- Email: [email protected]
Thermal neutrinos from pre-supernova
Available online at www.sciencedirect.com
Nuclear Physics B (Proc. Suppl.) 221 (2011) 380 www.elsevier.com/locate/npbps
Thermal neutrinos from pre-supernova A. Odrzywolek1 , M. Misiaszek1 , M. Kutschera1,2 1 2
M. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, Cracov, Poland H. Niewodniczanski Institute of Nuclear Physics, PAS, Radzikowskiego 152, Cracov, Poland
E-mail: [email protected] Abstract. We would like to discuss prospects for neutrino observations of the core-collapse supernova progenitor during neutrino-cooled stage. We will present new theoretical results on thermal neutrino and antineutrino spectra produced deep inside the pre-supernova core. Three competing processes: pair-, photo and plasma-neutrino production, are taken into account. The results will be used to estimate signal in existing and future neutrino detectors. Chance for supernova prediction is estimated, with possible aid to core-collapse neutrino and gravitational wave detectors in the form of early warning.
In our short contribution we would like to answer some comments and questions asked during poster session [1]. Two days of the silicon burning with Lν = 3 × 1045 erg/s quoted in [2] was randomly chosen typical example model [3]. Duration of the Si burning depends on evolutionary track of the massive star, particularly mass of the Si core at the onset of the ignition. Total average neutrino luminosity Lν depends on (1) the burning time τSi and (2) amount of fuel (Si core mass MSi MFe ): Lν = MFe ΔEb /τSi . (1) ΔEb is the nuclear binding energy difference between fuel (”Si”) and ash (”Fe”). From evolutionary calculations of [4] we get core mass in the range 1.2 . . . 1.65 M and τSi from 18 days to 17 hours, respectively. Therefore Lν vary from 3.1 × 1044 to 9.8 × 1045 erg/s. Electron antineutrinos from pair-annihilation are of particular interest [5]. One can quickly estimate fraction of given flavor from the following: (1) reaction rate is proportional to 2 ), where mass term was dropped (2) number squared matrix element M 2 ∼ 8G2F (CV2 + CA of emitted neutrinos and antineutrinos is equal. Therefore, rate of the reaction rates is e 2 )/(C μ,τ 2 + C μ,τ 2 ) = 4.5. Total neutrino flux is: F Re /Rμ,τ (CVe 2 + CA tot = 2Re + 4Rμ,τ = V A (2 + 4/4.5)Re = 2.9Re . Finally Fν¯e /Ftot 0.35 ∼ 1/3, i.e. about one third is emitted as electron antineutrinos. This statement may be altered by the neutrino oscillations. Acknowledgments Supported by grant of Polish Ministry of Science and Higher Education No. 1 P03D 005 28. References [1] [2] [3] [4] [5]
http://ribes.if.uj.edu.pl/poster/PosterA0.pdf Odrzywolek A, Misiaszek M, Kutschera M 2004 Astropart. Phys. 21 303-313 Weaver T A, Zimmerman G B, Woosley S E, 1978, ApJ 225 1021 Woosley S E, Heger A, Weaver T A 2002 Rev. Mod. Phys. 74 1015 Beacom J F, Vagins M R 2004 PRL 93 171101
0920-5632/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.nuclphysbps.2011.10.029
Nuclear Physics B (Proc. Suppl.) 221 (2011) 380 www.elsevier.com/locate/npbps
Thermal neutrinos from pre-supernova A. Odrzywolek1 , M. Misiaszek1 , M. Kutschera1,2 1 2
M. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, Cracov, Poland H. Niewodniczanski Institute of Nuclear Physics, PAS, Radzikowskiego 152, Cracov, Poland
E-mail: [email protected] Abstract. We would like to discuss prospects for neutrino observations of the core-collapse supernova progenitor during neutrino-cooled stage. We will present new theoretical results on thermal neutrino and antineutrino spectra produced deep inside the pre-supernova core. Three competing processes: pair-, photo and plasma-neutrino production, are taken into account. The results will be used to estimate signal in existing and future neutrino detectors. Chance for supernova prediction is estimated, with possible aid to core-collapse neutrino and gravitational wave detectors in the form of early warning.
In our short contribution we would like to answer some comments and questions asked during poster session [1]. Two days of the silicon burning with Lν = 3 × 1045 erg/s quoted in [2] was randomly chosen typical example model [3]. Duration of the Si burning depends on evolutionary track of the massive star, particularly mass of the Si core at the onset of the ignition. Total average neutrino luminosity Lν depends on (1) the burning time τSi and (2) amount of fuel (Si core mass MSi MFe ): Lν = MFe ΔEb /τSi . (1) ΔEb is the nuclear binding energy difference between fuel (”Si”) and ash (”Fe”). From evolutionary calculations of [4] we get core mass in the range 1.2 . . . 1.65 M and τSi from 18 days to 17 hours, respectively. Therefore Lν vary from 3.1 × 1044 to 9.8 × 1045 erg/s. Electron antineutrinos from pair-annihilation are of particular interest [5]. One can quickly estimate fraction of given flavor from the following: (1) reaction rate is proportional to 2 ), where mass term was dropped (2) number squared matrix element M 2 ∼ 8G2F (CV2 + CA of emitted neutrinos and antineutrinos is equal. Therefore, rate of the reaction rates is e 2 )/(C μ,τ 2 + C μ,τ 2 ) = 4.5. Total neutrino flux is: F Re /Rμ,τ (CVe 2 + CA tot = 2Re + 4Rμ,τ = V A (2 + 4/4.5)Re = 2.9Re . Finally Fν¯e /Ftot 0.35 ∼ 1/3, i.e. about one third is emitted as electron antineutrinos. This statement may be altered by the neutrino oscillations. Acknowledgments Supported by grant of Polish Ministry of Science and Higher Education No. 1 P03D 005 28. References [1] [2] [3] [4] [5]
http://ribes.if.uj.edu.pl/poster/PosterA0.pdf Odrzywolek A, Misiaszek M, Kutschera M 2004 Astropart. Phys. 21 303-313 Weaver T A, Zimmerman G B, Woosley S E, 1978, ApJ 225 1021 Woosley S E, Heger A, Weaver T A 2002 Rev. Mod. Phys. 74 1015 Beacom J F, Vagins M R 2004 PRL 93 171101
0920-5632/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.nuclphysbps.2011.10.029