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We examine the precision of the Tully-Fisher relation (TFR) using a sample of galaxies in the Coma region of the sky, and find that it is good to 5% or better in measuring relative distances. Total magnitudes and disk axis ratios are derived from H and I band surface photometry, and Arecibo 21 cm profiles define the rotation speeds of the galaxies. Using 25 galaxies for which the disk inclination and 21 cm width are well defined, we find an rms deviation of 0.10 mag from a linear TFR with dI/d(log W(sub c)) = -5.6. Each galaxy is assumed to be at a distance proportional to its redshift, and an extinction correction of 1.4(1-b/a) mag is applied to the total I magnitude. The measured scatter is less than 0.15 mag using milder extinction laws from the literature. The I band TFR scatter is consistent with measurement error, and the 95% CL limits on the intrinsic scatter are 0-0.10 mag. The rms scatter using H band magnitudes is 0.20 mag (N = 17). The low width galaxies have scatter in H significantly in excess of known measurement error, but the higher width half of the galaxies have scatter consistent with measurement error. The H band TFR slope may be as steep as the I band slope. As the first applications of this tight correlation, we note the following: (1) the data for the particular spirals commonly used to define the TFR distance to the Coma cluster are inconsistent with being at a common distance and are in fact in free Hubble expansion, with an upper limit of 300 km/s on the rms peculiar line-of-sight velocity of these gas-rich spirals; and (2) the gravitational potential in the disks of these galaxies has typical ellipticity less than 5%. The published data for three nearby spiral galaxies with Cepheid distance determinations are inconsistent with our Coma TFR, suggesting that these local calibrators are either ill-measured or peculiar relative to the Coma Supercluster spirals, or that the TFR has a varying form in different locales.

We explore the known dependence of the slope of the Tully-Fisher (TF) relation on observational wavelength using a large multifrequency galaxy data-base. We confirm that (1) in the infrared the slope of the TF relation is close to the value expected for constant mass-to-light ratio, while in the visible it increases with mass. Equivalently we show that the infrared luminosity is a good tracer of the dynamical mass in galaxies, whereas the fraction of blue light decreases with increasing mass. (2) B-H increases with mass (H luminosity) for galaxies of a given Hubble type and, at fixed H luminosity, it is larger in early morphological types. (3) The present star-formation rate and the H I content per unit mass both decrease with increasing dynamical mass

We have started a large project to study the NIR Tully-Fisher (TF) relation using H- and I-band surface photometry of spiral galaxies. A preliminary study of 20 spirals in the Coma and Abell 400 clusters is presented. The NIR images have been used to derive accurate inclinations and total magnitudes, and rotational linewidths are measured from high-quality 21-cm Arecibo data. The scatter in the Coma TF plot is found to be 0.19 mag in the H band and 0.20 mag in the I band for a set of 13 galaxies, if we assume that they are all at the same distance. The deviation of the Coma galaxies from the best-fit Tully-Fisher relation is correlated with their redshift, indicating that some of the galaxies are not bound to the cluster. Indeed, if we treat all the galaxies in the Coma sample as undergoing free Hubble expansion, the TF scatter drops to 0.12 and 0.13 mag for the H- and I-band datasets, respectively. The Abell 400 sample is best fit by a common distance model, yielding a scatter of 0.12 mag for seven galaxies in H using a fixed TF slope. We are in the process of studying cluster and field spirals out to about 10,000 km/s in order to calibrate the NIR TF relation and will apply it to more nearby galaxies to measure the peculiar velocity field in the local universe.

A Tully-Fisher analysis is carried out for a complete sample of spiral galaxies in the Virgo Cluster with the use of newly obtained accurate photometry data. We present the evidence that spiral galaxies in the Virgo Cluster are distributed in an elongated region, like a filament, which extends from 13 to 30 Mpc almost along the line of sight (offset 6° toward SSW) with the maximum of the density distribution at around 15 Mpc. This explains the discrepancy in the distance modulus and the dispersion among various authors who carried out Tully-Fisher analyses for the Virgo Cluster

We describe a distance indicator for spiral galaxies using detailed rotation curves derived from Hα velocity fields and I band CCD photometry. Two-dimensional velocity fields are obtained with an imaging Fabry-Perot spectrometer, with a velocity accuracy of better than 10 km/s. Rotation curves, based upon rotating disks geometries, are fit to these velocity fields. We present the I band photometry profiles, and the individual rotation curves for 75 galaxies. The extracted circular velocity is combined with I band magnitudes to form a Tully-Fisher relation, with a scatter of ∼0 m 25-0 m 3 mag

Several aspects of using the Tully-Fisher relation to estimate magnitudes and distances are examined, in particular the effect of the luminosity function on the theoretical estimation of regression parameters, unbiased estimates of absolute magnitude, and the Malmquist bias of field galaxies. With respect to observations of clusters of galaxies, if the limiting absolute magnitude is close to or brighter than the Schecter magnitude M * there is a significant difference in the slopes and offsets of the regression of magnitude upon log (line width) as calculated from Gaussian and Schecter functions

Optical CCD and 21 cm H I data are combined here via the Tully-Fisher relation to study the Galactic extinction in the V an I bands over an angular scale of a few arcmin at absolute Galactic latitudes between 2 and 16 deg. Extinctions in V and I bands are found to be linearly correlated with A(I) about 0.58 A(V), with no noticeable environmental dependence and consistent with existing results of Galactic reddening. There is a large scatter in the simple linear relation with csc /b/, confirming the existence of 'holes' and patches at low Galactic latitudes. The mean correlation between Galactic extinction and H I column density over a comparable angular scale is also found to be consistent with those at high latitudes over large angular scales. Correlation is also found between optical extinction and the IRAS 100 micron sky brightness, and this sky brightness is only slightly worse than H I column density as an indicator for optical extinction.

The velocity field in the Local Supercluster (LS) is studied on the basis of a newly compiled data set of peculiar velocities of 306 spiral galaxies as well as two well-known samples by Aaronson et al. (194 spirals) and by Faber et al. (400 ellipticals). Our sample is the largest one of spiral galaxies available at present with distance estimates as good as those for the sample of Aaronson et al. Galaxy distances in our sample are determined in this study using the Tully-Fisher relation

Photometry is presented for spiral galaxies in five clusters of galaxies in the direction of the Perseus-Pisces supercluster. The 21 cm observations of these galaxies by Giovanelli et al. (1986, AJ, 92) are employed to measure distances of these clusters by means of the Tully-Fisher relation. Most of these are in fact more distant than the supercluster and have peculiar velocities averaging -400 km/s

Relative distances of 16 clusters of galaxies in the redshift range from 3000 to 11,000 km s −1 are measured using the I-band Tully-Fisher relation. Different techniques of deriving distances of clusters using a distance indicator are discussed and compared in regard to the sample selection bias

We review seven of the most reliable indicators used for deriving distances to galaxies as far way as 100 Mpc: globular-cluster luminosity functions (GCLF), novae, Type Ia supernovae (SN Ia), H I-line-width relations, planetary-nebula luminosity functions (PNLF), surface-brightness fluctuations (SBF), and fundamental-plane relationships for elliptical galaxies (Dn - sigma). In addition, we examine the use of Cepheid variables since these serve to set zero points for most of the methods. We pay particular attention to the uncertainties inherent in these methods, both internal and external. We then test these uncertainties by comparing distances derived with each technique to distances derived from surface-brightness fluctuations. We find that there are small systematic offsets between the PNLF, GCLF, and SBF methods, with the PNLF and GCLF distances being on average 6% and 13% larger than those of the SBF method. The dispersion between the PNLF and SBF distances is 8%; the GCLF-SBF dispersion is 16%, the SN Ia-SBF dispersion is 28%, Dn-sigma-SBF dispersion is 26%, and the Tully-Fisher-SBF dispersion is 32%. The latter value drops to 14%, however, when one considers only well-mixed groups, suggesting that the spiral galaxies measured with Tully-Fisher are not always spatially coincident with the groups' elliptical galaxies. In the mean, all the methods agree extremely well. We also present a summary of distances to the Virgo Cluster. Weighted and unweighted averages of the seven methods yield Virgo distances of 16 ± 1.7 and 17.6 ± 2.2 Mpc, respectively. The overlap among all the indicators is well within the expected accuracies of the methods. Using the weighted or unweighted Virgo distances to bootstrap to the Coma Cluster, we find the Hubble constant to be either 80 ± 11 or 73 ± 11 km s-1 Mpc-1 respectively.

An analysis has been made of the Hubble flow for galaxies in the Pisces-Perseus supercluster region using the Tully-Fisher (TF) relation in the B band, applied to the sample of Giovanelli & Haynes (1989, AJ, 97). The number of galaxies, the depth, and the completeness of this sample offer an advantage over previous observations used in determination of the Hubble constant beyond the Virgo Cluster. Photographic surface photometry was carried out on 155 galaxies to correct for the scale error and establish the zero point of the Zwicky magnitudes, which is used in the present analysis

We measure peculiar velocities for a sample of 48 late-type spiral galaxies which are located in the general vicinity of the Great Attractor (GA). Relative distances are derived using the I-band Tully-Fisher relation. We confirm the existence of positive velocity residuals, with amplitude 500-2000 km/s in the Hydra-Centaurus region, for galaxies located at kinematic distances of 20-30 Mpc. Beyond 45 Mpc, we have a very weak signal of negative velocity residuals whose amplitude is very sensitive to the form of the Malmquist correction. However, positive velocity residuals can be detected in galaxies with distances as large as 80 Mpc

The first results of a survey of the peculiar velocities of 1355 spiral galaxies in the southern sky using the Tully-Fisher relation to estimate their distances are presented. The most important result of these measurements is that no back-side infall into the Great Attractor is found, contrary to the findings of Dressler & Faber (1990, ApJ, 354); rather, evidence is found for a bulk flow of about 600 km/s on scales greater than 60 h -1 Mpc

Multicolor CCD photometry is presented for a sample of 15 spiral and irregular members of the Local, Sculptor, and M81 groups with M B ≤ -16.0 and relevant as potential calibrators of the luminosity-line width relations. The sample contains those galaxies for which a ground-based study of Cepheid variables could provide accurate distances and hence an absolute calibration for the relations. Unfortunately, only six of the systems presently have reliable independent distance estimates, but this number is sufficient to provide a reasonable calibration

For a complete (but magnitude-limited) sample of Virgo Cluster spiral galaxies, we present 1.65 μm photometry derived from images. Both galaxy inclinations and H-magnitudes are derived from the new data. The new photometry agrees with previous measurements. The infrared inclinations from the present data are usable for galaxies having inclinations greater than 45°, but deeper images would be needed for galaxies more face-on than this

Distances and peculiar velocities for galaxies in eight clusters and groups have been determined by means of the near-infrared Tully-Fisher relation. With the possible exception of a group halfway between us and the Hercules Cluster, we observe peculiar velocities of the same order as the measuring errors of about 400 km/s. The present sample is drawn from the northern Galactic hemisphere and delineates a quiet region in the Hubble flow. This contrasts with the large-scale flows seen in the Hydra-Centaurus and Perseus-Pisces regions. We compare the observed peculiar velocities with predictions based upon the gravity field inferred from the IRAS redshift survey. The differences between the observed and predicted peculiar motions are generally small, except near dense structures, where the observed motions exceed the predictions by significant amounts. Kinematic models of the velocity field are also compared with the data. We cannot distinguish between parameterized models with a great attractor or models with a bulk flow.

The Tully-Fisher relation is used to derive distances of 262 galaxies in seven clusters. Care is taken to reduce possible causes of error in the distance determination and to evaluate sources of scatter in the distance-velocity relation. The scatter in Virgo, A262 (and possibly in the Coma and Hercules superclusters) is real and is evidence of large-scale (50 Mpc) peculiar velocity fields. In the Virgo region we confirm the existence of background galaxies infalling toward the cluster (see work by Pierce and Tully) and we find evidence for infalling foreground objects. The Cancer cluster is confirmed to be an unbound collection of groups (see work by Bothun et al.)

The present estimate of the distance to the Coma cluster on the basis of the B-band Tully-Fisher (T-F) relation has conducted photographic surface photometry on all galaxies for which H I line width data in a circle of 4-deg radius centered on the Coma cluster. A detailed estimate is made of the cluster population incompleteness bias for the distance estimation. While the correction for sample incompleteness, in conjunction with the T-F relation, increases the distance modulus, the result cannot be as large as the value indicated by Kraan-Kortweg et al. (1988). 65 refs.

A true distance modulus to the nearby spiral galaxy M33 has been determined based on CCD photometry obtained at BVRI wavelengths. M33 is presently one of five nearby galaxies used in the calibration of the IR Tully-Fisher relation, and thereby in the determination of the Hubble constant. Using period-luminosity relations at several wavelengths offers the advantage that the distance moduli derived can be corrected for the effects of interstellar extinction. These data indicate that there is internal reddening affecting the Cepheid photometry in M33 which must be accounted for if a true distance modulus is to be obtained for this galaxy. Adopting a true distance modulus to the LMC of 18.5 mag, the new CCD data yield a true distance to M33 of 24.64 + or - 0.09 mag, corresponding to a linear distance of 840 kpc. A mean value of the total color excess (foreground and internal) for the Cepheids in M33 is estimated to be E(B - V) = 0.10 + or - 0.09 mag, assuming a value for the total mean LMC Cepheid color excess of 0.10 mag.

The Tully-Fisher relation (TFR) in different environments was investigated in 13 galaxy samples spanning a large range in galaxy densities, using two statistical tests to compare the TFR of different samples. Results of the analysis of TFR parameters in several environments showed that, when samples of similar data-accuracy and magnitude-range were compared, there was no significant difference between the galaxy samples. It is suggested that a comparison of samples with very different data accuracy or those biased by incompleteness effects may lead to misleading results. 60 refs.

Un etalonnage de la relation de Tully-Fisher infrarouge est presente sur la base des distances recemment determinees de 5 galaxies. Ces nouvelles distances ont toutes ete determinees par photometrie CCD de Cepheides. La dispersion de la relation est tres faible, s'elevant a seulement ± 0.15 mag.

A review of large-scale investigations of the determination of H is presented. The infrared period-luminosity relation of Cepheids gives distances accurate to -2% to nearby galaxies. Based on the distances of M31, MH, N300 and N2403, a DM of 31 �30 �O� 20 has been derived to the nearby Virgo cluster from the TF relation of spirals at four wavebands. Distances to more distant clusters extending up to a redshift of -10000 km S-I obtained through the CM relation of E galaxies, the TF relation of spirals and the velocity dispersion-luminosity relation of E galaxies give a value of H of 71 km S-I Mpcl when these distances are normalised to a Virgo DM of 31�30. The scatter in the redshift-distance relation of these clusters is -500 km s-I arising from the presence of unaccounted peculiar motions of individual clusters. The magnitude limited all-sky samples of galaxies also give a value of H near 70 km S-I Mpcl once the data are corrected for Malmquist bias. The best value of the global Hubble constant obtained from the redshift-distance data of Virgo and farther clusters, as well as the magnitude limited samples involving various methods of determining distances by different observers, is 73 km S-i Mpcl . Taking into account the error in the calibration of our DM of Virgo we can set a generous error of 10 to this value of H.

The behavior of the B-band Tully-Fisher (TF) relation with respect to the observational biases and parameter uncertainties is studied from an almost complete sample of spiral galaxies belonging to the Virgo Cluster. The strong influence of the limiting apparent magnitude when using the direct TF relation is confirmed. A distance modulus of 31.4 + or - 0.2 is found along with a corresponding H(0) = 68 + or - 8 km/s/Mpc, assuming a cosmological velocity of the cluster V = 1300 + or - 100 km/s. The Virgo S and S-prime clouds are shown to lie at significantly different distances. Different distance moduli found by other authors are explained. 127 refs.

The Tully-Fisher relation applied in the infrared appears to be the best global distance indicator presently available for determining the expansion rate and deviations from uniform Hubble flow. In this article recent results obtained using the IR/H I method are reviewed. A Virgo-directed Local Group velocity of about 300 km s–1 is indicated (implying a local value for the deceleration parameter qo ~ 0.05 – 0.1) along with a “best guess” value for the Hubble Constant of 85 km s-1 Mpc-1.

The degeneracy among the disc, bulge and halo contributions to galaxy rotation curves prevents an understanding of the distribution of baryons and dark matter in disc galaxies. In an attempt to break this degeneracy, we present an analysis of the strong gravitational lens SDSS J2141-0001, discovered as part of the Sloan Lens ACS survey. The lens galaxy is a high-inclination, disc-dominated system. We present new Hubble Space Telescope multicolour imaging, gas and stellar kinematics data derived from long-slit spectroscopy and K-band laser guide star adaptive optics imaging, both from the Keck telescopes. We model the galaxy as a sum of concentric axisymmetric bulge, disc and halo components and infer the contribution of each component, using information from gravitational lensing and gas kinematics. This analysis yields a best-fitting total (disc plus bulge) stellar mass of log10(M*/M⊙) = 10.99+0.11- 0.25. The photometric data combined with stellar population synthesis models yield log10(M*/M⊙) = 10.97 ± 0.07 and 11.21 ± 0.07 for the Chabrier and Salpeter initial mass functions (IMFs), respectively. Assuming no cold gas, a Salpeter IMF is marginally disfavoured, with a Bayes factor of 2.7. Accounting for the expected gas fraction of ≃ 20 per cent reduces the lensing plus kinematics stellar mass by 0.10 ± 0.05 dex, resulting in a Bayes factor of 11.9 in favour of a Chabrier IMF. The dark matter halo is roughly spherical, with minor to major axis ratio q3, h= 0.91+0.15- 0.13. The dark matter halo has a maximum circular velocity of Vmax= 276+17- 18 km s-1, and a central density parameter of log10ΔV/2= 5.9+0.9- 0.5. This is higher than predicted for uncontracted dark matter haloes in Λ cold dark matter cosmologies, log10ΔV/2= 5.2, suggesting that either the halo has contracted in response to galaxy formation, or that the halo has a higher than average concentration. Larger samples of spiral galaxy strong gravitational lenses are needed in order to distinguish between these two possibilities. At 2.2 disc scalelengths the dark matter fraction is fDM= 0.55+0.20- 0.15, suggesting that SDSS J2141-0001 is submaximal. Based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555. These observations are associated with programmes 10587 and 11978.

We investigate the stellar kinematics of the bulge and disk components in 826 galaxies with a wide range of morphology from the Sydney-AAO Multi-object Integral-field spectroscopy (SAMI) Galaxy Survey. The spatially-resolved rotation velocity (V) and velocity dispersion ($\sigma$) of bulge and disk components have been simultaneously estimated using the penalized pixel fitting (pPXF) method with photometrically defined weights for the two components. We introduce a new subroutine of pPXF for dealing with degeneracy in the solutions. We show that the V and $\sigma$ distributions in each galaxy can be reconstructed using the kinematics and weights of the bulge and disk components. The combination of two distinct components provides a consistent description of the major kinematic features of galaxies over a wide range of morphological types. We present Tully-Fisher and Faber-Jackson relations showing that the galaxy stellar mass scales with both V and $\sigma$ for both components of all galaxy types. We find a tight Faber-Jackson relation even for the disk component. We show that the bulge and disk components are kinematically distinct: (1) the two components show scaling relations with similar slopes, but different intercepts; (2) the spin parameter $\lambda_R$ indicates bulges are pressure-dominated systems and disks are supported by rotation; (3) the bulge and disk components have, respectively, low and high values in intrinsic ellipticity. Our findings suggest that the relative contributions of the two components explain, at least to first order, the complex kinematic behaviour of galaxies., Comment: 22 pages, 21 figures; Accepted for publication in MNRAS

The 21-cm line width is a good indication of the maximum rotational velocity in a galaxy. However, the turbulent motions affect the observed line width and must be corrected. Not taking them into account introduces both accidental and systematic errors.A first example of this effect is the dependence of the slope a of the Tully-Fisher relation:on the level at which the line width ΔVobs. is measured. In their 1977 paper, Tully and Fisher find the following values:A second example is the departure from linearity in the H-band Tully-Fisher relation obtained by Aaronson et al. (1982) (their figure 2): the narrow lines are more strongly affected by these turbulent motions.

The influence of the virgocentric model in the study of Malmquist bias in TF relation is investigated from field galaxies and Virgo cluster.

The observed scatter in the H-band Tully-Fisher relation is O.45 — O.5 O mag (Aaronson and Mould 1983, Aaronson et al. 1986). In order to yield more reliable information concerning the local form of the velocity-distance relation, it is desirable to obtain relative distances to galaxies that are accurate to 1O%. The present scatter in the Tully-Fisher relation thus needs to be reduced by a factor of 2. In this contribution, we report on the sources of scatter in the Tully-Fisher relation and elaborate on a possible scheme which yields a scatter of only O.25 mag.

We discuss the possibilities of using the velocity width integrated luminosity relation for spiral galaxies at cosmologically interesting redshifts. Our estimates and discussion show that questions of cosmological nature can be usefully addressed by use of optical lines such as Hα, when observed as integrated profiles on a 16-m ground-based telescope such as ESO’s VLT.

Among existing secondary distance indicators, the IR Tully-Fisher relation is probably the most reliable available for measuring the far flung Hubble flow. Absolute calibration of the method, however, remains highly uncertain owing to the poor state of nearby galaxy distances. A coordinated ground-based and space attack on this problem, primarily involving Cepheids, holds out great promise for a measurement of the Hubble constant good to ten percent.

Numerous attempts have been made to calibrate the Tully-Fisher relation (between absolute magnitude and total HI linewidth) and to apply it in different wavebands since it is one of the most powerful extragalactic distance indicators. For a recent review and a recalibration using blue magnitudes see Richter and Huchtmeier (1984).

When the Bottinelli et al. version of the Tully-Fisher relation is applied to derive distances, and when the observed parameters are used to predict the Malmquist bias at a given distance, the observed variation of the Hubble ratio as a function of kinematic distance is about 2.5 times the predicted variation.

The degeneracy among the disk, bulge and halo contributions to galaxy rotation curves prevents an understanding of the distribution of baryons and dark matter in disk galaxies. In an attempt to break this degeneracy, we present an analysis of the spiral galaxy strong gravitational lens SDSS J2141-0001, discovered as part of the SLACS survey. We present new Hubble Space Telescope multicolor imaging, gas and stellar kinematics data derived from long-slit spectroscopy, and K-band LGS adaptive optics imaging, both from the Keck telescopes. We model the galaxy as a sum of concentric axisymmetric bulge, disk and halo components and infer the contribution of each component, using information from gravitational lensing and gas kinematics. This analysis yields a best-fitting total (disk plus bulge) stellar mass of log_{10}(Mstar/Msun) = 10.99(+0.11,-0.25). The photometric data combined with stellar population synthesis models yield log_{10}(Mstar/Msun) = 10.97\pm0.07, and 11.21\pm0.07 for the Chabrier and Salpeter IMFs, respectively. Accounting for the expected gas fraction of \simeq 20% reduces the lensing plus kinematics stellar mass by 0.10\pm0.05 dex, resulting in a Bayes factor of 11.9 in favor of a Chabrier IMF. The dark matter halo is roughly spherical, with minor to major axis ratio q_{halo}=0.91(+0.15,-0.13). The dark matter halo has a maximum circular velocity of V_{max}=276(+17,-18) km/s, and a central density parameter of log_{10}\Delta_{V/2}=5.9(+0.9,-0.5). This is higher than predicted for uncontracted dark matter haloes in LCDM cosmologies, log_{10}\Delta_{V/2}=5.2, suggesting that either the halo has contracted in response to galaxy formation, or that the halo has a higher than average concentration. At 2.2 disk scale lengths the dark matter fraction is f_{DM}=0.55(+0.20,-0.15), suggesting that SDSS J2141-0001 is sub-maximal., Comment: 24 pages, 20 figures, accepted to MNRAS, minor changes

The Tully-Fisher relation (TFR) links the stellar mass of a disk galaxy, $M_{\rm str}$, to its rotation speed: it is well approximated by a power law, shows little scatter, and evolves weakly with redshift. The relation has been interpreted as reflecting the mass-velocity scaling ($M\propto V^3$) of dark matter halos, but this interpretation has been called into question by abundance-matching (AM) models, which predict the galaxy-halo mass relation to be non-monotonic and rapidy evolving. We study the TFR of luminous spirals and its relation to AM using the EAGLE set of $\Lambda$CDM cosmological simulations. Matching both relations requires disk sizes to satisfy constraints given by the concentration of halos and their response to galaxy assembly. EAGLE galaxies approximately match these constraints and show a tight mass-velocity scaling that compares favourably with the observed TFR. The TFR is degenerate to changes in galaxy formation efficiency and the mass-size relation; simulations that fail to match the galaxy stellar mass function may fit the observed TFR if galaxies follow a different mass-size relation. The small scatter in the simulated TFR results because, at fixed halo mass, galaxy mass and rotation speed correlate strongly, scattering galaxies along the main relation. EAGLE galaxies evolve with lookback time following approximately the prescriptions of AM models and the observed mass-size relation of bright spirals, leading to a weak TFR evolution consistent with observation out to $z=1$. $\Lambda$CDM models that match both the abundance and size of galaxies as a function of stellar mass have no difficulty reproducing the observed TFR and its evolution., Comment: 12 pages, 7 figures, 1 table, submitted to MNRAS

We study the colour-magnitude relation (CMR) for a sample of 172 morphologically-classified E/S0 cluster galaxies from the ESO Distant Cluster Survey (EDisCS) at 0.4, Comment: 14 pages, 12 figures, accepted for publication in MNRAS

The accuracy of measurement of the Hubble constant depends not only on the accuracy of distance measurement but also on how small is the effect of local flows: The larger are redshifts of used galaxies, the higher is the accuracy of H0, if the error in distance measurement is comparable. The HI Tully-Fisher relation has been the standard tool for distance measurement up to cz ∼ 10,000 km s–1 (Tully and Fisher 1977), where, however, the local flow is not negligible.

We present a sky simulation of the atomic HI-emission line and the first 10 rotational CO emission lines of molecular gas in galaxies beyond the Milky Way. The simulated sky field has a comoving diameter of 500 Mpc/h; hence, the actual field-of-view depends on the (user-defined) maximal redshift zmax; e. g., for zmax=10, the field of view yields 4x4 deg^2. For all galaxies, we estimate the line fluxes, line profiles, and angular sizes of the Hi and CO-emission lines. The galaxy sample is complete for galaxies with cold hydrogen masses above 10^8 Msun. This sky simulation builds on a semi-analytic model of the cosmic evolution of galaxies in a Lambda-cold dark matter (Lambda CDM) cosmology. The evolving CDM distribution was adopted from the Millennium Simulation, an N-body CDM-simulation in a cubic box with a side length of 500 Mpc/h. This side length limits the coherence scale of our sky simulation: it is long enough to allow the extraction of the baryon acoustic oscillations in the galaxy power spectrum, yet the position and amplitude of the first acoustic peak will be imperfectly defined. This sky simulation is a tangible aid to the design and operation of future telescopes, such as the Square Kilometre Array, Large Millimeter Telescope, and Atacama Large Millimeter/submillimeter Array. The results presented in this paper have been restricted to a graphical representation of the simulated sky and fundamental dN/dz-analyses for peak flux density limited and total flux limited surveys of Hi and CO. A key prediction is that HI will be harder to detect at redshifts z>2 than predicted by a no-evolution model. The future verification or falsification of this prediction will allow us to qualify the semi-analytic models.

On a utilise un echantillon de 255 galaxies Sab a Scd dont les magnitudes B T 0 et les largeurs de la raie a 21 cm sont connues avec precision pour etudier l'augmentation apparente de la constante de Hubble par rapport aux distances cinematiques

Because the fraction of dark matter in spiral galaxies varies with luminosity, or for a number of other possible reasons, the relation between infrared luminosity and velocity width has previously been shown to be nonlinear. The relation between surface brightness and velocity width is now demonstrated to be nonlinear also. When these nonlinearities are taken into account, an apparent trend in surface brightness of cluster spirals with redshift is shown to be spurious. Apparent correlations of surface brightness and slope on cluster richness and cluster velocity dispersion also disappear. Neither this effect, nor an apparent trend in slope of the infrared Tully-Fisher relation with Hubble type, in themselves imply that the Tully-Fisher relation depends on the environment in which galaxies are located. 26 refs.

Estimates of the amplitude of scatter in the Tully-Fisher relation and estimates of the distance to the Virgo cluster are examined. It is suggested that the 0.7-mag scatter in the Tully-Fisher relation reported by Kraan-Korteweg et al. (1988) must be reexamined. The assumptions of Kraan-Korteweg et al. and of Pierce and Tully (1988) are applied to a sample of 131 galaxies. It is found that the use of different subsets of calibrator galaxies by the two studies produces distance estimates which are consistent with the data, although the predicted distance modulus differs by 0.6 mag. It is concluded that no agreement can be reached on the distance of the Virgo cluster derived from the Tully-Fisher relation for spiral galaxies as long as there is no agreement on inclination corrections to magnitudes, diameters, and rotation velocities. 22 refs.

We consider a model for the velocity field of the Local Supercluster which includes both the deceleration of galaxies by a spherically symmetric density enhancement and a random motion of the Local Group with respect to nearby galaxies. We adjust the free parameters in the model to minimize scatter about the infrared luminosity--H I velocity width relation (the ''IR Tylly-Fisher relation'') yielding a best estimate for the amplitude of the deceleration pattern at the position of the Local Group of 250 +- 64 km s/sup -1/, with a total velocity toward the Virgo cluster of 331 +- 41 km s/sup -1/. Several potential systematic errors (some of which have not been heretofore recognized) required careful attention in the course of obtaining these estimates. Where it proved possible, these have been minimized by selective pruning of our sample, and the remaining systematic errors calibrated with Monte Carlo Experiments. We find a significant reduction in amplitude of our residuals if we test for differential rotation about the center of the Supercluster, with an estimate of the amplitude of the adopted pattern of 180 +- 58 km s/sup -1/ at the position of the Local Group. We find small reductions in the scattermore » about the IR Tully-Fisher relation both when we consider correlations of velocity width and luminosity with morphological type, surface brightness, and optical to H I flux ratio and when we allow the log ..delta..V-log L/sub IR/ relation to be nonlinear. The derived total velocity with respect to the Supercluster shows better agreement with the velocity inferred from the 3 K background dipole anisotropy than has been previously obtained but with some remaining differences.« less

The Large Early Galaxy Census (LEGA-C) is a Public Spectroscopic Survey of $\sim3200$ $K$-band selected galaxies at redshifts $z=0.6-1.0$ with stellar masses M_star > 1e10M_sun, conducted with VIMOS on ESO's Very Large Telescope. The survey is embedded in the COSMOS field ($R.A. = 10h00$; $Dec.=+2��$). The 20-hour long integrations produce high-$S/N$ continuum spectra that reveal ages, metallicities and velocity dispersions of the stellar populations. LEGA-C's unique combination of sample size and depth will enable us for the first time to map the stellar content at large look-back time, across galaxies of different types and star-formation activity. Observations started in December 2014 and are planned to be completed by mid 2018, with early data releases of the spectra and value-added products. In this paper we present the science case, the observing strategy, an overview of the data reduction process and data products, and a first look at the relationship between galaxy structure and spectral properties, as it existed 7 Gyr ago., Accepted for publication in ApJS - LEGA-C website: http://www.mpia.de/home/legac/index.html