Small water-filled cavities, often of basically hexagonal shape, that appear in the interior of ice masses upon which light is falling. Their formation results from the melting ice by radiative absorp
tion at points of defect in the ice crystal lattice.
A Type I supernova that presents a singly-ionized silicon (Si II) absorption feature at 6150 Å near peak brightness. Type Ia SNe are believed to result from mass accretion to a carbon-oxygen white dwa
rf in a close binary system. When the white dwarf mass exceeds the Chandrasekhar limit, the degenerate electron pressure can no longer support the accumulated mass and the star collapses in a thermonuclear explosion producing a supernova. The peak luminosity of SNe Ia is set by the radioactive decay chain, and the observed photometric correlation between the peak luminosity and the time-scale over which the light curve decays from its maximum is understood physically as having both the luminosity and opacity being set by the mass of Nickel-56 synthesized in the explosion. Type Ia supernovae occur in all types of galaxies. Type Ia SNe are used as standard candles in determining cosmological distances, after normalizing their light curves with the Phillips relation.
A Type I supernova that presents a singly-ionized silicon (Si II) absorption feature at 6150 Å near peak brightness. Type Ia SNe are believed to result from mass accretion to a carbon-oxygen white dwa
rf in a close binary system. When the white dwarf mass exceeds the Chandrasekhar limit, the degenerate electron pressure can no longer support the accumulated mass and the star collapses in a thermonuclear explosion producing a supernova. The peak luminosity of SNe Ia is set by the radioactive decay chain, and the observed photometric correlation between the peak luminosity and the time-scale over which the light curve decays from its maximum is understood physically as having both the luminosity and opacity being set by the mass of Nickel-56 synthesized in the explosion. Type Ia supernovae occur in all types of galaxies. Type Ia SNe are used as standard candles in determining cosmological distances, after normalizing their light curves with the Phillips relation.
A Type I supernova that has neutral helium line (He I) at 5876 Å, and no strong silicon (Si II) absorption feature at 6150 Å. Type Ib supernovae are believed to result from the evolution of massive st
ars.
A Type I supernova that has neutral helium line (He I) at 5876 Å, and no strong silicon (Si II) absorption feature at 6150 Å. Type Ib supernovae are believed to result from the evolution of massive st
ars.
A Type I supernova that shows weak or no helium lines and no strong silicon (Si II) absorption feature near 6150 Å. Type Ic supernovae are believed to result from the evolution of massive stars.