摘要:
The decay E-b -> A0bx-- is observed using a proton-proton collision data sample collected at center-of-ffiffimass energy p s 1/4 13 TeV with the LHCb detector, corresponding to an integrated luminosity of 5.5 fb-1. This process is mediated by the s -> uu over bar d quark-level transition, where the b quark in the E-b baryon is a spectator in the decay. Averaging the results obtained using the two A0b decay modes, A0b -> A thorn c x-- and A0b -> A thorn c x--x- thorn x--, the relative production ratio is measured to be ofE-b =fA0b thorn BoE-b -> A0bx-- thorn 1/4 o7.3 ⠂ 0.8 ⠂ 0.6 thorn x 10-4. Here the uncertainties are statistical and systematic, respectively, and fE-bofA0b thorn is the fragmentation fraction for a b quark into a E-b (A0b) baryon. Using an independent measurement of fE-b =fA0b, the branching fraction BoE-b -> A0bx-- thorn 1/4 o0.89 ⠂ 0.10 ⠂ 0.07 ⠂ 0.29 thorn % is obtained, where the last uncertainty is due to the assumed SU(3) flavor symmetry in the determination of fE-b =fA0b.
作者:
Aaij, R.;Abdelmotteleb, A. S. W.;Beteta, C. Abellan;Abudinen, F.;Ackernley, T.;...
期刊:
Journal of High Energy Physics,2023年2023(9):1-29 ISSN:1029-8479
通讯作者:
Aaij, R
作者机构:
[Ketel, T.; Tuning, N.; Mauri, A.; Usachov, A.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Veronesi, M.; Akiba, K.; Aaij, R.; Aaij, R; Snoch, A.; Biolchini, A.; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; Butter, J. S.; Koppenburg, P.; Soares, M. Senghi; Klaver, S.; Gras, C. Sanchez; Raven, G.; Sole, S. Ferreres; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subat Phys, Amsterdam, Netherlands.;[Da Graca, U. De Freitas Carneiro; Massafferri, A.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; Torres, M. Cruz; Machado, D. Torres; Gomes, A.; dos Reis, A. C.; Leite, J. Baptista de Souza] CBPF, Rio De Janeiro, Brazil.;[De Paula, B. Souza; Lopes, J. H.; Goicochea, J. M. Otalora; Polycarpo, E.; Gandelman, M.; Rangel, M. S.; Hicheur, A.; Gomes, A.; Garcia, L. Meyer; Rodrigues, F. Ferreira; De Paula, L.; Nasteva, I.; Amato, S.; De Almeida, F. L. Souza] Univ Fed Rio de Janeiro, Rio de Janeiro, Brazil.;[Wang, Z.; Qu, S.; Qin, N.; Ren, Z.; Xu, L.; Tou, D. Y.; Wang, J.; Li, A.; Hu, X.; Tan, Y.; Gu, C.; Gong, G.; Kang, Y.; Qi, H. R.; Chen, C.; Zhu, X.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.; Gan, Y.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Sheng, S.; Li, T.; Wang, J.; Chen, S.; Tobin, M.; Miao, D.; Jiang, X.; Batsukh, B.; Zou, Q.; Liu, S.] Inst High Energy Phys, Beijing, Peoples R China.
关键词:
Hadron-Hadron Scattering;Particle Correlations and Fluctuations;QCD
摘要:
Correlations of same-sign charged pions are analysed using proton-lead collision data collected by the LHCb experiment at a nucleon-nucleon centre-of-mass energy of 5.02 TeV, corresponding to an integrated luminosity of 1.06 nb−1. Bose-Einstein correlations are observed in the form of an enhancement of pair production for same-sign charged pions with a small four-momentum difference. The dependence of the correlation radius and the intercept parameter on the reconstructed charged-particle multiplicity is investigated. The measured correlation radii scale linearly with the cube root of the reconstructed charged-particle multiplicity, being compatible with predictions of hydrodynamic models on the collision system evolution.
作者:
Aaij, R.;Abdelmotteleb, A. S. W.;Beteta, C. Abellan;Abudinen, F.;Ackernley, T.;...
期刊:
Journal of High Energy Physics,2023年2023(10):1-8 ISSN:1029-8479
通讯作者:
Belyaev, I
作者机构:
[Ketel, T.; Tuning, N.; Usachov, A.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Veronesi, M.; Akiba, K.; Aaij, R.; Snoch, A.; Biolchini, A.; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; van Veghel, M.; Butter, J. S.; Koppenburg, P.; Soares, M. Senghi; Klaver, S.; Gras, C. Sanchez; Raven, G.; Sole, S. Ferreres; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subat Phys, Amsterdam, Netherlands.;[Da Graca, U. De Freitas Carneiro; Baptista de Souza Leite, J.; Massafferri, A.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; Torres, M. Cruz; Machado, D. Torres; Gomes, A.; dos Reis, A. C.; Santoro, L.] CBPF, Rio De Janeiro, Brazil.;[De Paula, B. Souza; Lopes, J. H.; Goicochea, J. M. Otalora; Polycarpo, E.; Gandelman, M.; Rangel, M. S.; Hicheur, A.; Gomes, A.; Garcia, L. Meyer; Rodrigues, F. Ferreira; De Paula, L.; Nasteva, I.; Amato, S.; De Almeida, F. L. Souza] Univ Fed Rio de Janeiro, Rio de Janeiro, Brazil.;[Wang, Z.; Qu, S.; Qin, N.; Ren, Z.; Xu, L.; Tou, D. Y.; Wang, J.; Li, A.; Hu, X.; Tan, Y.; Gu, C.; Gong, G.; Kang, Y.; Qi, H. R.; Zhu, X.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Sheng, S.; Li, T.; Wang, J.; Chen, S.; Tobin, M.; Miao, D.; Jiang, X.; Batsukh, B.; Zou, Q.; Liu, S.] IHEP, Beijing, Peoples R China.
通讯机构:
[Belyaev, I ] C;CERN, Geneva, Switzerland.
关键词:
B Physics;Branching fraction;Charm Physics;Hadron-Hadron Scattering
摘要:
The B+ → Jψη′K+ decay is observed for the first time using proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7, 8, and 13 TeV, corresponding to a total integrated luminosity of 9 fb−1. The branching fraction of this decay is measured relative to the known branching fraction of the B+ → ψ(2S)K+ decay and found to beBB+→Jψη′K+BB+→ψ2SK+=4.91±0.47±0.29±0.07×10−2,\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \frac{\mathcal{B}\left({B}^{+}\to {J\psi \eta}^{\prime }{K}^{+}\right)}{\mathcal{B}\left({B}^{+}\to \psi (2S){K}^{+}\right)}=\left(4.91\pm 0.47\pm 0.29\pm 0.07\right)\times {10}^{-2}, $$\end{document}where the first uncertainty is statistical, the second is systematic and the third is related to external branching fractions. A first look at the J/ψη′ mass distribution is performed and no signal of intermediate resonances is observed.
作者机构:
[Ketel, T.; Tuning, N.; Mauri, A.; Usachov, A.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Veronesi, M.; Akiba, K.; Aaij, R.; Snoch, A.; van Beuzekom, M.; Biolchini, A.; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; Butter, J. S.; Koppenburg, P.; Soares, M. Senghi; Klaver, S.; Gras, C. Sanchez; Raven, G.; Sole, S. Ferreres; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subat Phys, Amsterdam, Netherlands.;[Baptista de Souza Leite, J.; De Freitas Carneiro Da Graca, U.; Massafferri, A.; Cruz Torres, M.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; Leite, JBD; Gomes, A.; Torres Machado, D.; dos Reis, A. C.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil.;[Lopes, J. H.; Polycarpo, E.; Souza De Paula, B.; Souza De Almeida, F. L.; Gandelman, M.; Rangel, M. S.; Ferreira Rodrigues, F.; Hicheur, A.; Otalora Goicochea, J. M.; De Paula, L.; Nasteva, I.; Amato, S.; Meyer Garcia, L.] Univ Fed Rio de Janeiro, Rio De Janeiro, Brazil.;[Wang, Z.; Ren, Z.; Xu, L.; Tou, D. Y.; Wang, J.; Li, A.; Hu, X.; Tan, Y.; Gu, C.; Gong, G.; Kang, Y.; Qi, H. R.; Chen, C.; Zhu, X.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.; Gan, Y.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Ma, L.; Sheng, S.; Li, T.; Wang, J.; Chen, S.; Tobin, M.; Miao, D.; Grieser, N. A.; Jiang, X.; Batsukh, B.; Zou, Q.; Liu, S.] Inst High Energy Phys, Beijing, Peoples R China.
通讯机构:
[Leite, JBD ] C;Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil.
摘要:
The branching fraction of the rare decay Lambda(0 )(b)-> Lambda(1520)mu(+)mu(-) is measured for the first time, in the squared dimuon mass intervals q(2), excluding the J/psi and psi(2S) regions. The data sample analyzed was collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to a total integrated luminosity of 9 fb(-1). The result in the highest q(2) interval, q(2) > 15.0 GeV2/c(4), where theoretical predictions have the smallest model dependence, agrees with the predictions.
作者机构:
[Ketel, T.; Tuning, N.; Usachov, A.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Veronesi, M.; Akiba, K.; Aaij, R.; Aaij, R; Snoch, A.; Biolchini, A.; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; van Veghel, M.; Butter, J. S.; Koppenburg, P.; Soares, M. Senghi; Klaver, S.; Gras, C. Sanchez; Raven, G.; Sole, S. Ferreres; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subat Phys, Amsterdam, Netherlands.;[Baptista de Souza Leite, J.; De Freitas Carneiro Da Graca, U.; Massafferri, A.; Cruz Torres, M.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; Gomes, A.; Torres Machado, D.; dos Reis, A. C.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil.;[Lopes, J. H.; Polycarpo, E.; Souza De Paula, B.; Souza De Almeida, F. L.; Gandelman, M.; Rangel, M. S.; Ferreira Rodrigues, F.; Hicheur, A.; Otalora Goicochea, J. M.; Gomes, A.; De Paula, L.; Nasteva, I.; Amato, S.; Meyer Garcia, L.] Univ Fed Rio de Janeiro, Rio De Janeiro, Brazil.;[Wang, Z.; Qu, S.; Qin, N.; Ren, Z.; Xu, L.; Tou, D. Y.; Wang, J.; Li, A.; Hu, X.; Tan, Y.; Gu, C.; Gong, G.; Kang, Y.; Qi, H. R.; Zhu, X.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Sheng, S.; Li, T.; Wang, J.; Chen, S.; Tobin, M.; Miao, D.; Jiang, X.; Batsukh, B.; Zou, Q.; Liu, S.] Inst High Energy Phys IHEP, Beijing, Peoples R China.
摘要:
The ratios of branching fractions R(D^{*})≡B(B[over ¯]→D^{*}τ^{-}ν[over ¯]_{τ})/B(B[over ¯]→D^{*}μ^{-}ν[over ¯]_{μ}) and R(D^{0})≡B(B^{-}→D^{0}τ^{-}ν[over ¯]_{τ})/B(B^{-}→D^{0}μ^{-}ν[over ¯]_{μ}) are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0 fb^{-1} of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode τ^{-}→μ^{-}ν_{τ}ν[over ¯]_{μ}. The measured values are R(D^{*})=0.281±0.018±0.024 and R(D^{0})=0.441±0.060±0.066, where the first uncertainty is statistical and the second is systematic. The correlation between these measurements is ρ=-0.43. The results are consistent with the current average of these quantities and are at a combined 1.9 standard deviations from the predictions based on lepton flavor universality in the standard model.
作者:
Aaij, R.;Abdelmotteleb, A. S. W.;Beteta, C. Abellan;Abudinen, F.;Ackernley, T.;...
期刊:
PHYSICAL REVIEW D,2023年108(1) ISSN:2470-0010
通讯作者:
Leite, JBD
作者机构:
[Ketel, T.; Tuning, N.; Mauri, A.; Usachov, A.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Veronesi, M.; Akiba, K.; Aaij, R.; Snoch, A.; van Beuzekom, M.; Biolchini, A.; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; Butter, J. S.; Koppenburg, P.; Soares, M. Senghi; Klaver, S.; Gras, C. Sanchez; Raven, G.; Sole, S. Ferreres; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subat Phys, Amsterdam, Netherlands.;[Baptista de Souza Leite, J.; De Freitas Carneiro Da Graca, U.; Massafferri, A.; Cruz Torres, M.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; Leite, JBD; Gomes, A.; Torres Machado, D.; dos Reis, A. C.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil.;[Lopes, J. H.; Polycarpo, E.; Souza De Paula, B.; Souza De Almeida, F. L.; Gandelman, M.; Rangel, M. S.; Ferreira Rodrigues, F.; Hicheur, A.; Otalora Goicochea, J. M.; De Paula, L.; Nasteva, I.; Amato, S.; Meyer Garcia, L.] Univ Fed Rio de Janeiro, Rio De Janeiro, Brazil.;[Wang, Z.; Qu, S.; Qin, N.; Ren, Z.; Xu, L.; Tou, D. Y.; Wang, J.; Li, A.; Hu, X.; Tan, Y.; Gu, C.; Gong, G.; Kang, Y.; Qi, H. R.; Chen, C.; Zhu, X.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.; Gan, Y.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Ma, L.; Sheng, S.; Li, T.; Wang, J.; Chen, S.; Tobin, M.; Miao, D.; Grieser, N. A.; Jiang, X.; Batsukh, B.; Zou, Q.; Liu, S.] Inst High Energy Phys, Beijing, Peoples R China.
通讯机构:
[Leite, JBD ] C;Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil.
摘要:
Resonant structures in the dipion mass spectrum from & chi;c1(3872) & RARR; & pi;+& pi;-J=& psi; decays, produced via B+ & RARR; K+& chi;c1(3872) decays, are analyzed using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb-1. A sizeable contribution from the isospin conserving & chi;c1(3872) & RARR; & omega;J=& psi; decay is established for the first time, (21.4 & PLUSMN; 2.3 & PLUSMN; 2.0)%, with a significance of more than 7.1 & sigma;. The amplitude of isospin violating decay, & chi;c1(3872) & RARR; & rho;0J=& psi;, relative to isospin conserving decay, & chi;c1(3872) & RARR; & omega;J=& psi;, is properly determined, and it is a factor of 6 larger than expected for a pure charmonium state.
作者:
Aaij, R.;Abdelmotteleb, A. S. W.;Beteta, C. Abellan;Abudinen, F.;Ackernley, T.;...
期刊:
EUROPEAN PHYSICAL JOURNAL C,2023年83(8):1-7 ISSN:1434-6044
通讯作者:
Aaij, R
作者机构:
[Ketel, T.; Tuning, N.; Mauri, A.; Usachov, A.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Veronesi, M.; Akiba, K.; Aaij, R.; Aaij, R; Snoch, A.; Biolchini, A.; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; Butter, J. S.; Koppenburg, P.; Soares, M. Senghi; Klaver, S.; Gras, C. Sanchez; Raven, G.; Sole, S. Ferreres; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subat Phys, Amsterdam, Netherlands.;[Da Graca, U. De Freitas Carneiro; Massafferri, A.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; Torres, M. Cruz; Machado, D. Torres; Gomes, A.; dos Reis, A. C.; Leite, J. Baptista de Souza] CBPF, Rio De Janeiro, Brazil.;[De Paula, B. Souza; Lopes, J. H.; Goicochea, J. M. Otalora; Polycarpo, E.; Gandelman, M.; Rangel, M. S.; Hicheur, A.; Gomes, A.; Garcia, L. Meyer; Rodrigues, F. Ferreira; De Paula, L.; Nasteva, I.; Amato, S.; De Almeida, F. L. Souza] Univ Fed Rio de Janeiro, Rio de Janeiro, Brazil.;[Wang, Z.; Qu, S.; Qin, N.; Ren, Z.; Xu, L.; Tou, D. Y.; Wang, J.; Li, A.; Hu, X.; Tan, Y.; Gu, C.; Gong, G.; Kang, Y.; Qi, H. R.; Chen, C.; Zhu, X.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.; Gan, Y.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Sheng, S.; Li, T.; Wang, J.; Chen, S.; Tobin, M.; Miao, D.; Jiang, X.; Batsukh, B.; Zou, Q.; Liu, S.] Inst High Energy Phys, Beijing, Peoples R China.
作者机构:
[Ketel, T.; Tuning, N.; Mauri, A.; Usachov, A.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Veronesi, M.; Akiba, K.; Aaij, R.; Snoch, A.; van Beuzekom, M.; Biolchini, A.; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; Butter, J. S.; Koppenburg, P.; Soares, M. Senghi; Klaver, S.; Gras, C. Sanchez; Raven, G.; Sole, S. Ferreres; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subat Phys, Amsterdam, Netherlands.;[Baptista de Souza Leite, J.; De Freitas Carneiro Da Graca, U.; Massafferri, A.; Cruz Torres, M.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; Leite, JBD; Gomes, A.; Torres Machado, D.; dos Reis, A. C.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil.;[Lopes, J. H.; Polycarpo, E.; Souza De Paula, B.; Souza De Almeida, F. L.; Gandelman, M.; Rangel, M. S.; Ferreira Rodrigues, F.; Hicheur, A.; Otalora Goicochea, J. M.; De Paula, L.; Nasteva, I.; Amato, S.; Meyer Garcia, L.] Univ Fed Rio de Janeiro, Rio De Janeiro, Brazil.;[Wang, Z.; Qu, S.; Qin, N.; Ren, Z.; Xu, L.; Tou, D. Y.; Wang, J.; Li, A.; Hu, X.; Tan, Y.; Gu, C.; Gong, G.; Kang, Y.; Qi, H. R.; Chen, C.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.; Gan, Y.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Ma, L.; Sheng, S.; Li, T.; Xu, L.; Wang, J.; Chen, S.; Tobin, M.; Miao, D.; Grieser, N. A.; Jiang, X.; Batsukh, B.; Zou, Q.; Liu, S.] Inst High Energy Phys, Beijing, Peoples R China.
通讯机构:
[Leite, JBD ] C;Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil.
摘要:
Searches for the rare hadronic decays B-0 -> p (p) over barp (p) over bar and B-s(0) -> p (p) over barp (p) over bar are performed using proton-proton collision data recorded by the LHCb experiment and corresponding to an integrated luminosity of 9 fb-1. Significances of 9.3 sigma and 4.0 sigma, including statistical and systematic uncertainties, are obtained for the B-0 -> p (p) over barp (p) over bar and B-s(0) -> p (p) over barp (p) over bar signals, respectively. The branching fractions are measured relative to the topologically similar normalization decays B-0 -> J/psi(-> p (p) over bar )K*(0)(-> K+ pi(-) ) and B-s(0) -> J/psi(-> p (p) over bar )X phi(-> K+ K- ). The branching fractions are measured to be B(B-0 -> p (p) over barp (p) over bar) = (2.2 +/- 0.4 +/- 0.1 +/- 0.1) x 10(-8) and B(B-s(0) -> p (p) over barp (p) over bar) = (2.3 +/- 1.0 +/- 0.2 +/- 0.1) x 10(-8). In these measurements, the first uncertainty is statistical, the second is systematic, and the third one is due to the external branching fraction of the normalization channel.
作者:
Aaij, R.;Abdelmotteleb, A. S. W.;Beteta, C. Abellan;Abudinen, F.;Ackernley, T.;...
期刊:
Journal of High Energy Physics,2023年2023(7) ISSN:1029-8479
通讯作者:
Aaij, R
作者机构:
[Ketel, T.; Tuning, N.; Mauri, A.; Usachov, A.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Veronesi, M.; Akiba, K.; Aaij, R.; Aaij, R; Snoch, A.; Biolchini, A.; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; Butter, J. S.; Koppenburg, P.; Soares, M. Senghi; Klaver, S.; Gras, C. Sanchez; Raven, G.; Sole, S. Ferreres; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subat Phys, Amsterdam, Netherlands.;[Da Graca, U. De Freitas Carneiro; Massafferri, A.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; Torres, M. Cruz; Machado, D. Torres; Gomes, A.; dos Reis, A. C.; Leite, J. Baptista de Souza] CBPF, Rio De Janeiro, Brazil.;[De Paula, B. Souza; Lopes, J. H.; Goicochea, J. M. Otalora; Polycarpo, E.; Gandelman, M.; Rangel, M. S.; Hicheur, A.; Gomes, A.; Garcia, L. Meyer; Rodrigues, F. Ferreira; De Paula, L.; Nasteva, I.; Amato, S.; De Almeida, F. L. Souza] Univ Fed Rio de Janeiro, Rio de Janeiro, Brazil.;[Wang, Z.; Qu, S.; Qin, N.; Ren, Z.; Xu, L.; Tou, D. Y.; Wang, J.; Li, A.; Hu, X.; Tan, Y.; Gu, C.; Gong, G.; Kang, Y.; Qi, H. R.; Chen, C.; Zhu, X.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.; Gan, Y.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Sheng, S.; Li, T.; Wang, J.; Chen, S.; Tobin, M.; Miao, D.; Jiang, X.; Batsukh, B.; Zou, Q.; Liu, S.] Inst High Energy Phys, Beijing, Peoples R China.
关键词:
B Physics;Branching fraction;Flavour Physics;Hadron-Hadron Scattering
摘要:
The first observation of the Λb0→Ds−p\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\Lambda}_b^0\to {D}_s^{-}p $$\end{document} decay is presented using proton-proton collision data collected by the LHCb experiment at a centre-of-mass energy of s\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \sqrt{s} $$\end{document} = 13 TeV, corresponding to a total integrated luminosity of 6 fb−1. Using the Λb0→Λc+π−\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\Lambda}_b^0\to {\Lambda}_c^{+}{\pi}^{-} $$\end{document} decay as the normalisation mode, the branching fraction of the Λb0→Ds−p\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\Lambda}_b^0\to {D}_s^{-}p $$\end{document} decay is measured to be BΛb0→Ds−p=12.6±0.5±0.3±1.2×10−6\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \mathcal{B}\left({\Lambda}_b^0\to {D}_s^{-}p\right)=\left(12.6\pm 0.5\pm 0.3\pm 1.2\right)\times {10}^{-6} $$\end{document}, where the first uncertainty is statistical, the second systematic and the third due to uncertainties in the branching fractions of the Λb0→Λc+π−\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\Lambda}_b^0\to {\Lambda}_c^{+}{\pi}^{-} $$\end{document}, Ds−→K−K+π−\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {D}_s^{-}\to {K}^{-}{K}^{+}{\pi}^{-} $$\end{document} and Λc+→pK−π+\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\Lambda}_c^{+}\to p{K}^{-}{\pi}^{+} $$\end{document} decays.
作者机构:
[Ketel, T.; Mulder, M.; Tuning, N.; Perez, D. H. Campora; Mauri, A.; Usachov, A.; de Vries, J. A.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Sanchez Gras, C.; Veronesi, M.; Akiba, K.; Aaij, R.; Aaij, R; Snoch, A.; De Bruyn, K.; van Beuzekom, M.; Biolchini, A.; Martinez, M. Lucio; Jans, E.; Vos, K.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Grecu, A. T.; Merk, M.; Onderwater, C. J. G.; Bolognani, C. S.; van Veghel, M.; Butter, J. S.; Koppenburg, P.; Pawley, C. J.; Soares, M. Senghi; Klaver, S.; Raven, G.; Sole, S. Ferreres; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subatom Phys, Amsterdam, Netherlands.;[Massafferri, A.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; de Souza Leite, J. Baptista; Torres, M. Cruz; Machado, D. Torres; Gomes, A.; Carneiro Da Graca, U. De Freitas; dos Reis, A. C.; Santovetti, E.] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil.;[De Paula, B. Souza; Lopes, J. H.; Polycarpo, E.; Souza De Almeida, F. L.; Gandelman, M.; Gobel, C.; Rangel, M. S.; Hicheur, A.; Otalora Goicochea, J. M.; Garcia, L. Meyer; Rodrigues, F. Ferreira; De Paula, L.; Nasteva, I.; Amato, S.] Univ Fed Rio De Janeiro UFRJ, Rio De Janeiro, Brazil.;[Cai, H.; Bian, L.; Liu, G.; Qu, S.; Qin, N.; Ren, Z.; Xu, L.; Tou, D. Y.; Huang, X.; Li, H.; Li, A.; Hu, X.; Grauges, E.; Tan, Y.; Gu, C.; Gong, G.; Wang, X.; Bursche, A.; Kang, Y.; Fang, B.; Qi, H. R.; Chen, C.; Zhu, X.; Sun, L.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.; Gan, Y.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Ma, L.; Sheng, S.; Chen, S.; Greeven, L. M.; Li, P. -R.; Tobin, M.; Miao, D.; Jiang, X.; Batsukh, B.; Zou, Q.; Liu, S.] Inst High Energy Phys IHEP, Beijing, Peoples R China.
摘要:
A combined amplitude analysis is performed for the decays B0-+ D0D thorn s & pi;- and B thorn -+ D-D thorn s & pi; thorn , which are related by isospin symmetry. The analysis is based on data collected by the LHCb detector in proton -proton collisions at center-of-mass energies of 7, 8, and 13 TeV. The full data sample corresponds to an integrated luminosity of 9 fb-1. Two new resonant states with masses of 2.908 ⠂ 0.011 ⠂ 0.020 GeV and widths of 0.136 ⠂ 0.023 ⠂ 0.013 GeV are observed, which decay to D thorn s & pi; thorn and D thorn s & pi;- respectively. The former state indicates the first observation of a doubly charged open-charm tetraquark state with minimal quark content 1/2cs over bar ud over bar ⠃, and the latter state is a neutral tetraquark composed of 1/2cs over bar u over bar d ⠃ quarks. Both states are found to have spin-parity of 0 thorn , and their resonant parameters are consistent with each other, which suggests that they belong to an isospin triplet.
作者:
Aaij, R.;Abdelmotteleb, A. S. W.;Beteta, C. Abellan;Abudinen, F.;Ackernley, T.;...
期刊:
Journal of High Energy Physics,2023年2023(7):1-35 ISSN:1029-8479
通讯作者:
Leite, JBD
作者机构:
[Ketel, T.; Tuning, N.; Mauri, A.; Usachov, A.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Veronesi, M.; Akiba, K.; Aaij, R.; Snoch, A.; van Beuzekom, M.; Biolchini, A.; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; Butter, J. S.; Koppenburg, P.; Soares, M. Senghi; Klaver, S.; Gras, C. Sanchez; Raven, G.; Sole, S. Ferreres; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subat Phys, Amsterdam, Netherlands.;[Baptista de Souza Leite, J.; De Freitas Carneiro Da Graca, U.; Massafferri, A.; Cruz Torres, M.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; Leite, JBD; Gomes, A.; Torres Machado, D.; dos Reis, A. C.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil.;[Lopes, J. H.; Polycarpo, E.; Souza De Paula, B.; Souza De Almeida, F. L.; Gandelman, M.; Rangel, M. S.; Ferreira Rodrigues, F.; Hicheur, A.; Otalora Goicochea, J. M.; De Paula, L.; Nasteva, I.; Amato, S.; Meyer Garcia, L.] Univ Fed Rio de Janeiro, Rio De Janeiro, Brazil.;[Wang, Z.; Qu, S.; Qin, N.; Ren, Z.; Xu, L.; Tou, D. Y.; Wang, J.; Li, A.; Hu, X.; Tan, Y.; Gu, C.; Gong, G.; Kang, Y.; Qi, H. R.; Chen, C.; Zhu, X.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.; Gan, Y.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Ma, L.; Sheng, S.; Li, T.; Wang, J.; Chen, S.; Tobin, M.; Miao, D.; Grieser, N. A.; Jiang, X.; Batsukh, B.; Zou, Q.; Liu, S.] Inst High Energy Phys, Beijing, Peoples R China.
通讯机构:
[Leite, JBD ] C;Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil.
关键词:
Charm Physics;Hadron-Hadron Scattering;Particle and Resonance Production
摘要:
A Dalitz plot analysis of the Ds+\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {D}_s^{+} $$\end{document} → π−π+π+ decay is presented. The analysis is based on proton-proton collision data recorded by the LHCb experiment at a centre-of-mass energy of 8 TeV and corresponding to an integrated luminosity of 1.5 fb−1. The resonant structure of the decay is obtained using a quasi-model-independent partial-wave analysis, in which the π+π− S-wave amplitude is parameterised as a generic complex function determined by a fit to the data. The S-wave component is found to be dominant, followed by the contribution from spin-2 resonances and a small contribution from spin-1 resonances. The latter includes the first observation of the Ds+\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {D}_s^{+} $$\end{document}→ ω(782)π+ channel in the Ds+\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {D}_s^{+} $$\end{document}→ π−π+π+ decay. The resonant structures of the Ds+\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {D}_s^{+} $$\end{document}→ π−π+π+ and D+→ π−π+π+ decays are compared, providing information about the mechanisms for the hadron formation in these decays.
作者:
Aaij, R.;Abdelmotteleb, A. S. W.;Beteta, C. Abellan;Abudinen, F.;Ackernley, T.;...
期刊:
Journal of High Energy Physics,2023年2023(7) ISSN:1029-8479
通讯作者:
Aaij, R
作者机构:
[Ketel, T.; Tuning, N.; Mauri, A.; Usachov, A.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Veronesi, M.; Akiba, K.; Aaij, R.; Aaij, R; Snoch, A.; Biolchini, A.; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; Butter, J. S.; Koppenburg, P.; Soares, M. Senghi; Klaver, S.; Gras, C. Sanchez; Raven, G.; Sole, S. Ferreres; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subat Phys, Amsterdam, Netherlands.;[Da Graca, U. De Freitas Carneiro; Massafferri, A.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; Torres, M. Cruz; Machado, D. Torres; Gomes, A.; dos Reis, A. C.; Leite, J. Baptista de Souza] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil.;[De Paula, B. Souza; Lopes, J. H.; Polycarpo, E.; Gandelman, M.; Rangel, M. S.; Hicheur, A.; Gomes, A.; Garcia, L. Meyer; Rodrigues, F. Ferreira; De Paula, L.; Nasteva, I.; Amato, S.; Goicochea, M. Otalora; De Almeida, F. L. Souza] Univ Fed Rio de Janeiro, Rio De Janeiro, Brazil.;[Wang, Z.; Qu, S.; Qin, N.; Ren, Z.; Xu, L.; Tou, D. Y.; Wang, J.; Li, A.; Hu, X.; Tan, Y.; Gu, C.; Gong, G.; Kang, Y.; Qi, H. R.; Chen, C.; Zhu, X.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.; Gan, Y.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Sheng, S.; Li, T.; Wang, J.; Chen, S.; Tobin, M.; Miao, D.; Jiang, X.; Batsukh, B.; Zou, Q.; Liu, S.] Inst High Energy Phys, Beijing, Peoples R China.
关键词:
B Physics;Hadron-Hadron Scattering;Quarkonium;Spectroscopy
摘要:
The first observation of the Bs0\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {B}_s^0 $$\end{document}→ (χc1(3872) → J/ψπ+π−)π+π− decay is reported using proton-proton collision data, corresponding to integrated luminosities of 1, 2 and 6 fb−1, collected by the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV, respectively. The ratio of branching fractions relative to the Bs0\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {B}_s^0 $$\end{document}→ (ψ(2S) → J/ψπ+π−)π+π− decay is measured to beBBs0→χc13872π+π−×Bχc13872→J/ψπ+π−BBs0→ψ2Sπ+π−×Bψ2S→J/ψπ+π−=6.8±1.1±0.2×10−2,\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \frac{\mathcal{B}\left({B}_s^0\to {\chi}_{c1}(3872){\pi}^{+}{\pi}^{-}\right)\times \mathcal{B}\left({\chi}_{c1}(3872)\to J/\psi {\pi}^{+}{\pi}^{-}\right)}{\mathcal{B}\left({B}_s^0\to \psi (2S){\pi}^{+}{\pi}^{-}\right)\times \mathcal{B}\left(\psi (2S)\to J/\psi {\pi}^{+}{\pi}^{-}\right)}=\left(6.8\pm 1.1\pm 0.2\right)\times {10}^{-2}, $$\end{document}where the first uncertainty is statistical and the second systematic. The mass spectrum of the π+π− system recoiling against the χc1(3872) meson exhibits a large contribution from Bs0\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {B}_s^0 $$\end{document}→ χc1(3872) (f0(980) → π+π−) decays.
作者:
Aaij, R.;Abdelmotteleb, A. S. W.;Beteta, C. Abellan;Abudinen, F.;Ackernley, T.;...
期刊:
EUROPEAN PHYSICAL JOURNAL C,2023年83(7):1-11 ISSN:1434-6044
通讯作者:
Leite, JBD
作者机构:
[Ketel, T.; Tuning, N.; Mauri, A.; Usachov, A.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Veronesi, M.; Akiba, K.; Aaij, R.; Snoch, A.; van Beuzekom, M.; Biolchini, A.; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; Butter, J. S.; Koppenburg, P.; Soares, M. Senghi; Klaver, S.; Gras, C. Sanchez; Raven, G.; Sole, S. Ferreres; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Nikhef Natl Inst Subat Phys, Amsterdam, Netherlands.;[Baptista de Souza Leite, J.; De Freitas Carneiro Da Graca, U.; Massafferri, A.; Cruz Torres, M.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; Leite, JBD; Gomes, A.; Torres Machado, D.; dos Reis, A. C.] Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil.;[Lopes, J. H.; Polycarpo, E.; Souza De Paula, B.; Souza De Almeida, F. L.; Gandelman, M.; Rangel, M. S.; Ferreira Rodrigues, F.; Hicheur, A.; Otalora Goicochea, J. M.; De Paula, L.; Nasteva, I.; Amato, S.; Meyer Garcia, L.] Univ Fed Rio de Janeiro, Rio De Janeiro, Brazil.;[Wang, Z.; Qu, S.; Qin, N.; Ren, Z.; Xu, L.; Tou, D. Y.; Wang, J.; Li, A.; Hu, X.; Tan, Y.; Gu, C.; Gong, G.; Kang, Y.; Qi, H. R.; Chen, C.; Zhu, X.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.; Gan, Y.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Ma, L.; Sheng, S.; Li, T.; Wang, J.; Chen, S.; Tobin, M.; Miao, D.; Grieser, N. A.; Jiang, X.; Batsukh, B.; Zou, Q.; Liu, S.] Inst High Energy Phys, Beijing, Peoples R China.
作者:
Aaij, R.;Abdelmotteleb, A. S. W.;Beteta, C. Abellan;Abudinen, F.;Ackernley, T.;...
期刊:
EUROPEAN PHYSICAL JOURNAL C,2023年83(6):1-19 ISSN:1434-6044
通讯作者:
Evans, T
作者机构:
[Mulder, M.; Tuning, N.; Mauri, A.; Usachov, A.; Lukashenko, V.; Galati, M. D.; Heijhoff, K.; Veronesi, M.; Akiba, K.; Aaij, R.; Snoch, A.; De Bruyn, K.; van Beuzekom, M.; Biolchini, A.; Jans, E.; Greeven, L. M.; Geertsema, R. E.; Pellegrino, A.; Gabriel, E.; Merk, M.; Onderwater, C. J. G.; van Veghel, M.; Butter, J. S.; Koppenburg, P.; Kostiuk, I.; Schubiger, M.; Hulsbergen, W.] Univ Groningen, Van Swinderen Inst, Groningen, Netherlands.;[Baptista de Souza Leite, J.; De Freitas Carneiro Da Graca, U.; Massafferri, A.; Cruz Torres, M.; De Miranda, J. M.; Falcao, L. N.; Bediaga, I. B.; Gomes, A.; Torres Machado, D.; dos Reis, A. C.] Ctr Brasileiro Pesquisas Fis CBPF, Rio De Janeiro, Brazil.;[Lopes, J. H.; Polycarpo, E.; Souza De Paula, B.; Souza De Almeida, F. L.; Gandelman, M.; Rangel, M. S.; Ferreira Rodrigues, F.; Hicheur, A.; Otalora Goicochea, J. M.; Garcia, L. Meyer; De Paula, L.; Nasteva, I.; Amato, S.] Univ Fed Rio Janeiro UFRJ, Rio De Janeiro, Brazil.;[Wang, Z.; Qu, S.; Qin, N.; Ren, Z.; Xu, L.; Tou, D. Y.; Wang, J.; Li, A.; Hu, X.; Tan, Y.; Gu, C.; Gong, G.; Kang, Y.; Qi, H. R.; Chen, C.; Zhu, X.; Luo, Y.; Yang, D.; Mu, H.; Zeng, M.; Dong, C.; Zhang, L.; Gan, Y.] Tsinghua Univ, Ctr High Energy Phys, Beijing, Peoples R China.;[Lu, Y.; Li, Y.; Ma, L.; Sheng, S.; Wang, J.; Chen, S.; Tobin, M.; Miao, D.; Grieser, N. A.; Jiang, X.; Batsukh, B.; Zou, Q.; Liu, S.; Carli, I.] Inst High Energy Phys IHEP, Beijing, Peoples R China.
摘要:
The interpretation of cosmic antiproton flux measurements from space-borne experiments is currently limited by the knowledge of the antiproton production cross-section in collisions between primary cosmic rays and the interstellar medium. Using collisions of protons with an energy of 6.5TeV\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\,\text {Te\hspace{-1.00006pt}V}$$\end{document} incident on helium nuclei at rest in the proximity of the interaction region of the LHCb experiment, the ratio of antiprotons originating from antihyperon decays to prompt production is measured for antiproton momenta between 12 and 110GeV\!/c\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$110\,\text {Ge\hspace{-1.00006pt}V\!/}c $$\end{document}. The dominant antihyperon contribution, namely Λ¯→p¯π+\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\overline{\varLambda }} \rightarrow {\overline{{p}}} {{\pi } ^+} $$\end{document} decays from promptly produced Λ¯\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\overline{\varLambda }$$\end{document} particles, is also exclusively measured. The results complement the measurement of prompt antiproton production obtained from the same data sample. At the energy scale of this measurement, the antihyperon contributions to antiproton production are observed to be significantly larger than predictions of commonly used hadronic production models.
摘要:
This study presents an electronics system for cosmic X-ray polarization detection (CXPD). The CXPD was designed as a high-sensitivity soft X-ray polarimeter with a measurement energy range of 2–10 keV carried by a CubeSat. A stable and functionally complete electronics system under power and space constraints is a key challenge. The complete CXPD electronics system (CXPDES) comprises hardware and firmware. CXPDES adopts a three-layer electronic board structure based on functionality and available space. Two gas pixel detectors (GPDs) were placed on the top layer board, and CXPDES provided the GPDs with voltages up to
$$-$$
4000V. Each GPD signal was digitized, compressed, encoded, and stored before being transmitted to the ground. The CXPDES provided stable and high-speed communication based on a scheme that separated command and data transmission, and it supports the CXPDES in-orbit upgrade. In addition, environmental monitors, silicon photomultiplier (SiPM) triggers, power management, GPDs configuration, and mode switches were included in the overall operating logic of the CXPDES. The results obtained by testing the CXPDES showed that it satisfied all the requirements of CXPD. The CXPDES provides design experience and technological readiness for future large-area X-ray polarimetry missions.
作者机构:
[Xu, Hongbo; Zhu, Li; Li, Ruijie; Chen, Yun; Zhang, Guoping] Cent China Normal Univ, Coll Phys Sci & Technol, Wuhan 430079, Peoples R China.;[Zhu, Li] Hubei Minzu Univ, Coll Intelligent Syst Sci & Engn, Enshi 445000, Peoples R China.
通讯机构:
[Zhang, GP ] C;Cent China Normal Univ, Coll Phys Sci & Technol, Wuhan 430079, Peoples R China.
摘要:
Intelligent reflective surface (IRS) and unmanned aerial vehicle (UAV) communication are two key technologies in the sixth generation of mobile communication (6G). In this paper, IRS is equipped on UAV to form aerial IRS, which can achieve 360° panoramic full-angle reflection and flexible deployment of IRS. In order to achieve high-quality and ubiquitous network coverage under data privacy and low latency requirements, we propose an Federated learning (FL) network via Over-the-Air computation (AirComp) in IRS-assisted UAV communications. Our goal is to minimize the worst-case mean square error (MSE) by jointly optimizing the IRS phase shift, denoising factor for noise suppression, the user's transmission power, and UAV trajectory. Optimizing and quickly adjusting the UAV position and IRS phase shift, it flexibly assists the signal transmission between users and base stations (BS). In order to solve this complex non-convex problem, we propose a low-complexity iterative algorithm, which divides the original problem into four sub-problems, respectively using the semi-definite programming (SDP) method, slack variable introduction method, successive convex approximation (SCA) method to solve each sub-problem. Through the analysis of simulation results, our proposed design scheme is obviously better than other benchmark schemes.
摘要:
Herein, we aimed to solve the problem of difficulty in filtering the noise components in the monitoring of strain on wind turbine blades using fiber bragg grating, a denoising method based on parameter-optimized variational mode decomposition (VMD) is proposed. This method uses the minimum envelope entropy as the fitness function and the slime mould algorithm for self-adaptive optimization to find the optimal combination of modal decomposition components K and the quadratic penalty factor alpha of VMD. The optimized VMD was used to decompose the strain data of wind turbine blades over time into K intrinsic mode components, and the noise mode was removed using the sample entropy to obtain the effective signal. The proposed method was compared to ensemble empirical mode decomposition and complementary ensemble empirical mode decomposition using the simulated signals and engineering data. The experimental results show that the proposed method can effectively remove noise from the strain data of wind turbine blades and has better denoising performance than the other two methods, which provides a reliable basis for analyzing the strain data of wind turbine blades.
摘要:
We report the discovery of PSR J1909+0122 by the Five-hundred-meter Aperture Spherical Radio Telescope (FAST) as part of the Commensal Radio Astronomy FAST Survey. PSR J1909+0122 has a spin period of 1.257 s and a dispersion measure of 186.2 pc cm−3. The averaged pulse profile shows two distinct components. We performed a single-pulse study based on a one-hour observation at 1.25 GHz on 2021 August 23. We used a threshold of 5σ ep to measure the nulling fraction (NF) as 63% ± 1.5%. The longitude-resolved fluctuation spectra and fast Fourier transform spectra of the binary sequences revealed the quasi-periodicity of nulling with a period of 30 rotation periods. We examined the reliability of the periodicity by comparing it to random noise injection. The NF, Ė , and modulation periodicity P M of PSR J1909+0122 were compared with other periodic nulling pulsars, showing that the source of J1909+0122 has the second largest NF in the population. Long-term timing observations over six months were used to derive the phase-connected ephemeris of this pulsar. The measured P and Ṗ values disfavor dipolar geometry for polar gap models, and the prediction for a space-charge-limited flow model in the case of inverse Compton scattering is only just above the death line. In this work, PSR J1909+0122 has revealed possible correlations between nulling behavior and pulsar properties, which will help to shed light on the pulsar emission mechanism and its temporal evolution in future observations.
作者机构:
[Qu, Jin-Lu; Xu, Ying-Chen; Li, Tian-Ming; Zhang, Shuang-Nan; Liu, Cong-Zhan; Li, Cheng-Kui; Ge, Ming-Yu; Xie, Sheng-Lun; Song, Li-Ming; Fu, Yu-Cong; Tuo, You-Li; Lu, Xue-Feng] Inst High Energy Phys, Key Lab Particle Astrophys, Beijing 100049, Peoples R China.;[Xu, Ying-Chen; Li, Tian-Ming; Zhang, Shuang-Nan; Song, Li-Ming; Lu, Xue-Feng] Univ Chinese Acad Sci, Chinese Acad Sci, Beijing 100049, Peoples R China.;[Cai, Ce] Hebei Normal Univ, Coll Phys, Hebei Key Lab Photophys Res & Applicat, Shijiazhuang 050024, Peoples R China.;[Xie, Sheng-Lun] Cent China Normal Univ, Inst Astrophys, Wuhan 430079, Peoples R China.
关键词:
physical data and processes;radiation: dynamics;radiation mechanisms: general
摘要:
On 2020 April 27, the soft gamma-ray repeater SGR J1935+2154 entered its intense outburst episode again. Insight-HXMT carried out about one month observation of the source. A total number of 75 bursts were detected during this activity episode by Insight-HXMT, and persistent emission data were also accumulated. We report on the spin period search result and the phase distribution of burst start times and burst photon arrival times of the Insight-HXMT high energy detectors and Fermi/Gamma-ray Burst Monitor (GBM). We find that the distribution of burst start times is uniform within its spin phase for both Insight-HXMT and Fermi/GBM observations, whereas the phase distribution of burst photons is related to the type of a burst's energy spectrum. The bursts with the same spectrum have different distribution characteristics in the initial and decay episodes for the activity of magnetar SGR J1935+2154.