Evidence of large nuclear deformation ofS32*formed in the

A. Dey

¹

,

Subhashish Bhattacharya

²

,

C. Bhattacharya

³

et al.

Abstract

Deformations of hot composite 32 S * formed in the reaction 20 Ne(∼7-10 MeV/nucleon) + 12 C have been estimated from the respective inclusive α-particle evaporation spectra. The estimated deformations for 32 S * have been found to be much larger than the "normal" deformations of hot, rotating composites at similar excitations. This further confirms the formation of a highly deformed long-lived configuration of 20 Ne + 12 C at high excitations (∼70-100 MeV)-which was recently indicated from analysis of complex fragment emission data for the same system. Exclusive α-particle evaporation spectra from the decay of hot composite 32 S * also show similar behavior.

Signature of clustering in quantum many-body systems probed by the giant dipole resonance

“…It is now well known that these cluster structures are associated with strongly deformed shapes of nuclei. The deformations, estimated from the respective α-particle evaporation spectra in the reaction 20 Ne + 12 C, have been found to be much larger compared to normal deformation attained by hot rotating composites at similar excitation energies [13]. However, there has been no direct measurement of this deformation at high excitation energies and angular momenta.…”

Deformation in28Si*produced via the16O+Kundu1, Bhattacharya2, Bhattacharya3 et al. 2013Phys. Rev. CSelf Cite

“…Following [11], the effective radius parameter, r eff , is defined as r eff = r 0 (1 + δ 1 J 2 + δ 2 J 4 ), and the average effective radius parameter is calculated using the expression, r eff = j cr 0 r eff (2j + 1)/ j cr 0 (2j + 1). Then the deviation of r eff from r 0 is the measure of deformation, and the deviation of the same from the corresponding RLDM value may be considered as an enhancement.…”

“…The parameters are given in Table I. The level density used in regions II and III for a given angular momentum J and excitation energy E is given by well-known Fermi-gas expression [11] with equidistant single-particle levels and a constant level density parameter a:…”

“…Detailed studies of the deformation of 40 Ca * [9,10] and 32 S * [11] were done recently with the help of light charged particle (LCP) spectroscopy to extract "anomalous" deformation in these cases confirming the presence of DIO mechanism. For these systems, orbiting ( 40 Ca * [6,7], 32 S * [1-3]) had already been conjectured from the fragment emission studies.…”

“…An orbiting dinuclear complex is assumed to be more deformed than a fully shape equilibrated CN; this motivated us to look for such enhanced deformation in a 16 O + 12 C dinuclear system at same excitation energies using the LCP spectroscopy technique. In this technique, LCPs, evaporated from the excited composites, are used to study the properties of hot rotating nuclear systems as a function of excitation energy, angular momentum, and deformation [11,[13][14][15][16][17][18][19][20][21][22][23][24][25] using statistical model codes, e.g., CASCADE [26], GANES [27], CACARIZO [28].…”