sensitivity to probe ⟨σv⟩ values expected from the thermal relic density for TeV DM particles.
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- 2016
- Full Text
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46. Resolving the Extragalactic γ-Ray Background above 50 GeV with the Fermi Large Area Telescope.
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Ackermann M, Ajello M, Albert A, Atwood WB, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Bissaldi E, Blandford RD, Bloom ED, Bonino R, Bregeon J, Britto RJ, Bruel P, Buehler R, Caliandro GA, Cameron RA, Caragiulo M, Caraveo PA, Cavazzuti E, Cecchi C, Charles E, Chekhtman A, Chiang J, Chiaro G, Ciprini S, Cohen-Tanugi J, Cominsky LR, Costanza F, Cutini S, D'Ammando F, de Angelis A, de Palma F, Desiante R, Digel SW, Di Mauro M, Di Venere L, Domínguez A, Drell PS, Favuzzi C, Fegan SJ, Ferrara EC, Franckowiak A, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Giglietto N, Giommi P, Giordano F, Giroletti M, Godfrey G, Green D, Grenier IA, Guiriec S, Hays E, Horan D, Iafrate G, Jogler T, Jóhannesson G, Kuss M, La Mura G, Larsson S, Latronico L, Li J, Li L, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Madejski GM, Magill J, Maldera S, Manfreda A, Mayer M, Mazziotta MN, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Negro M, Nuss E, Ohsugi T, Okada C, Omodei N, Orlando E, Ormes JF, Paneque D, Perkins JS, Pesce-Rollins M, Petrosian V, Piron F, Pivato G, Porter TA, Rainò S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reposeur T, Romani RW, Sánchez-Conde M, Schmid J, Schulz A, Sgrò C, Simone D, Siskind EJ, Spada F, Spandre G, Spinelli P, Suson DJ, Takahashi H, Thayer JB, Tibaldo L, Torres DF, Troja E, Vianello G, Yassine M, and Zimmer S
- Abstract
The Fermi Large Area Telescope (LAT) Collaboration has recently released a catalog of 360 sources detected above 50 GeV (2FHL). This catalog was obtained using 80 months of data re-processed with Pass 8, the newest event-level analysis, which significantly improves the acceptance and angular resolution of the instrument. Most of the 2FHL sources at high Galactic latitude are blazars. Using detailed Monte Carlo simulations, we measure, for the first time, the source count distribution, dN/dS, of extragalactic γ-ray sources at E>50 GeV and find that it is compatible with a Euclidean distribution down to the lowest measured source flux in the 2FHL (∼8×10^{-12} ph cm^{-2} s^{-1}). We employ a one-point photon fluctuation analysis to constrain the behavior of dN/dS below the source detection threshold. Overall, the source count distribution is constrained over three decades in flux and found compatible with a broken power law with a break flux, S_{b}, in the range [8×10^{-12},1.5×10^{-11}] ph cm^{-2} s^{-1} and power-law indices below and above the break of α_{2}∈[1.60,1.75] and α_{1}=2.49±0.12, respectively. Integration of dN/dS shows that point sources account for at least 86_{-14}^{+16}% of the total extragalactic γ-ray background. The simple form of the derived source count distribution is consistent with a single population (i.e., blazars) dominating the source counts to the minimum flux explored by this analysis. We estimate the density of sources detectable in blind surveys that will be performed in the coming years by the Cherenkov Telescope Array.
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- 2016
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47. Measurement of the high-energy gamma-ray emission from the Moon with the Fermi Large Area Telescope.
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Ackermann M, Ajello M, Albert A, Atwood WB, Baldini L, Barbiellini G, Bastieri D, Bellazzini R, Bissaldi E, Blandford RD, Bonino R, Bottacini E, Bregeon J, Bruel P, Buehler R, Caliandro GA, Cameron RA, Caragiulo M, Caraveo PA, Cavazzuti E, Cecchi C, Chekhtman A, Chiang J, Chiaro G, Ciprini S, Claus R, Cohen-Tanugi J, Costanza F, Cuoco A, Cutini S, D'Ammando F, de Angelis A, de Palma F, Desiante R, Digel SW, Di Venere L, Drell PS, Favuzzi C, Fegan SJ, Focke WB, Franckowiak A, Funk S, Fusco P, Gargano F, Gasparrini D, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier IA, Grove JE, Guiriec S, Harding AK, Hewitt JW, Horan D, Hou X, Iafrate G, Jóhannesson G, Kamae T, Kuss M, Larsson S, Latronico L, Li J, Li L, Longo F, Loparco F, Lovellette MN, Lubrano P, Magill J, Maldera S, Manfreda A, Mayer M, Mazziotta MN, Michelson PF, Mitthumsiri W, Mizuno T, Monzani ME, Morselli A, Murgia S, Nuss E, Omodei N, Orlando E, Ormes JF, Paneque D, Perkins JS, Pesce-Rollins M, Petrosian V, Piron F, Pivato G, Rainò S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Sgrò C, Siskind EJ, Spada F, Spandre G, Spinelli P, Takahashi H, Thayer JB, Thompson DJ, Tibaldo L, Torres DF, Tosti G, Troja E, Vianello G, Winer BL, Wood KS, Yassine M, Cerutti F, Ferrari A, and Sala PR
- Abstract
We have measured the gamma-ray emission spectrum of the Moon using the data collected by the Large Area Telescope onboard the Fermi satellite during its first seven years of operation, in the energy range from 30 MeV up to a few GeV. We have also studied the time evolution of the flux, finding a correlation with the solar activity. We have developed a full Monte Carlo simulation describing the interactions of cosmic rays with the lunar surface. The results of the present analysis can be explained in the framework of this model, where the production of gamma rays is due to the interactions of cosmic-ray proton and helium nuclei with the surface of the Moon. Finally, we have used our simulation to derive the cosmic-ray proton and helium spectra near Earth from the Moon gamma-ray data.
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- 2016
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48. Adherence to complementary feeding recommendations for infants and implications for public health.
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Fegan S, Bassett E, Peng Y, and Steel O'Connor K
- Subjects
- Adolescent, Adult, Breast Feeding, Female, Humans, Infant, Longitudinal Studies, Mothers, Ontario, Parenting, Young Adult, Diet standards, Feeding Behavior, Infant Food, Infant Nutritional Physiological Phenomena, Nutrition Policy, Public Health
- Abstract
Objective: The current study investigates (i) the extent to which breast-feeding and non-breast-feeding mothers follow the Canadian Nutrition for Healthy Term Infants (NHTI) recommendations; (ii) the first complementary foods given and the differences by breast-feeding status; (iii) whether any breast-feeding is associated with earlier introduction to complementary foods relative to non-breast-feeding, after controlling for potentially confounding factors; and (iv) the need for improvements in timing and resources of interventions by examining breast-feeding rates over time and information sources used by mothers., Design: Longitudinal data from the Kingston, Frontenac, and Lennox & Addington (KFL&A) Infant Feeding Survey were used. Mothers completed a survey at the end of their hospital stay and were interviewed by telephone at 2, 4, 6 and 12 months thereafter., Setting: The study took place in the KFL&A region of Ontario, Canada., Subjects: The sample consisted of 325 mothers who gave birth to a live infant of at least 36 weeks' gestation and a birth weight of at least 1500 g at Kingston General Hospital between January and July of 2008., Results: Four in five mothers introduced complementary foods prior to 6 months. Mothers not breast-feeding at 6 months introduced water, juice, infant cereals, fruit and vegetables, and foods not recommended by Canada's Food Guide sooner than breast-feeding mothers. Breast-feeding mothers were more likely to introduce milks appropriately, but had low adherence to giving their infants vitamin D supplements., Conclusions: To support adherence to NHTI recommendations, interventions should be conducted during early infancy and deliver consistent, evidence-based recommendations.
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- 2016
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49. Searching for Dark Matter Annihilation from Milky Way Dwarf Spheroidal Galaxies with Six Years of Fermi Large Area Telescope Data.
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Ackermann M, Albert A, Anderson B, Atwood WB, Baldini L, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Bissaldi E, Blandford RD, Bloom ED, Bonino R, Bottacini E, Brandt TJ, Bregeon J, Bruel P, Buehler R, Caliandro GA, Cameron RA, Caputo R, Caragiulo M, Caraveo PA, Cecchi C, Charles E, Chekhtman A, Chiang J, Chiaro G, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cuoco A, Cutini S, D'Ammando F, de Angelis A, de Palma F, Desiante R, Digel SW, Di Venere L, Drell PS, Drlica-Wagner A, Essig R, Favuzzi C, Fegan SJ, Ferrara EC, Focke WB, Franckowiak A, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Gomez-Vargas GA, Grenier IA, Guiriec S, Gustafsson M, Hays E, Hewitt JW, Horan D, Jogler T, Jóhannesson G, Kuss M, Larsson S, Latronico L, Li J, Li L, Llena Garde M, Longo F, Loparco F, Lubrano P, Malyshev D, Mayer M, Mazziotta MN, McEnery JE, Meyer M, Michelson PF, Mizuno T, Moiseev AA, Monzani ME, Morselli A, Murgia S, Nuss E, Ohsugi T, Orienti M, Orlando E, Ormes JF, Paneque D, Perkins JS, Pesce-Rollins M, Piron F, Pivato G, Porter TA, Rainò S, Rando R, Razzano M, Reimer A, Reimer O, Ritz S, Sánchez-Conde M, Schulz A, Sehgal N, Sgrò C, Siskind EJ, Spada F, Spandre G, Spinelli P, Strigari L, Tajima H, Takahashi H, Thayer JB, Tibaldo L, Torres DF, Troja E, Vianello G, Werner M, Winer BL, Wood KS, Wood M, Zaharijas G, and Zimmer S
- Abstract
The dwarf spheroidal satellite galaxies (dSphs) of the Milky Way are some of the most dark matter (DM) dominated objects known. We report on γ-ray observations of Milky Way dSphs based on six years of Fermi Large Area Telescope data processed with the new Pass8 event-level analysis. None of the dSphs are significantly detected in γ rays, and we present upper limits on the DM annihilation cross section from a combined analysis of 15 dSphs. These constraints are among the strongest and most robust to date and lie below the canonical thermal relic cross section for DM of mass ≲100 GeV annihilating via quark and τ-lepton channels.
- Published
- 2015
- Full Text
- View/download PDF
50. Cross Sections for the Exclusive Photon Electroproduction on the Proton and Generalized Parton Distributions.
- Author
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Jo HS, Girod FX, Avakian H, Burkert VD, Garçon M, Guidal M, Kubarovsky V, Niccolai S, Stoler P, Adhikari KP, Adikaram D, Amaryan MJ, Anderson MD, Anefalos Pereira S, Ball J, Baltzell NA, Battaglieri M, Batourine V, Bedlinskiy I, Biselli AS, Boiarinov S, Briscoe WJ, Brooks WK, Carman DS, Celentano A, Chandavar S, Charles G, Colaneri L, Cole PL, Compton N, Contalbrigo M, Crede V, D'Angelo A, Dashyan N, De Vita R, De Sanctis E, Deur A, Djalali C, Dupre R, Alaoui AE, Fassi LE, Elouadrhiri L, Fedotov G, Fegan S, Filippi A, Fleming JA, Garillon B, Gevorgyan N, Ghandilyan Y, Gilfoyle GP, Giovanetti KL, Goetz JT, Golovatch E, Gothe RW, Griffioen KA, Guegan B, Guler N, Guo L, Hafidi K, Hakobyan H, Harrison N, Hattawy M, Hicks K, Hirlinger Saylor N, Ho D, Holtrop M, Hughes SM, Ilieva Y, Ireland DG, Ishkhanov BS, Jenkins D, Joo K, Joosten S, Keller D, Khachatryan G, Khandaker M, Kim A, Kim W, Klein A, Klein FJ, Kuhn SE, Kuleshov SV, Lenisa P, Livingston K, Lu HY, MacGregor IJ, McKinnon B, Meziani ZE, Mirazita M, Mokeev V, Montgomery RA, Moutarde H, Movsisyan A, Munevar E, Munoz Camacho C, Nadel-Turonski P, Net LA, Niculescu G, Osipenko M, Ostrovidov AI, Paolone M, Park K, Pasyuk E, Phillips JJ, Pisano S, Pogorelko O, Price JW, Procureur S, Prok Y, Puckett AJ, Raue BA, Ripani M, Rizzo A, Rosner G, Rossi P, Roy P, Sabatié F, Salgado C, Schott D, Schumacher RA, Seder E, Simonyan A, Skorodumina Iu, Smith GD, Sokhan D, Sparveris N, Stepanyan S, Strakovsky II, Strauch S, Sytnik V, Tian Y, Tkachenko S, Ungaro M, Voskanyan H, Voutier E, Walford NK, Watts DP, Wei X, Weinstein LB, Wood MH, Zachariou N, Zana L, Zhang J, Zhao ZW, and Zonta I
- Abstract
Unpolarized and beam-polarized fourfold cross sections (d^{4}σ/dQ^{2}dx_{B}dtdϕ) for the ep→e^{'}p^{'}γ reaction were measured using the CLAS detector and the 5.75-GeV polarized electron beam of the Jefferson Lab accelerator, for 110 (Q^{2},x_{B},t) bins over the widest phase space ever explored in the valence-quark region. Several models of generalized parton distributions (GPDs) describe the data well at most of our kinematics. This increases our confidence that we understand the GPD H, expected to be the dominant contributor to these observables. Through a leading-twist extraction of Compton form factors, these results support the model predictions of a larger nucleon size at lower quark-momentum fraction x_{B}.
- Published
- 2015
- Full Text
- View/download PDF
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