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Related papers: Supernova electron capture rates on odd-odd nuclei

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It has been suggested that hydrogen ingestion into the helium shell of massive stars could lead to high $^{13}$C and $^{15}$N excesses when the shock of a core-collapse supernova passes through its helium shell. This prediction questions…

Recently many authors have performed shell-model calculations of nuclear matrix elements determining the rates of the ordinary muon capture in light nuclei. These calculations have employed well-tested effective interactions in large scale…

Nuclear Theory · Physics 2009-10-31 T. Siiskonen , J. Suhonen , M. Hjorth-Jensen

We report measurements of $\gamma$--ray spectra from muon capture on $^{35}$Cl. For the allowed Gamow--Teller transitions to the $^{35}$S$(2939, 3/2^+)$ state and the $^{35}$S$(3421, 5/2^+)$ state we obtained their capture rates, hyperfine…

Neutron-capture reactions on $^{18}$F in the helium-burning shell play an important role in the production of $^{15}$N during core-collapse supernovae. The competition between the $^{18}$F($n,p/\alpha$)$^{18}$O/$^{15}$N reactions controls…

The re-analysis of the published experimental data on the primary gamma-transition intensities following neutron capture in different groups of neutron resonances in $^{156,158}$Gd has been performed. There are determined the most probable…

Nuclear Experiment · Physics 2009-06-17 A. M. Sukhovoj , V. A. Khitrov

{ The ground-state to ground-state electron-capture $Q$ value of $^{159}$Dy ($3/2^-$) has been measured directly utilizing the double Penning trap mass spectrometer JYFLTRAP. A value of 364.73(19)~keV was obtained from a measurement of the…

A new general expression is derived for nuclear electron capture rates within dense plasmas. Its qualitative nature leads us to question some widely accepted assumptions about how to calculate the effects of the plasma on the rates. A…

Solar and Stellar Astrophysics · Physics 2011-07-04 R. F. Sawyer

The acquisition of precise and reliable nuclear data is a prerequisite to success for stellar evolution and nucleosynthesis studies. Core-collapse simulators find it challenging to generate an explosion from the collapse of the core of…

Nuclear Theory · Physics 2015-05-30 Jameel-Un Nabi , Abdel Nasser Tawfik

Nuclear electron capture rate from continuum in an astrophysical plasma environment (like solar core) is calculated using a modified Debye-Huckel screening potential and the related non-Gaussian q-distribution of electron momenta. For q=1…

Nuclear Theory · Physics 2009-03-04 P. Quarati , A. M. Scarfone

The odd-odd fp-shell nucleus 52Sc was investigated using in-beam gamma-ray spectroscopy following secondary fragmentation of a 55V and 57Cr cocktail beam. Aside from the known gamma-ray transition at 674(5)keV, a new decay at E_gamma=212(3)…

In the first stage of this work, we perform detailed calculations for the cross sections of the electron capture on nuclei under laboratory conditions. Towards this aim we exploit the advantages of a refined version of the proton-neutron…

Nuclear Theory · Physics 2015-02-26 P. G. Giannaka , T. S. Kosmas

We use a high resolution $^{32}{\rm S}(d,t)$ measurement to investigate the claimed existence of a 6401(3) keV state in $^{31}$S that may affect the $^{30}{\rm P}(p,\gamma)$ nuclear reaction rate in oxygen-neon (ONe) novae. Our data are…

Gamow-Teller strength functions in full $(pf)^{8}$ spaces are calculated with sufficient accuracy to ensure that all the states in the resonance region have been populated. Many of the resulting peaks are weak enough to become unobservable.…

Nuclear Theory · Physics 2009-01-23 E. Caurier , A. Poves , A. P. Zuker

In a superhigh magnetic field, direct Urca reactions can proceed for an arbitrary proton concentration. Since only the electrons with high energy $E$ ($E > Q$, $Q$ is the threshold energy of inverse $\beta-$decay) at large Landau levels can…

High Energy Astrophysical Phenomena · Physics 2013-12-11 Z. F. Gao , N. Wang , J. P. Yuan , L. Jiang , D. L. Song

The calculation results of solar neutrino capture cross-section on the $^{76}Ge$ nucleus are presented. The charge-exchange strength function $S(E)$ was obtained from the experiment data in the $ ^{76}Ge(^{3}He, t)^{76}As $ reaction. The…

Radiative capture of protons is investigated as a probe of clustering in nuclei far from stability. The first such measurement on a halo nucleus is reported here for the reaction $^6$He(p,$\gamma$) at 40 MeV. Capture into $^7$Li is observed…

Nuclear Experiment · Physics 2009-11-07 E. Sauvan , F. M. Marqués , H. W. Wilschut , N. A. Orr

We study Gamow-Teller strength distributions in some selected nuclei of particular Astrophysical interest within the iron mass region. The theoretical framework is based on a proton-neutron Quasiparticle Random Phase Approximation built on…

Nuclear Theory · Physics 2009-11-10 P. Sarriguren , E. Moya de Guerra , R. Alvarez-Rodriguez

Lepton (electron and positron) capture rates on iron-regime nuclei are an essential element for modeling the late stages in the evolution of massive stars that end as core-collapse and thermonuclear supernovae. Previous simulation studies…

Nuclear Theory · Physics 2025-04-15 Ramoona Shehzadi , Jameel-Un Nabi , Fakeha Farooq

The neutron capture cross section of 26Mg was measured relative to the known gold cross section at thermonuclear energies using the fast cyclic activation technique. The experiment was performed at the 3.75 MV Van-de-Graaff accelerator,…

Nuclear Experiment · Physics 2008-11-26 P. Mohr , H. Beer , H. Oberhummer , G. Staudt