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Sergei I. Blinnikov

Publications and source records attributed to Sergei I. Blinnikov.

39 records · Page 3Linked to original sources

Notes on Hidden Mirror World

A few remarks on Dark Matter (DM) models are presented. An example is Mirror Matter which is the oldest but still viable DM candidate, perhaps not in the purest form. It can serve as a test-bench for other analogous DM models, since the properties of macroscopic objects are quite firmly fixed for Mirror Matter. A pedagogical derivation of virial theorem is given and it is pointed out that concepts of virial velocity or virial temperature are misleading for some cases. It is shown that the limits on self-interaction cross-sections derived from observations of colliding clusters of galaxies are not real limits for individual particles if they form macroscopic bodies. The effect of the heating of interstellar medium by Mirror Matter compact stars is very weak but may be observable. The effect of neutron star heating by accretion of M-baryons may be negligible. Problems of MACHOs as Mirror Matter stars are touched upon.

astro-ph.CO↗

The type IIn supernova 1994W: evidence for the explosive ejection of a circumstellar envelope

We present and analyse spectra of the Type IIn supernova 1994W obtained between 18 and 203 days after explosion. During the luminous phase (first 100 d) the line profiles are composed of three major components: (i) narrow P-Cygni lines with the absorption minima at -700 km/s; (ii) broad emission lines with BVZI ~4000 km/s; and (iii) broad, smooth wings, most apparent in H-alpha. These components are identified with an expanding circumstellar (CS) envelope, shocked cool gas in the forward post-shock region, and multiple Thomson scattering in the CS envelope, respectively. The absence of broad P-Cygni lines from the supernova is the result of the formation of an optically thick, cool, dense shell at the interface of the ejecta and the CS envelope. We model the supernova deceleration and Thomson scattering wings to recover the density, radial extent and Thomson optical depth of the CS envelope during the first month. We reproduce the light curve with a hydrodynamical model and find it to be powered by a combination of internal energy leakage after the explosion of an extended pre-supernova (~10^15 cm) and luminosity from circumstellar interaction. We recover the pre-explosion kinematics of the CS envelope: it is close to homologous expansion with outer velocity ~1100 km/s and a kinematic age of ~1.5 yr. The CS envelope's high mass and kinetic energy, combined with its small age, strongly suggest that the CS envelope was explosively ejected about 1.5 yr before the supernova explosion.

astro-ph↗

SN 1994W: evidence of explosive mass ejection a few years before explosion

We present and analyse spectra of the Type IIn supernova 1994W obtained between 18 and 202 days after explosion. During the first 100 days the line profiles are composed of three major components: (i) narrow P Cygni lines with absorption minima at -700 km/s; (ii) broad emission lines with BVZI ~4000 km/s; (iii) broad wings most apparent in H-alpha. These components are identified with the expanding circumstellar (CS) envelope (Sollerman, Cumming & Lundqvist 1998), shocked cool gas in the forward postshock region, and multiple Thomson scattering in the CS envelope, respectively. The absence of broad P Cygni lines from the supernova (SN) is the result of the formation of an optically thick, cool, dense shell at the interface of the ejecta and the CS envelope. Models of the SN deceleration and Thomson scattering wings are used to recover the Thomson optical depth of the CS envelope and its radial extent, 4E15 cm. The light curve, which we reproduce by a hydrodynamical model, is powered by a combination of internal energy leakage after the explosion of an extended presupernova (~1E15 cm) and luminosity from circumstellar interaction. We recover the pre-explosion kinematics of the CS envelope and find it to be close to homologous expansion with outmost velocity ~1100 km/s and a kinematic age of \~1.5 yr. The high mass and kinetic energy of the CS envelope strongly suggest that the CS envelope was explosively ejected only a few years before explosion.

astro-ph↗