학술논문
Measurement of the e + e − → π + π − process cross section with the SND detector at the VEPP-2000 collider in the energy region 0.525 < s $$ \sqrt{s} $$ < 0.883 GeV
Document Type
article
Author
SND collaboration; M. N. Achasov; A. A. Baykov; 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. G. Kharlamov; I. A. Koop; A. A. Korol; D. P. Kovrizhin; A. S. Kupich; A. P. Lysenko; K. A. Martin; N. A. Melnikova; N. Yu. Muchnoi; A. E. Obrazovsky; E. V. Pakhtusova; E. A. Perevedentsev; K. V. Pugachev; Y. S. Savchenko; S. I. Serednyakov; Z. K. Silagadze; P. Yu. Shatunov; Yu. M. Shatunov; D. A. Shtol; D. B. Shwartz; I. K. Surin; Yu. V. Usov; I. M. Zemlyansky; V. N. Zhabin
Source
Journal of High Energy Physics, Vol 2021, Iss 1, Pp 1-24 (2021)
Subject
Language
English
ISSN
1029-8479
Abstract
Abstract The cross section of the process e + e − → π + π − has been measured in the Spherical Neutral Detector (SND) experiment at the VEPP-2000 e + e − collider VEPP-2000 in the energy region 525 < s $$ \sqrt{s} $$ < 883 MeV. The measurement is based on data with an integrated luminosity of about 4.6 pb −1. The systematic uncertainty of the cross section determination is 0.8% at s $$ \sqrt{s} $$ > 0.600 GeV. The ρ meson parameters are obtained as m ρ = 775.3 ± 0.5 ± 0.6 MeV, Γ ρ = 145.6 ± 0.6 ± 0.8 MeV, B ρ→e+e− × B ρ→π+π− = (4.89 ± 0.02 ± 0.04) × 10 −5, and the parameters of the e + e − → ω → π + π − process, suppressed by G-parity, as B ω→e+e− × B ω→π+π− = (1.32 ± 0.06 ± 0.02) × 10 −6 and and ϕ ρω = 110.7 ± 1.5 ± 1.0 degrees.