학술논문
Isovector soft dipole mode in 6Be
Document Type
Working Paper
Author
Fomichev, A. S.; Chudoba, V.; Egorova, I. A.; Ershov, S. N.; Golovkov, M. S.; Gorshkov, A. V.; Gorshkov, V. A.; Grigorenko, L. V.; Kamiński, G.; Krupko, S. A.; Mukha, I. G.; Parfenova, Yu. L.; Sidorchuk, S. I.; Slepnev, R. S.; Standyło, L.; Stepantsov, S. V.; Ter-Akopian, G. M.; Wolski, R.; Zhukov, M. V.
Source
Subject
Language
Abstract
By using the 1H(6Li,6Be)n charge-exchange reaction, continuum states in 6Be were populated up to E_t=16 MeV, E_t being the 6Be energy above its three-body decay threshold. In kinematically complete measurements performed by detecting alpha+p+p coincidences, an E_t spectrum of high statistics was obtained, containing approximately ~5x10^6 events. The spectrum provides detailed correlation information about the well-known 0^+ ground state of 6Be at E_t=1.37 MeV and its 2^+ state at E_t=3.05 MeV. Moreover, a broad structure extending from 4 to 16 MeV was observed. It contains negative parity states populated by Delta L=1 angular momentum transfer without other significant contributions. This structure can be interpreted as a novel phenomenon, i.e. the isovector soft dipole mode associated with the 6Li ground state. The population of this mode in the charge-exchange reaction is a dominant phenomenon for this reaction, being responsible for about 60% of the cross section obtained in the measured energy range.
Comment: 8 pages, 7 figures
Comment: 8 pages, 7 figures