We discuss the selection and observations of a large sample of nearby galaxies, which we are using to quantify the star formation activity in the local Universe. The sample consists of 334 galaxies across all Hubble types from S0/a to Im and with recession velocities of between 0 and 3000km/s. The basic data for each galaxy are narrow band H{alpha}+[NII] and R-band imaging, from which we derive star formation rates, H{alpha}+[NII] equivalent widths and surface brightnesses, and R-band total magnitudes. A strong correlation is found between total star formation rate and Hubble type, with the strongest star formation in isolated galaxies occurring in Sc and Sbc types. More surprisingly, no significant trend is found between H{alpha}+[NII] equivalent width and galaxy R-band luminosity. More detailed analyses of the data set presented here will be described in subsequent papers.
We present CCD imaging and photometry in B and Cousins R of the dwarf irregular galaxies UGC 4459 (=DDO 53), UGC 5272 (A=DDO 64 and B), UGC 5340 (=DDO 68), UGC 6456, UGC 7559 (=DDO 126), UGC 8024 (=NGC 4789A=DDO 154), UGC 8091 (= GR 8=DDO 155), UGC 8320 (=DDO 168), UGC 8760 (=DDO 183), and DDO 210. For DDO 210 we also give results in the V filter. Photometry of the resolved stars was carried out on background-subtracted images using DAOPHOT. The tables of measurements include positions, magnitudes, colors, a magnitude error, and a color error. Integrated fluxes and colors are also reported. The single-star photometry is compared to previous results in three of the galaxies (UGC 8024, UGC 8091, DDO 210).
The M33 galaxy is a nearby, relatively metal-poor, late-type spiral. Its proximity and almost face-on inclination means that it projects over a large area on the sky, making it an ideal candidate for wide-field CCD mosaic imaging. Photometry was obtained for more than 106 stars covering a 74'x56' field centered on M33. Main-sequence, supergiant branch, red giant branch, and asymptotic giant branch (AGB) populations are identified and classified based on broadband V and I photometry. Narrowband filters are used to measure spectral features allowing, the AGB population to be further divided into C and M star types. The galactic structure of M33 is examined using star counts, color-color, and color-magnitude-selected stellar populations. We use the C to M star ratio to investigate the metallicity gradient in the disk of M33.
We present a photometric study of the globular clusters (GCs) in the giant elliptical galaxy M60 in the Virgo Cluster, based on deep, relatively wide field Washington CT_1_ CCD images. The CMD reveals a significant population of GCs in M60 and a large number of young luminous clusters in NGC 4647, a small companion spiral northwest of M60. The color distribution of the GCs in M60 is clearly bimodal, with a blue peak at (C-T_1_)=1.37 and a red peak at (C-T_1_)=1.87. We derive two new transformation relations between the (C-T_1_)_0_ color and [Fe/H] using the data for the GCs in our Galaxy and M49. Using these relations, we derive the metallicity distribution of the GCs in M60, which is also bimodal: a dominant metal-poor component with center at [Fe/H]=-1.2, and a weaker metal-rich component with center at [Fe/H]=-0.2. We estimate the total number of the GCs in M60 to be 3600+/-500 and the specific frequency to be S_N_=3.8+/-0.4.
We present the results of a study of streaming motion of galaxy clusters around the Giant Void (RA~13h, DE~40{deg}, z~0.11 and a diameter of 150/hMpc) in the distribution of rich Abell clusters. We used the Kormendy relation as a distance indicator taking into account galaxy luminosities. Observations were carried out in Kron-Cousins R_c_ system on the 6m and 1m telescopes of SAO RAS. For 17 clusters in a spherical shell of 25/hMpc in thickness centered on the void no significant diverging motion (expected to be generated by the mass deficit in the void) has been detected. This implies that cosmological models with low {Omega}_m_ are preferred. To explain small mass underdensity inside the Giant Void, a mechanism of void formation with strong biasing is required.
R-band surface photometry is presented for 171 late-type dwarf and irregular galaxies. For a subsample of 46 galaxies B-band photometry is presented as well. We present surface brightness profiles as well as isophotal and photometric parameters including magnitudes, diameters and central surface brightnesses. Absolute photometry is accurate to 0.1 mag or better for 77% of the sample. For over 85% of the galaxies the radial surface brightness profiles are consistent with published data within the measured photometric uncertainty. For most of the galaxies in the sample HI data have been obtained with the Westerbork Synthesis Radio Telescope. The galaxies in our sample are part of the WHISP project (Westerbork HI Survey of Spiral and Irregular Galaxies), which aims at mapping about 500 nearby spiral and irregular galaxies in HI. The availability of HI data makes this data set useful for a wide range of studies of the structure, dark matter content and kinematics of late-type dwarf galaxies.
As a part of a CCD survey of galaxies belonging or projected onto the Coma and Hercules Superclusters and to the A262, Virgo and Cancer clusters, we present isophote maps and photometric profiles of 87 galaxies (85 taken with the V, 25 with the B and 3 with the U Johnson filters). For the objects in common we compare our results with those in the RC3.
Continuing a CCD survey of galaxies belonging or projected onto the Coma and Hercules Superclusters, to the A262 and Cancer clusters, we present isophote maps and photometric profiles in the Johnson system of 111 galaxies (67 in the V and B bands, 42 only in V, 2 only in B) obtained with the 2.1m telescope at San Pedro Martir (Baja California, Mexico).
