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The Distribution of Bar and Spiral Arm Strengths in Disk Galaxies
The distribution of bar strengths in disk galaxies is a fundamentalproperty of the galaxy population that has only begun to be explored. Wehave applied the bar-spiral separation method of Buta and coworkers toderive the distribution of maximum relative gravitational bar torques,Qb, for 147 spiral galaxies in the statistically well-definedOhio State University Bright Galaxy Survey (OSUBGS) sample. Our goal isto examine the properties of bars as independently as possible of theirassociated spirals. We find that the distribution of bar strengthdeclines smoothly with increasing Qb, with more than 40% ofthe sample having Qb<=0.1. In the context of recurrent barformation, this suggests that strongly barred states are relativelyshort-lived compared to weakly barred or nonbarred states. We do notfind compelling evidence for a bimodal distribution of bar strengths.Instead, the distribution is fairly smooth in the range0.0<=Qb<0.8. Our analysis also provides a first look atspiral strengths Qs in the OSUBGS sample, based on the sametorque indicator. We are able to verify a possible weak correlationbetween Qs and Qb, in the sense that galaxies withthe strongest bars tend to also have strong spirals.
| New H2O masers in Seyfert and FIR bright galaxies
Using the Effelsberg 100-m telescope, detections of four extragalacticwater vapor masers are reported. Isotropic luminosities are ~50, 1000, 1and 230 Lȯ for Mrk 1066 (UGC 2456), Mrk 34, NGC 3556 andArp 299, respectively. Mrk 34 contains by far the most distant and oneof the most luminous water vapor megamasers so far reported in a Seyfertgalaxy. The interacting system Arp 299 appears to show two maserhotspots separated by approximately 20´´. With these newresults and even more recent data from Braatz et al. (2004, ApJ, 617,L29), the detection rate in our sample of Seyferts with known jet-NarrowLine Region interactions becomes 50% (7/14), while in star forminggalaxies with high (S100~μ m>50 Jy) far infrared fluxesthe detection rate is 22% (10/45). The jet-NLR interaction sample maynot only contain “jet-masers” but also a significant numberof accretion “disk-masers” like those seen in NGC 4258. Astatistical analysis of 53 extragalactic H2O sources (excluding theGalaxy and the Magellanic Clouds) indicates (1) that the correlationbetween IRAS Point Source and H2O luminosities, established forindividual star forming regions in the galactic disk, also holds forAGN-dominated megamaser galaxies; (2) that maser luminosities are notcorrelated with 60 μm/100 μm color temperatures; and (3) that onlya small fraction of the luminous megamasers (L_H_2O > 100Lȯ) detectable with 100-m sized telescopes have so farbeen identified. The H2O luminosity function (LF) suggests that thenumber of galaxies with 1 Lȯ < L_H_2O < 10Lȯ, the transition range between“kilomasers” (mostly star formation) and“megamasers” (active galactic nuclei), is small. The overallslope of the LF, ~-1.5, indicates that the number of detectable masersis almost independent of their luminosity. If the LF is not steepeningat very high maser luminosities and if it is possible to find suitablecandidate sources, H2O megamasers at significant redshifts should bedetectable even with present day state-of-the-art facilities.
| Bar-induced perturbation strengths of the galaxies in the Ohio State University Bright Galaxy Survey - I
Bar-induced perturbation strengths are calculated for a well-definedmagnitude-limited sample of 180 spiral galaxies, based on the Ohio StateUniversity Bright Galaxy Survey. We use a gravitational torque method,the ratio of the maximal tangential force to the mean axisymmetricradial force, as a quantitative measure of the bar strength. Thegravitational potential is inferred from an H-band light distribution byassuming that the M/L ratio is constant throughout the disc. Galaxiesare deprojected using orientation parameters based on B-band images. Inorder to eliminate artificial stretching of the bulge, two-dimensionalbar-bulge-disc decomposition has been used to derive a reliable bulgemodel. This bulge model is subtracted from an image, the disc isdeprojected assuming it is thin, and then the bulge is added back byassuming that its mass distribution is spherically symmetric. We findthat removing the artificial bulge stretch is important especially forgalaxies having bars inside large bulges. We also find that the massesof the bulges can be significantly overestimated if bars are not takeninto account in the decomposition.Bars are identified using Fourier methods by requiring that the phasesof the main modes (m= 2, m= 4) are maintained nearly constant in the barregion. With such methods, bars are found in 65 per cent of the galaxiesin our sample, most of them being classified as SB-type systems in thenear-infrared by Eskridge and co-workers. We also suggest that as muchas ~70 per cent of the galaxies classified as SAB-types in thenear-infrared might actually be non-barred systems, many of them havingcentral ovals. It is also possible that a small fraction of the SAB-typegalaxies have weak non-classical bars with spiral-like morphologies.
| Spatial distribution of galaxies in the Puppis region
We determine the spatial distribution of the galaxies located behind thepart of the zone of avoidance of the Milky Way defined by 220°
| Deprojecting spiral galaxies using Fourier analysis. Application to the Ohio sample
We use two new methods developed recently (Barberàet al.\cite{bar03}, A&A, 415, 849), as well as information obtained fromthe literature, to calculate the orientation parameters of the spiralgalaxies in the Ohio State University Bright Galaxy Survey. We comparethe results of these methods with data from the literature, and find ingeneral good agreement. We provide a homogeneous set of mean orientationparameters which can be used to approximately deproject the disks of thegalaxies and facilitate a number of statistical studies of galaxyproperties.Table 1 is only available in electronic form at the CDS via anonymousftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/421/595
| Classifications of the Host Galaxies of Supernovae, Set II
Classifications on the DDO system are given for an additional 231 hostgalaxies of supernovae that have been discovered during the course ofthe Lick Observatory Supernova Search with the Katzman Automatic ImagingTelescope (KAIT). This brings the total number of hosts of supernovae(SNe) discovered (or independently rediscovered) by KAIT, which have sofar been classified on a homogeneous system, to 408. The probabilitythat SNe Ia and SNe II have a different distribution of host-galaxyHubble types is found to be 99.7%. A significant difference is alsofound between the distributions of the host galaxies of SNe Ia and ofSNe Ibc (defined here to include SNe Ib, Ib/c, and Ic). However, nosignificant difference is detected between the frequency distributionsof the host galaxies of SNe II and SNe IIn. This suggests that SNe IInare generally not SNe Ia embedded in circumstellar material that aremasquerading as SNe II. Furthermore, no significant difference is foundbetween the distribution of the Hubble types of the hosts of SNe Ibc andof SNe II. Additionally, SNe II-P and SNe II-L are found to occur amongsimilar stellar populations. The ratio of the number of SNe Ia-pec tonormal SNe Ia appears to be higher in early-type galaxies than it is ingalaxies of later morphological types. This suggests that the ancestorsof SNe Ia-pec may differ systematically in age or composition from theprogenitors of normal SNe Ia. Unexpectedly, five SNe of Types Ib/c, II,and IIn (all of which are thought to have massive progenitors) are foundin host galaxies that are nominally classified as types E and S0.However, in each case the galaxy classification is uncertain, or newlyinspected images show evidence suggesting a later classification. Amongthese five objects, NGC 3720, the host galaxy of SN 2002at, wasapparently misidentified in the Carnegie Atlas of Galaxies.
| A new catalogue of ISM content of normal galaxies
We have compiled a catalogue of the gas content for a sample of 1916galaxies, considered to be a fair representation of ``normality''. Thedefinition of a ``normal'' galaxy adopted in this work implies that wehave purposely excluded from the catalogue galaxies having distortedmorphology (such as interaction bridges, tails or lopsidedness) and/orany signature of peculiar kinematics (such as polar rings,counterrotating disks or other decoupled components). In contrast, wehave included systems hosting active galactic nuclei (AGN) in thecatalogue. This catalogue revises previous compendia on the ISM contentof galaxies published by \citet{bregman} and \citet{casoli}, andcompiles data available in the literature from several small samples ofgalaxies. Masses for warm dust, atomic and molecular gas, as well asX-ray luminosities have been converted to a uniform distance scale takenfrom the Catalogue of Principal Galaxies (PGC). We have used twodifferent normalization factors to explore the variation of the gascontent along the Hubble sequence: the blue luminosity (LB)and the square of linear diameter (D225). Ourcatalogue significantly improves the statistics of previous referencecatalogues and can be used in future studies to define a template ISMcontent for ``normal'' galaxies along the Hubble sequence. The cataloguecan be accessed on-line and is also available at the Centre desDonnées Stellaires (CDS).The catalogue is available in electronic form athttp://dipastro.pd.astro.it/galletta/ismcat and at the CDS via anonymousftp to\ cdsarc.u-strasbg.fr (130.79.128.5) or via\http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/405/5
| Supernovae 2002hb, 2002hc, 2002hd
IAUC 7999 available at Central Bureau for Astronomical Telegrams.
| Local velocity field from sosie galaxies. I. The Peebles' model
Pratton et al. (1997) showed that the velocity field around clusterscould generate an apparent distortion that appears as tangentialstructures or radial filaments. In the present paper we determine theparameters of the Peebles' model (1976) describing infall of galaxiesonto clusters with the aim of testing quantitatively the amplitude ofthis distortion. The distances are determined from the concept of sosiegalaxies (Paturel 1984) using 21 calibrators for which the distanceswere recently calculated from two independent Cepheid calibrations. Weuse both B and I-band magnitudes. The Spaenhauer diagram method is usedto correct for the Malmquist bias. We give the equations for theconstruction of this diagram. We analyze the apparent Hubble constant indifferent regions around Virgo and obtain simultaneously the Local Groupinfall and the unperturbed Hubble constant. We found:[VLG-infall = 208 ± 9 km s-1] [\log H =1.82 ± 0.04 (H ≈ 66 ± 6 km s-1Mpc-1).] The front side and backside infalls can be seenaround Virgo and Fornax. In the direction of Virgo the comparison ismade with the Peebles' model. We obtain: [vinfall} =CVirgo/r0.9 ± 0.2] withCVirgo=2800 for Virgo and CFornax=1350 for Fornax,with the adopted units (km s-1 and Mpc). We obtain thefollowing mean distance moduli: [μVirgo=31.3 ± 0.2(r=18 Mpc )] [μFornax=31.7 ± 0.3 (r=22 Mpc). ] Allthese quantities form an accurate and coherent system. Full Table 2 isonly available in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/393/57
| H I-bright Galaxies in the Southern Zone of Avoidance
A blind survey for H I-bright galaxies in the southern zone of avoidance(212deg<=l<=36deg, |b|<=5deg)has been made with the 21 cm multibeam receiver on the Parkes 64 m radiotelescope. The survey, sensitive to normal spiral galaxies to a distanceof ~40 Mpc and more nearby dwarfs, detected 110 galaxies. Of these, 67have no counterparts cataloged in the NASA/IPAC Extragalactic Database.In general, the uncataloged galaxies lie behind thicker obscuration thando the cataloged objects. All the newly discovered galaxies have H Iflux integrals that are more than an order of magnitude lower than thoseof the Circinus galaxy. The survey recovers the Puppis Cluster andforeground group, and the Local Void remains empty. The H I massfunction derived for the sample is satisfactorily fitted by a Schechterfunction with parameters α=1.51+/-0.12,Φ*=0.006+/-0.003, and logM*=9.7+/-0.10.
| G247.8+4.9: A Newly Discovered Optical Supernova Remnant in Puppis
As a first step to investigate a newly detected possible supernovaremnant in Puppis, a few optical spectra have been obtained. The spectraof this extremely faint nebula, although of poor quality, show strong [Nii] 6583/6548 Å emission. Radial velocities derived from the [Nii] 6583 Å line amount to 50 km s^-1, for both the easternmost andwesternmost optical borders of the nebula, and a distinctly blueshiftedvelocity relative to this value for an emission region close to theeastern rim. In order to check whether the remnant might be akin to thenebula W50 associated with the compact source SS 433, a spectrum of fourstars near the center of the image of the nebula was taken; it showedthem to be of quite ordinary type and exhibits some traces of (nebular)[N ii] 6583 Å emission. No IRAS source is located at or within theboundaries of the nebula, which coincides with an extended radio sourceof about 78 mJy at 4850 MHz. The star that gave rise to the remnant mayhave been a remote member of the Pup OB2 association, at a distance ofabout 5 kpc.
| 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 hydrogen in the central regions of southern infrared galaxies
An extensive set of molecular hydrogen observations of centers ofsouthern infrared galaxies is presented. Our data are combined withpublished infrared and radio observations to investigate therelationship between nuclear and circumnuclear activity. We convert theobservational data to absolute luminosities, by applying the knowndistances. The resulting dataset covers several decades in luminosityfor the various parameters, which observe fairly tight correlations. Theparameters of our (power law) fits are, at the level of accuracyachieved, not dependent on the type of nuclear activity: while thedataset comprises a mixture of alleged Seyfert, Liner & starburstgalaxies, single fits match the complete sample well enough. Inparticular, non-thermal nuclei (AGN) present in some of the galaxies inthe current sample, do not stand out in the parameters we investigated.The absence of a significant dependence on the nuclear type isconsistent with the idea that the ever present starbursts energeticallydominate a possible `AGN in a dusty environment'-component in mostgalaxy nuclei with infrared excesses. The size of the H_2 emittingregion is found to be proportional to the square root of the 21 cm radiocontinuum luminosity. The excitation of the circumnuclear H_2 isdominated by shocks. If the H_2 extent marks the size of an inner cavityin the dense molecular material surrounding a galaxy nucleus and theradio luminosity is proportional to the mechanical luminosity of(circum)nuclear winds. This result then indicates that the cavity sizeoccurs at constant pressure in the sample galaxies, in accordance withthe superwind model by Heckman et al. (1990) [ApJS, 74, 833]. Ourresults, together with those obtained by others, thus suggest thatluminosities and size scales of excited gas associated with activenuclei are dominated by the mechanical energy input. Given thedifficulties of uniquely establishing the presence of an AGN, we cannotexclude that (a large fraction of the) infrared luminous galaxiesprocure part of their radiated energy through accretion onto a massivedark object.
| Redshift Distribution of Galaxies in the Southern Milky Way Region 210 degrees < L < 360 degrees and B < 15 degrees
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996ApJS..107..521V&db_key=AST
| A CO survey of galaxies with the SEST and the 20-m Onsala telescope.
A large survey of galaxies in the J=1-0 CO line, performed during1985-1988 using the 15-m SEST and the 20-m millimetre wave telescope ofOnsala Space Observatory, is presented. The HPBW of the telescopes are44" and 33" at 115GHz, respectively. The central positions of 168galaxies were observed and 101 of these were detected in the CO line.More than 20% of these are new detections. Maps of some of the galaxiesare also presented.
| The FCRAO Extragalactic CO Survey. I. The Data
Emission from the CO molecule at λ = 2.6 mm has been observed at1412 positions in 300 galaxies using the 14 m telescope of the FiveCollege Radio Astronomy Observatory (HPBW = 45"); these data comprisethe FCRAO Extragalactic CO Survey. In this paper we describe the galaxysample, present the data, and determine global CO fluxes and radialdistributions for the galaxies in the Survey. Future papers will dealwith the data analysis, both with regard to the global properties ofgalaxies and the radial distributions within them. CO emission wasdetected in 236 of the 300 Survey galaxies for an overall detection rateof 79%; among the 52 Sc galaxies in the Survey, the detection rate wasas high as 96%. most of the 193 galaxies observed in multiple positionsexhibit CO distributions which peak at the center. However, a smallnumber (10-primarily Sb galaxies) exhibit CO rings at 45" resolution,and a similar number (18-primarily Sc galaxies) have CO distributionswhich peak on one side of the center. We derive CO isophotal diametersfor 151 galaxies and find the mean ratio of CO to optical isophotaldiameters to be 0.5. We also find a trend along the Hubble sequence suchthat the mean ratio of CO to optical isophotal diameters is smallestamong the early-type spirals (SO/a, Sa, and Sab) and the mean ratioincreases for Sb, Sbc, and Sc galaxies, finally decreasing among thelater types. Comparison of the global fluxes we derive for the Surveygalaxies with independent measurements from the literature indicatesthat the global fluxes we derive are accurate to ~40%.
| Penetrating the "zone of avoidance". I. A compilation of optically identified extragalactic objects within |b|<=5deg.
As an introduction to a series of papers on galaxies identified in the"zone of avoidance" (ZOA) of the Milky Way we present a compilation ofhopefully all published galaxies and quasars that were ever opticallyidentified within |b|<=5deg. We present 2304 objects and list (anddiscuss), in addition to their (often considerably improved)coordinates, the best available morphological type, optical maximumdiameters in the red, up-to-date heliocentric radial velocities,reference to the papers where a specific object was first opticallyidentified, and results of cross-checks with the IRAS point sourcecatalogue. This compilation may serve as a presentation of the "state ofaffairs" in optical identifications of extragalactic objects behind theplane of the Galaxy, up to end 1993.
| Radial Velocity Distribution of the Galaxies in the Puppis Hidden Concentration Behind the Milky-Way
We investigate the radial velocity distribution of the galaxies in thePuppis region behind the Milky Way around (l,b)~(245^deg^, 0^deg^),where a concentration of galaxies was recently recognized through thesystematic search for galaxies behind the zone of avoidance. Using thelower limit sample of the 6O-micron flux-limited sample of IRAS galaxiesbrighter than f_60_ = 0.6 Jy, we find a large nearby clustering ofgalaxies at about 20 h^-1^ Mpc, whose peak spatial density at 7.5h^-1^Mpc scale is at least twice the whole-sky average. This Puppisconcentration is probably associated with the S1 supercluster at (l,b) =(220^deg^, - 15^deg^) detected in the QDOT survey, and this associationis likely to be comparable to other nearby superclusters such as theVirgo, the Hydra, the Centaurus and the Fornax-Eridanus superclusters.Consequently, the effect of the Puppis concentration on the peculiarmotions of the Local Group and other nearby galaxies should beconsiderable. There is no prominent individual cluster in the Puppisregion, however, although some galaxies are concentrated into theregions around (l,b) = (245^deg^, - 7^deg^) and (237^deg^, - 15^deg^);the richness of these individual clusters in IRAS galaxies is as largeas that of the Fornax cluster, and perhaps half or more of that of theVirgo cluster. We also study the radial velocity distribution of thegalaxies selected by an optical limiting diameter, although uncertaintyin the selection is large because of galactic extinction. Thedistribution of these diameter-selected galaxies shows good agreementwith that of the IRAS-selected ones.
| A search for IRAS galaxies behind the southern Milky Way
We systematically searched for IRAS galaxies with 60 micrometer fluxdensity larger than 0.6 Jy by using the UK Schmidt Infrared and IIIa-JAtlases in the Milky Way region (absolute value of b less than 15 deg)between l = 210 deg and 360 deg. We first selected about 4000 IRAS pointsources by using our far-infrared criteria, which are optimized for thesearch of IRAS galaxies behind the Milky Way region, and then inspectedvisually the optical counterparts of them on the Schmidt Atlas filmcopies. We found 966 IRAS sources associated with galaxy-like objects.The list of the objects is presented here with the IRAS source name,Galactic coordinates, IRAS flux densities, field number and emulsion ofthe Atlas, type and size of galaxy (-like) image, redshift,multiplicity, and cross-identification. Of these, 423 galaxies arealready cataloged in the Catalog of Galaxies and Quasars Observed in theIRAS Survey, and most of the remaining 543 galaxy candidates are newlyidentified in this search. Although the radial velocities are known foronly 387 galaxies, of which 60 were newly measured by us so far, weinferred the contamination by Galactic objects to be small from the goodcorrelation between the sky distributions of the newly identified galaxycandidates and the previously cataloged galaxies. In the regions wherethe Galactic molecular clouds dominate, almost all the sources were notidentified as galaxies. The detected galaxies are clustered in the threeregions around l = 240 deg, 280 deg, and 315 deg, where the projectednumber densities are higher than the whole-sky average of IRAS galaxiesof the same flux limit.
| IRAS LRS spectroscopy of galaxies
The study presents IRAS LRS data for 350 galaxies with pointlike IRASsources having either S(12) or S(25) not less than 1.5 Jy. Techniquesare presented which form the mean of an ensemble of LRS spectra, ll ofwhich are only of low signal-to-noise ratio, by quantitative evaluationof the significance of the individual spectra for each object ratherthan mere acceptance of the 'average spectrum' present in the completeLRS data base. Average LRS spectra for groups of galaxies with distinctoptical nuclear properties are formed. Average LRS spectra for severalcategories of objects are presented and interpreted. H II regiongalaxies show the polycyclic aromatic hydrocarbon spectrum of bands inemissions; type 2 Seyferts present a broad emission feature parking near16 microns; LINERs and galaxies without optical emission lines have LRSspectra that decline with wavelength, whereas type 1 Seyferts and WRgalaxies have red spectra suggestive of nonthermal emission processes.
| Groups of galaxies within 80 Mpc. II - The catalogue of groups and group members
This paper gives a catalog of the groups and associations obtained bymeans of a revised hierarchical algorithm applied to a sample of 4143galaxies with diameters larger than 100 arcsec and redshifts smallerthan 6000 km/s. The 264 groups of galaxies obtained in this way (andwhich contain at least three sample galaxies) are listed, with the looseassociations surrounding them and the individual members of eachaggregate as well; moreover, the location of every entity among 13regions corresponding roughly to superclusters is specified. Finally,1729 galaxies belong to the groups, and 466 to the associations, i.e.,the total fraction of galaxies within the various aggregates amounts to53 percent.
| H I-observations of galaxies in the zone of avoidance in Puppis
Observations of 76 apparently faint galaxies in the galactic plane inPuppis with the 100-m radio telescope in Effelsberg are reported. Roughcorrections of the magnitudes for extinction show that most of thegalaxies are actually quite bright. These are concentrated into fourgroups. These newly identified nearby groups and filaments mightcontribute to the peculiar motion of the Local Group. A more distantfilament at 5000 km/s is indicated in the distribution as well and seemsconnected to outlying extragalactic large-scale structures. The globalproperties of the observed galaxies such as total mass, H I-mass andMHI/LB are normal in every respect and reflect the properties of atypical nearby sample of galaxies. The IR properties of the 34 galaxieslisted in the IRAS PSC such as the f100/f60 color temperature and theratio of the blue to IR flux are found to be representative of anoptically selected galaxy sample, and the IR luminosity to correlatewith the H-I mass.
| Groups of galaxies within 80 Mpc. I - Grouping hierarchical method and statistical properties
An all-sky sample of 4143 galaxies comprising all the objects with anapparent diameter D(25) larger than 100 arcsec and with recessionvelocities smaller than 6000 km/s (i.e., closer than 80 Mpc) wasanalyzed using a hierarchical algorithm similar to Tully's (1987)algorithm, in order to classify the galaxies into groups defined asentities having an average luminosity density higher than 8 x 10 exp 9solar luminosity in the B band/Mpc cubed. The hierarchy is built on themass density of the aggregates progressively formed by the method,corrected for the loss of faint galaxies with the distance. In this way,264 groups of at least three members were identified, among which 82have more than five members and are located at distances lower than 40Mpc. It was found that (1) almost all the crossing times are lower thanH0 exp -1, confirming the bound nature of the groups; (2) themedian virial mass to blue luminosity ratio of the groups is 74 solarmass per solar luminosity in the B band; and (3) the M/L ratio increaseswith the group size, indicating the presence of dark matter aroundgalaxies to a distance of 500 kpc.
| IRAS sources beyond the solar circle. I - CO observations
C-12O (J = 1-0) has been observed with the 15-m SEST and the 30-m IRAMtelescope in the direction of 1302 IRAS sources with colors of starforming regions located within 10 deg of the galactic plane in theinterval between 85 and 280 deg. Emission components with line profilesthat are non-Gaussian (showing, e.g., possible self-absorption or wings)are identified; this information may serve as a basis for selectingsources for future research. For all components, kinematic heliocentricand galactocentric distances, and distances from the galactic plane arederived. For those components which may be associated with the IRASsources, bolometric luminosities are derived. These data will beanalyzed and compared with HI data in subsequent papers.
| The peculiar velocity of the Local Group. I - H I observations of SB and SBC galaxies
H I observations of a sample of 128 Sb and Sbc galaxies ranging inlinear diameter from 9-128 kpc, and in total mass from 6.3 x 10 to the9th solar masses to 1.3 x 10 to the 12th solar masses, are presented.Measurements of H I self-absorption are not found to vary withinclination, though a dependence of observed diameters and luminositieson inclination is noted. Total surface mass density and color index areshown to be highly correlated, implying that star-formation in thesegalaxies is governed by disk density rather than total mass or gasrichness. From 12-arcmin resolution local Galactic H I observations, newcorrection factors for diameters and luminosities are derived to allowfor the effects of galactic obscuration.
| H2O and OH maser emission from bright IRAS galaxies
IC10's H2O maser emission, with its isotropic luminosity of 1 solarluminosity, is the most powerful detected to date in a compact irregulargalaxy. The main velocity component is highly variable, and mightrepresent a flare more intense than that found in Orion; CO is alsodetected at -330 km/sec. The molecular mass within the beam isdetermined and compared with estimates of the H I mass and the totalmass of IC10. A systematic investigation is conducted on the basis ofH2O data from a sample of 43 luminous IRAS galaxies, and correlationsare found between the presence of strong H2O or OH masers and the60/100-micron and 12/25-micron color temperatures. An anticorrelation isnoted between the 25/60 and 60/100-micron vs. 12/25-micron colortemperatures in the sample of bright extragalactic IRAS sources.
| Southern Galaxy Catalogue.
Not Available
| The nuclear activity of interacting galaxies
A search for active galactic nuclei among interacting galaxies isreported. A sample of 167 systems of interacting and asymmetric galaxieswas observed spectrophotometrically in the spectral range 4700-7100 A.The results are compared with a sample of isolated galaxies. It is foundthat (1) there are no Seyfert nuclei in elliptical or dwarf irregulargalaxies of the sample; (2) there is an excess of Seyfert nuclei amonginteracting spirals, but it is only at the 90 percent confidence level;(3) this excess becomes statistically significant (98 percent) when onlystrongly interacting spirals are included (four new Seyfert nuclei arepresented); (4) in the subgroup of galaxies with extreme tidaldistortions, no Seyfert nuclei were found.
| Atlas of interacting galaxies, Part. II and the concept of fragmentation of galaxies.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977A&AS...28....1V&db_key=AST
| A catalogue of galaxies near the galactic plane between l=245 and l=255.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976A&AS...25..519D&db_key=AST
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