Reaction rate uncertainties: NeNa and MgAl in AGB stars

Robert G. Izzard; Maria Lugaro; Christian Iliadis; Amanda Karakas

Reaction rate uncertainties: NeNa and MgAl in AGB stars

Robert G. Izzard, Maria Lugaro, Christian Iliadis, Amanda Karakas

Research output: Contribution to journal › Conference article › Research › peer-review

Abstract

We study the effect of uncertainties in the proton-capture reaction rates of the NeNa and MgAl chains on nucleosynthesis due to the operation of hot bottom burning (HBB) in intermediate-mass asymptotic giant branch (AGB) stars. HBB nucleosynthesis is associated with the production of sodium, radioactive ²⁶Al and the heavy magnesium isotopes, and it is possibly responsible for the O, Na, Mg and Al abundance anomalies observed in globular cluster stars. We model HBB with an analytic code based on full stellar evolution models so we can quickly cover a large parameter space. The reaction rates are varied first individually, then all together. This creates a knock-on effect, where an increase of one reaction rate affects production of an isotope further down the reaction chain. We find the yields of ²²Ne, ²³Na and ²⁶Al to be the most susceptible to current nuclear reaction rate uncertainties.

Original language	English
Journal	Proceedings of Science
Publication status	Published - 1 Dec 2006
Externally published	Yes
Event	International Symposium on Nuclei in the Cosmos 2006 - Geneva, Switzerland Duration: 25 Jun 2006 → 30 Jun 2006 Conference number: 9th

Cite this

@article{01a214cb16fd4d06970b5d46e2604956,

title = "Reaction rate uncertainties: NeNa and MgAl in AGB stars",

abstract = "We study the effect of uncertainties in the proton-capture reaction rates of the NeNa and MgAl chains on nucleosynthesis due to the operation of hot bottom burning (HBB) in intermediate-mass asymptotic giant branch (AGB) stars. HBB nucleosynthesis is associated with the production of sodium, radioactive 26Al and the heavy magnesium isotopes, and it is possibly responsible for the O, Na, Mg and Al abundance anomalies observed in globular cluster stars. We model HBB with an analytic code based on full stellar evolution models so we can quickly cover a large parameter space. The reaction rates are varied first individually, then all together. This creates a knock-on effect, where an increase of one reaction rate affects production of an isotope further down the reaction chain. We find the yields of 22Ne, 23Na and 26Al to be the most susceptible to current nuclear reaction rate uncertainties.",

author = "Izzard, {Robert G.} and Maria Lugaro and Christian Iliadis and Amanda Karakas",

year = "2006",

month = dec,

day = "1",

language = "English",

journal = "Proceedings of Science",

issn = "1824-8039",

publisher = "Sissa Medialab, SRL",

note = "International Symposium on Nuclei in the Cosmos 2006, NIC 2006 ; Conference date: 25-06-2006 Through 30-06-2006",

}

TY - JOUR

T1 - Reaction rate uncertainties

T2 - International Symposium on Nuclei in the Cosmos 2006

AU - Izzard, Robert G.

AU - Lugaro, Maria

AU - Iliadis, Christian

AU - Karakas, Amanda

N1 - Conference code: 9th

PY - 2006/12/1

Y1 - 2006/12/1

N2 - We study the effect of uncertainties in the proton-capture reaction rates of the NeNa and MgAl chains on nucleosynthesis due to the operation of hot bottom burning (HBB) in intermediate-mass asymptotic giant branch (AGB) stars. HBB nucleosynthesis is associated with the production of sodium, radioactive 26Al and the heavy magnesium isotopes, and it is possibly responsible for the O, Na, Mg and Al abundance anomalies observed in globular cluster stars. We model HBB with an analytic code based on full stellar evolution models so we can quickly cover a large parameter space. The reaction rates are varied first individually, then all together. This creates a knock-on effect, where an increase of one reaction rate affects production of an isotope further down the reaction chain. We find the yields of 22Ne, 23Na and 26Al to be the most susceptible to current nuclear reaction rate uncertainties.

AB - We study the effect of uncertainties in the proton-capture reaction rates of the NeNa and MgAl chains on nucleosynthesis due to the operation of hot bottom burning (HBB) in intermediate-mass asymptotic giant branch (AGB) stars. HBB nucleosynthesis is associated with the production of sodium, radioactive 26Al and the heavy magnesium isotopes, and it is possibly responsible for the O, Na, Mg and Al abundance anomalies observed in globular cluster stars. We model HBB with an analytic code based on full stellar evolution models so we can quickly cover a large parameter space. The reaction rates are varied first individually, then all together. This creates a knock-on effect, where an increase of one reaction rate affects production of an isotope further down the reaction chain. We find the yields of 22Ne, 23Na and 26Al to be the most susceptible to current nuclear reaction rate uncertainties.

UR - http://www.scopus.com/inward/record.url?scp=84887481374&partnerID=8YFLogxK

M3 - Conference article

AN - SCOPUS:84887481374

JO - Proceedings of Science

JF - Proceedings of Science

SN - 1824-8039

Y2 - 25 June 2006 through 30 June 2006

ER -

Reaction rate uncertainties: NeNa and MgAl in AGB stars

Abstract

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