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Abstract. Using the IRAS archives, we searched for farinfrared (FIR) counterparts of Shakhbazian Compact Groups of Galaxies (SCGGs). Reliable IRAS detections are identified at the positions of 24 out of 367 SCGGs; another 10 IRAS sources, located within ∼ 2 arcmin of SCGGs, are possibly associated with the corresponding galaxy groups. Some of these sources are not very reliable. Previous work has shown that the fraction of E and S0 galaxies in a representative sample of SCGGs is 77%, while E and S0 galaxies comprise about 51% of galaxies in Hickson Compact Groups (HCGs). The higher fraction of early Hubble types, combined with their greater distances, explains the low IRAS detection rate of SCGGs (7 − 8%) compared to HCGs (64%). The FIR colors and morphological types of galaxies in the groups suggest that active star formation or Seyfert galaxies may be the main source of the FIR emission in the SCGGs detected by IRAS, perhaps originating as the result of tidal interactions in the dense environments of these groups.

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Abstract. Shakhbazian compact galaxy groups belong to the interesting class of compact groups. Because of their large number (the catalogue contains 377 entries) we are able to study the groups in different stages of evolution. Here we give the results of detailed study of four groups, ShCG 154, ShCG 166, ShCG 328 and ShCG 360. We present the redshifts of individual galaxies in groups, the results of the surface photometry in BVR, the contourplots of the surface brightness versus effective radius of galaxies, the twisting postion angle versus effective radius of galaxies, the radial velocity dispersions, the crossing times, the mass-to-luminosity ratios of groups and the results of the X-ray study. The dynamical state of groups, interactions between member galaxies, and the physical parameters of groups are discussed.

We present the position and references (if available) of all the galaxies of the Shakhbazian survey being the largest survey of compact galaxy groups. For the estimation of the coordinates the Digitized Sky Survey was used. This paper contains the data of 48 Shakhbazian groups north of δ > + 2deg;30' (Shkh 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 22, 23, 25, 26, 28, 29, 31, 34, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56).

The eighth part of the catalogue of Shakhbazian groups contains the positions and references of all the galaxies of the following 48 groups (north of 6 >

The tenth part of the catalogue of Sliakltbazian groups contains the positions and references of all t.he galaxies of t . 1~following 35 groups (north of 6 > $2'30'):

We have completed an investigation (preliminary results for which were reported in Oleak et al. 1995) into the shapes of Shakhbazian compact groups of galaxies. Ellipticities for 299 groups in the Shakhbazian survey have been examined using the technique proposed by Rood (1979) for deriving the average "flatness" of a large sample of objects. The distribution of the apparent axial ratios (g = b / a ) for the groups is found to be broad with a mean of < b/a >-0.5. This distribution is compared with randomly generated spherical and elliptical model systems. The results confirm the findings of our earlier study: the frequency distribution of axial ratios for Shakhbazian groups is represented solely by a population of prolate spheroids with low intrinsic axial ratios, < q >= 0.3, u = ~k0.17 (assuming random true orientations in 3D space). This now provides further strong evidence that the Shakhbazian groups are more highly flattened than either rich clusters or elliptical galaxies, and represent the most elongated systems yet found. The result also provides confirmation of the reality of the groups, since in the case of systems of chance line-of-sight superpositions of galaxies we would expect to see much higher axial ratios.