Results are presented from measuring the
cross section and effective neutron timelike form factor. Data are collected in 2020–2021 at the VEPP-2000
collider in the 1891 to 2007 MeV center-of-mass ...range of energies. The general purpose nonmagnetic SND detector is used to detect neutron–antineutron events. The time-of-flight approach is used to select
events. The measured cross section is 0.4–0.6 nbn. The neutron form factor in the investigated range of energies varies from 0.3 to 0.2.
Recent Progress in the VEPP-2000 Collider Rastigeev, S. A.; Aktershev, Yu. S.; Bedarev, E. V. ...
Physics of particles and nuclei letters,
08/2023, Volume:
20, Issue:
4
Journal Article
Peer reviewed
The VEPP-2000 is an electron–positron collider with round beams built and operating at the Budker Institute of Nuclear Physics (BINP). The collider luminosity was increased twofold last year. The ...integrated luminosity accumulated over the last year has exceeded 0.3 fb
–1
, which almost doubled the total data collected since the collider operation began. The short description of the VEPP-2000 complex, current status, and the results are presented in this work.
Status and perspectives of the VEPP-2000 Shatunov, P. Yu; Berkaev, D. E.; Zharinov, Yu. M. ...
Physics of particles and nuclei letters,
12/2016, Volume:
13, Issue:
7
Journal Article
Peer reviewed
The electron-positron collider VEPP-2000 operates at BINP from 2010 year. The application of round colliding beams concept along with the accurate orbit and lattice correction yielded the high peak ...luminosity of 1.2 × 10
31
cm
−2
s
−1
at 500MeV. The peak luminosity limited only by beam-beam effects, while average luminosity–by present lack of positrons in whole energy range of 160–1000 MeV. To perform high luminosity at high energies the top-up injection is needed. At present new electron and positron injection complex at BINP is commissioned and ready to feed VEPP-2000 collider with intensive beams with energy of 450MeV.
VEPP-2000 is the only electron–positron collider with round beams. This factor enables one to increase the beam–beam effect limit. During the 2018–2019 season, the experimental program was focused on ...the energy range of 550–990 MeV per beam. Data accumulation was performed using CMD-3 and SND detectors. The measured luminosity integral proved to have a record value of 68 pb
–1
per detector. After connecting to the BINP injection complex in 2016, the luminosity of VEPP-2000 is limited by the beam–beam effects in the entire energy range.
The cross section of the process e + e − → π + π − has been measured in the center-of-mass energy range from 0.32 to 1.2 GeV with the CMD-3 detector at the electron-positron collider VEPP-2000. The ...measurement is based on an integrated luminosity of about 88 pb − 1 , of which 62 pb − 1 represent a complete dataset collected by CMD-3 at center-of-mass energies below 1 GeV. In the dominant region near the ρ resonance a systematic uncertainty of 0.7% was achieved. The implications of the presented results for the evaluation of the hadronic contribution to the anomalous magnetic moment of the muon are discussed. Published by the American Physical Society 2024
The cross section of the process e + e − → π + π − has been measured in the center of mass energy range from 0.32 to 1.2 GeV with the CMD-3 detector at the electron-positron collider VEPP-2000. The ...measurement is based on a full dataset collected below 1 GeV during three data taking seasons, corresponding to an integrated luminosity of about 62 pb − 1 . In the dominant ρ -resonance region, a systematic uncertainty of 0.7% has been reached. At energies around ϕ -resonance the π + π − production cross section was measured for the first time with high beam energy resolution. The forward-backward charge asymmetry in the π + π − production has also been measured. It shows a strong deviation from the theoretical prediction based on the conventional scalar quantum electrodynamics framework, and it is in good agreement with the generalized vector-meson-dominance and dispersive-based predictions. The impact of the presented results on the evaluation of the hadronic contribution to the anomalous magnetic moment of muon is discussed. Published by the American Physical Society 2024
The VEPP-2000 electron–positron collider has been operating at the Budker Institute of Nuclear Physics (BINP) since 2010. Applying the concept of round colliding beams allowed the record value of the ...beam–beam parameter ξ ∼ 0.12 to be reached. The upgrading of the VEPP-2000 complex, including the connection to the new BINP Injection Complex and modification of the electron–position booster and the BEP–VEPP-2000 transfer channels to work at 1 GeV, resulted in a significant increase in luminosity. Work on statistical data collection using detectors is in progress.
Experiments with the CMD-3 detector at the VEPP-2000 electron–positron collider in the range of center of mass collision energies from 0.32 to 2 GeV have been performed since December 2010. The ...amount of accumulated data corresponds to an integrated luminosity of about 60 pb
-1
. The resultsof a preliminary analysis are presented for the following annihilation channels:
e
+
e
-
→ 3(π
+
π
-
), 2(π
+
π
-
π
0
),
K
+
K
-
π
+
π
-
,
K
+
K
-
,
, and π
+
π
-
. Since processes of electron–positron annihilation that involve the production of multihadron states proceed through several intermediate states, their analysis is necessary for the correct description of the emission-angle and invariant-mass distributions of product particles.
Preliminary results of the first experiments at the new VEPP-2000 e+e− collider are presented. The experiments have been carried out in the center of mass energy range 1–2 GeV with instant luminosity ...1030–1031cm−2s−1 and total integrated luminosity of about 10pb−1. The main e+e− annihilation cross sections, π+π−π0π0,π+π−π0,π0π0γ,andπ+π−η, have been measured. The cross section of nucleon–antinucleon production is also presented.
Since December 2010, the CMD-3 detector has collected data at the electronpositron collider VEPP-2000. The sample of the accumulated data corresponds to about 60 pb−1 of integrated luminosity in the ...c.m. energy from 0.32 up to 2 GeV. Preliminary results of the analysis of various processes e+e− annihilation to hadrons are presented. It is shown the processes with multihadron events have several intermediate states which must be taken into account to correctly describe the angular and invariant mass distributions as well as cross section dependence versus energy.
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