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- ID:
- ivo://CDS.VizieR/J/A+AS/140/327
- Title:
- Fundamental plane galaxies redshifts
- Short Name:
- J/A+AS/140/327
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Radial velocities and central velocity dispersions are derived for 238 E/S0 galaxies from medium-resolution spectroscopy. New spectroscopic data have been obtained as part of a study of the Fundamental Plane distances and peculiar motions of early-type galaxies in three selected directions of the South Equatorial Strip, undertaken in order to investigate the reality of large-scale streaming motion; results of this study have been reported in Mueller et al. (1998ApJ...507L.105M). The new APM South Equatorial Strip Catalog (-17.5deg<{delta}<+2.5deg) (Raychaudhury & Lynden-Bell, 2000) was used to select the sample of field galaxies in three directions: (1) 15h10-16h10; (2) 20h30-21h50; (3) 00h10-01h30. The spectra obtained have a median S/N per {AA} of 23, an instrumental resolution (FWHM) of ~4{AA}, and the spectrograph resolution (dispersion) is ~100km/s. The Fourier cross-correlation method was used to derive the radial velocities and velocity dispersions. The velocity dispersions have been corrected for the size of the aperture and for the galaxy effective radius. Comparisons of the derived radial velocities with data from the literature show that our values are accurate to 40km/s. A comparison with results from Jorgensen et al. (1995MNRAS.276.1341J) shows that the derived central velocity dispersion have an rms scatter of 0.036 in log{sigma}. There is no offset relative to the velocity dispersions of Davies et al. (1987ApJS...64..581D).
- ID:
- ivo://CDS.VizieR/J/A+A/309/749
- Title:
- Fundamental plane of early type galaxies
- Short Name:
- J/A+A/309/749
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyse the residuals to the fundamental plane (FP) of elliptical galaxies as a function of stellar-population indicators; these are based on the line-strength parameter Mg2 and on UBVRI broad-band colors, and are partly derived from new observations. The effect of the stellar populations accounts for approximately half the observed variation of the mass-to-light ratio responsible for the FP tilt. The residual tilt can be explained by the contribution of two additional effects: the dependence of the rotational support, and possibly that of the spatial structure, on the luminosity. We conclude to a constancy of the dynamical-to-stellar mass ratio. This probably extends to globular clusters as well, but the dominant factor would be here the luminosity dependence of the structure rather than that of the stellar population. This result also implies a constancy of the fraction of dark matter over all the scalelength covered by stellar systems. Our compilation of internal stellar kinematics of galaxies is appended.
- 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/ApJ/859/2
- Title:
- Fundamental stellar & halo data for local galaxies
- Short Name:
- J/ApJ/859/2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We build templates of rotation curves as a function of the I-band luminosity via the mass modeling (by the sum of a thin exponential disk and a cored halo profile) of suitably normalized, stacked data from wide samples of local spiral galaxies. We then exploit such templates to determine fundamental stellar and halo properties for a sample of about 550 local disk-dominated galaxies with high-quality measurements of the optical radius R_opt_ and of the corresponding rotation velocity V_opt_. Specifically, we determine the stellar M_*_ and halo M_H_ masses, the halo size R_H_ and velocity scale V_H_, and the specific angular momenta of the stellar j_*_ and dark matter j_H_ components. We derive global scaling relationships involving such stellar and halo properties both for the individual galaxies in our sample and for their mean within bins; the latter are found to be in pleasing agreement with previous determinations by independent methods (e.g., abundance matching techniques, weak-lensing observations, and individual rotation curve modeling). Remarkably, the size of our sample and the robustness of our statistical approach allow us to attain an unprecedented level of precision over an extended range of mass and velocity scales, with 1{sigma} dispersion around the mean relationships of less than 0.1dex. We thus set new standard local relationships that must be reproduced by detailed physical models, which offer a basis for improving the subgrid recipes in numerical simulations, that provide a benchmark to gauge independent observations and check for systematics, and that constitute a basic step toward the future exploitation of the spiral galaxy population as a cosmological probe.
- ID:
- ivo://CDS.VizieR/J/MNRAS/446/2030
- Title:
- FUV and NUV magnitudes of ETG
- Short Name:
- J/MNRAS/446/2030
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We extend our initial study of the connection between the UV colour of galaxies and both the inferred stellar mass-to-light ratio, {Upsilon}*, and a mass-to-light ratio referenced to Salpeter initial mass function (IMF) models of the same age and metallicity, {Upsilon}*/{Upsilon}_Sal_, using new UV magnitude measurements for a much larger sample of early-type galaxies, ETGs, with dynamically determined mass-to-light ratios. We confirm the principal empirical finding of our first study, a strong correlation between the GALEX FUV-NUV colour and {Upsilon}*. We show that this finding is not the result of spectral distortions limited to a single passband (e.g. metallicity-dependent line-blanketing in the NUV band), or of the analysis methodology used to measure {Upsilon}*, or of the inclusion or exclusion of the correction for stellar population effects as accounted for using {Upsilon}*/{Upsilon}_Sal_. The sense of the correlation is that galaxies with larger {Upsilon}*, or larger {Upsilon}*/{Upsilon}_Sal_, are bluer in the UV. We conjecture that differences in the low-mass end of the stellar IMF are related to the nature of the extreme horizontal branch stars generally responsible for the UV flux in ETGs. If so, then UV colour can be used to identify ETGs with particular IMF properties and to estimate {Upsilon}*. We also demonstrate that UV colour can be used to decrease the scatter about the Fundamental Plane and Manifold, and to select peculiar galaxies for follow-up with which to further explore the cause of variations in {Upsilon}* and UV colour.
- ID:
- ivo://CDS.VizieR/J/MNRAS/414/3410
- Title:
- FUV excess in early-type galaxies
- Short Name:
- J/MNRAS/414/3410
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present surface photometry of a sample of 52 galaxies from the GALaxy Evolution eXplorer (GALEX) and Two-Micron All-Sky Survey (2MASS) data archives. These include 32 normal elliptical galaxies, 10 ellipticals with weak LINER or other nuclear activity and 10 star-forming ellipticals or early-type spirals. We examine the spatial distribution of the far-ultraviolet excess in these galaxies, and its correlation with dynamical and stellar population properties of the galaxies.
- ID:
- ivo://CDS.VizieR/J/AJ/140/1194
- Title:
- FUV/HI relations in nearby galaxies
- Short Name:
- J/AJ/140/1194
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We combine data from The HI Nearby Galaxy Survey and the GALEX Nearby Galaxy Survey to study the relationship between atomic hydrogen (HI) and far-ultraviolet (FUV) emission outside the optical radius (r25) in 17 spiral and 5 dwarf galaxies. In this regime, HI is likely to represent most of the interstellar medium (ISM) and FUV emission to trace recent star formation with little bias due to extinction, so that the two quantities closely trace the underlying relationship between gas and star formation rate (SFR).
- ID:
- ivo://CDS.VizieR/J/ApJ/504/113
- Title:
- F175W and F275W photometry of M31 and M32
- Short Name:
- J/ApJ/504/113
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Faint Object Camera (FOC) ultraviolet images of the central 14"x14" of Messier 31 and Messier 32. The hot stellar populations detected in the composite UV spectra of these nearby galaxies are partially resolved into individual stars, and their individual colors and apparent magnitudes are measured. We detect 433 stars in M31 and 138 stars in M32, down to detection limits m_F275W_=25.5mag and m_F175W_=24.5mag.
- ID:
- ivo://CDS.VizieR/J/other/ApSS/365.89
- Title:
- Gaia Alerts with LAMOST and SDSS
- Short Name:
- J/other/ApSS/365
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ESA-Gaia satellite is regularly producing Alerts on objects where photometric variability has been detected after several passages over the same region of the sky. The physical nature of these objects has often to be determined with the help of complementary observations from ground-based facilities. We have compared the list of Gaia Alerts (from the beginning in 2014 to Nov. 1st, 2018) with archival LAMOST and SDSS spectroscopic data. A search radius of 3" has been adopted. In using survey data, the date of the ground-based observation rarely corresponds to the date of the Alert, but this allows at least the identification of the source if it is persistent, or the host galaxy if the object was only transient like a supernova (SN). Some of the objects have several LAMOST observations, and we complemented this search by adding also SDSS DR15 data in order to look for long-term variability. A list of Gaia Nuclear Transients (GNT) from Kostrzewa-Rutkowska et al. (2018. 2018MNRAS.481..307K, Cat. J/MNRAS/481/307), has been included in this search also. We found 26 Gaia Alerts with spectra in LAMOST+SDSS labelled as stars, among which 12 have multi-epoch spectra. A majority of them are Cataclysmic Variables (CVs). Similarly, 206 Gaia Alerts have associated spectra labelled as galaxies, among which 49 have multi-epoch spectra. Those spectra were generally obtained on a date widely different from the Alert date, and are mostly emission-line galaxies with no particularity (except a few Seyferts), leading to the suspicion that most of the Alerts were due to a SN. As for the GNT list, we found 55 associated spectra labelled as galaxies, among them 13 with multi-epoch spectra. In these two galaxy samples, in only two cases, Gaia17aal and GNTJ170213+2543, was the date of the spectroscopic observation close enough to the Alert date: we find a trace of the SN itself in their LAMOST spectrum, both being now classified here as a type Ia SN. Compared to the galaxy sample from the Gaia alerts, the GNT sample has a higher proportion of AGNs, suggesting that some of the detected variations are also due to the AGN itself. Similarly for Quasars, we found only 30 Gaia Alerts but 68 GNT cases associated with single epoch quasar spectra in the databases. In addition to those, 12 plus 23 are quasars where multi-epoch spectra are available. For ten out of these 35, their multi-epoch spectra show appearance or disappearance of the broad Balmer lines and also variations in the continuum, qualifying them as "Changing Look Quasars" and therefore significantly increasing the available sample of such objects.
