New Results of Observations of the Only Supernova Remnant in the IC1613 Galaxy

The new results of a study of the kinematics of the supernova remnant S8 in the IC1613 galaxy are reported. The expansion velocity of the bright optical nebula is determined based on observations made with the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences using MPSF field spectrograph and SCORPIO focal reducer operating in the scanning Fabry--Perot interferometer mode. An analysis of 21-cm line VLA observations of the galaxy corroborates our earlier proposed model of a SN exploding inside a cavern surrounded by a dense shell and S8 colliding with the wall of the HI shell.Comment: 8 pages, 7 figures; accepted for publication in Astronomy Letter

A synchrotron superbubble in the IC 10 Galaxy: a hypernova remnant?

The nature of the synchrotron superbubble in the IC 10 galaxy is discussed using the results of our investigation of its ionized gas structure, kinematics, and emission spectrum from observations made with the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences, and based on our analysis of the radio emission of the region. The hypernova explosion is shown to be a more plausible mechanism of the formation of the synchrotron superbubble compared with the earlier proposed model of multiple supernova explosions. A compact remnant of this hypernova may be identified with the well known X-ray binary X-1 -- an accreting black hole.Comment: 4 pages, 3 EPS figures, Accepted to MNRAS (in Letters

Observations of Stellar Objects at a Shell Boundary in the Star-Forming Complex in the Galaxy IC1613

The single region of ongoing star formation in the galaxy IC 1613 has been observed in order to reveal the nature of compact emission-line objects at the edges of two shells in the complex, identified earlier in H-alpha line images. The continuum images show these compact objects to be stars. Detailed spectroscopic observations of these stars and the surrounding nebulae were carried out with an integral field spectrograph MPFS mounted on the 6m telescope of the Special Astrophysical Observatory. The resulting stellar spectra were used to determine the spectral types and luminosity classes of the objects. An Of star we identified is the only object of this spectral type in IC 1613. The results of optical observations of the multi-shell complex are compared to 21cm radio observations. The shells harboring the stars at their boundaries constitute the most active part of the star-forming region. There is evidence that shocks have played an important role in the formation of the shells.Comment: 10 pages, 5 PS and 1 color JPEG figur