- ID:
- ivo://CDS.VizieR/J/A+A/534/A55
- Title:
- Deep XMM-Newton Survey of M31
- Short Name:
- J/A+A/534/A55
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The largest Local Group spiral galaxy, M31, has been completely imaged for the first time, obtaining a luminosity lower limit about 10^35^erg/s in the 0.2-4.5keV band. Our XMM-Newton EPIC survey combines archival observations along the major axis, from June 2000 to July 2004, with observations taken between June 2006 and February 2008 that cover the remainder of the D_25_ ellipse. The main goal of the paper is to study X-ray source populations of M31. An X-ray catalogue of 1897(*) sources was created with 914 detected for the first time. Source classification and identification were based on X-ray hardness ratios, spatial extent of the sources, and cross correlation with catalogues in the X-ray, optical, infrared and radio wavelengths. We also analysed the long-term variability of the X-ray sources and this variability allows us to distinguish between X-ray binaries and active galactic nuclei (AGN). Furthermore, supernova remnant classifications of previous studies that did not use long-term variability as a classification criterion could be validated. Including previous Chandra and ROSAT observations in the long-term variability study allowed us to detect additional transient or at least highly variable sources, which are good candidate X-ray binaries. (*) the final catalog of table5 icludes 1948 sources.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/438/507
- Title:
- Degree of lopsidedness for galaxies
- Short Name:
- J/A+A/438/507
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We quantify the degree of lopsidedness for a sample of 149 galaxies observed in the near-infrared from the Ohio State University Bright Galaxy Survey (OSUBGS, Eskridge et al. 2002, Cat. <J/ApJS/143/73>) sample, and try to explain the physical origin of the observed disk lopsidedness. We confirm previous studies, but for a larger sample, that a large fraction of galaxies have significant lopsidedness in their stellar disks, measured as the Fourier amplitude of the m=1 component normalised to the average or m=0 component in the surface density. Late-type galaxies are found to be more lopsided, while the presence of m=2 spiral arms and bars is correlated with disk lopsidedness. We also show that the m=1 amplitude is uncorrelated with the presence of companions. Numerical simulations were carried out to study the generation of m=1 via different processes: galaxy tidal encounters, galaxy mergers, and external gas accretion with subsequent star formation. These simulations show that galaxy interactions and mergers can trigger strong lopsidedness, but do not explain several independent statistical properties of observed galaxies. To explain all the observational results, it is required that a large fraction of lopsidedness results from cosmological accretion of gas on galactic disks, which can create strongly lopsided disks when this accretion is asymmetrical enough.
- ID:
- ivo://CDS.VizieR/J/ApJ/799/148
- Title:
- DEIMOS galaxy sample at z~0.7
- Short Name:
- J/ApJ/799/148
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Scaling relations between galaxy structures and dynamics have been studied extensively for early- and late-type galaxies, both in the local universe and at high redshifts. The abundant differences between the properties of disky and elliptical, or star-forming and quiescent, galaxies seem to be characteristic of the local universe; such clear distinctions begin to disintegrate as observations of massive galaxies probe higher redshifts. In this paper we investigate the existence of the mass fundamental plane of all massive galaxies ({sigma}>~100km/s). This work includes local galaxies (0.05<z<0.07) from the Sloan Digital Sky Survey, in addition to 31 star-forming and 72 quiescent massive galaxies at intermediate redshift (z~0.7) with absorption-line kinematics from deep Keck-DEIMOS spectra and structural parameters from Hubble Space Telescope imaging. In two-parameter scaling relations, star-forming and quiescent galaxies differ structurally and dynamically. However, we show that massive star-forming and quiescent galaxies lie on nearly the same mass fundamental plane, or the relationship between stellar mass surface density, stellar velocity dispersion, and effective radius. The scatter in this relation (measured about log{sigma}) is low: 0.072dex (0.055dex intrinsic) at z~0 and 0.10dex (0.08dex intrinsic) at z~0.7. This 3D surface is not unique: virial relations, with or without a dependence on luminosity profile shapes, can connect galaxy structures and stellar dynamics with similar scatter. This result builds on the recent finding that mass fundamental plane has been stable for early-type galaxies since z~2. As we now find that this also holds for star-forming galaxies to z~0.7, this implies that these scaling relations of galaxies will be minimally susceptible to progenitor biases owing to the evolving stellar populations, structures, and dynamics of galaxies through cosmic time.
- ID:
- ivo://CDS.VizieR/J/ApJ/858/77
- Title:
- DEIMOS 10K spectroscopic survey in COSMOS field
- Short Name:
- J/ApJ/858/77
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 10718 objects in the COSMOS field, observed through multi-slit spectroscopy with the Deep Imaging Multi-Object Spectrograph (DEIMOS) on the Keck II telescope in the wavelength range ~5500-9800{AA}. The catalog contains 6617 objects with high-quality spectra (two or more spectral features), and 1798 objects with a single spectroscopic feature confirmed by the photometric redshift. For 2024 typically faint objects, we could not obtain reliable redshifts. The objects have been selected from a variety of input catalogs based on multi-wavelength observations in the field, and thus have a diverse selection function, which enables the study of the diversity in the galaxy population. The magnitude distribution of our objects is peaked at I_AB_~23 and K_AB_~21, with a secondary peak at K_AB_~24. We sample a broad redshift distribution in the range 0<z<6, with one peak at z~1, and another one around z~4. We have identified 13 redshift spikes at z>0.65 with chance probabilities <4x10^-4^, some of which are clearly related to protocluster structures of sizes >10Mpc. An object-to-object comparison with a multitude of other spectroscopic samples in the same field shows that our DEIMOS sample is among the best in terms of fraction of spectroscopic failures and relative redshift accuracy. We have determined the fraction of spectroscopic blends to about 0.8% in our sample. This is likely a lower limit and at any rate well below the most pessimistic expectations. Interestingly, we find evidence for strong lensing of Ly{alpha} background emitters within the slits of 12 of our target galaxies, increasing their apparent density by about a factor of 4.
- ID:
- ivo://CDS.VizieR/VII/234
- Title:
- DENIS catalog of galaxies
- Short Name:
- VII/234
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new, extended and improved version of the provisional I-band catalog of DENIS galaxies. Galaxies not cross-identified with already known galaxies have been visually controlled using the DSS1 images and, occasionally, the coordinates were remeasured. The typical accuracy of coordinates is about 2". The typical error on I-band magnitude is about 0.2mag. The final catalog gives the most common names, the J2000 coordinates, the I-band magnitude, the diameter, the axis ratio and the position angle for about 43000 galaxies. It covers roughly 67% of the southern hemisphere. It is homogeneously sampled up to I=14.5 mag. The data are also available via the LEDA database.
- ID:
- ivo://CDS.VizieR/J/A+A/363/62
- Title:
- DENIS galaxies around 16h15m -30deg
- Short Name:
- J/A+A/363/62
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- From a visual inspection of J and K images obtained within the Deep Near Infrared Survey (DENIS) we detected 37 noteworthy galaxies near the galactic plane (|b|<15{deg}). Most of these galaxies are yet uncatalogued. They have either a large dimension (more than 1arcmin in J-band) or a position very close to the galactic plane (|b|<3{deg}). Some of these galaxies are simply not visible on the Digitized Sky Survey. Among them 15 galaxies are suspected to be spirals and could be detected from HI observations. Several large galaxies near the assumed position of the Great Attractor suggests that a concentration of galaxies may be present around the equatorial position: {alpha}_2000_=16h15m, {delta}_2000_=-30{deg}. An inspection of this field from the Digitized Sky Survey and from available 2MASS data confirms the presence of extragalactic structures.
- ID:
- ivo://CDS.VizieR/J/A+A/387/1
- Title:
- DENIS galaxies behind the Milky Way
- Short Name:
- J/A+A/387/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A search has been undertaken at Lyon Observatory to identify, by eye, galaxy candidates at galactic latitudes lower than +/-15 degrees on the DENIS J and K-band images. This paper presents a list of 2028 objects that were serendipitously detected throughout the DENIS survey. Cross-identification with galaxy entries in the LEDA Database has been performed. Comparison with the second release of the 2MASS survey led to a satisfactory agreement of J band magnitudes (std. dev.=0.3mag). The distribution of galaxy candidates along the Galactic Plane shows a concentration near the galactic longitude l=305deg. As a by product of this inspection of J and K images some interesting galactic objects were found (star clusters and nebulae).
- ID:
- ivo://CDS.VizieR/J/A+A/421/595
- Title:
- Deprojecting spiral galaxies method
- Short Name:
- J/A+A/421/595
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use two new methods developed recently (Barbera et al., 2004, Cat. <J/A+A/415/849>), as well as information obtained from the literature, to calculate the orientation parameters of the spiral galaxies in the Ohio State University Bright Spiral Galaxy Survey (OSUBSGS). We compare the results of these methods with data from the literature, and find in general good agreement. We provide a homogeneous set of mean orientation parameters which can be used to approximately deproject the disks of the galaxies and facilitate a number of statistical studies of galaxy properties.
- ID:
- ivo://CDS.VizieR/J/A+A/415/849
- Title:
- Deprojection of spiral galaxies
- Short Name:
- J/A+A/415/849
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present two methods that can be used to deproject spirals, based on Fourier analysis of their images, and discuss their potential and restrictions. Our methods perform particularly well for galaxies more inclined than 50 degrees or for non-barred galaxies more inclined than 35 degrees. They are fast and straightforward to use, and thus ideal for large samples of galaxies. Moreover, they are very robust for low resolutions and thus are appropriate for samples of cosmological interest. The relevant software is available from us upon request. We use these methods to determine the values of the position and inclination angles for a sample of 81 spiral galaxies contained in the Frei et al. (1996AJ....111..174F) sample. We compare our results with the values found in the literature, based on other methods. We find statistically very good agreement.
- ID:
- ivo://CDS.VizieR/J/AJ/81/807
- Title:
- Deprojection of the r^1/4^ law tables
- Short Name:
- J/AJ/81/807
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A spherical galaxy with reduced surface brightness, J=B({alpha})/B_e_, obeying the r^1/4^ law, logJ=-3.3307 ({alpha}^1/4^-1), where {alpha} is the reduced radius, {alpha}=r/r_e_ (r_e_ is the effective radius), is deprojected to find the corresponding space density, mass, mean density, force, potential, escape velocity, and potential energy at each point in the galaxy. Numerical tabulations to five significant figures are given for 124 points in the range 10^-6^<=R/r_e_<=260. In addition the projected surface brightness B({alpha}) and integrated luminosity within {alpha} are tabulated for the range 10^-6^<={alpha}=r/r_e_<=260. Conversion factors to cgs units and to M_{sun}_, pc, km/s, L_{sun}_ units are given. Asymptotic expansions for the space density {rho}(s) in the ranges s=<10^-4^ and s>=10^-1^ are derived, and it is demonstrated that the projection of the expansion for s<=10^-1^ is almost indistinguishable from the r^1/4^ law itself, apart from a small excess of luminosity in the central regions. Formulae and numerical tables of the luminosity distribution are given for use in galaxy photometry. Relations between the total galactic mass M_T_, the effective radius r_e_, the velocity dispersion {sigma}_v_, the central density {rho}_c_ and the mass M_N_ and radius R_N_ of the nucleus are derived. Here the "nucleus" is defined as the region within which stars having a velocity equal to the mean velocity dispersion in space, {sigma}_v_.
