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Gravitational collapse of stellar cores and Supernovae (neutrino fluxes and shock waves)

Gravitational collapse of stellar cores and Supernovae (neutrino fluxes and shock waves). D.K. Nadyozhin. Institute for Theoretical and Experimental Physics ITEP, Moscow, Russia. 23rd European Cosmic Ray Symposium Moscow, Russia, July, 3 - 7 , 2012.

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Gravitational collapse of stellar cores and Supernovae (neutrino fluxes and shock waves)

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  1. Gravitational collapse of stellar cores and Supernovae (neutrino fluxes and shock waves) D.K. Nadyozhin Institute for Theoretical and Experimental Physics ITEP, Moscow, Russia 23rd European Cosmic Ray Symposium Moscow, Russia, July, 3-7, 2012

  2. Core-collapse SNe (all other Types but Ia) The SN outburst is triggered by the gravitational collapse of the “iron” core of a mass MFe=(1.22) Minto a neutron star. About (1015)% MFec2is radiated in the form of neutrinos and antineutrinos of all the flavors (e, , ): The explosion energy (kinetic energy of the envelope expansion): Eexp = (0.52)1051erg it comes from the shock wave created at the boundary between a new-born neutron star and the envelope to be expelled. Rich nucleosynthesis — from neutrino-induced creation of light element in C-O and He shells through synthesis of heavy nuclides by neutron capture at the bottom of expelled envelope

  3. Neutrino from collapsing stellar cores Nonthermal e The cumulative neutrino light curve (based on Nadyozhin 1978)

  4. Characteristic time of the neutrino light curve tail  1020 s

  5. Nonthermal component: the sharp peak comes from nonequilibrium neutronization of stellar matter Mostly electron neutrinos νe of individual energy: • 15-20 MeV for spherically-symmetrical collapse • 30-40 MeV for rotational-fission model is necessary to interpret the statistically significant signal from SN 1987A registered by the LSD neutrino detector Characteristic duration of the peak < 0.5 s About of 10% of total is radiated in the peak

  6. adapted from A.G. Aksenov et al. Astronomy Letters 23, No. 6 (1997)

  7. SN «visible» ejecta 1.2 ly Circumstellar Ring SN 1987A 16 years old (HST Nov. 28, 2003) Interaction of shock wave with the circumstellar ring

  8. January 2005 Chandra X-ray 0.4–0.7 keV Observation Time 8 hours HST Optical

  9. B. Leibundgut 16th Workshop on Nuclear Astrophysics, Ringberg Castle, Germany, March 26-30, 2012 http://www.mpa-garching.mpg.de/Hydro/NucAstro/prog12.html

  10. Results of obsevations Central dust cloud has a form of a prolate ellipsoid with the axis ratio about 2.5. The ellipsoid lays in the plane of equatorial ring and expands with the velocity of ~3000 km/s. The dust is heated by X-rays from the ring and by the decay of Ti44 and radiates in far infrared. Central stellar remnant is not yet seen being screened by the dust.

  11. Interaction of supernova ejecta with circumstellar medium R ~ t,   0.50.9 Nadyozhin (1981, 1985), Chevalier (1982)

  12. Conclusion The neutrino detectors capable to separate the contributions from different types of neutrino in the registered signal are of great value for detection of neutrino signal from gravitational collapses in our Galaxy. Such detectors are those that contain scintillator+Fe, for example, LSD (Mont Blanc) and LVD (Gran Sasso). The rremnant of SN 1987A is a natural laboretory for studying the origin of cosmic rays. Close collaboration between supernova and cosmic ray people is extremely welcome.

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