Astron. Astrophys. Suppl. Ser. 139, 141-161

The galaxy cluster Abell426 (Perseus). A catalogue of 660 galaxy positions, isophotal magnitudes and morphological types

J. Brunzendorf - H. Meusinger

Thüringer Landessternwarte Tautenburg, Sternwarte 5, D- 07778 Tautenburg, Germany
e-mail: brunz@tls-tautenburg.de/meus@tls-tautenburg.de

Received March 3; accepted July 1, 1999

Abstract:

We present a homogeneous catalogue of galaxies in the field of the nearby galaxy cluster A426 (Perseus) based on a survey of digitised Schmidt plates taken with the Tautenburg 2m telescope in the B band. Accurate positions, morphological types, B₂₅ isophotal magnitudes, angular radii and position angles are given for 660 galaxies within a field of about 10 square-degrees, centred on $\alpha = 3^{\rm h}\,21^{\rm min},\,\delta = 41\hbox{$^\circ$}\,33'$(J2000). When available, the radial velocity and the most common name taken from NED or PGC are included. The catalogue comprises galaxies brighter than $B_{25}\approx19.5$. The estimated limit of completeness is $B_{25}\approx18$.Two thirds of the galaxies are published for the first time. The galaxy positions are measured with a mean accuracy of $0\hbox{$.\!\!^{\prime\prime}$}5$,the photometric accuracy is of the order of 0.1 to 0.2mag depending on image crowding and galaxy shape. Morphological properties were evaluated from the visual inspections of both deep images obtained from the digital co-addition of a large number of plates and higher-resolution images from single plates taken under good seeing conditions. The superimposed images unveil faint structures down to $\mu_B\approx 27$magarcsec^-2.

The catalogue is applied to a study of statistical properties of the galaxies in A426: projected distribution of morphological types, segregation of morphological types, position of the cluster centre, distribution of galaxy position angles, type-dependent luminosity functions, and total B-luminosity of the the cluster. In agreement with previous studies, we find a relative spiral-deficiency in the central region (). The percentage of identified S+Irr increases, however, increases from 30% in the centre to more than 50% in the outer parts. The projected distributions of early- and late-type galaxies are not co-centred. The total luminosity of all supposed member galaxies in the surveyed area is estimated to $(6.5\pm0.9)\ 10^{12} \times h_{50}^{-2}$ blue solar luminosities. We do not analyse in detail possible substructures in the projected distribution of galaxies. However, we found a pronounced clump of galaxies at $\alpha ({J}2000.0) = 3^{\rm h}20\hbox{$.\!\!^{\rm m}$}4$, $\delta ({J}2000.0) = 43\hbox{$^\circ$}4'$,which is shown to be a background cluster at $z\approx 0.050$.

Key words: galaxies: clusters: individual: A426 -- galaxies: fundamental parameters -- galaxies: luminosity function