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Dark matter in the inner parts of barred galaxies: The data
This paper presents surface photometry (B,V,I,J,H,K) and Hαrotation curves of 27 isolated spiral galaxies. The final goal is toobtain the mass distribution of a sample of isolated spiral galaxies inorder to model their gas kinematics. This is then compared to theobserved rotation curve, to determine the necessity of a dark halo inthe inner parts (Perez et al. 2004, A&A, 424, 799). The azimuthallyaveraged radial surface brightness profiles and the integratedmagnitudes obtained from ellipse fitting are given for each of thesample galaxies. The ellipse fitting technique applied to the lightdistribution also allowed us to obtain the size of the bar, and theinclination and position angle of the outer isophotes that allow thegalaxy deprojection. Using these profiles, 1-D disk-bulge decompositionwas performed to obtain the disk scale-length and the bulge effectiveradius for the different bands. Through the fitting of a parametricfunction to the observed rotation curve, the maximum rotational velocityand the corresponding radius was obtained. The correlation between thebulge and disk parameters is in agreement with previous studies (de Jong1996a, A&A, 313, 45; Márquez & Moles 1999, A&A, 344,421; Baggett et al. 1998, AJ, 116, 1626). Regarding the Kormendyrelation (Kormendy 1977, ApJ, 218, 333), in agreement with de Jong, nocorrelation between the bulge effective radius and its surfacebrightness is found, possibly due to the small range of bulge magnitudescovered. We find a smaller scatter in the structural relations whencompared to non-isolated samples in agreement with Márquez &Moles (1999). Finally, a correlation between the disk scale-length andthe bar size is observed, possibly reflecting the rapid growth of a bar.
| Gas flow and dark matter in the inner parts of early-type barred galaxies. I. SPH simulations and comparison with the observed kinematics
This paper presents the dynamical simulations run in the potentialderived from the light distribution of 5 late-type barred spiralgalaxies (IC 5186, NGC 5728,NGC 7267, NGC 7483 and NGC 5505). The aim is to determine whether the massdistribution together with the hydrodynamical simulations can reproducethe observed line-of-sight velocity curves and the gas morphology in theinner regions of these barred galaxies. The light distribution isobtained from the H-band and the I-band combined. The M/L is determinedusing population synthesis models. The observations and the methodologyof the mass distribution modelling are presented in a companion paper.The SPH models using the stellar mass models obtained directly from theH-band light distributions give a good representation of the gasdistribution and dynamics of the modelled galaxies, supporting themaximum disk assumption. This result indicates that the gravitationalfield in the inner region is mostly provided by the stellar luminouscomponent. When 40% of the total mass is transferred to an axisymmetricdark halo, the modelled kinematics clearly depart from the observedkinematics, whereas the departures are negligible for dark mass halos of5% and 20% of the total mass. This result sets a lower limit for thecontribution of the luminous component of about 80%, which is inagreement with the maximum disk definition of the stellar masscontribution to the rotation curve (about 85% ± 10). This resultis in agreement with the results found by \citet{weiner01} forNGC 4123 using a similar methodology. For twogalaxies, NGC 7483 and IC 5186, a very good agreement with the observeddata is found. In these cases the non-circular motions can help to breakthe disk-halo degeneracy. For the other three galaxies (NGC 5728, NGC7267 and NGC 5505) no definite results are found: for NGC 7267 and NGC5505 no steady state is reached in the simulations and for NGC 5728there is no good agreement with the observed kinematics, possibly due tothe presence of a secondary bar decoupled from the primary. However, forthis latter galaxy the M/L ratio used gives the right amplitude of therotation curve, in further support of the M/L calculation method usedthroughout this work. Fast bars give the best fit to the observedkinematics for NGC 7483 and IC 5186 with corotation at the end of thebar for NGC 7483 and at 1.4× Rbar for IC 5186. For NGC5505 for which no steady state configuration is found, the addition of arigid halo stabilises the gas flows but the derived kinematics does notfit well the observations.Figures \ref{fig:vel1}-\ref{fig:Lz_IC5186}, \ref{fig:mask_height},\ref{fig:height_rc}, \ref{fig:rc_NGC5728}, \ref{fig:pv_NGC7483},\ref{fig:substract_NGC7483}, \ref{fig:mask_dm}, \ref{fig:dm_rc} and\ref{fig:ngc5505_dm_rc} are only available in electronic form athttp://www.edpsciences.org}
| The UZC-SSRS2 Group Catalog
We apply a friends-of-friends algorithm to the combined Updated ZwickyCatalog and Southern Sky Redshift Survey to construct a catalog of 1168groups of galaxies; 411 of these groups have five or more members withinthe redshift survey. The group catalog covers 4.69 sr, and all groupsexceed the number density contrast threshold, δρ/ρ=80. Wedemonstrate that the groups catalog is homogeneous across the twounderlying redshift surveys; the catalog of groups and their membersthus provides a basis for other statistical studies of the large-scaledistribution of groups and their physical properties. The medianphysical properties of the groups are similar to those for groupsderived from independent surveys, including the ESO Key Programme andthe Las Campanas Redshift Survey. We include tables of groups and theirmembers.
| Arcsecond Positions of UGC Galaxies
We present accurate B1950 and J2000 positions for all confirmed galaxiesin the Uppsala General Catalog (UGC). The positions were measuredvisually from Digitized Sky Survey images with rms uncertaintiesσ<=[(1.2")2+(θ/100)2]1/2,where θ is the major-axis diameter. We compared each galaxymeasured with the original UGC description to ensure high reliability.The full position list is available in the electronic version only.
| An image database. II. Catalogue between δ=-30deg and δ=70deg.
A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect.
| The far-infrared properties of the CfA galaxy sample. I - The catalog
IRAS flux densities are presented for all galaxies in the Center forAstrophysics magnitude-limited sample (mB not greater than 14.5)detected in the IRAS Faint Source Survey (FSS), a total of 1544galaxies. The detection rate in the FSS is slightly larger than in thePSC for the long-wavelength 60- and 100-micron bands, but improves by afactor of about 3 or more for the short wavelength 12- and 25-micronbands. This optically selected sample consists of galaxies which are, onaverage, much less IR-active than galaxies in IR-selected samples. Itpossesses accurate and complete redshift, morphological, and magnitudeinformation, along with observations at other wavelengths.
| High signal-to-noise ratio observations of H I in 243 galaxies
The 21 cm spectral-line system of the Arecibo Observatory was used tomeasure neutral hydrogen emission from 243 faint galaxies. Most lie nearthe plane of the Local Supercluster. All observations reach anunsmoothed signal-to-noise ratio of at least 7.0; the average for theset is 23. The resulting data are used to estimate H I masses, systemicvelocities, and accurate profile widths at 20 percent, 25 percent, 50percent, and 80 percent of peak intensity levels. The widths are used tocalibrate directly the bias introduced by popular data-smoothingoperation. The data include observations of 65 objects with previouslyunknown redshifts.
| A survey of galaxy redshifts. IV - The data
The complete list of the best available radial velocities for the 2401galaxies in the merged Zwicky-Nilson catalog brighter than 14.5mz and with b (II) above +40 deg or below -30 deg ispresented. Almost 60 percent of the redshifts are from the CfA surveyand are accurate to typically 35 km/s.
| Velocity calibration of the Las Campanas redshift survey
The Center for Astrophysics redshift survey is being extended bySchectman et al. (1983) to the south galactic cap. Their initial resultsprovide independent estimates of both emission Ve velocities and theabsorption line Vc velocities, such that (Ve-Vc) = 54 + or - 13 km/s. HI line observations of 40 of the sample are presented here, to provide asecure velocity scale calibration. The Vc velocities are found to have a32 + or - 9 km/s zero-point error.
| Redshifts for 115 galaxies near the equator
New redshifts for 115 bright galaxies located near the celestial equatorare reported. The spectra were observed with a blue-sensitivephoton-counting Reticon on the 100-in. DuPont telescope, and theredshifts were derived using the data-analysis system developed for theCfA Redshift Survey. Comparisons with other measured redshifts suggestthat these data are similar in quality to the redshifts measured at Mt.Hopkins for the CfA Redshift Survey; the velocity zero point is good to10 or 15 km/s, with a typical error of 35 km/s for the individualmeasurements.
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