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Related papers: Calcium Excess in Novae: Beyond Nuclear Physics Un…

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Explosive nuclear burning in astrophysical environments produces unstable nuclei which again can be targets for subsequent reactions. In addition, it involves a large number of stable nuclides which are not fully explored by experiments,…

Nuclear Theory · Physics 2017-08-23 T. Rauscher , C. Froehlich , K. H. Guber

Context. Monte Carlo methods can be used to evaluate the uncertainty of a reaction rate that arises from many uncertain nuclear inputs. However, until now no attempt has been made to find the effect of correlated energy uncertainties in…

Instrumentation and Methods for Astrophysics · Physics 2020-10-07 Richard Longland , Nicolas de Séréville

The impact of nuclear mass uncertainties on the \emph{r}-process abundances has been systematically studied with the classical \emph{r}-process model by varying the mass of every individual nucleus in the range of $\pm0.1$ to $\pm3.0\…

Nuclear Theory · Physics 2021-07-05 Xiao-Fei Jiang , Xin-Hui Wu , Peng-Wei Zhao

The main s-process taking place in low mass stars produces about half of the elements heavier than iron. It is therefore very important to determine the importance and impact of nuclear physics uncertainties on this process. We have…

Solar and Stellar Astrophysics · Physics 2018-06-28 G. Cescutti , R. Hirschi , N. Nishimura , J. W. den Hartogh , T. Rauscher , A. St. J. Murphy , S. Cristallo

Nuclear uncertainties in the production of $p$ nuclei in massive stars have been quantified in a Monte Carlo procedure. Bespoke temperature-dependent uncertainties were assigned to different types of reactions involving nuclei from Fe to…

High Energy Astrophysical Phenomena · Physics 2016-10-14 T. Rauscher , N. Nishimura , R. Hirschi , G. Cescutti , A. St. J. Murphy , A. Heger

The majority of nuclear reactions in astrophysics involve unstable nuclei which are not fully accessible by experiments yet. Therefore, there is high demand for reliable predictions of cross sections and reaction rates by theoretical means.…

Astrophysics · Physics 2010-12-13 T. Rauscher , R. D. Hoffman , S. E. Woosley , F. -K. Thielemann

Classical novae are thermonuclear explosions that take place in the envelopes of accreting white dwarfs in binary systems. The material piles up under degenerate conditions, driving a thermonuclear runaway. The energy released by the suite…

Solar and Stellar Astrophysics · Physics 2016-06-29 Jordi Casanova , Jordi Jose , Enrique Garcia-Berro , Steven N. Shore

Classical novae are among the most frequent transient events in the Milky Way, and key agents of ongoing nucleosynthesis. Despite their large numbers, they have never been observed in soft $\gamma$-ray emission. Measurements of their…

High Energy Astrophysical Phenomena · Physics 2021-06-30 Thomas Siegert , Sohan Ghosh , Kalp Mathur , Ethan Spraggon , Akshay Yeddanapudi

The 33S(p,\gamma)34Cl reaction is important for constraining predictions of certain isotopic abundances in oxygen-neon novae. Models currently predict as much as 150 times the solar abundance of 33S in oxygen-neon nova ejecta. This…

It is demonstrated using Monte Carlo simulation that in different nucleus$-$nucleus collision samples, the increase of the fluctuation of event factorial moments with decreasing phase space scale, called erraticity, is still dominated by…

High Energy Physics - Phenomenology · Physics 2009-11-07 Liu Fuming , Liao Hongbo , Liu Ming , Liu Feng , Liu Lianshou

Core-collapse supernovae, occurring at the end of massive star evolution, produce heavy elements, including those in the iron peak. Although the explosion mechanism is not yet fully understood, theoretical models can reproduce optical…

Solar and Stellar Astrophysics · Physics 2026-02-24 Nobuya Nishimura , Carla Froehlich , Thomas Rauscher

We have investigated the abundance of calcium in early-type galaxies by measuring the strength of the Ca I 4227 absorption line in their integrated spectra. The database used is the large sample of early-type galaxy integrated spectra in…

Astrophysics · Physics 2016-08-30 L. C. Prochaska , James A. Rose , Ricardo P. Schiavon

Calcium abundance in the atmosphere of Am stars is examined as a function of their evolutionary state within the main sequence. New spectroscopic abundances as well as abundances abtained photometrically by Guthrie (1987) are used, since…

Astrophysics · Physics 2007-05-23 M. Kunzli , P. North

Classical novae are fascinating stellar events, at the crossroads of astrophysics, nuclear physics and cosmochemistry. In this review, we outline the history of nova modeling with special emphasis on recent advances and perspectives in…

Astrophysics · Physics 2009-11-10 Jordi Jose

Rigorous statistical methods for estimating thermonuclear reaction rates and nucleosynthesis are becoming increasingly established in nuclear astrophysics. The main challenge being faced is that experimental reaction rates are highly…

Nuclear Experiment · Physics 2015-06-22 Christian Iliadis , Richard Longland , Alain Coc , F. X. Timmes , Art E. Champagne

Recent spectroscopic measurements of the equivalent widths of the resonant Be II doublet and Ca II K lines and their ratios in expanding nova ejecta indicate surprisingly high abundances of $^7$Be with a typical mass fraction…

Solar and Stellar Astrophysics · Physics 2020-12-02 Pavel A. Denissenkov , Chris Ruiz , Sriteja Upadhyayula , Falk Herwig

Neutrino-driven ejecta in core collapse supernovae (CCSNe) offer an interesting astrophysical scenario where lighter heavy elements between Sr and Ag can be synthesized. Previous studies emphasized the important role that ($\alpha,n$)…

Nuclear Experiment · Physics 2020-06-10 J. Bliss , A. Arcones , F. Montes , J. Pereira

Type-I X-ray bursts can be used to determine properties of accreting neutron stars via comparisons between model calculations and astronomical observations, exploiting the sensitivity of models to astrophysical conditions. However, the…

High Energy Astrophysical Phenomena · Physics 2019-02-19 Zach Meisel , Grant Merz , Sophia Medvid

Detailed nucleosynthesis in the ejecta of classical novae has been determined for a grid of hydrodynamic nova models. The reported 14 evolutionary sequences, followed from the onset of accretion up to the explosion and ejection stages, span…

Astrophysics · Physics 2008-11-26 Jordi Jose , Margarita Hernanz

We investigated the impact of uncertainties in neutron-capture and weak reactions (on heavy elements) on the s-process nucleosynthesis in low-mass stars using a Monte-Carlo based approach. We performed extensive nuclear reaction network…

Solar and Stellar Astrophysics · Physics 2020-01-08 G. Cescutti , R. Hirschi , N. Nishimura , T. Rauscher , J. den Hartogh , A. St. J. Murphy , S. Cristallo