Neutron-rich nuclei around N = 16 shell closure

Laser Spectroscopy of Neutron-Rich Hg207,208 Isotopes: Illuminating the Kink and Odd-Even Staggering in Charge Radii across the N=126 Shell Closure

Physical Review Letters ◽

10.1103/physrevlett.126.032502 ◽

2021 ◽

Vol 126 (3) ◽

Author(s):

T. Day Goodacre ◽

A. V. Afanasjev ◽

A. E. Barzakh ◽

B. A. Marsh ◽

S. Sels ◽

...

Keyword(s):

Laser Spectroscopy ◽

Shell Closure ◽

Charge Radii

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ALPHA-DECAY STUDIES ON 130-153Eu NUCLEI

International Journal of Modern Physics E ◽

10.1142/s021830131350081x ◽

2013 ◽

Vol 22 (11) ◽

pp. 1350081 ◽

Cited By ~ 14

Author(s):

K. P. SANTHOSH ◽

B. PRIYANKA

Keyword(s):

Experimental Data ◽

Potential Model ◽

Alpha Decay ◽

Shell Closure ◽

Proximity Potential ◽

Deformed Nuclei ◽

Neutron Shell ◽

Good Agreement ◽

Neutron Shell Closure

The alpha-decay half-lives of the 24 isotopes of Eu (Z = 63) nuclei in the region 130≤A≤153, have been studied systematically within the Coulomb and proximity potential model (CPPM). We have modified the assault frequency and re-determined the half-lives and they show a better agreement with the experimental value. We have also done calculations on the half-lives within the recently proposed Coulomb and proximity potential model for deformed nuclei (CPPMDN). The computed half-lives are compared with the experimental data and they are in good agreement. Using our model, we could also demonstrate the influence of the neutron shell closure at N = 82, in both parent and daughter nuclei, on the alpha-decay half-lives.

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Shell closure effects studied via cluster decay in heavy nuclei

Journal of Physics G Nuclear and Particle Physics ◽

10.1088/0954-3899/36/1/015110 ◽

2008 ◽

Vol 36 (1) ◽

pp. 015110 ◽

Cited By ~ 11

Author(s):

Sushil Kumar ◽

Ramna Rani ◽

Rajesh Kumar

Keyword(s):

Cluster Decay ◽

Shell Closure ◽

Heavy Nuclei

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Laser and decay spectroscopy of the short-lived isotope Fr214 in the vicinity of the N=126 shell closure

Physical Review C ◽

10.1103/physrevc.94.054305 ◽

2016 ◽

Vol 94 (5) ◽

Cited By ~ 8

Author(s):

G. J. Farooq-Smith ◽

T. E. Cocolios ◽

J. Billowes ◽

M. L. Bissell ◽

I. Budinčević ◽

...

Keyword(s):

Shell Closure ◽

Decay Spectroscopy

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Particle entropy and depairing in hot nuclei

International Journal of Modern Physics E ◽

10.1142/s0218301316500932 ◽

2016 ◽

Vol 25 (11) ◽

pp. 1650093 ◽

Cited By ~ 1

Author(s):

J. Dhivya Saranya ◽

N. Boomadevi ◽

T. R. Rajasekaran

Keyword(s):

Single Particle ◽

Mass Region ◽

Shell Closure ◽

Critical Temperatures ◽

Level Densities ◽

Hot Nuclei ◽

Pairing Correlations ◽

Experimental Values ◽

Low Entropy ◽

Interesting Analogy

The nuclear level densities and single particle entropies are predicted for nuclei in the mass region [Formula: see text] within a framework of statistical theory of hot nuclei method. In this method, particle-number and energy conservation as well as nuclear pairing correlations are included in the partition function of grand canonical ensemble. The suppression of pairing correlations is distinctly noticed in temperature dependence of entropies between the critical temperatures [Formula: see text] MeV and [Formula: see text] MeV for [Formula: see text], [Formula: see text] and [Formula: see text] isotopes of the elements. These structural thermodynamic entropies are interpreted as a remarkable signature of the superfluid to normal phase transition connected to the vanishing of pairing gap. The calculated level densities are compared with recent experimental values. In addition, the single particle entropy of intermediate-mass nuclei is depicted as half of the entropy of mid-shell nuclei in the rare-earth region. As a consequence, the [Formula: see text] shell closure of [Formula: see text]V carries low entropy at low excitation energy presents an interesting analogy to the [Formula: see text] shell closure of [Formula: see text]Ni. Merely, in the case of odd–even [Formula: see text] has higher entropy than the even–even [Formula: see text] nucleus.

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Implications of occupancy of 2s1/2 state in sd-shell within RMF+BCS approach

International Journal of Modern Physics E ◽

10.1142/s0218301317500720 ◽

2017 ◽

Vol 26 (11) ◽

pp. 1750072 ◽

Cited By ~ 11

Author(s):

G. Saxena ◽

M. Kumawat ◽

M. Kaushik ◽

U. K. Singh ◽

S. K. Jain ◽

...

Keyword(s):

Mean Field ◽

The Other ◽

Magic Numbers ◽

Neutron Density ◽

Shell Closure ◽

Weakly Bound ◽

Density Profiles ◽

Relativistic Mean Field ◽

Structure Formula ◽

Bubble Structure

We employ the relativistic mean-field plus BCS (RMF+BCS) approach to study the behavior of [Formula: see text]-shell by investigating in detail the single particle energies, and proton and neutron density profiles along with the deformations and radii of even–even nuclei. Emergence of new shell closure, weakly bound structure and most recent phenomenon of bubble structure are reported in the [Formula: see text]-shell. [Formula: see text]C, [Formula: see text]O and [Formula: see text]S are found to have a weakly bound structure due to particle occupancy in 2[Formula: see text] state. On the other hand [Formula: see text]O, [Formula: see text]Ca and [Formula: see text]Si are found with depleted central density due to the unoccupied 2[Formula: see text] state and hence they are the potential candidates of bubble structure. [Formula: see text]C and [Formula: see text]O emerge as doubly magic with [Formula: see text] in accord with the recent experiments and [Formula: see text]S emerges as a new proton magic nucleus with [Formula: see text]. [Formula: see text] and [Formula: see text] are predicted as magic numbers in doubly magic [Formula: see text]O, [Formula: see text]Ca and [Formula: see text]Si, respectively. These results are found in agreement with the recent experiments and have consistent with the other parameters of RMF and other theories.

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Rapid shell closure in the brachiopods Terebratulina retusa and Terebrataua transversa

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400059361 ◽

1992 ◽

Vol 72 (3) ◽

pp. 579-598 ◽

Cited By ~ 3

Author(s):

Spafford C. Ackerly

Keyword(s):

Detailed Analysis ◽

Hydrodynamic Model ◽

Puget Sound ◽

Muscle Length ◽

Adductor Muscle ◽

Muscle Physiology ◽

Shell Closure ◽

Functional Architecture ◽

Adductor Muscles ◽

Kinematic Properties

Rapid shell closure in articulate brachiopods, occurring by a twitch contraction of the the ‘quick’ adductor muscles, is a response to disturbance or to physiological requirements of the organism. The relative simplicity of the closing system permits a detailed analysis of the functional architecture of the mechanism and the underlying principles of skeleto-muscular organization, in terms of (1) basic kinematic properties of the system (speeds and times of closure), (2) hydrodynamic reactions resisting closure, and (3) considerations of muscle physiology and mechanics.Analyses of shell closure in the brachiopods Terebratulina retusa from the Firth of Lorn, Scotland, and Terebratalia transversa from Puget Sound, USA, reveal (1) shell-closing times of the order of 50 to 70 ms, (2) closing velocities of the order of 3·5 radians s-1, from initial gapes of about 0·05 to 0·2 rad, and (3) muscle moment forces and hydrodynamic reactions with magnitudes of the order of 5 × 10-4 N m (5 g cm). Muscle tensions developed in the ‘quick’ adductor muscle are of the order of 105 N m2, and contraction velocities are of the order of one muscle length per second. Hydrodynamic reactions are a fundamental constraint on the closing mechanism, as determined by the concordance of actual closing events with predictions of a hydrodynamic model.

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The cardiac responses to shell opening and closure in the bivalve Arctica islandica (L.)

Journal of Experimental Biology ◽

10.1242/jeb.64.3.751 ◽

1976 ◽

Vol 64 (3) ◽

pp. 751-759

Author(s):

A. C. Taylor

Keyword(s):

Heart Rate ◽

Oxygen Tension ◽

Mantle Cavity ◽

Initial Increase ◽

Shell Closure ◽

Low Oxygen ◽

Arctica Islandica ◽

Cardiac Responses ◽

Lower Oxygen ◽

Pumping Activity

Shell closure in Arctica islandica is followed by an exponential decrease in the oxygen tension of the mantle cavity water and is accompanied by an initial increase in heart rate which is followed at lower oxygen tensions by a bradycardia. Prior to shell opening there is a slight increase in heart rate before any movement of the shell valves can be detected. However, once the shell opens and pumping activity recommences there is a rapid increase in heart rate, often to levels above normal. Perfusion of the mantle cavity with water of high and low oxygen tension resulted in the cardiac responses normally associated with shell opening and closure. Recordings of the PO2 of the blood in the ventricle, made simultaneously with cardiac recordings, showed that the changes in heart rate were recorded only after the PO2 of the blood had changed. These experiments suggest that changes in the PO2 of the mantle cavity water may be primarily responsible for the cardiac responses to shell closure in Arctica.

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