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Публикации по объекту
Late-Time Radio Observations of 68 Type Ibc Supernovae: Strong Constraints on Off-Axis Gamma-Ray Bursts
We present late-time radio observations of 68 local Type Ibc supernovae,including six events with broad optical absorption lines(``hypernovae''). None of these objects exhibit radio emissionattributable to off-axis gamma-ray burst jets spreading into our line ofsight. Comparison with our afterglow models reveals the followingconclusions. (1) Less than ~10% of Type Ibc supernovae are associatedwith typical gamma-ray bursts initially directed away from our line ofsight; this places an empirical constraint on the GRB beaming factor of<~104, corresponding toan average jet opening angle, θj>~0.8d. (2) Thisholds in particular for the broad-lined supernovae (SNe 1997dq, 1997ef,1998ey, 2002ap, 2002bl, and 2003jd), which have been argued to host GRBjets. Our observations reveal no evidence for typical (or evensubenergetic) GRBs and rule out the scenario in which every broad-linedSN harbors a GRB at the 84% confidence level. Their large photosphericvelocities and asymmetric ejecta (inferred from spectropolarimetry andnebular spectroscopy) appear to be characteristic of the nonrelativisticSN explosion and do not necessarily imply the existence of associatedGRB jets.
| 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
| Supernova 2001ef in IC 381
IAUC 7710 available at Central Bureau for Astronomical Telegrams.
| 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.
| On the Nature of the FBS Blue Stellar Objects and the Completeness of the Bright Quasar Survey
Not Available
| 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.
| A catalogue of spatially resolved kinematics of galaxies: Bibliography
We present a catalogue of galaxies for which spatially resolved data ontheir internal kinematics have been published; there is no a priorirestriction regarding their morphological type. The catalogue lists thereferences to the articles where the data are published, as well as acoded description of these data: observed emission or absorption lines,velocity or velocity dispersion, radial profile or 2D field, positionangle. Tables 1, 2, and 3 are proposed in electronic form only, and areavailable from the CDS, via anonymous ftp to cdsarc.u-strasbg.fr (to130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html
| Short 21-cm WSRT observations of spiral and irregular galaxies. HI properties.
We present the analysis of neutral hydrogen properties of 108 galaxies,based on short 21-cm observations with the Westerbork Synthesis RadioTelescope (WSRT). The results of two HI surveys are analysed toinvestigate the existence of relations between optical and HIproperties, like diameters, hydrogen masses and average surfacedensities. For all galaxies in our sample we find that the HI diameter,defined at a surface density level of 1Msun_/pc^2^, is largerthan the optical diameter, defined at the 25^th^mag/arcsec^2^ isophotallevel. The Hi-to-optical-diameter ratio does not depend on morphologicaltype or luminosity. The strongest, physically meaningful, correlationfor the sample of 108 galaxies is the one between logM_HI_ and logD_HI_,with a slope of 2. This implies that the HI surface density averagedover the whole HI disc is constant from galaxy to galaxy, independent ofluminosity or type. The radial HI surface density profiles are studiedusing the technique of principal component analysis. We find that about81% of the variation in the density profiles of galaxies can beexplained by two dimensions. The most dominant component can be relatedto "scale" and the second principal component accounts for the variancein the behaviour of the radial profile in the central parts of galaxies(i.e. "peak or depression") . The third component accounts for 7% of thevariation and is most likely responsible for bumps and wiggles in theobserved density profiles.
| Short WSRT HI observations of spiral galaxies.
We have obtained short HI observations of 60 late type spiral galaxieswith the Westerbork Synthesis Radio Telescope (WSRT). Several HIproperties are presented, including the radial surface densitydistribution of HI and a position-velocity map. When possible these arecompared to those measured from single-dish observations. We confirmearlier results that there is no serious systematic difference betweenthe WSRT and single-dish observations in total flux and linewidths.
| Recalibration of the H-0.5 magnitudes of spiral galaxies
The H-magnitude aperture data published by the Aaronson et al.collaboration over a 10 year period is collected into a homogeneous dataset of 1731 observations of 665 galaxies. Ninety-six percent of thesegalaxies have isophotal diameters and axial ratios determined by theThird Reference Cataloque of Bright Galaxies (RC3; de Vaucouleurs et al.1991), the most self-consistent set of optical data currently available.The precepts governing the optical data in the RC3 are systematicallydifferent from those of the Second Reference Catalogue (de Vaucouleurs,de Vaucouleurs, & Corwin 1976), which were used by Aaronson et al.for their original analyses of galaxy peculiar motions. This in turnleads to systematic differences in growth curves and fiducialH-magnitudes, prompting the present recalibration of the near-infraredTully-Fisher relationship. New optically normalized H-magnitude growthcurves are defined for galaxies of types SO to Im, from which new valuesof fiducial H-magnitudes, Hg-0.5, are measured forthe 665 galaxies. A series of internal tests show that these fourstandard growth curves are defined to an accuracy of 0.05 mag over theinterval -1.5 less than or equal to log (A/Dg) less than orequal to -0.2. Comparisons with the Aaronson et al. values of diameters,axial ratios, and fiducial H-magnitudes show the expected differences,given the different definitions of these parameters. The values ofHg-0.5 are assigned quality indices: a qualityvalue of 1 indicates an accuracy of less than 0.2 mag, quality 2indicates an accuracy of 0.2-0.35 mag, and quality 3 indicates anaccuracy of more than 0.35 mag. Revised values of corrected H I velocitywidths are also given, based on the new set of axial ratios defiend bythe RC3.
| The first byurakan Spectral Sky Survey. Blue stellar objects. X. The zone+73°≤σ≤+80°
We present the tenth list of blue stellar objects of the second part ofthe First Byurakan Spectral Sky Survey (FBS). The list contains 100objects in the region+73°+80° and3 h 30 m ≤18 h 30 mencompassing an area of 355 square degrees. The objects have stellar Vmagnitude within the limits 12.0-18.5 and B-V colors between-0.77and+0.37. Of these 100 objects, 80 were discovered for the first time.We give the equatorial coordinates, stellar V magnitude, color index CI,and preliminary classification of the objects on the basis oflow-disperion prismatic spectra. For 29 objects we give approximatetypes, among which 4 are candidates for quasars, 2 for Seyfert galaxies,1 for superassociation galaxy IC 381, 18 for white dwarfs, and 4 forcataclysmic variables.
| Total and effective colors of 501 galaxies in the Cousins VRI photometric system
Total color indices (V-R)T, (V-I)T and effectivecolor indices (V-R)e, (V-I)e in the Cousins VRIphotometric system are presented for 501 mostly normal galaxies. Thecolors are computed using a procedure outlined in the Third ReferenceCatalogue of Bright Galaxies (RC3) whereby standard color curvesapproximated by Laplace-Gauss integrals are fitted to observedphotoelectric multiaperture photometry. 11 sources of such photometrywere used for our analysis, each source being assigned an appropriateweight according to a rigorous analysis of residuals of the data fromthe best-fitting standard color curves. Together with the integrated B-Vand U-B colors provided in RC3, our analysis widens the range ofwavelength of homogeneously defined colors of normal galaxies of allHubble types. We present color-color and color-type relations that canbe modeled to understand the star formation history of galaxies.
| 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.
| Nearby galaxy flows modeled by the light distribution - Distances, model, and the local velocity anomaly
Tables giving measured galaxy distances used to construct a map ofobserved peculiar velocities, and giving a grid of the distribution oflight used to construct a map of expected peculiar velocities arepresented. A preferred model was developed which yielded a best fitbetween these maps, and this model was used to generate output kinematicdistances which are recorded for groups and individual galaxies withV0 of less than 3000 km/s. In terms of the ratio ofpeculiar-to-systemic velocities, the local velocity anomaly is the mostimportant perturbation involving substantial numbers of galaxies forthis case. The ratio of these quantities in this case is larger than forthe more famous cases of the Virgocentric or Great Attractorperturbations. Maps which illustrate the fit of the present mass modelto the velocity data in the local region are provided. A graphicaldemonstration of the relative importance of large-scale streaming tolocal motions within the context of this model is presented.
| Dark matter in spiral galaxies
The Tully-Fisher relation is used to probe dark matter (DM) in theoptical regions of spiral galaxies. By establishing it at severaldifferent isophotal radii in an appropriate sample of 58 galaxies withgood B-band photometry and rotation curves, it is shown that some of itsattributes (such as scatter, residuals, nonlinearity, and bias)dramatically decrease moving from the disk edge inward. This behaviorchallenges any mass model which assumes no DM or aluminosity-independent DM mass fraction interior to the optical radiusof spiral galaxies.
| Uncertainties in 21 centimeter redshifts. I - Data
High-precision data on the 21-cm redshifts, profile widths, and shapesfor 625 galaxies are presented. Each galaxy is listed in across-identification and morphology table. High-resolution spectra arealso given for each galaxy. Internal redshift consistency is roughly 1km/s for galaxies for which the S/N is above 15. No systematic effectshave been found which might influence the observed redshift quantizationat 72.5 km/s or its submultiples.
| 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.
| Arm classifications for spiral galaxies
The spiral arm classes of 762 galaxies are tabulated; 636 galaxies withlow inclinations and radii larger than 1 arcmin were classified on thebasis of their blue images on the Palomar Observatory Sky Survey (POSS),76 SA galaxies in the group catalog of Geller and Huchra were alsoclassified from the POSS, and 253 galaxies in high-resolution atlaseswere classified from their atlas photographs. This spiral armclassification system was previously shown to correlate with thepresence of density waves, and galaxies with such waves were shown tooccur primarily in the densest galactic groups. The present sampleindicates, in addition, that grand design galaxies (i.e., those whichtend to contain prominent density wave modes) are physically larger thanflocculent galaxies (which do not contain such prominent modes) by afactor of about 1.5. A larger group sample confirms the previous resultthat grand design galaxies are preferentially in dense groups.
| Morphology of spiral galaxies. I - General properties
Red Palomar Sky Survey plates are scanned to characterize a completesample of 605 spiral galaxies north of declination -33 deg havinginclination angle less than 56 deg and blue diameter 2-15 arcmin. Theselection of the data and the reduction and parameter-extractionprocedures are explained, and the data and the results of statisticalanalysis are presented in tables and graphs. Findings reported include alow frequency of occurrence for small inclination angles (suggestingdistortion of outer structures), similar distributions of central diskbrightness for types Sa-Sc but not for types Sd-Sm (where mean valuesare smaller), fewer late-type galaxies with large exponential-disk scalelengths, no galaxies with both high central brightness and large scalelength (indicating a limit on angular momentum in galaxy formation), anda correlation between mean surface brightness and absolute magnitude forlater-type galaxies but not for types Sa-Scd.
| H I line studies of galaxies. IV - Distance moduli of 468 disk galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985A&AS...59...43B&db_key=AST
| A catalog of infrared magnitudes and H I velocity widths for nearby galaxies
Integrated infrared (1.6 micron) magnitudes and 21 cm velocity widthsare presented for 308 nearby spiral galaxies. Positions, types,inclinations, diameters, H I velocities and flux density integrals, anddistances are also listed. These data form the basis for a recentanalysis of the velocity field in the Local supercluster.
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