Hints for neutrino-process boron in presolar silicon carbide grains from supernovae

Wataru Fujiya, Peter Hoppe, U. Ott

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

We have studied more than 1000 presolar silicon carbide (SiC) grains from the Murchison CM2 chondrite for C- and Si-isotopic compositions. Twelve SiC X grains, characterized by strong enrichments in 28Si and believed to originate from Type II Supernovae (SNeII), were also measured for Li- and B-isotopic compositions. None of these grains show resolvable isotope anomalies in Li or B. For the seven X grains without Li and B contributions from nearby or attached SiC grains of distinct origins we find on average 7Li/ 6Li = 11.83 0.29 (solar system: 12.06) and 11B/ 10B = 4.68 0.31 (solar system: 4.03). The average 7Li/6Li is compatible with the solar system ratio and the lithium in the X grains is likely largely dominated by contaminating Li of laboratory or meteoritic origin. Also, most of the boron in X grains appears to be contamination but the small 11B excess of 16%, significant at the 2σ level, can be considered a hint for the presence of boron produced by the neutrino process in the parent SNeII. Despite this finding, a quantitative comparison of the B isotope and abundance data of X grains with model predictions reveals deficiencies in our current understanding of the details of B production in SNeII as well as on B chemistry and condensation in SNII ejecta.

Original languageEnglish
Article numberL7
JournalAstrophysical Journal Letters
Volume730
Issue number1 PART II
DOIs
Publication statusPublished - Mar 20 2011

Fingerprint

boron
silicon carbides
silicon
supernovae
neutrinos
solar system
isotopic composition
isotope
lithium
ejecta
chondrite
condensation
anomaly
isotopes
prediction
chondrites
contamination
chemistry
anomalies
predictions

Keywords

  • circumstellar matter
  • nuclear reactions: nucleosynthesis: abundances
  • supernovae: general

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Hints for neutrino-process boron in presolar silicon carbide grains from supernovae. / Fujiya, Wataru; Hoppe, Peter; Ott, U.

In: Astrophysical Journal Letters, Vol. 730, No. 1 PART II, L7, 20.03.2011.

Research output: Contribution to journalArticle

@article{b0df3c4e49554568b92d0ab46aed3a91,
title = "Hints for neutrino-process boron in presolar silicon carbide grains from supernovae",
abstract = "We have studied more than 1000 presolar silicon carbide (SiC) grains from the Murchison CM2 chondrite for C- and Si-isotopic compositions. Twelve SiC X grains, characterized by strong enrichments in 28Si and believed to originate from Type II Supernovae (SNeII), were also measured for Li- and B-isotopic compositions. None of these grains show resolvable isotope anomalies in Li or B. For the seven X grains without Li and B contributions from nearby or attached SiC grains of distinct origins we find on average 7Li/ 6Li = 11.83 0.29 (solar system: 12.06) and 11B/ 10B = 4.68 0.31 (solar system: 4.03). The average 7Li/6Li is compatible with the solar system ratio and the lithium in the X grains is likely largely dominated by contaminating Li of laboratory or meteoritic origin. Also, most of the boron in X grains appears to be contamination but the small 11B excess of 16{\%}, significant at the 2σ level, can be considered a hint for the presence of boron produced by the neutrino process in the parent SNeII. Despite this finding, a quantitative comparison of the B isotope and abundance data of X grains with model predictions reveals deficiencies in our current understanding of the details of B production in SNeII as well as on B chemistry and condensation in SNII ejecta.",
keywords = "circumstellar matter, nuclear reactions: nucleosynthesis: abundances, supernovae: general",
author = "Wataru Fujiya and Peter Hoppe and U. Ott",
year = "2011",
month = "3",
day = "20",
doi = "10.1088/2041-8205/730/1/L7",
language = "English",
volume = "730",
journal = "Astrophysical Journal Letters",
issn = "2041-8205",
publisher = "IOP Publishing Ltd.",
number = "1 PART II",

}

TY - JOUR

T1 - Hints for neutrino-process boron in presolar silicon carbide grains from supernovae

AU - Fujiya, Wataru

AU - Hoppe, Peter

AU - Ott, U.

PY - 2011/3/20

Y1 - 2011/3/20

N2 - We have studied more than 1000 presolar silicon carbide (SiC) grains from the Murchison CM2 chondrite for C- and Si-isotopic compositions. Twelve SiC X grains, characterized by strong enrichments in 28Si and believed to originate from Type II Supernovae (SNeII), were also measured for Li- and B-isotopic compositions. None of these grains show resolvable isotope anomalies in Li or B. For the seven X grains without Li and B contributions from nearby or attached SiC grains of distinct origins we find on average 7Li/ 6Li = 11.83 0.29 (solar system: 12.06) and 11B/ 10B = 4.68 0.31 (solar system: 4.03). The average 7Li/6Li is compatible with the solar system ratio and the lithium in the X grains is likely largely dominated by contaminating Li of laboratory or meteoritic origin. Also, most of the boron in X grains appears to be contamination but the small 11B excess of 16%, significant at the 2σ level, can be considered a hint for the presence of boron produced by the neutrino process in the parent SNeII. Despite this finding, a quantitative comparison of the B isotope and abundance data of X grains with model predictions reveals deficiencies in our current understanding of the details of B production in SNeII as well as on B chemistry and condensation in SNII ejecta.

AB - We have studied more than 1000 presolar silicon carbide (SiC) grains from the Murchison CM2 chondrite for C- and Si-isotopic compositions. Twelve SiC X grains, characterized by strong enrichments in 28Si and believed to originate from Type II Supernovae (SNeII), were also measured for Li- and B-isotopic compositions. None of these grains show resolvable isotope anomalies in Li or B. For the seven X grains without Li and B contributions from nearby or attached SiC grains of distinct origins we find on average 7Li/ 6Li = 11.83 0.29 (solar system: 12.06) and 11B/ 10B = 4.68 0.31 (solar system: 4.03). The average 7Li/6Li is compatible with the solar system ratio and the lithium in the X grains is likely largely dominated by contaminating Li of laboratory or meteoritic origin. Also, most of the boron in X grains appears to be contamination but the small 11B excess of 16%, significant at the 2σ level, can be considered a hint for the presence of boron produced by the neutrino process in the parent SNeII. Despite this finding, a quantitative comparison of the B isotope and abundance data of X grains with model predictions reveals deficiencies in our current understanding of the details of B production in SNeII as well as on B chemistry and condensation in SNII ejecta.

KW - circumstellar matter

KW - nuclear reactions: nucleosynthesis: abundances

KW - supernovae: general

UR - http://www.scopus.com/inward/record.url?scp=79953670273&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=79953670273&partnerID=8YFLogxK

U2 - 10.1088/2041-8205/730/1/L7

DO - 10.1088/2041-8205/730/1/L7

M3 - Article

AN - SCOPUS:79953670273

VL - 730

JO - Astrophysical Journal Letters

JF - Astrophysical Journal Letters

SN - 2041-8205

IS - 1 PART II

M1 - L7

ER -