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- ID:
- ivo://CDS.VizieR/J/ApJ/689/913
- Title:
- Fundamental planes of early-type galaxies
- Short Name:
- J/ApJ/689/913
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We derive the fundamental plane (FP) relation for a sample of 1430 early-type galaxies (ETGs) in the optical (r band) and the near-infrared (K band), by combining SDSS-DR5 and UKIDSS (UKIRT Infrared Deep Sky Survey, 2007MNRAS.379.1599L), second release data. With such a large, homogeneous data set, we are able to assess the dependence of the FP on the wave band. Our analysis indicates that the FP of luminous early-type galaxies is essentially wave band-independent, with its coefficients increasing at most by 8% from the optical to the NIR. This finding fits well into a consistent picture in which the tilt of the FP is not driven by stellar populations but results from other effects, such as nonhomology. In this framework, the optical and NIR FPs require more massive galaxies to be slightly more metal-rich than less massive ones, and to have highly synchronized ages, with an age variation per decade in mass smaller than a few percent.
- ID:
- ivo://CDS.VizieR/J/A+AS/120/489
- Title:
- Galaxies morphology and IR photometry I.
- Short Name:
- J/A+AS/120/489
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Near Infrared (H-band) surface photometry of 158 (mostly) disk galaxies belonging to the Coma Supercluster and to the A262 and Cancer clusters was obtained using the 256^2^ NICMOS3 array MAGIC attached to the 2.2m Calar Alto telescope. Magnitudes and diameters within the 21.5mag/arcsec^2^ isophote, concentration indices and total H magnitudes are derived.
- ID:
- ivo://CDS.VizieR/J/A+AS/120/521
- Title:
- Galaxies morphology and IR photometry II.
- Short Name:
- J/A+AS/120/521
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present near-infrared H-band (1.65{mu}m) surface photometry of 297 galaxies (mostly) in the Coma Supercluster obtained with the Arcetri NICMOS3 camera, ARNICA, mounted on the Gornergrat Infrared Telescope. Magnitudes and diameters within the 21.5mag/arcsec^2^ isophote, concentration indices, and total H magnitudes are derived. Combining these observations with those obtained similarly using the Calar Alto telescopes (Paper I, <J/A+AS/120/489>) we find a strong positive correlation between the near-infrared concentration index and the galaxy H-band luminosity, and we analyze the consequent dependence of near-infrared growth-curves on H-band luminosity. For a description of the H band photometric system, see e.g. <GCPD/59>
- ID:
- ivo://CDS.VizieR/J/A+AS/142/65
- Title:
- Galaxies morphology and IR photometry III.
- Short Name:
- J/A+AS/142/65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present near-infrared H-band (1.65{mu}m) surface photometry of 558 galaxies in the Coma Supercluster and in the Virgo cluster. This data set, obtained with the Arcetri NICMOS3 camera ARNICA mounted on the Gornergrat Infrared Telescope, is aimed at complementing, with observations of mostly early-type objects, our NIR survey of spiral galaxies in these regions, presented in previous papers of this series. Magnitudes at the optical radius, total magnitudes, isophotal radii and light concentration indices are derived. We confirm the existence of a positive correlation between the near-infrared concentration index and the galaxy H-band luminosity
- ID:
- ivo://CDS.VizieR/J/A+AS/142/73
- Title:
- Galaxies morphology and IR photometry IV.
- Short Name:
- J/A+AS/142/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present near-infrared (H band) surface photometry of 170 galaxies, obtained in 1997 using the Calar Alto 2.2 m telescope equipped with the NICMOS3 camera MAGIC. The majority of our targets are selected among bright members of the Virgo cluster, however galaxies in the A262 and Cancer clusters and in the Coma/A1367 supercluster are also included. This data set is aimed at complementing the NIR survey in the Virgo cluster discussed in Boselli et al. (1997A&A...324L..13B) and in the Coma Supercluster, presented in Papers I, II and III of this series. Magnitudes at the optical radius, total magnitudes, isophotal radii and light concentration indices are derived.
- ID:
- ivo://CDS.VizieR/J/MNRAS/332/422
- Title:
- Galaxies morphology and IR photometry. VIII
- Short Name:
- J/MNRAS/332/422
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the distribution of a statistical sample of nearby galaxies in the {kappa}-space ({kappa1}{prop.to}logM, {kappa}2{prop.to}log(Ie)^3^*M/L, {kappa}3{prop.to}M/L). Our study is based on near-IR (H-band: {lamdba}=1.65{mu}m) observations, for the first time comprising early- and late-type systems. Our data confirm that the mean effective dynamical mass-to-light ratio M/L of the E+S0+S0a galaxies increases with increasing effective dynamical mass M, as expected from the existence of the Fundamental Plane relation. Conversely, spiral and Im/BCD galaxies show broad distribution in M/L with no detected trend of M/L with M, the former galaxies having M/L values about twice larger than the latter, on average. For all the late-type galaxies, the M/L increases with decreasing effective surface intensity Ie, consistent with the existence of the Tully-Fisher relation.
- ID:
- ivo://CDS.VizieR/J/ApJ/744/44
- Title:
- H{alpha} and UV fluxes in nearby galaxies
- Short Name:
- J/ApJ/744/44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We consider the effects of non-constant star formation histories (SFHs) on H{alpha} and GALEX far-ultraviolet (FUV) star formation rate (SFR) indicators. Under the assumption of a fully populated Chabrier initial mass function (IMF), we compare the distribution of H{alpha}-to-FUV flux ratios from ~1500 simple, periodic model SFHs with observations of 185 galaxies from the Spitzer Local Volume Legacy survey. We find a set of SFH models that are well matched to the data, such that more massive galaxies are best characterized by nearly constant SFHs, while low-mass systems experience burst amplitudes of ~30 (i.e., an increase in the SFR by a factor of 30 over the SFR during the inter-burst period), burst durations of tens of Myr, and periods of ~250 Myr; these SFHs are broadly consistent with the increased stochastic star formation expected in systems with lower SFRs. We analyze the predicted temporal evolution of galaxy stellar mass, R-band surface brightness, H{alpha}-derived SFR, and blue luminosity, and find that they provide a reasonable match to observed flux distributions. We find that our model SFHs are generally able to reproduce both the observed systematic decline and increased scatter in H{alpha}-to-FUV ratios toward low-mass systems, without invoking other physical mechanisms.
- ID:
- ivo://CDS.VizieR/J/A+A/396/449
- Title:
- H{alpha} surface photometry in Virgo
- Short Name:
- J/A+A/396/449
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- H{alpha}+[NII] imaging observations of 369 late-type (spiral) galaxies in the Virgo cluster and in the Coma/A1367 supercluster are analyzed, covering 3 rich nearby clusters (A1367, Coma and Virgo) and nearly isolated galaxies in the Great-Wall. They constitute an optically selected sample (mp<16.0) observed with ~60% completeness. These observations provide us with the current (T<10^7^yrs) star formation properties of galaxies that we study as a function of the clustercentric projected distances (Theta). The expected decrease of the star formation rate (SFR), as traced by the H{alpha} equivalent width, with decreasing Theta is found only when galaxies brighter than Mp~19.5 are considered. Fainter objects show no or reverse trends. We also include in our analysis Near Infrared data, providing information on the old (T>10^9^yrs) stars. Put together, the young and the old stellar indicators give the ratio of currently formed stars over the stars formed in the past, or "birthrate" parameter b. For the considered galaxies we also determine the "global gas content" combining HI with CO observations. We define the "gas deficiency'' parameter as the logarithmic difference between the gas content of isolated galaxies of a given Hubble type and the measured gas content.
- ID:
- ivo://CDS.VizieR/J/A+A/428/837
- Title:
- HII regions in minor mergers of galaxies
- Short Name:
- J/A+A/428/837
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of the B, V and I photometry of eleven southern minor mergers. The total apparent B magnitude, integrated B-V and V-I colours were measured. We built B, V, and I equivalent profiles for each galaxy and decomposed them into bulge and disk components when possible. From H{alpha}+N[II] images we have estimated the basic photometric parameters of the HII regions, such as position, size, B-V and V-I colours, H{alpha}+[NII] luminosity and EW(H{alpha}+[NII]) equivalent width.
