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Публикации по объекту
An Integrated Spectrophotometric Survey of Nearby Star-forming Galaxies
We present integrated optical spectrophotometry for a sample of 417nearby galaxies. Our observations consist of spatially integrated,S/N=10-100 spectroscopy between 3600 and 6900 Å at ~8 Å FWHMresolution. In addition, we present nuclear (2.5"×2.5")spectroscopy for 153 of these objects. Our sample targets a diverserange of galaxy types, including starbursts, peculiar galaxies,interacting/merging systems, dusty, infrared-luminous galaxies, and asignificant number of normal galaxies. We use population synthesis tomodel and subtract the stellar continuum underlying the nebular emissionlines. This technique results in emission-line measurements reliablycorrected for stellar absorption. Here we present the integrated andnuclear spectra, the nebular emission-line fluxes and equivalent widths,and a comprehensive compilation of ancillary data available in theliterature for our sample. In a series of subsequent papers we use thesedata to study optical star formation rate indicators, nebular abundancediagnostics, the luminosity-metallicity relation, the dust properties ofnormal and starburst galaxies, and the star formation histories ofinfrared-luminous galaxies.
| The Difference between the α-disks of Seyfert 1 Galaxies and Quasars
In a previous paper, it was suggested that contamination of the nuclearluminosity by the host galaxy plays an important role in determining theparameters of the standard α disk of AGNs. Using the nuclearabsolute B band magnitude instead of the total absolute B bandmagnitude, we have recalculated the central black hole masses, accretionrates and disk inclinations for 20 Seyfert 1 galaxies and 17Palomar-Green (PG) quasars. It is found that a small value of αis needed for the Seyfert 1 galaxies than for the PG quasars. Thisdifference in α possibly leads to the different properties ofSeyfert 1 galaxies and quasars. Furthermore, we find most of the objectsin this sample are not accreting at super-Eddington rates if we adoptthe nuclear optical luminosity in our calculation.
| Near-infrared observations of galaxies in Pisces-Perseus. V. On the origin of bulges
We investigate the scaling relations of bulge and disk structuralparameters for a sample of 108 disk galaxies. Structural parameters ofindividual galaxies are obtained from two-dimensional bulge/diskdecomposition of their H-band surface brightness distributions. Bulgesare modelled with a generalized exponential (Sérsic) withvariable integer shape index n. We find that bulge effectivescalelengths reB and luminosity MBincrease with increasing n, but disk properties are independent of bulgeshape. As Hubble type T increases, bulges become less luminous and theirmean effective surface brightness <μeB>gets fainter; disk <μeD> shows a similar,but much weaker, trend. When bulge parameters(<μeB>, reB,MB) are compared with disk ones(<μeD>, reD,MD), they are tightly correlated for n=1 bulges. Thecorrelations gradually worsen with increasing n such that n=4 bulgesappear virtually independent of their disks. The Kormendy relation,<μeB> vs. reB, isshown to depend on bulge shape n; the two parameters are tightlycorrelated in n=4 bulges (r=0.8), and increasingly less so as ndecreases; disk <μeD> andreD are well correlated (r=0.7). Bulge-to-disksize ratios reB/reD areindependent of Hubble type, but smaller for exponential bulges; the meanreB/reD for n=1 bulges is 4times smaller than that for n=4, with a spread which is 9 times smaller.Strongly barred SB galaxies with exponential bulges are more luminousthan their unbarred counterparts. Exponential bulges appear to beclosely related to their underlying disks, while bulges with higher nvalues are less so; n=4 bulges and their disks apparently have norelation. We interpret our results as being most consistent with asecular evolutionary scenario, in which dissipative processes in thedisk are responsible for building up the bulges in most spirals.Based on observations at the TIRGO, NOT, and VATT telescopes. TIRGO(Gornergrat, CH) is operated by IRA-CNR, Arcetri, Firenze. NOT (LaPalma, Canary Islands) is operated by NOTSA, the Nordic ObservatoryScientific Association. VATT (Mt. Graham, AZ) is operated by VORG, theVatican Observatory Research Group.Full Table 1 is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/414/905.
| Bar Galaxies and Their Environments
The prints of the Palomar Sky Survey, luminosity classifications, andradial velocities were used to assign all northern Shapley-Ames galaxiesto either (1) field, (2) group, or (3) cluster environments. Thisinformation for 930 galaxies shows no evidence for a dependence of barfrequency on galaxy environment. This suggests that the formation of abar in a disk galaxy is mainly determined by the properties of theparent galaxy, rather than by the characteristics of its environment.
| The QDOT all-sky IRAS galaxy redshift survey
We describe the construction of the QDOT survey, which is publiclyavailable from an anonymous FTP account. The catalogue consists ofinfrared properties and redshifts of an all-sky sample of 2387 IRASgalaxies brighter than the IRAS PSC 60-μm completeness limit(S_60>0.6Jy), sparsely sampled at a rate of one-in-six. At |b|>10deg, after removing a small number of Galactic sources, the redshiftcompleteness is better than 98per cent (2086/2127). New redshifts for1401 IRAS sources were obtained to complete the catalogue; themeasurement and reduction of these are described, and the new redshiftstabulated here. We also tabulate all sources at |b|>10 deg with noredshift so far, and sources with conflicting alternative redshiftseither from our own work, or from published velocities. A list of 95ultraluminous galaxies (i.e. with L_60μm>10^12 L_solar) is alsoprovided. Of these, ~20per cent are AGN of some kind; the broad-lineobjects typically show strong Feii emission. Since the publication ofthe first QDOT papers, there have been several hundred velocity changes:some velocities are new, some QDOT velocities have been replaced by moreaccurate values, and some errors have been corrected. We also present anew analysis of the accuracy and linearity of IRAS 60-μm fluxes. Wefind that the flux uncertainties are well described by a combination of0.05-Jy fixed size uncertainty and 8per cent fractional uncertainty.This is not enough to cause the large Malmquist-type errors in the rateof evolution postulated by Fisher et al. We do, however, find marginalevidence for non-linearity in the PSC 60-μm flux scale, in the sensethat faint sources may have fluxes overestimated by about 5per centcompared with bright sources. We update some of the previous scientificanalyses to assess the changes. The main new results are as follows. (1)The luminosity function is very well determined overall but is uncertainby a factor of several at the very highest luminosities(L_60μm>5x10^12L_solar), as this is where the remainingunidentified objects are almost certainly concentrated. (2) Thebest-fitting rate of evolution is somewhat lower than our previousestimate; expressed as pure density evolution with density varying as(1+z)^p, we find p=5.6+/-2.3. Making a rough correction for the possible(but very uncertain) non-linearity of fluxes, we find p=4.5+/-2.3. (3)The dipole amplitude decreases a little, and the implied value of thedensity parameter, assuming that IRAS galaxies trace the mass, isΩ=0.9(+0.45, -0.25). (4) Finally, the estimate of density varianceon large scales changes negligibly, still indicating a significantdiscrepancy from the predictions of simple cold dark matter cosmogonies.
| 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.
| The I-Band Tully-Fisher Relation for SC Galaxies: 21 Centimeter H I Line Data
A compilation of 21 cm line spectral parameters specifically designedfor application of the Tully-Fisher (TF) distance method is presentedfor 1201 spiral galaxies, primarily field Sc galaxies, for which opticalI-band photometric imaging is also available. New H I line spectra havebeen obtained for 881 galaxies. For an additional 320 galaxies, spectraavailable in a digital archive have been reexamined to allow applicationof a single algorithm for the derivation of the TF velocity widthparameter. A velocity width algorithm is used that provides a robustmeasurement of rotational velocity and permits an estimate of the erroron that width taking into account the effects of instrumental broadeningand signal-to-noise. The digital data are used to establish regressionrelations between measurements of velocity widths using other commonprescriptions so that comparable widths can be derived throughconversion of values published in the literature. The uniform H I linewidths presented here provide the rotational velocity measurement to beused in deriving peculiar velocities via the TF method.
| The I-Band Tully-Fisher Relation for SC Galaxies: Optical Imaging Data
Properties derived from the analysis of photometric I-band imagingobservations are presented for 1727 inclined spiral galaxies, mostly oftypes Sbc and Sc. The reduction, parameter extraction, and errorestimation procedures are discussed in detail. The asymptotic behaviorof the magnitude curve of growth and the radial variation in ellipticityand position angle are used in combination with the linearity of thesurface brightness falloff to fit the disk portion of the profile. TotalI-band magnitudes are calculated by extrapolating the detected surfacebrightness profile to a radius of eight disk scale lengths. Errors inthe magnitudes, typically ~0.04 mag, are dominated by uncertainties inthe sky subtraction and disk-fitting procedures. Comparison is made withthe similar imaging database of Mathewson, Ford, & Buchhorn, both aspresented originally by those authors and after reanalyzing theirdigital reduction files using identical disk-fitting procedures. Directcomparison is made of profile details for 292 galaxies observed incommon. Although some differences occur, good agreement is found,proving that the two data sets can be used in combination with onlyminor accommodation of those differences. The compilation of opticalproperties presented here is optimized for use in applications of theTully-Fisher relation as a secondary distance indicator in studies ofthe local peculiar velocity field.
| Near-infrared observations of galaxies in Pisces-Perseus. I. vec H-band surface photometry of 174 spiral
We present near-infrared, H-band (1.65 $() μm), surface photometry of174 spiral galaxies in the area of the Pisces-Perseus supercluster. Theimages, acquired with the ARNICA camera mounted on various telescopes,are used to derive radial profiles of surface brightness, ellipticities,and position angles, together with global parameters such as H-bandmagnitudes and diameters Radial profiles in tabular form and images FITSfiles are also available upon request from gmorio@arcetri.astro.it.}.The mean relation between H-band isophotal diameter D_{21.5} and theB-band D25 implies a B-H color of the outer disk bluer than3.5; moreover, D_{21.5}/D25 depends on (global) color andabsolute luminosity. The correlations among the various photometricparameters suggest a ratio between isophotal radius D_{21.5}/2 and diskscale length of ~ m3.5 and a mean disk central brightness ~ meq 17.5H-mag arcsec^{-2}. We confirm the trend of the concentration indexC31$ with absolute luminosity and, to a lesser degree, withmorphological type. We also assess the influence of non-axisymmetricstructures on the radial profiles and on the derived parameters. Basedon observations at the TIRGO, NOT, and VATT telescopes. TIRGO(Gornergrat, CH) is operated by CAISMI-CNR, Arcetri, Firenze. NOT (LaPalma, Canary Islands) is operated by NOTSA, the Nordic ObservatoryScientific Association. VATT (Mt. Graham, Az) is operated by VORG, theVatican Observatory Research Group Table 3 and Fig. 4 are only availablein electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html.
| Catalogue of HI maps of galaxies. I.
A catalogue is presented of galaxies having large-scale observations inthe HI line. This catalogue collects from the literature the informationthat characterizes the observations in the 21-cm line and the way thatthese data were presented by means of maps, graphics and tables, forshowing the distribution and kinematics of the gas. It containsfurthermore a measure of the HI extension that is detected at the levelof the maximum sensitivity reached in the observations. This catalogueis intended as a guide for references on the HI maps published in theliterature from 1953 to 1995 and is the basis for the analysis of thedata presented in Paper II. The catalogue is only available inelectronic form at the CDS via anonymous ftp 130.79.128.5 orhttp://cdsweb.u-strasbg.fr/Abstract.html
| Total magnitude, radius, colour indices, colour gradients and photometric type of galaxies
We present a catalogue of aperture photometry of galaxies, in UBVRI,assembled from three different origins: (i) an update of the catalogueof Buta et al. (1995) (ii) published photometric profiles and (iii)aperture photometry performed on CCD images. We explored different setsof growth curves to fit these data: (i) The Sersic law, (ii) The net ofgrowth curves used for the preparation of the RC3 and (iii) A linearinterpolation between the de Vaucouleurs (r(1/4) ) and exponential laws.Finally we adopted the latter solution. Fitting these growth curves, wederive (1) the total magnitude, (2) the effective radius, (3) the colourindices and (4) gradients and (5) the photometric type of 5169 galaxies.The photometric type is defined to statistically match the revisedmorphologic type and parametrizes the shape of the growth curve. It iscoded from -9, for very concentrated galaxies, to +10, for diffusegalaxies. Based in part on observations collected at the Haute-ProvenceObservatory.
| Molecular Gas, Morphology, and Seyfert Galaxy Activity
We probe the cause of the elevated star formation in host galaxies ofSeyfert 2 nuclei compared with Seyfert 1 hosts and with field galaxies.12CO (1--0) observations of a large sample of Seyfert galaxies indicateno significant difference in the total amount of molecular gas as afunction of the Seyfert nuclear type, nor are Seyfert galaxiessignificantly different in this regard from a sample of field galaxiesonce selection effects are accounted for. Therefore, the total amount ofmolecular gas is not responsible for the enhanced star-forming activityin Seyfert 2 hosts. To probe how this gas is being converted moreefficiently into stars in Seyfert 2 hosts than in the other galaxies, weinvestigate the occurrence of bars, interactions, and distortedmorphologies among Seyfert galaxies. We find a significantly higher rateof asymmetric morphologies for Seyfert 2 galaxies with respect toSeyfert 1 galaxies and field galaxies. Relative to field galaxies, theeffect is at a greater than 99.9% confidence level. The presence ofasymmetric morphologies in individual Seyfert galaxies is correlatedwith their tendency to exhibit enhanced star-forming activity. Theseresults suggest that asymmetric morphologies are an important cause forthe link between Seyfert type and star-forming activity: bars anddistortions in Seyfert 2 hosts are likely both to enhance star-formingactivity and to funnel gas into the nuclear region, thus obscuring andpossibly contributing to the feeding of the active nucleus.
| 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.
| A Preliminary Classification Scheme for the Central Regions of Late-Type Galaxies
The large-scale prints in The Carnegie Atlas of Galaxies have been usedto formulate a classification scheme for the central regions oflate-type galaxies. Systems that exhibit small bright central bulges ordisks (type CB) are found to be of earlier Hubble type and of higherluminosity than galaxies that do not contain nuclei (type NN). Galaxiescontaining nuclear bars, or exhibiting central regions that are resolvedinto individual stars and knots, and galaxies with semistellar nuclei,are seen to have characteristics that are intermediate between those oftypes CB and NN. The presence or absence of a nucleus appears to be auseful criterion for distinguishing between spiral galaxies andmagellanic irregulars.
| Integrated photoelectric magnitudes and color indices of bright galaxies in the Johnson UBV system
The photoelectric total magnitudes and color indices published in theThird Reference Catalogue of Bright Galaxies (RC3) are based on ananalysis of approximately equals 26,000 B, 25,000 B-V, and 17,000 U-Bmultiaperture measurements available up to mid 1987 from nearly 350sources. This paper provides the full details of the analysis andestimates of internal and external errors in the parameters. Thederivation of the parameters is based on techniques described by theVaucouleurs & Corwin (1977) whereby photoelectric multiaperture dataare fitted by mean Hubble-type-dependent curves which describe theintegral of the B-band flux and the typical B-V and U-B integrated colorgradients. A sophisticated analysis of the residuals of thesemeasurements from the curves was made to allow for the random andsystematic errors that effect such data. The result is a homogeneous setof total magnitudes BTA total colors(B-V)T and (U-B)T, and effective colors(B-V)e and (U-B)e for more than 3000 brightgalaxies in RC3.
| Arm structure in normal spiral galaxies, 1: Multivariate data for 492 galaxies
Multivariate data have been collected as part of an effort to develop anew classification system for spiral galaxies, one which is notnecessarily based on subjective morphological properties. A sample of492 moderately bright northern Sa and Sc spirals was chosen for futurestatistical analysis. New observations were made at 20 and 21 cm; thelatter data are described in detail here. Infrared Astronomy Satellite(IRAS) fluxes were obtained from archival data. Finally, new estimatesof arm pattern radomness and of local environmental harshness werecompiled for most sample objects.
| 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.
| The Hubble relation - Differences between galaxy types SB and SC
It is shown that the Sb galaxies have apparent magnitudes which varyalmost exactly as if their redshifts were a measure of the distance atwhich they are observed, while the Sc do not exhibit a linear Hubblerelation. An attempt is made to determine whether the Sc discordancefrom the Hubble law is caused by Malmquist bias operating in thisfainter luminosity class of galaxies or there are inherent fundamentalpeculiarities. To this purpose the search is undertaken for other kindsof galaxies physically associated which these deviating Sc's. It isshown that luminosity criterion (Tully-Fisher) gives much smallerdistances for these galaxies than their redshifts do. The interaction ofspecific high redshift ScI's with nearby galaxies is presented as anindependent proof that ScI's are generally small, low luminositygalaxies.
| The color of the inner regions of Seyfert galaxies compared with normal galaxies
For homogeneous samples of 57 Seyfert and 79 normal galaxies, the (U-B)0and (B-V)0 color indices are determined for inner regions in rings witha mean radius of about 4 kpc. It is found that the E/S0-Sbc-type Seyfertgalaxies are bluer in (U-B)0 than similar normal galaxies. The positionof Seyfert galaxy rings on a two-color diagram reveals larger scatteringand a more systematic shift of points compared with the normal colorsequence of galaxies. It is suggested that these peculiarities arerelated to bursts of star formation and, in some objects, to large (B-V)color excesses in the inner part of the galaxy.
| Integrated colors and luminosity of Seyfert host galaxies - A comparison with the photometric characteristics of normal galaxies
Not Available
| An Arecibo survey for extragalactic hydroxyl absorption. I - Presentation of results
Hydroxyl absorption has been detected in a total of 24 galaxies;megamaser emission in six additional galaxies brings the total number ofdetections of extragalactic OH to 30. About 50 percent of theextragalactic absorption lines are asymmetrically skewed toward the red,indicating that the molecular disks could have an unusual velocity orexcitation structure. The hyperfine ratio for the 1667 and 1665 MHztransitions in most galaxies lies within the limits specified by LTEconditions.
| A catalog of 2810 nearby galaxies - The effect of the Virgocentric flow model on their observed velocities
A catalog of 2810 nearby galaxies is constructed on the basis of threesubcatalogs: galaxies with B(T) less than or equal to 13.4 mag, galaxieswith v0 less than or equal to 500 km/s, and galaxies having B(T) lessthan or equal to 14.95 mag and lying within a 10-deg cone around M87.The data are compiled in tables and graphs and characterized in detail.The distances to objects with known red shifts are determined in unitsof the Virgo-cluster distance, independent of H0, using two versions ofthe nonlinear Virgocentric-flow models of Silk (1974 and 1977) and shownto correspond to local Virgo-inflow rates of 220 and 440 km/s,respectively. The luminous-galaxy distribution is described as acell-like structure with several superclusters, chains ofinterconnecting galaxies, and large voids.
| The Malmquist bias and the value of H0 from the Tully-Fisher relation
A large sample (n = 395) of spiral (Sab to Sd type) galaxies havingcorrected apparent magnitudes B-zero-sub-T and 21-cm line data (HI linewidths and radial velocities) is used to investigate in a new way theinfluence of the Malmquist bias on the determination of theextragalactic distance scale and the Hubble constant derived from theapplication of the B-band Tully-Fisher relation. This effect is clearlyidentified by using relative kinematic distances derived from aclassical local velocity field model and the concept of normalizedrelative kinematic distance. It results in an unbiased estimate of theHubble constant H0 which appears quite insensitive to the parameters(mean velocity of Virgo and infall velocity of the Local Group towardVirgo) adapted for the local velocity field model. A similar effect isfound from a sample of galaxies (n = 72) which are 'sosies' of 14primary galaxies. It is suggested that the presently derived H0represents the global value of the Hubble constant.
| Arecibo H I data for 136 spiral galaxies
The results of observations of the neutral hydrogen emission of 136spiral galaxies observed using the 21 cm spectral-line system of theArecibo Observatory are presented. Most of the 114 detected objects havebeen mapped along the major axis, and cumulative spectra andposition-velocity contour maps for each of them are presented. The dataare used to determine the overall H I content, systemic velocity, linewidths, and scale-length H I diameters. Data are also presented, indetailed tabular form, for each of the positions observed on thedetected objects.
| An apparent increase of the Hubble constant with velocities of the determining galaxies
A study is conducted of the variation of the Hubble constant derivedfrom the Bottinelli et al. (1983) version of the Tully-Fisher relationwith respect to kinematic distances D(v) in an infall model towardVirgo. The sample of 256 galaxies used encompasses types Sab to Sd. Itis noted that, before or after correction of the type effect, the Hubbleconstant increases from approximately log H(0) of 1.78 at D(v) of 250km/sec to 2.08 at 5000 km/sec. Attention is given to such differentpossible explanations for this as galactic extinction, the Malmquistbias, TF relation slope, and an inadequate model.
| H I line studies of galaxies. III - Distance moduli of 822 disk galaxies
The distance scale established on the basis of a distance moduli catalog(for 822 galaxies) that was derived from 21-cm line widths via theB-band Tully-Fisher relation is compared with several independent scaleshaving a common zero point, that are based on the indicators forluminosity index, redshift, ring diameters, brightest superassociations,and effective diameters. These are in excellent systematic agreement,and confirm the linearity of the H I scale in the 24-35 modulusinterval, but indicate a small systematic zero point difference of about0.2 mag, which must be added to the H I moduli to place them on the same'short' distance scale defined by the others.
| 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.
| A radio continuum survey of nearby galaxies. I - Observations at 0.4, 0.8, 4.8, and 10.7 GHz
Observations have been conducted of a total of 136 galaxies at one ormore of four frequencies: 430, 834, 4750, and 10,700 MHz. For a subsetof these, spectral indices could be determined. A mean value alpha =-0.68 + or - 0.04 is found over the whole frequency range covered. Themean high frequency spectral index (4.9-10.7 GHz) for Sc galaxies isalpha = -0.55 + or - 0.07, which indicates the presence of significantamounts of thermal emission in a considerable fraction of the sample. At10.7 GHz the mean thermal contribution to the radio emission of thesample Sc galaxies is 35 + or - 15 percent; for the sample Sb galaxiesthis is 20 + or - 15 percent.
| Index of galaxy spectra.
Not Available
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