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Within the cluster-core model picture using the preformed cluster model, proton rich, 2-proton emitting nuclei are studied. The experimentally established [Formula: see text]Fe, [Formula: see text]Ni, [Formula: see text]Zn and [Formula: see text]Kr are investigated in terms of simple potential energy surfaces for all possible cluster plus core configurations of the 2-proton emitting nuclei. The calculated potential energy surfaces reveal a strong minimum for 2-proton-cluster plus core configuration. In addition, the calculations are carried out for the theoretically studied 2-proton emitters such as [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text], which also reveal 2-proton cluster plus core configuration as the favorable one possessing strong minimum in the potential energy surface. Furthermore, the calculated potential energies are used to calculate the preformation probability by solving the stationary Schrödinger equation of motion in mass asymmetry coordinate. The formation yield also clearly reveals a larger formation probability for the 2-proton cluster plus core configuration for all the nuclei studied. The Q-value systematic of 1-proton, 2-proton, 4-proton and 4He is also analyzed.

UltimaGold TM AB and OptiphaseTrisafe are two liquid scintillators made by Perkin Elmer and EG & G Company respectively. Both are commercially promoted as scintillation detectors for α and β particles. In this work, the responses to γ-rays and neutrons of UltimaGold TM AB and OptiphaseTriSafe liquid scintillators, without and with reflector, have been measured aiming to use these scintillators as γ-rays and neutron detectors. Responses to γ-rays and neutrons were measured as pulse shape spectra in a multichannel analyzer. Scintillators were exposed to gamma rays produced by 137 Cs, 54 Mn, 22 Na and 60 Co sources. The response to neutrons was obtained with a 241 AmBe neutron source that was measured to 25 and 50 cm from the scintillators. The pulse height spectra due to gamma rays are shifted to larger channels as the photon energy increases and these responses are different from the response due to neutrons. Thus, UltimaGold TM AB and OptiphaseTrisafe can be used to detect γ-rays and neutrons.

A model-independent and [Formula: see text]-dependent four parameter formula has been recently proposed for the studies of one proton and two proton radioactivity. The same form of the formula with different parameter sets worked well for 1p and 2p emission indicating the fact that the similar phenomenological law is able to successfully reproduce both 1p as well as 2p emission half-lives suggesting the identical descriptions of these phenomena. Retaining the same form of the formula, its applicability is studied in this work for calculating the ground state as well as excited state [Formula: see text] emission. For this study, we consider 22 odd–odd nuclei, 31 odd–even nuclei, 52 even–odd nuclei, 88 even–even nuclei with the parent nucleus charge numbers in the range of [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text], respectively. For each of these subsets the emission of [Formula: see text] with different angular momentum values are considered. The general formula with four different parameter sets is proposed and the obtained results are compared with the experimental data. The study reveals that the general form of the proposed empirical formula is suitable for calculating the half-lives of 1p, 2p and [Formula: see text]-emission with different [Formula: see text]-values. With very minimal input like [Formula: see text]-values, and charge number of the daughter nucleus, this formula can be used as a handy tool for a systematic study as well as to plan new experiments.