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Related papers: The Nuclear Pairing Gap -- How Low Can It Go?

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The interplay of pairing is explored for the spectral statistics of nuclear systems with emphasis on the nearest neighbor spacing distributions by employing the kernel density and maximum likelihood estimation techniques. Different…

Nuclear Theory · Physics 2013-06-25 H. Sabri , B. Rashidian Maleki , J. Fouladi , N. Fouladi , M. A. Jafarizadeh

Excited states in $^{20}$O were populated in the reaction $^{10}$Be($^{14}$C,$\alpha$) at Florida State University. Charged particles were detected with a particle telescope consisting of 4 annularly segmented Si surface barrier detectors…

We present results from recent time-of-flight nuclear mass measurements at the National Superconducting Cyclotron Laboratory at Michigan State University. We report the first mass measurements of 48Ar and 49Ar and find atomic mass excesses…

Mass distribution of black holes in low-mass X-ray binaries previously suggested the existence of a $ \sim 2-5M_{\odot} $ mass gap between the most massive neutron stars and the least massive black holes, while some recent evidence appears…

High Energy Astrophysical Phenomena · Physics 2022-11-30 Yong Shao

We report ab initio calculations of the S wave pairing gap in neutron matter calculated using realistic nuclear Hamiltonians that include two- and three-body interactions. We use a trial state, properly optimized to capture the essential…

Nuclear Theory · Physics 2022-02-08 S. Gandolfi , G. Palkanoglou , J. Carlson , A. Gezerlis , K. E. Schmidt

The pairing gap plays a fundamental role in the nuclear many-body problem and many large scale and accurate mass formula fits suggest the smooth nuclear mass dependence $\Delta \sim 6(1)~ A^{-1/3}~{\rm MeV}$ in the liquid drop model which…

Nuclear Theory · Physics 2017-06-30 E. Ruiz Arriola , S. Szpigel , V. S. Timoteo

The $\gamma$-circular polarizations ($P_{\gamma}$) and asymmetries ($A_{\gamma}$) of the parity forbidden M1 + E2 $\gamma$-decays: $^{36}Cl^{\ast} (J^{\pi} = 2^{-}; T = 1; E_{x} = 1.95 $ MeV) $\rightarrow$ $^{36}Cl (J^{\pi} = 2^{+}; T = 1;…

Nuclear Theory · Physics 2008-11-26 Mihai Horoi

The even-Z odd-N neutron-halo nuclei, which are the possible lightest neutron-halo nuclei heavier than $^{37}$Mg, are explored by studying the shell-structure unique in weakly-bound neutrons for spherical or deformed shape. It is pointed…

Nuclear Theory · Physics 2017-05-24 Ikuko Hamamoto

We calculate the $^1S_0$ pairing gap in nuclear matter by adopting the "in-medium Bonn potential" proposed by Rapp et al. [e-print nucl-th/9706006], which takes into account the in-medium meson mass decrease, as the particle-particle…

Nuclear Theory · Physics 2009-10-31 Masayuki Matsuzaki , Tomonori Tanigawa

We analyze the low energy NN interaction by confronting statistical vs systematic uncertainties. This is carried out with the help of model potentials fitted to the Granada-2013 database where a statistically meaningful partial wave…

Nuclear Theory · Physics 2016-06-15 R. Navarro Perez , J. E. Amaro , E. Ruiz Arriola

We sketch an approximate method to quantify the number of correlated pairs in any nucleus $A$. It is based on counting independent-particle model (IPM) nucleon-nucleon pairs in a relative $S$-state with no radial excitation. We show that…

Nuclear Theory · Physics 2014-03-21 Wim Cosyn , Maarten Vanhalst , Jan Ryckebusch

Large scale Hartree-Fock-Bogoliubov (HFB) calculations with the finite-range Gogny force D1S have been performed in order to extract the corresponding theoretical average mass dependence of the nuclear gap values. Good agreement with…

Nuclear Theory · Physics 2016-09-08 S. Hilaire , J. -F. Berger , M. Girod , W. Satula , P. Schuck

Supernova theory has struggled to explain the lightest known neutron star candidate with an accurate mass determination, the $1.174\mathrm{M}_\odot$ companion in the eccentric compact binary system J0453+1559. To improve the theoretical…

High Energy Astrophysical Phenomena · Physics 2025-01-16 Bernhard Müller , Alexander Heger , Jade Powell

A realistic nuclear mean-field hamiltonian with pairing has been diagonalized using Fock space representation that allows for nearly exact treatment of the problem. Calculations were performed for all the even-even nuclei with Z in (20,…

Nuclear Theory · Physics 2007-05-23 J. Dudek , K. Mazurek , B. Nerlo-Pomorska

The linear response approach to nuclear transport has been extended to pair correlations. The latter are treated within a mean field approximation to a pairing interaction with constant matrix elements $G$. The constraint of particle number…

Nuclear Theory · Physics 2009-10-31 F. A. Ivanyuk , H. Hofmann

The spectral statistics of low--lying states of several $fp$ shell nuclei are studied with realistic shell--model calculations. For Ca isotopes, we find significant deviations from the predictions of the random--matrix theory which suggest…

Nuclear Theory · Physics 2009-10-28 E. Caurier , J. M. G. Gomez , V. R. Manfredi , L. Salasnich

Valence-shell nucleon knock-out experiments, such as 12C(e,e'p)11B, measure less strength then is predicted by independent particle shell model calculations. The theoretical solution to this problem is to include the correlations between…

Nuclear Experiment · Physics 2015-05-20 Douglas W. Higinbotham

Isochronous mass spectrometry has been applied in the storage ring CSRe to measure the masses of the neutron-rich $^{\operatorname{52-54}}$Sc and $^{54,56}$Ti nuclei. The new mass excess values $ME$($^{52}$Sc) $=$ $-40525(65)$ keV,…

Pairing interactions with various density dependencies (surface/volume mixing) are constrained with the two-neutron separation energy in the Tin isotopic chain. The response associated with pairing vibrations in very neutron-rich nuclei is…

Nuclear Theory · Physics 2009-11-06 Elias Khan , Marcella Grasso , Jerome Margueron

We have reported shell-model results for $^{47-58}$Ca isotopes in the $fp$, $fpg_{9/2}$ and $fpg_{9/2}d_{5/2}$ model spaces using realistic $NN$ interaction. We have also performed a systematic shell-model study using interactions derived…

Nuclear Theory · Physics 2020-05-06 Bharti Bhoy , Praveen C. Srivastava , Kazunari Kaneko