The proton-unbound argon and chlorine isotopes have been studied by measuring trajectories
of their decay-in-flight products by using a tracking technique with micro-strip detectors. The
proton (1p) and two-proton (2p) emission processes have been detected in the measured angular
correlations “heavy-fragment”+p and “heavy-fragment”+p+p, respectively. The ground states of
the previously unknown isotopes 30Cl and 28Cl have been observed for the first time, providing the
1p separation energies Sp of −0.48(2) and −1.60(8) MeV, respectively. The relevant systematics of
1p and 2p separation energies have been studied theoretically in the core+p and core+p+p cluster
models. The first-time observed excited states of 31Ar allow to infer the 2p-separation energy S2p
of 6(34) keV for its ground state. The first-time observed state in 29Ar with S2p = −5.50(18) MeV
can be identified either as a ground or an excited state according to different systematics.This work was supported in part by the Helmholtz International Center for FAIR (HIC for FAIR); the Helmholtz Association (Grant No. IK-RU-002); the Russian Science Foundation (Grant No. 17-12-01367); the Polish National Science Center (Contract No. UMO-2015/17/B/ST2/00581); the Polish Ministry of Science and Higher Education (Grant No. 0079/DIA/2014/43, Grant Diamentowy); the Helmholtz-CAS Joint Research Group (Grant No. HCJRG-108); the Ministry of Education & Science, Spain (Contract No. FPA2016-77689-C2-1-R); the Hessian Ministry for Science and Art (HMWK) through the LOEWE funding scheme Helmholtz International Center for FAIR (HIC for FAIR); the Justus-Liebig-Universitat Giessen (JLU) and the GSI under the JLU-GSI strategic Helmholtz partnership agreement. This work was carried out in the framework of the Super-FRS Experiment collaboration. This article is a part of the Ph.D. thesis of D. Kostyleva
