학술논문
Pole position of Λ(1405) measured in d(K−,n)πΣ reactions
Document Type
article
Author
S. Aikawa; S. Ajimura; T. Akaishi; H. Asano; G. Beer; C. Berucci; M. Bragadireanu; P. Buehler; L. Busso; M. Cargnelli; S. Choi; C. Curceanu; S. Enomoto; H. Fujioka; Y. Fujiwara; T. Fukuda; C. Guaraldo; T. Hashimoto; R.S. Hayano; T. Hiraiwa; M. Iio; M. Iliescu; K. Inoue; Y. Ishiguro; S. Ishimoto; T. Ishikawa; K. Itahashi; M. Iwai; M. Iwasaki; K. Kanno; K. Kato; Y. Kato; S. Kawasaki; P. Kienle; Y. Komatsu; H. Kou; Y. Ma; J. Marton; Y. Matsuda; Y. Mizoi; O. Morra; R. Murayama; T. Nagae; H. Noumi; H. Ohnishi; S. Okada; Z. Omar; H. Outa; K. Piscicchia; Y. Sada; A. Sakaguchi; F. Sakuma; M. Sato; A. Scordo; M. Sekimoto; H. Shi; K. Shirotori; D. Sirghi; F. Sirghi; K. Suzuki; S. Suzuki; T. Suzuki; K. Tanida; H. Tatsuno; A.O. Tokiyasu; M. Tokuda; D. Tomono; A. Toyoda; K. Tsukada; O. Vazquez-Doce; E. Widmann; T. Yamaga; T. Yamazaki; H. Yim; Q. Zhang; J. Zmeskal
Source
Physics Letters B, Vol 837, Iss , Pp 137637- (2023)
Subject
Language
English
ISSN
0370-2693
Abstract
We measured a set of π±Σ∓, π0Σ0, and π−Σ0 invariant mass spectra below and above the K¯N mass threshold in K−-induced reactions on deuteron. The measured πΣ mass spectral shape is well reproduced via the two-step mechanism, i.e., a neutron knocked out at a forward angle from a deuteron by an incident K−, with the K¯ recoiled backward reacting with the residual nucleon to produce π and Σ. We deduced the S-wave K¯N→πΣ and K¯N→K¯N scattering amplitudes in the isospin 0 channel in the framework of a K¯N and πΣ coupled channel. We find that a resonance pole corresponding to Λ(1405) is located at 1417.7−7.4+6.0 (fitting errors)−1.0+1.1 (systematic errors) + [−26.1−7.9+6.0 (fitting errors)−2.0+1.7 (systematic errors)] i MeV/c2, closer to the K¯N mass threshold than the value determined by the Particle Data Group.