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|The ISOPHOT 170 μm Serendipity Survey II. The catalog of optically identified galaxies%|
The ISOPHOT Serendipity Sky Survey strip-scanning measurements covering≈15% of the far-infrared (FIR) sky at 170 μm were searched forcompact sources associated with optically identified galaxies. CompactSerendipity Survey sources with a high signal-to-noise ratio in at leasttwo ISOPHOT C200 detector pixels were selected that have a positionalassociation with a galaxy identification in the NED and/or Simbaddatabases and a galaxy counterpart visible on the Digitized Sky Surveyplates. A catalog with 170 μm fluxes for more than 1900 galaxies hasbeen established, 200 of which were measured several times. The faintest170 μm fluxes reach values just below 0.5 Jy, while the brightest,already somewhat extended galaxies have fluxes up to ≈600 Jy. For thevast majority of listed galaxies, the 170 μm fluxes were measured forthe first time. While most of the galaxies are spirals, about 70 of thesources are classified as ellipticals or lenticulars. This is the onlycurrently available large-scale galaxy catalog containing a sufficientnumber of sources with 170 μm fluxes to allow further statisticalstudies of various FIR properties.Based on observations with ISO, an ESA project with instruments fundedby ESA Member States (especially the PI countries: France, Germany, TheNetherlands and the UK) and with the participation of ISAS and NASA.Members of the Consortium on the ISOPHOT Serendipity Survey (CISS) areMPIA Heidelberg, ESA ISO SOC Villafranca, AIP Potsdam, IPAC Pasadena,Imperial College London.Full Table 4 and Table 6 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (22.214.171.124) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/422/39
|Supernova 2003gh in NGC 2466|
IAUC 8159 available at Central Bureau for Astronomical Telegrams.
|A Catalog of H I-Selected Galaxies from the South Celestial Cap Region of Sky|
The first deep catalog of the H I Parkes All Sky Survey (HIPASS) ispresented, covering the south celestial cap (SCC) region. The SCC areais ~2400 deg2 and covers δ<-62°. The average rmsnoise for the survey is 13 mJy beam-1. Five hundredthirty-six galaxies have been cataloged according to their neutralhydrogen content, including 114 galaxies that have no previous catalogedoptical counterpart. This is the largest sample of galaxies from a blindH I survey to date. Most galaxies in optically unobscured regions of skyhave a visible optical counterpart; however, there is a small populationof low-velocity H I clouds without visible optical counterparts whoseorigins and significance are unclear. The rms accuracy of the HIPASSpositions is found to be 1.9′. The H I mass range of galaxiesdetected is from ~106 to ~1011 Msolar.There are a large number of late-type spiral galaxies in the SCC sample(66%), compared with 30% for optically selected galaxies from the sameregion in the NASA Extragalactic Database. The average ratio of H I massto B luminosity of the sample increases according to optical type, from1.8 Msolar/Lsolar for early types to 3.2Msolar/Lsolar for late-type galaxies. The HI-detected galaxies tend to follow the large-scale structure traced bygalaxies found in optical surveys. From the number of galaxies detectedin this region of sky, we predict the full HIPASS catalog will contain~5000 galaxies, to a peak flux density limit of ~39 mJy (3 σ),although this may be a conservative estimate as two large voids arepresent in the region. The H I mass function for this catalog ispresented in a subsequent paper.
|RR Lyrae stars in the Sagittarius dwarf galaxy: Period analysis|
We carried out a period analysis on ~ 3700 RR Lyrae stars on two Schmidtfields centred on (l,b)=(3.1deg, -7.1deg) and(6.6deg, -10.8deg) respectively, covering an areaof ~ 50 deg2. These stars are distributed almost evenlybetween the Sagittarius dwarf galaxy (Sgr) and the Milky Way. For Sgrmembers, the average periods are =0.574d and =0.322d for RRab and RRc stars respectively.This places Sgr in the long-period tail of the Oosterhoff I group. Wereport the detection of 53 double-mode RR Lyrae stars (RRd) within oursample. The magnitude of 40 of these stars is consistent with membershipin Sgr whereas 13 RRds are located within our Galaxy. We also found 13RR Lyraes (5 in Sgr and 8 in the Galaxy) exhibiting two closely spacedfrequencies, most probably related to non-radial pulsations. The perioddistribution of the RR Lyrae variables in Sgr is compared to those ofother Milky Way satellites. We find a remarkable similarity between theRR Lyrae populations in Sgr and the Large Magellanic Cloud (LMC),suggesting that these galaxies have similar horizontal branchmorphologies. This may indicate that Sgr and the LMC started theirformation under similar conditions. Using various photometricindicators, we estimate the metallicity of the RR Lyrae stars in Sgr andfind < [Fe/H]> =~ -1.6 dex with a dispersion of ~ +/-0.5 dexaround this value and a minor but significant population at ≲-2.0dex. We do not find evidence for a spatial metallicity gradient in theRR Lyrae population of Sgr. From the spatial distribution of RR Lyraes,we find that the main body of Sgr contains ~ 4200 RRab stars. Assumingthat population gradients are negligible in Sgr, we findMV(Sgr) =~ -13.9+0.4-0.6 mag for themain body. If Sgr has been stripped of 50% of its mass through Galactictides, as assumed by some models, it would imply a total absolutemagnitude of ~ -14.7 mag for this galaxy. Such a luminosity would beconsistent with the empirical metallicity/luminosity relation for dwarfspheroidal galaxies. Table 15 is only available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (126.96.36.199) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/375/909. Based onobservations obtained at the European Southern Observatory, La Silla,Chile.
|The ISOPHOT 170 μ m serendipity survey. I. Compact sources with galaxy associations|
The first set of compact sources observed in the ISOPHOT 170 μmSerendipity Survey is presented. From the slew data with low(I100 μm <= 15 MJy/sr) cirrus background, 115well-observed sources with a high signal-to-noise ratio in all detectorpixels having a galaxy association were extracted. Of the galaxies withknown optical morphologies, the vast majority are classified as spirals,barred spirals, or irregulars. The 170 μm fluxes measured from theSerendipity slews have been put on an absolute flux level by usingcalibration sources observed additionally with the photometric mappingmode of ISOPHOT. For all but a few galaxies, the 170 μm fluxes aredetermined for the first time, which represents a significant increasein the number of galaxies with measured Far-Infrared (FIR) fluxes beyondthe IRAS 100 μm limit. The 170 μm fluxes cover the range 2 <~F170 μm la 100 Jy. Formulae for the integrated FIR fluxesF40-220μm and the total infrared fluxesF1-1000μm incorporating the new 170 μm fluxes areprovided. The large fraction of sources with a high F170μm / F100 μm flux ratio indicates that a cold(TDust la 20 K) dust component is present in many galaxies.The detection of such a cold dust component is crucial for thedetermination of the total dust mass in galaxies, and, in cases with alarge F170 μm / F100 μm flux ratio,increases the dust mass by a significant factor. The typical mass of thecoldest dust component is MDust = 107.5 +/- 0.5Msun , a factor 2-10 larger than that derived from IRASfluxes alone. As a consequence, the majority of the derived gas-to-dustratios are much closer to the canonical value of ~ 160 for the MilkyWay. By relaxing the selection criteria, it is expected that theSerendipity Survey will eventually lead to a catalog of 170 μm fluxesfor ~ 1000 galaxies. Based on observations with ISO, an ESA project withinstruments funded by ESA Member States (especially the PI countries:France, Germany, the Netherlands and the United Kingdom) and with theparticipation of ISAS and NASA. Members of the Consortium on the ISOPHOTSerendipity Survey (CISS) are MPIA Heidelberg, ESA ISO SOC Villafranca,AIP Potsdam, IPAC Pasadena, Imperial College London.
|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.
|Lopsided Spiral Galaxies and a Limit on the Galaxy Accretion Rate|
We present a measurement of lopsidedness for the stellar disks of 60field spiral galaxies in terms of the azimuthal m = 1 Fourier amplitude,A1, of the stellar light. We confirm the previous result (Rix &Zaritsky) that ~30% of field spiral galaxies in a magnitude-limitedsample exhibit significant lopsidedness ( >= 0.2) atlarge radii (R > 1.5 disk scalelengths). We conjecture that thislopsidedness is caused by tidal interactions and calculate an upperlimit on the accretion rate of small galaxies. We exploit thecorrelation between lopsidedness and photometric measures of recent starformation (Zaritsky) to obtain two independent estimates of the lifetimeof these m = 1 distortions. First, we show that lopsided galaxies havean excess of blue luminosity relative to that of symmetric galaxies withthe same H I linewidth, which we attribute to a recent star formationepisode that was triggered by an interaction between the galaxy and acompanion. We use stellar population models (Bruzual & Charlot) toestimate the time since that interaction. Second, we use the N-bodysimulation of an infalling satellite by Walker, Mihos, & Hernquistto estimate how fast tidally induced m = 1 distortions are erasedthrough phase mixing. Both approaches indicate that the observations areconsistent with a hypothesized tidal interaction that occurred about 1Gyr ago for galaxies that are lopsided at the 20% level. By combiningthis lifetime estimate for lopsidedness, the observed frequency of suchdistortions, and a correction to the survey volume that depends on theincrease in luminosity during an interaction, we derive an upper limiton the current companion accretion rate of field spiral galaxies (forcompanion masses ~10% parent galaxy mass) that lies in the range0.07--0.25 Gyr-1. The principal uncertainty in this limit arises fromambiguities in the interpretation of the correlation betweenlopsidedness and MB.
|Nonaxisymmetric Structures in the Stellar Disks of Galaxies|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995ApJ...447...82R&db_key=AST
|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.
|Late-type galaxies - The shapes of the spiral arm filaments|
A study is conducted of the shapes of spiral arm filaments in 18late-type galaxies in order to test the SSPSF theory's hyperbolic spiralarm predictions. After subtracting the disk component from theluminosity distribution by image filtering, the directions along whichthe intensity variations of the extreme Population I are minimal weredetermined in circular zones around the centers of the deprojectedimages; this constitutes an objective determination of pitch angles evenfor galaxies with very short and filamentary arms. The results obtainedseverely contradict SSPSF theory, instead implying that the spiral armsare wave phenomena exhibiting logarithmic shapes.
|BV photometry and radial velocities of southern spiral galaxies|
Multiaperture photoelectric photometry for 119 southern spiral galaxiesand heliocentric velocities for 98 southern spiral galaxies obtainedfrom image-tube spectrograms are presented. The data were collected in1976, 1977, and 1978 at Cerro Tololo Inter-American Observatory. Themagnitude and (B-V) color index are compared with aperture diameter inorder to determine if the present data correlate with previousmeasurements. The comparison reveals that the data correspond. Theinternal measurement error of the radial velocities is estimated; it isobserved that the internal error for one measurement is 41 km/sec.
|Latel-type galaxies - Star formation rates|
A simple method for determining star formation rates (SFRs) in externalgalaxies is presented which is based on surface photometry in one coloronly. The intensity distributions of 59 late-type spiral and irregulargalaxies were divided into two components each, one containing the lightof the smoothly distributed old disk population, the other containingthe light of the clumped extreme Population I. This makes it possible todetermine the ratios of the 'present' SFRs (for stars with ages lessthan 50 million yr) to the average SFRs. Among other results, this ratiois found to be higher in asymmetric galaxies than in symmetric ones.
|Southern Galaxy Catalogue.|
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