V.M.Chechetkin, I.V.Baykov, A.A.Baranov Keldysh IPM RAS Mechanism of explosion Type-I and Type-II Supernovae

Supernova 87A

SUPERNOVAE Baade (gravitation energyof SN : neurtron star + envelope of SN) Fowler (Nobel Prize),Hoyle (1-thermal instability; 2 - collapse) 1966-Colgate, White (numerical model: collapse neutrino emission throw out the envelope neurtron star ) Arnett (numerical model of detonation supernova) 1970-Imshennik, Nadezin(neutrino diffusion- t about 10 sec.) 1974-Chechetkin,Imshennik,Ivanova(deflagration model of SN, in 1997 model of nucleosynthesis formation of elementsin Fe-peak and formation of heavy elementsin Chechetkin,Ptisin 1980-е)

Supernovae (continuation) Chechetkin, Gershtein, Imshennik, Khlopov(neutrino ignition in SN model* 1981-Chechetkin, Ivanova (Fe-core with 1 М, energy of SN is equal erg)* Cooperstein, Baron (Fe-core with 1.1 М, energy of SN is equal erg, for massive stars the explosion of SN is absent, model «prompt shock») Chechetkin, Popov (the explosionof therotatihg СО- core throw out of envelope along rotating axis - jets) 1989-Colgate и Wilson,Mayle(model «delay shock» -energy of SN erg) Chechetkin (large-scale instability in SN II expplosion) Chandrasekhar,Lebovitz,Ap.J.p – Chechetkin, Popov, Ustuygov (large-scale instability in SN I expplosion), Astr. Rep., 2004, vol. 10, p.1-14.

Simulation of Neutrino Transport by Large-Scale Convective Instability in a Proto-Neutron Star (Suslin, Ustyugov, Chechetkin, Churkina, 2000, Ast.Rep., V 45, March 2001)

In work (Baikov I. V. and Chechetkin V. M., Astron.Rep., 2004, in press) has been kinetic energy of outflow envelope of supernova II type in the depend of mean neutrino energy which must emit from protoneutron star. This energy increase when mean neutrino energy increase too. For example then neutrino energy at 2 time (from 30 MeV to 60 MeV) then kinetic energy of envelope increase on the 20%. Then mean neutrino energy is near 5 MeV the effect outflow is small.

Из проведенных ранее расчетов видно, что вещество с повышенной энтропией поднимается в виде крупномасштабного пузыря к краю протонейтроной звезды. Время формирования конвективной крупномасштабной структуры составляет около 4-5 мс. Средняя скорость пузыря составляет около см/c. Длина свободного пробега нейтрино можно оценить как: Для плотности ~ г/см 3 длина свободного пробега нейтрино с энергиями 50 МэВ и 30 Мэв составляет соответственно l = cm и cm. Такую плотность имеет вещество на расстоянии R ~ 10 6 см от центра звезды, и соответственно пузырь поднимется на такую высоту за время порядка 3 5 мсек.

Радиальная скорость, R 0 =2 10 7, время - около 10 мсек

Кинетическая энергия вещества оболочки со скоростью выше параболической

Estimates of neutrino radiation After 3.5 ms 0.02 М of this material approaches the boundary of the neutrino-sphere, where the density is ρ = g/cm 3, and becomes transparent to the neutrinos there. The density of these neutrinos is comparable to the density of electrons with mean energy 60 MeV. In this case, the intensity of the neutrino emission can be estimated as L = (0.04 М x 60 MeV)/(μ m n x ) ~ erg/s, where μ is the mean molecular mass per electron in the absence of electron- positron pairs. We will now estimate the fraction of energy absorbed by matter per gram in the shock wave from this neutrino radiation. By definition, this is where R is the radius of the shock, is cross-section of weak interaction, where g = ± erg cm 3 - constant Fermi of weak interaction, n 1 = , T 9 3 cm -3 is the density of e ± in the shock wave when T corresponds an ultrarelativistic gas with ρ10 5 T 9 3 g/cm 3. For T 9 = 100, ρ = 10 8 g/cm 3, and R = 10 7 cm, we obtain dε/dt = erg g -1 s -1. This is much more than the neutrino losses from the shock front: dε υ /dt T erg g -1 s -1 ; i.e., the large-scale convection could support a diverging shock wave, leading to the ejection of the supernova envelope.

SN 1987A( 1999 year)