Production of light elements on a low-mass secondary in a soft X-ray transient

Journal Article · Wed May 21 04:00:00 EDT 2008 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2943613· OSTI ID:21143498

Fujimoto, Shin-ichiro ^[1]; Matsuba, Ryuichi; Arai, Kenzo ^[2]

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1. Kumamoto National College of Technology, Kumamoto 861-1102 (Japan)
2. Kumamoto University, Kumamoto 860-8555 (Japan)

We examine production of light elements (Li, Be, and B) on the surface of a low-mass secondary in a black hole soft X-ray transient (BHSXT) through the spallation of CNO nuclei by neutrons which are ejected from a hot (>10 MeV) advection-dominated accretion flow (ADAF) around the black hole. Using updated binary parameters, cross sections of neutron-induced spallation reactions, and mass accretion rates in ADAFs derived from the spectrum fitting of multi-wavelength observations of quiescent BHSXTs, we obtain the equilibrium abundances of Li by equating the production rate of Li and the mass transfer rate through accretion to the black hole. We find that the resulting abundances are found to be in good agreement with the observed values in seven BHSXTs. Moreover, the isotopic ratio {sup 6}Li/{sup 7}Li and the abundance ratios Be/Li and B/Li are calculated to be about 0.7-0.8, 1.0-1.3, and 1.8-2.1, respectively, on the secondaries.

• OSTI ID: 21143498
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1016; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ACCRETION DISKS
ASTROPHYSICS
BLACK HOLES
BORON ISOTOPES
CNO CYCLE
CROSS SECTIONS
ELEMENT ABUNDANCE
ISOTOPE RATIO
LITHIUM 6
LITHIUM 7
MEV RANGE
NEUTRON REACTIONS
NUCLEAR REACTION YIELD
NUCLEOSYNTHESIS
SOFT X RADIATION
SPALLATION
TRANSIENTS