- ID:
- ivo://CDS.VizieR/J/ApJ/709/884
- Title:
- Role of starburst-AGN composites in LIRG mergers
- Short Name:
- J/ApJ/709/884
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the fraction of starbursts, starburst-active galactic nucleus (AGN) composites, Seyferts, and low-ionization narrow emission-line region galaxies (LINERs) as a function of infrared luminosity (LIR) and merger progress for ~500 infrared (IR)-selected galaxies. Using the new optical classifications afforded by the extremely large data set of the Sloan Digital Sky Survey, we find that the fraction of LINERs in IR-selected samples is rare (<5%) compared with other spectral types. The lack of strong IR emission in LINERs is consistent with recent optical studies suggesting that LINERs contain AGN with lower accretion rates than in Seyfert galaxies. Most previously classified IR-luminous LINERs are classified as starburst-AGN composite galaxies in the new scheme. Starburst-AGN composites appear to "bridge" the spectral evolution from starburst to AGN in ULIRGs. The relative strength of the AGN versus starburst activity shows a significant increase at high IR luminosity. In ULIRGs (LIR>10^12^L_{sun}_), starburst-AGN composite galaxies dominate at early-intermediate stages of the merger, and AGN galaxies dominate during the final merger stages.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/378/30
- Title:
- ROSAT-BSC galaxy identifications
- Short Name:
- J/A+A/378/30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In a correlation study of the ROSAT All-Sky Survey Bright Source Catalogue (RASS-BSC, Cat. <XI/10>) with the Catalogue of Principal Galaxies (PGC, Cat. <VII/119>) 904 X-ray sources were found that possess possible extragalactic counterparts within a search radius of 100". File table1 contains 1124 optical galaxy entries and 904 relevant X-ray candidates/counterparts from the ROSAT All-Sky Survey. Besides a compilation of X-ray and optical parameters for each source, also the results of an identification screening are given. 547 optical/X-ray correlations have been quoted as reliable identifications. The 904 optical images with X-ray overlay contours (xID_nnn.ps.gz) used in the screening process are added for each user's own judgement.
- ID:
- ivo://CDS.VizieR/J/A+A/329/482
- Title:
- ROSAT Deep Survey in the Lockman Hole
- Short Name:
- J/A+A/329/482
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ROSAT Deep Survey in the Lockman Hole is the most sensitive X-ray survey performed to date, encompassing an exposure time of 207ksec with the PSPC and a total of 1.32Msec with the HRI aboard ROSAT. Here we present the complete catalogue of 50 X-ray sources with PSPC fluxes (0.5-2 keV) above 5.5x10^-15^erg/cm^2^/s.
- ID:
- ivo://CDS.VizieR/J/ApJ/519/533
- Title:
- ROSAT observations of ACO clusters
- Short Name:
- J/ApJ/519/533
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have compiled an X-ray catalog of optically selected rich clusters of galaxies observed by the Position Sensitive Proportional Counter (PSPC) during the pointed GO phase of the ROSAT mission. This paper contains a systematic X-ray analysis of 150 clusters with an optical richness classification of R>=2 from the Abell, Corwin, & Olowin (1989; ACO) catalog. All clusters were observed within 45' of the optical axis of the telescope during pointed PSPC observations. For each cluster, we calculate: the net 0.5-2.0keV PSPC count rate (or 4{sigma} upper limit) in a 1Mpc radius aperture, 0.5-2.0keV flux and luminosity, bolometric luminosity, and X-ray centroid. The cluster sample is then used to examine correlations between the X-ray and optical properties of clusters, derive the X-ray luminosity function of clusters with different optical classifications, and obtain a quantitative estimate of contamination (i.e., the fraction of clusters with an optical richness significantly overestimated due to interloping galaxies) in the ACO catalog.
- ID:
- ivo://CDS.VizieR/J/A+AS/129/87
- Title:
- ROSAT RASS II observations of IRAS galaxies
- Short Name:
- J/A+AS/129/87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 120000 X-ray sources detected in the RASS II processing of the ROSAT All-Sky Survey are correlated with the 14315 IRAS galaxies selected from the IRAS Point Source Catalogue: 372 IRAS galaxies show X-ray emission within a distance of 100 arcsec from the infrared position. By inspecting the structure of the X-ray emission in overlays on optical images we quantify the likelihood that the X-rays originate from the IRAS galaxy. For 197 objects the soft X-ray emission is very likely associated with the IRAS galaxy. Their soft X-ray properties are determined and compared with their far-infrared emission.
- ID:
- ivo://CDS.VizieR/J/ApJ/897/122
- Title:
- Rotational velocities for PHANGS sample of galaxies
- Short Name:
- J/ApJ/897/122
- Date:
- 11 Mar 2022
- Publisher:
- CDS
- Description:
- We present kinematic orientations and high-resolution (150pc) rotation curves for 67 main-sequence star-forming galaxies surveyed in CO (2-1) emission by PHANGS-ALMA. Our measurements are based on the application of a new fitting method tailored to CO velocity fields. Our approach identifies an optimal global orientation as a way to reduce the impact of nonaxisymmetric (bar and spiral) features and the uneven spatial sampling characteristic of CO emission in the inner regions of nearby galaxies. The method performs especially well when applied to the large number of independent lines of sight contained in the PHANGS CO velocity fields mapped at 1" resolution. The high-resolution rotation curves fitted to these data are sensitive probes of mass distribution in the inner regions of these galaxies. We use the inner slope as well as the amplitude of our fitted rotation curves to demonstrate that CO is a reliable global dynamical mass tracer. From the consistency between photometric orientations from the literature and kinematic orientations determined with our method, we infer that the shapes of stellar disks in the mass range of log(M*(M{odot}))=9.0-10.9 probed by our sample are very close to circular and have uniform thickness.
- ID:
- ivo://CDS.VizieR/J/AJ/154/41
- Title:
- Rotational velocities of M33
- Short Name:
- J/AJ/154/41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new deep HI survey of the galaxy Messier 33 is presented, based on observations obtained at the Dominion Radio Astrophysical Observatory. We observe a perturbed outer gas distribution and kinematics in M33, and confirm the disk warping as a significant twist of the major axis of the velocity field, although no strong tilt is measured, in agreement with previous work. Evidence for a new low-brightness HI component with anomalous velocity is reported. It harbors a large velocity scatter, as its kinematics both exceeds and lags the rotation of the disk, and leaks in the forbidden velocity zone of apparent counterrotation. The observations also reveal wide and multiple-peak HI profiles that can be partly explained by crowded orbits in the framework of the warp model. Asymmetric motions are identified in the velocity field as possible signatures of a lopsided potential and the warp. The mass distribution modeling of the hybrid H{alpha}-HI rotation curve favors a cuspy dark matter halo with a concentration in disagreement with the {Lambda}CDM dark halo mass-concentration relationship. The total mass enclosed in 23kpc is 8,10^10^M_{Sun}_, of which 11% are stars and gas. At the virial radius of the cuspy halo, the resulting total mass is 5,10^11^M_{Sun}_, but with a baryonic mass fraction of only 2%. This strongly suggests a more realistic radius encompassing the total mass of M33 that is well smaller than the virial radius of the halo, possibly comparable to the size of the HI disk.
- ID:
- ivo://CDS.VizieR/J/ApJ/785/63
- Title:
- Rotation curve of the Milky Way
- Short Name:
- J/ApJ/785/63
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The rotation curve (RC) of our Galaxy, the Milky Way, is constructed starting from its very inner regions (few hundred parsecs) out to a large galactocentric distance of ~200 kpc using kinematical data on a variety of tracer objects moving in the gravitational potential of the Galaxy, without assuming any theoretical models of the visible and dark matter (DM) components of the Galaxy. We study the effect on the RC due to the uncertainties in the values of the Galactic constants (GCs) R_0_ and V_0_ (these being the Sun's distance from and circular rotation speed around the Galactic center, respectively) and the velocity anisotropy parameter {beta} of the halo tracer objects used for deriving the RC at large galactocentric distances. The resulting RC in the disk region is found to depend significantly on the choice of the GCs, while the dominant uncertainty in the RC at large distances beyond the stellar disk comes from the uncertainty in the value of {beta}. In general we find that the mean RC steadily declines at distances beyond ~60 kpc, independently of the value of {beta}. Also, at a given radius, the circular speed is lower for larger values of {beta} (i.e., for more radially biased velocity anisotropy). Considering that the largest possible value of {beta} is unity, which corresponds to stellar orbits being purely radial, our results for the case of {beta}=1 give a lower limit to the total mass of the Galaxy within ~200 kpc, M(200 kpc)>~(6.8+/-4.1)x10^11^ M_{sun}_, independently of any model of the DM halo of the Galaxy.
- ID:
- ivo://CDS.VizieR/J/PAZh/27/250
- Title:
- Rotation curves for 135 edge-on galaxies
- Short Name:
- J/PAZh/27/250
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The table contains parameters for 135 edge-on galaxies. The observations were carried out with the 6-m Special Astrophysical Observatory telescope.
- ID:
- ivo://CDS.VizieR/J/AJ/114/2402
- Title:
- Rotation curves of early-type galaxies
- Short Name:
- J/AJ/114/2402
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Optical long-slit rotation curves have been studied for 304 northern Sb-Sc galaxies from the Courteau-Faber (CF) sample designed for Tully-Fischer (TF) applications; r-band photometry exists also for each galaxy of the sample. The procedure of rotation curve (RC) extraction and construction of optical profiles are analogous to 21cm integrated linewidths. More than 20% of the galaxies were observed twice or more, allowing for a proper determination of systematic errors. Various measures of maximum rotational velocity to be used as input in the TF relation are tested on the basis of their repeatability, minimization of TF scatter, and match with 21cm linewidths. The best measure of TF velocity, V2.2 is given at the location of peak rotational velocity of a pure exponential disk. An alternative measure to V2.2 which makes no assumption about the luminosity profile or shape of the rotation curve is Vhist, the 20% width of the velocity histogram, though the match with 21cm linewidths is not good. The paper shows that optical TF calibrations yield internal scatter comparable to, if not smaller than, the best calibrations based on single-dish 21cm radio linewidths. Tables 6 and 7 contain the values of the parameters fitting the rotation curves of two samples of galaxies: the CF (Courteau-Faber) sample (table6) and the MAT (Mathewson et al., 1992ApJS...81..413M) sample (table7). Two fitting models were used: the ArcTan function (Model 1) where the velocity varies as v(r) = v(0) + K . arctan(R) (R being (r-r_0_)/r_t_) and a multi-parameter function (Model 2) modelling the rotation curve close to a solid-body close to the rotation center, and close to a flat rotation at large distances (see section 5 of the paper).
