- ID:
- ivo://CDS.VizieR/J/A+AS/142/425
- Title:
- BVRI photometry of 6 galaxies
- Short Name:
- J/A+AS/142/425
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present photometry of the brightest stars in six nearby spiral and irregular galaxies with corrected radial velocities from 340 to 460km/s. Three of them are resolved into stars for the first time. Based on luminosity of the brightest blue stars we estimate the following distances to the galaxies: 5.0Mpc for NGC 784, 9.2Mpc for NGC 2683, 8.9Mpc for NGC 2903, 4.1Mpc for NGC 5204, 6.8Mpc for NGC 5474, and 8.7Mpc for NGC 5585.
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- ID:
- ivo://CDS.VizieR/J/A+AS/142/347
- Title:
- BVRI photometry of NGC 6789
- Short Name:
- J/A+AS/142/347
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we present the results of a detailed B, V, R, I, and H{alpha} study of the isolated nearby blue compact dwarf (BCD) galaxy NGC 6789. The observed galaxy has not yet been resolved into stars up to now. On CCD frames obtained with 6m BTA telescope and 2.5m Nordic telescope the galaxy is well resolved. Its colour-magnitude diagram confirms the two component (core-halo) galaxy morphology, which consists of two stellar populations distinct in structure and colour: an inner high surface-brightness young population within 150pc from the center of the galaxy, and a relatively low surface-brightness intermediate-age population extending out to at least 600pc. The distance to the galaxy, estimated from the tip of the red giant branch (TRGB) is 2.1Mpc which places NGC 6789 close to the Local Group. From the mean colour of the RGB, the mean metal abundance of the halo population is estimated as [Fe/H]=~-1dex.
- ID:
- ivo://CDS.VizieR/J/AJ/119/777
- Title:
- BVRI photometry of Sagittarius dwarf irregular galaxy
- Short Name:
- J/AJ/119/777
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep BVRI CCD photometry of the stars in the dwarf irregular galaxy SagDIG, obtained on the photometric night of 1994 October 8 (UT) using the University of Hawaii 2.2 m telescope at Mauna Kea.
- ID:
- ivo://CDS.VizieR/J/ApJ/682/135
- Title:
- CCD photometry of M60
- Short Name:
- J/ApJ/682/135
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 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.
- ID:
- ivo://CDS.VizieR/J/A+AS/71/297
- Title:
- CCD UBV photometry of stars in Sex A
- Short Name:
- J/A+AS/71/297
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- CCD UBV photometry of 2279 stars in Sextans A is presented. Differences with the photometric scales of Sandage and Carlson (1985AJ.....90.1019S) and Hoessel et al. (1983ApJ...274..577H) are discussed; recalibration of the Sandage and Carlson data for Cepheids in Sextans A results in a smaller value for the distance modulus, {mu}=25.6. A similar value for the distance modulus is obtained from the colour-colour diagram. Colour-colour and colour-magnitude diagrams for the whole galaxy and for different parts are presented indicating a general star formation activity all over Sextans A. The contribution of stars brighter than M_pg_=-3 to the total blue light of the galaxy amounts to 25%, a much higher value than what is found for other dwarf irregular galaxies in the Local Group. The integrated birthrate per unit mass of massive stars for the galaxy is found to be much higher than in the Magellanic Clouds, suggesting that the rate in Sextans A was probably smaller in the past. Different slopes for high mass and low mass IMF parts are needed to account for its low surface brightness. The formation of massive stars seems to be favoured for systems of decreasing mass or, given the relation between total mass and metal content, for galaxies of decreasing metallicity.
- ID:
- ivo://CDS.VizieR/J/MNRAS/497/1791
- Title:
- CCD Washington photometry of Antlia cluster
- Short Name:
- J/MNRAS/497/1791
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an extension of our previous research on the early-type galaxy population of the Antlia cluster (d~35Mpc), achieving a total coverage of ~2.6deg^2^ and performing surface photometry for ~300 galaxies, 130 of which are new uncatalogued ones. Such new galaxies mainly fall in the low surface brightness (LSB) regime, but there are also some lenticulars (S0) which support the existence of unique functions that connect bright and dwarf galaxies in the scaling relations. We analyse the projected spatial distribution of galaxies up to a distance of ~800kpc from NGC 3268, the adopted centre, as well as the radial velocity distribution and the correlation between galaxy colour and effective radius with the projected spatial distribution. We also obtain the luminosity function of the early-type galaxies and the distribution of stellar masses using the T1-band magnitudes and adopted mass-luminosity ratios. Additionally, we correlate the central galaxy distribution with an X-ray emission map from the literature. Based on the analysis of the radial velocities and galaxy colour distributions, we find that galaxies redder than the colour-magnitude relation (CMR) have a velocity distribution strongly concentrated towards the values of the dominant galaxies and are homogeneously distributed throughout the cluster. Those bluer than the CMR, in turn, have a much more extended radial velocity distribution and are concentrated towards the centre of the cluster. We also identify 12 candidates to ultra diffuse galaxies (UDG), that seem to be split into two families, and speculate about their origins in the context of the cluster structure.
- ID:
- ivo://CDS.VizieR/J/AJ/131/2478
- Title:
- M31 and M33 UBVRI photometry
- Short Name:
- J/AJ/131/2478
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present UBVRI photometry obtained from Mosaic images of M31 and M33 using the Kitt Peak National Observatory 4m telescope. We describe our data reduction and automated photometry techniques in some detail, as we will shortly perform a similar analysis of other Local Group galaxies. The present study covered 2.2deg^2^ along the major axis of M31 and 0.8deg^2^ on M33, chosen so as to include all of the regions currently active in forming massive stars. We calibrated our data using photometry from the Lowell 1.1m telescope, and this external method resulted in millimagnitude differences in the photometry of overlapping fields, providing some assurance that our photometry is reliable. The final catalog contains 371781 and 146622 stars in M31 and M33, respectively, where every star has a counterpart in (at least) the B, V, and R passbands. Our survey goes deep enough to achieve 1%-2% photometry at 21mag (corresponding to stars more massive than 20M_{sun}_) and achieves <10% errors at ~U ~B ~V ~R ~I 23mag.
- ID:
- ivo://CDS.VizieR/J/PAZh/35/403
- Title:
- Optical Variabilities in 3C 120
- Short Name:
- J/PAZh/35/403
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on our UBVRI observations and X-ray data from the RXTE satellite we have investigated the variabilities of the Seyfert Galaxy 3C 120 over the period 1996-2008.
- ID:
- ivo://CDS.VizieR/J/MNRAS/462/L11
- Title:
- Passive spiral galaxy cand. multi-phot.
- Short Name:
- J/MNRAS/462/L11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have identified a population of passive spiral galaxies from photometry and integral field spectroscopy. We selected z<0.035 spiral galaxies that have WISE colours consistent with little mid-infrared emission from warm dust. Matched aperture photometry of 51 spiral galaxies in ultraviolet, optical and mid-infrared show these galaxies have colours consistent with passive galaxies. Six galaxies form a spectroscopic pilot study and were observed using the Wide-Field Spectrograph (WiFeS) to check for signs of nebular emission from star formation. We see no evidence of substantial nebular emission found in previous red spiral samples. These six galaxies possess absorption line spectra with 4000{AA} breaks consistent with an average luminosity-weighted age of 2.3Gyr. Our photometric and IFU spectroscopic observations confirm the existence of a population of local passive spiral galaxies, implying that transformation into early-type morphologies is not required for the quenching of star formation.
- ID:
- ivo://CDS.VizieR/J/A+A/415/63
- Title:
- UBVRI surface brightness of 26 bright galaxies
- Short Name:
- J/A+A/415/63
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The UBVRI images of 26 bright spiral galaxies were decomposed in disks and bulges. Correlations of the resulting structural parameters are investigated, giving clues to the formation history of the bulges. We confirm that the large and bright bulges of early-type spirals are similar to elliptical galaxies. They were probably formed prior to the disks in a monolithic collapse or via early mergers. Late-type spirals have tiny and faint bulges with disk-like profiles. These bulges were probably formed after the disk in secular evolution processes, e.g. from a disk instability. The comparison of the color indices of corresponding spirals and bulges with population synthesis computations support above formation scenarios.