Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userSpherical Neutral Detector for VEPP-2M collider
88
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
The Spherical Neutral Detector (SND) operates at VEPP-2M collider in Novosibirsk studying e^+e^- annihilation in the energy range up to 1.4 GeV. Detector consists of a fine granulated spherical scintillation calorimeter with 1632 NaI(Tl) crystals, two cylindrical drift chambers with 10 layers of sense wires, and a muon system made of streamer tubes and plastic scintillation counters. The detector design, performance, data acquisition and processing are described.
rate research
Read More
Short overview of experiments with SND detector at VEPP-2M e^+e^- collider in the energy range 2E = 400 - 1400 MeV and preliminary results of data analysis are presented.
The current status of experiments with SND detector at VEPP-2M $e^+e^-$ collider in the energy range $2E_0=0.4-1.4$ GeV is given. The new results of analysis of $phi$ decay into $pi^0pi^0gamma$, $etapi^0gamma$ are based on the full SND statistics corresponding 20 million of $phi$ decay. New measurement of $omegatopi^0pi^0gamma$ decay and a first observation of $rhotopi^0pi^0gamma$ are presented. The accuracy of many other rare decays of light vector mesons was improved. In the energy range $2E_0=1.0div1.4$ GeV the cross sections of the processes $e^+e^-toomegapi^0$ and $e^+e^-topi^+pi^-pi^0$ were measured. The results of the fitting of data are discussed.
The $phi$(1020) meson leptonic width has been determined from the combined analysis of 4 major decay modes of the resonance ($phito K^+ K^-,K^0_LK^0_S,pi^+pi^-pi^0,etagamma$) studied with the CMD-2 detector at the VEPP-2M $e^+e^-$ collider. The following value has been obtained: $Gamma(phito e^+e^-) = 1.235pm 0.006pm 0.022$ keV. The $phi(1020)$ meson parameters in four main decay channels have been also recalculated: $B(phito K^+K^-) = 0.493pm 0.003pm 0.007$, $B(phito K_LK_S) = 0.336pm 0.002pm 0.006$, $B(phitopi^+pi^-pi^0) = 0.155pm 0.002pm 0.005$, $B(phitoetagamma) = 0.0138pm 0.0002pm 0.0002$.
The paper describes experiments with the SND detector at VEPP-2M collider, carried out during the period from October 1995 until June 1997. The total integrated luminosity of 6.4 pb^{-1} was collected in the energy range 2E=0.4-1.4 GeV (MHAD97 experiment), corresponding to 4*10^5 mu^+ mu^- pairs produced. Preliminary results of the 1996 phi-meson experiment (FI96) are presented. The total number of phi-mesons produced is 4*10^6. New data on rare decays of phi and eta (550) mesons, in particular B(phi -> eta gamma) = (1.30+-0.06+-0.07)%, B(phi -> pi^0 pi^0 gamma) = (1.1+-0.2)*10^{-4}, (M_{pi^0 pi^0} > 800 MeV), B(phi -> f^0 gamma) = (4.7+-1.0)*10^{-4}, B(phi -> eta pi^0 gamma) = (1.3+-0.5)*10^{-4}, B(phi -> eta gamma) < 1.7*10^{-4}, B(phi -> 2 pi^0 ) < 6*10^{-4} were obtained.
The $e^+e^-toetagammato 7gamma$ process was studied in the energy range $2E=600div 1060$ MeV with an SND detector on a VEPP-2M $e^+e^-$ collider. The decay branching ratios $B(phitoetagamma)=(1.343pm 0.012pm 0.055)cdot 10^{-2}$, $B(omegatoetagamma)=(4.60pm 0.72pm 0.19)cdot 10^{-4}$, and $B(rhotoetagamma)=(2.69pm 0.32pm 0.16)cdot 10^{-4}$ were measured.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
