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Related papers: Lithium-6 from Solar Flares

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We briefly review the theory of gamma ray production in solar flares and present the highlights of the observations and their implications. Specifically: (i) the gamma ray data show that a large fraction of the released flare energy is in…

Astrophysics · Physics 2007-05-23 Reuven Ramaty , Natalie Mandzhavidze

The high 6-Li abundances recently measured in metal-poor halo stars are far above the value predicted by Big Bang nucleosynthesis. They cannot be explained by galactic cosmic-ray interactions in the interstellar medium either. Various…

Astrophysics · Physics 2009-11-11 V. Tatischeff , J. -P. Thibaud

Motivated by the recent report of a $^6$Li detection in the atmosphere of HD~84937, we couple stellar evolution calculations with light isotope production via stellar flares. We find that as a consequence of their small convective envelope…

Astrophysics · Physics 2009-10-22 C. P. Deliyannis , R. A. Malaney

The relative abundance of deuterium (D) in the solar atmosphere is not known. D is not only destroyed in stars, it is also synthesized in the atmospheres of active stars (Prodanovic & Fields 2003). In several cases, production of D in the…

Instrumentation and Methods for Astrophysics · Physics 2009-09-08 Frank Scherb

The lines of lithium at 6708 A, and 6103 A, are analyzed in high resolution spectra of some sharp-lined and slowly rotating roAp stars. Three spectral synthesis codes - STARSP, ZEEMAN2 and SYNTHM were used. New lines of the rare earth…

We study the synthesis of lithium isotopes in the hot tori formed around stellar mass black holes by accretion of the companion star. We find that sizable amounts of both stable isotopes 6Li and 7Li can be produced, the exact figures…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-19 Fabio Iocco , Miguel Pato

The rare isotope 6Li is made only by cosmic rays, dominantly in alpha+alpha fusion reactions with ISM helium. Consequently, this nuclide provides a unique diagnostic of the history of cosmic rays in our Galaxy. The same hadronic cosmic-ray…

Astrophysics · Physics 2016-08-30 Brian D. Fields , Tijana Prodanovic

Cross sections for production of 6He, 6Li, 7Li, and 7Be in the alpha+alpha reaction were measured at bombarding energies of 159.3, 279.6, and 619.8 MeV, and are found to decrease rapidly with increasing energy. These cross sections are…

During the Big Bang, ${}^{6}{\rm Li}$ was synthesized via the ${}^{2}{\rm H}(\alpha,\gamma){}^{6}{\rm Li}$ reaction. After almost 25 years of the failed attempts to measure the ${}^{2}{\rm H}(\alpha,\gamma){}^{6}{\rm Li}$ reaction in the…

Nuclear Theory · Physics 2016-05-04 A. M. Mukhamedzhanov , Shubhchintak , C. A. Bertulani

Nuclear interactions of ions accelerated at the surface of flaring stars can produce fresh isotopes in stellar atmospheres. Although this nucleosynthesis is not significant for the chemical evolution of the Galaxy, it can be important for a…

Astrophysics · Physics 2008-01-14 V. Tatischeff , J. -P. Thibaud , I. Ribas

The primordial abundances of Deuterium, he4, and li7 are crucial to determination of the baryon density of the Universe in the framework of standard Big Bang nucleosynthesis (BBN). li6 which is only produced in tiny quantities and it is…

We calculate the production rates of Li6, Li7, Be9, B10 and B11 via spallation of Carbon, Nitrogen and Oxygen nuclei by protons and alpha-particles and by alpha-alpha fusion reactions. We include recent measurements of the cross sections of…

Astrophysics · Physics 2007-05-23 J. P. Kneller , J. R. Phillips , T. P. Walker

This study focuses on a fuel cell composed of Lithium Deuteride (LiD) in a spherical geometry, in which isotropic monoenergetic neutrons of 0.025 eV (thermal neutrons) are generated at the center. The objective is to investigate the…

Instrumentation and Detectors · Physics 2025-03-14 Serena Fattori , Rino Persiani , Ugo Abundo

Cosmic structure formation leads to large-scale shocked baryonic flows which are expected to produce a cosmological population of structure-formation cosmic rays (SFCRs). Interactions between SFCRs and ambient baryons will produce lithium…

Astrophysics · Physics 2008-11-26 Tijana Prodanovic , Brian D. Fields

Lithium is an excellent tracer of mixing in stars as it is destroyed (by nuclear reactions) at a temperature around $\sim 2.5\times 10^6$ K. The lithium destruction zone is typically located in the radiative region of a star. If the…

Astrophysics · Physics 2007-05-23 Brian Chaboyer

The hydrogen Lyman-$\alpha$ (H {\sc i} Ly$\alpha$) emission during solar flares has rarely been studied in spatially resolved images and its physical origin has not been fully understood. In this paper, we present novel Ly$\alpha$ images…

Solar and Stellar Astrophysics · Physics 2022-09-21 Ying Li , Qiao Li , De-Chao Song , Andrea Francesco Battaglia , Hualin Xiao , Säm Krucker , Udo Schühle , Hui Li , Weiqun Gan , M. D. Ding

Solar flares involve complex processes that are coupled and span a wide range of temporal, spatial, and energy scales. Modeling such processes self-consistently has been a challenge in the past. Here we present results from simulations that…

Solar and Stellar Astrophysics · Physics 2015-11-18 Fatima Rubio da Costa , Wei Liu , Vahe' Petrosian , Mats Carlsson

Spectroscopic observations of metal-poor stars have indicated possible 6Li abundances that are much larger than the primordial abundance predicted in the standard big bang nucleosynthesis model. Possible mechanisms of 6Li production in…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-21 Motohiko Kusakabe , Masahiro Kawasaki

I consider the synthesis of 6Li due to the decay of relic particles, such as gravitinos or moduli, after the epoch of Big Bang Nucleosynthesis. The synthesized 6Li/H ratio may be compared to 6Li/H in metal-poor stars which, in the absence…

Astrophysics · Physics 2009-10-31 K. Jedamzik

In previous works we have developed a method to convert solar X-ray data, collected with the Yohkoh/SXT, into templates of stellar coronal observations. Here we apply the method to several solar flares, for comparison with stellar X-ray…

Astrophysics · Physics 2009-11-06 F. Reale , G. Peres , S. Orlando
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