Search Publications

HD/H₂ molecular clouds in the early Universe: The problem of primordial deuterium

Balashev, S. A.; Ivanchik, A. V.; Varshalovich, D. A.

We have detected new HD absorption systems at high redshifts, z _abs = 2.626 and z _abs = 1.777, identified in the spectra of the quasars J0812+3208 and Q1331+170, respectively. Each of these systems consists of two subsystems. The HD column densities have been determined: log N {_HD/^A} = 15.70 ± 0.07 for z…

Distance to the galaxy IC 342

Tikhonov, N. A.; Galazutdinova, O. A.

Based on archival Hubble Space Telescope images, we have performed stellar photometry for a region of the spiral galaxy IC 342 located in the Milky Way zone. On the constructed Hertzsprung-Russell diagram, we have identified the red giant branch and determined the distance modulus for the galaxy by the TRGB (tip of the red giant branch) method, ( …

Star formation history in the central region of the barred galaxy NGC 7177

Sil'Chenko, O. K.; Smirnova, A. A.

Using the method of two-dimensional spectroscopy, we have investigated the kinematics and distribution of the gas and stars at the center of the early-type spiral galaxy NGC 7177 with a mediumscale bar as well as the change in the mean age of the stellar population along the radius. A classical picture of radial gas inflow to the galactic center a…