Search for the $η^{\prime}\to e^+e^-$ decay with the SND detector
M. N. Achasov, V. M. Aulchenko, A. Yu. Barnyakov, K. I. Beloborodov, A. V. Berdyugin, D. E. Berkaev, A. G. Bogdanchikov, A. A. Botov, T. V. Dimova, V. P. Druzhi… 展开作者
M. N. Achasov, V. M. Aulchenko, A. Yu. Barnyakov, K. I. Beloborodov, A. V. Berdyugin, D. E. Berkaev, A. G. Bogdanchikov, A. A. Botov, T. V. Dimova, V. P. Druzhinin, V. B. Golubev, L. V. Kardapoltsev, A. S. Kasaev, A. G. Kharlamov, A. N. Kirpotin, I. A. Koop, A. A. Korol, S. V. Koshuba, D. P. Kovrizhin, A. S. Kupich, K. A. Martin, N. Yu. Muchnoi, A. E. Obrazovsky, A. V. Otboev, E. V. Pakhtusova, A. I. Senchenko, S. I. Serednyakov, P. Yu. Shatunov, Yu. M. Shatunov, D. A. Shtol, D. B. Shwartz, Z. K. Silagadze, I. K. Surin, Yu. A. Tikhonov, Yu. V. Usov, A. V. Vasiljev, I. M. Zemlyansky
A search for the process $e^+e^- \to η^\prime$ has been performed with the SND detector at the VEPP-2000 $e^+e^-$ collider. The data were accumulated at the center-of-mass energy of $957.78\pm 0.06$ MeV with an integrated luminosity of about 2.9 pb$^{-1}$. For reconstruction of the $η^\prime$ meson five decay chains have been used: $η^{\prime}\toηπ^+π^-$ followed by the $η$ decays to $γγ$ and $3π^0 $, and $η^{\prime} \to ηπ^0π^0$ followed by the $η$ decays to $π^+π^-π^0$, $γγ$, and $3π^0$. As a result, the upper limit has been set on the $η^\prime$ electronic width: $Γ_{η^{\prime}\to e^+e^-} < 0.0020$ eV at the 90\% confidence level.
Measurement of the e+e- -> K+K- cross section in the energy range s**(1/2) = 1.04 - 1.38 GeV with the SND detector in the experiment at the VEPP-2M e+e- collider
在VEPP-2 M $e^+e^-$对撞机上进行的SND实验中，在能量范围$\sqrt{s}$ = 1.04- 1.38 GeV内测量了过程$e^+e^- \to K^+K^-$的截面。测量的截面用矢量介子占优势的模型来描述，该模型考虑了轻矢量介子$ρ$、$ω$、$ϕ$及其最低激发态的贡献.测量的平均统计准确度为4.4%，系统不确定度为5.2%。
本文介绍了在VEPP-2 M $e^+e^-$对撞机上进行的$2E_0=0.4-1.4$ GeV能区SND探测器实验的现状。分析$ϕ$衰变为$π^0π^0γ$、$ηπ^0γ$的新结果是基于对应于2000万个$ϕ$衰变的完整SND统计。本文介绍了对$ω\toπ^0π^0γ$衰变的新测量和对$ρ\toπ^0π^0γ$的首次观测。光矢量介子的许多其他罕见衰变的准确性得到了提高。在能量范围$2E_0=1.0\div1.4$ GeV的过程$e^+e^-\toωπ^0$和$e^+e^-\toπ^+π^-π^0$的截面进行了测量。对数据拟合的结果进行了讨论。
New results on e+e- -> hadrons exclusive cross sections from experiments with SND detector at VEPP-2M e+e- collider in the energy range sqrt(s)=0.4-1.4 GeV
给出了e+e-> pi+pi-，K+K-，K_SK_L，pi_0/γ，eta_0/γ过程截面测量的新结果。这些结果是基于1995-2000年间VEPP-2 M e+e对撞机SND探测器在sqrt（s）=0.4-1.4 GeV能量范围内积累的30 pb^-1数据。与现有实验数据的比较表明，测量精度接近或优于世界平均水平。对于e+e-> pi+pi-过程，精度约为0.01。这对计算强子对μ子反常磁矩的贡献是重要的。
European Organization for Nuclear Research (CERN)（欧洲核子研究中心）；Pakistan Institute of Nuclear Science and Technology（巴基斯坦核科学与技术研究所）；Institute of Physics, EPFL（洛桑联邦理工学院物理研究所）；Chulalongkorn University（朱拉隆功大学）；Millennium Institute for Subatomic physics at high energy frontier-SAPHIR（高能前沿亚原子物理千禧年研究所-SAPHIR）；Hamburg University（汉堡大学）；Laboratory of Instrumentation and Experimental Particle Physics (LIP)（仪器与实验粒子物理实验室）；Sofia University（索非亚大学）；University of Leiden（莱顿大学）；Taras Shevchenko National University of Kyiv（基辅塔拉斯舍甫琴科国立大学）；University College London（伦敦大学学院）；Sungkyunkwan University（成均馆大学）；Laboratori Nazionali del Gran Sasso（格兰萨索国家实验室）；Middle East Technical University (METU)（中东理工大学）；Atilim University（阿提利姆大学）；Imperial College London（帝国理工学院）；Constructor University（Constructor 大学）；Gyeongsang National University（庆尚国立大学）；Gwangju National University of Education（光州国立教育大学）；Nagoya University（名古屋大学）；Korea University（高丽大学）；Pegaso University（佩加索大学）；Chiang Mai University（清迈大学）；Toho University（东海大学）；Niels Bohr Institute（尼尔斯·玻尔研究所）
Measurement of the $e^+e^- \to ηπ^+π^-$ cross section in the center-of-mass energy range 1.22--2.00 GeV with the SND detector at the VEPP-2000 collider
Measurement of the $e^+e^- \toπ^+π^- $ process cross section with the SND detector at the VEPP-2000 collider in the energy region $0.525<\sqrt{s}<0.883$ GeV
Institute for Nuclear Research of the Russian Academy of Sciences（俄罗斯科学院核物理研究所）；I.E. Tamm Department of Theoretical Physics, Lebedev Physical Institute（列别杰夫物理研究所伊.E.塔姆理论物理系）
Study of e+e- --> omega pi0 --> pi0 pi0 gamma in the energy range 1.05--2.00 GeV with SND
在1.05- 2.00 GeV能量范围内，测量了e+e-> omega pi 0--> pi 0 pi 0 γ过程的截面。实验是在VEPP-2000电子对撞机上用SND探测器进行的.测得的1.4 GeV以上的e+e-> omega pi 0截面是迄今为止最精确的。在1.4 GeV以下，我们的数据与以前的SND和CMD-2测量结果吻合得很好。e+e-> omega pi 0截面的数据很好地描述了VMD模型与两个激发的rho-like状态。从测量的截面中，我们提取了γ ^* --> ω π 0跃迁形状因子。发现VDM模型不能同时描述我们的数据和从ω-> pi 0 μ + μ衰变得到的数据。我们还测试了CVC假设，将我们在e+e-> omega pi 0截面上的结果与在tau-> omega pi- nu_{tau}衰变上的数据进行比较。
$ZZ \to \ell^{+}\ell^{-}\ell^{\prime +}\ell^{\prime -}$ cross-section measurements and search for anomalous triple gauge couplings in 13 TeV $pp$ collisions with the ATLAS detector
