Continuum shell model Continuum shell model calculations for calculations for nucleon capture at nucleon capture at astrophysical energies astrophysical energies Janina Grinevi Janina Grinevi ciute ciute Western Michigan University Western Michigan University
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Continuum shell model calculations for nucleon capture at astrophysical energies
Continuum shell model calculations for nucleon capture at astrophysical energies. Janina Grinevi ciute Western Michigan University. H burning pp chain. 7 Be(p, ) 8 B. Production rate of 8 Be solar neutrinos: accuracy of stellar models neutrino mixing and nature of weak interaction - PowerPoint PPT Presentation
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Continuum shell model Continuum shell model calculations for nucleon capture calculations for nucleon capture
at astrophysical energiesat astrophysical energies
Janina GrineviJanina Grineviciuteciute
Western Michigan UniversityWestern Michigan University
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H burningH burning pp chain pp chain
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77Be(p,Be(p,))88B B
Production rate of Production rate of 88Be solar neutrinos:Be solar neutrinos:• accuracy of stellar modelsaccuracy of stellar models• neutrino mixing and nature of weak neutrino mixing and nature of weak
interactioninteraction
desired reaction rate uncertainty less desired reaction rate uncertainty less than 5%than 5%
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Dependance on temperature of energy production ratesDependance on temperature of energy production rates
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CNO cycleCNO cycle
figure taken from H. Schatz (2004)figure taken from H. Schatz (2004)
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4 CNO cycles4 CNO cycles
figure taken from H. Schatz (2004)figure taken from H. Schatz (2004)
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1414N(p,N(p,))1515O O
Slowest reaction in CNO cycleSlowest reaction in CNO cycle• controls duration of hydrogen burningcontrols duration of hydrogen burning• determines main sequence turnoff – determines main sequence turnoff –
globular cluster agesglobular cluster ages• determines CNO neutrino flux in the Sundetermines CNO neutrino flux in the Sun
Initial abundance of C, N,O is mostly Initial abundance of C, N,O is mostly converted into converted into 1414NN
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Turn off luminosity – age of globular clustersTurn off luminosity – age of globular clusters
CNO cycle
pp chain
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Proton capture reactionsProton capture reactions
Crossections are extremely low Crossections are extremely low
measure as low in energy as measure as low in energy as possible, thenpossible, then extrapolate to Gamow window