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تسجيل مستخدم جديدParameters of the type-IIP supernova SN 2012aw
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We present the results the photometric observations of the Type IIP supernova SN 2012aw obtained for the time interval from 7 till 371 days after the explosion. Using the previously published values of the photospheric velocities weve computed the hydrodynamic model which simultaneously reproduced the photometry observations and velocity measurements. The model was calculated with the multi-energy group radiation hydrodynamics code STELLA. We found the parameters of the pre-supernova: radius $R = 500 R_odot$, nickel mass $M(^{56}$Ni$)$ $sim 0.06 M_odot$, pre-supernova mass $25 M_odot$, mass of ejected envelope $23.6 M_odot$, explosion energy $E sim 2 times 10^{51}$ erg. The model progenitor mass $M=25 M_odot$ significantly exceeds the upper limit mass $M=17 M_odot$, obtained from analysis the pre-SNe observations. This result confirms once more that the Red Supergiant Problem must be resolved by stellar evolution and supernova explosion theories in interaction with observations.
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We present optical photometry and spectroscopy from about a week after explosion to $sim$272 d of an atypical Type IIP supernova, SN 2015ba, which exploded in the edge-on galaxy IC 1029. SN 2015ba is a luminous event with an absolute V-band magnitude
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