https://doi.org/10.1140/epja/s10050-023-01063-y
Regular Article - Experimental Physics
Diverse mechanisms in proton knockout reactions from the Borromean nucleus 
1
GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291, Darmstadt, Germany
2
Institut für Kernphysik, Technische Universität Darmstadt, 64289, Darmstadt, Germany
3
Instituto Galego de Física de Altas Enerxias, Universidade de Santiago de Compostela, E-15782, Santiago de Compostela, Spain
4
Department of Physics and Astronomy, Texas A &M University-Commerce, 75429, Commerce, TX, USA
5
Instituto de Estructura de la Materia, CSIC, ES–28006, Madrid, Spain
6
Department of Physics, University of Liverpool, L69 3BX, Liverpool, UK
7
NRC Kurchatov Institute, 123182, Moscow, Russia
8
Institutionen för Fysik, Chalmers Tekniska Högskola, 41296, Göteborg, Sweden
9
Institut für Angewandte Physik, Goethe Universität, 60438, Frankfurt am Main, Germany
10
Grupo de Física Nuclear and IPARCOS, Universidad Complutense de Madrid, CEI Moncloa, E-28040, Madrid, Spain
11
Department of Physics and Astronomy, University of Aarhus, 8000, Aarhus, Denmark
12
Institut für Kernchemie Johannes Gutenberg-Universität Mainz, 55122, Mainz, Germany
13
Instytut Fizyki, Uniwersytet Jagelloński, 30-059, Krakóv, Poland
14
Institutionen för fysik och astronomi, Uppsala Universitet, 751 20, Uppsala, Sweden
15
Physik-Department E12, Technische Universität München, 85748, Garching, Germany
16
Nuclear Physics Group, STFC Daresbury Lab, WA4 4AD, Warrington, Cheshire, UK
17
Nuclear Physics Division, Bhabha Atomic Research Centre, Trombay, 400085, Mumbai, India
18
National Centre for Nuclear Research, Radioisotope Centre POLATOM, Andrzeja Sołtana 7, 05-400, Otwock, Poland
19
Department of Physics and Astronomy, College of Science, King Saud University, P.O. Box 2455, 11451, Riyadh, Kingdom of Saudi Arabia
20
National Superconducting Cyclotron Laboratory, MSU, 48824, East Lansing, MI, USA
Received:
13
December
2022
Accepted:
22
June
2023
Published online:
12
July
2023
Nucleon knockout experiments using beryllium or carbon targets reveal a strong dependence of the quenching factors, i.e., the ratio (
) of theoretical to the experimental spectroscopic factors (
), on the proton-neutron asymmetry in the nucleus under study. However, this dependence is greatly reduced when a hydrogen target is used. To understand this phenomenon, exclusive 
and inclusive 
, 
as well as 
(X-denotes undetected reaction products) reactions with 
in the ground and excited states were analysed. The longitudinal momentum distribution of 
and the correlations between the detached protons were studied. In the case of the carbon target, there is a significant deviation from the predictions of the eikonal model. The eikonal approximation was used to extract spectroscopic factor values . The experimental 
value obtained with C target is markedly lower than that for H target. This is interpreted as rescattering due to simultaneous nucleon knockout from both reaction partners, and 
.
W. Ott: Deceased.
© The Author(s) 2023
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