TY - JOUR
T1 - Study of Δ excitations in medium-mass nuclei with peripheral heavy ion charge-exchange reactions
AU - Rodríguez-Sánchez, J. L.
AU - Benlliure, J.
AU - Vidaña, I.
AU - Lenske, H.
AU - Scheidenberger, C.
AU - Vargas, J.
AU - Alvarez-Pol, H.
AU - Atkinson, J.
AU - Aumann, T.
AU - Ayyad, Y.
AU - Beceiro-Novo, S.
AU - Boretzky, K.
AU - Caamaño, M.
AU - Casarejos, E.
AU - Cortina-Gil, D.
AU - Díaz Fernández, P.
AU - Estrade, A.
AU - Geissel, H.
AU - Haettner, E.
AU - Kelić-Heil, A.
AU - Litvinov, Yu A.
AU - Paradela, C.
AU - Pérez-Loureiro, D.
AU - Pietri, S.
AU - Prochazka, A.
AU - Takechi, M.
AU - Tanaka, Y. K.
AU - Weick, H.
AU - Winfield, J. S.
N1 - Funding Information:
The authors are grateful to the GSI accelerator staff for providing an intense and stable beam of 112 Sn. We thank Dr. L. Álvarez-Ruso for reading the manuscript carefully. This work was partially supported by the Unidad de Excelencia Maria de Maeztu , by Consolider-CPAN-CSD2007-00042 and by the Regional Government of Galicia under the program “Grupos de Referencia Competitiva 2013-011”. I.V. thanks the support from the COST Action CA16214 . J.L.R.S. thanks the support from the Department of Education, Culture and University Organization of the Regional Government of Galicia under the program of postdoctoral fellowships ( ED481B-2017/002 ).
Publisher Copyright:
© 2020 The Author(s)
PY - 2020/8/10
Y1 - 2020/8/10
N2 - Isobaric single charge-exchange reactions, changing nuclear charges by one unit but leaving the mass partitions unaffected, have been for the first time investigated by peripheral collisions of 112Sn ions accelerated up to 1A GeV at the GSI facilities. The high-resolving power of the FRS spectrometer allows us to obtain (p,n)-type isobaric charge-exchange cross sections with an uncertainty of 3.5% and to separate quasi-elastic and inelastic components in the missing-energy spectra of the ejectiles. The inelastic component is associated to the excitation of the Δ(1232) isobar resonance and the emission of pions in s-wave both in the target and projectile nucleus, while the quasi-elastic contribution is associated to the nuclear spin-isospin response of nucleon-hole excitations. An apparent shift of the Δ-resonance peak of ∼63 MeV is observed when comparing the missing-energy spectra obtained from the measurements with proton and carbon targets. A detailed analysis, performed with a theoretical model for the reactions, indicates that this observation can be simply interpreted as a change in the relative magnitude between the contribution of the excitation of the resonance in the target and in the projectile.
AB - Isobaric single charge-exchange reactions, changing nuclear charges by one unit but leaving the mass partitions unaffected, have been for the first time investigated by peripheral collisions of 112Sn ions accelerated up to 1A GeV at the GSI facilities. The high-resolving power of the FRS spectrometer allows us to obtain (p,n)-type isobaric charge-exchange cross sections with an uncertainty of 3.5% and to separate quasi-elastic and inelastic components in the missing-energy spectra of the ejectiles. The inelastic component is associated to the excitation of the Δ(1232) isobar resonance and the emission of pions in s-wave both in the target and projectile nucleus, while the quasi-elastic contribution is associated to the nuclear spin-isospin response of nucleon-hole excitations. An apparent shift of the Δ-resonance peak of ∼63 MeV is observed when comparing the missing-energy spectra obtained from the measurements with proton and carbon targets. A detailed analysis, performed with a theoretical model for the reactions, indicates that this observation can be simply interpreted as a change in the relative magnitude between the contribution of the excitation of the resonance in the target and in the projectile.
KW - Baryon resonances
KW - Fragment separator FRS
KW - Inverse kinematics
UR - http://www.scopus.com/inward/record.url?scp=85087023664&partnerID=8YFLogxK
U2 - 10.1016/j.physletb.2020.135565
DO - 10.1016/j.physletb.2020.135565
M3 - Article
AN - SCOPUS:85087023664
VL - 807
JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
SN - 0370-2693
M1 - 135565
ER -