- ID:
- ivo://CDS.VizieR/J/MNRAS/461/3443
- Title:
- M31 deepest Chandra catalogue of point sources
- Short Name:
- J/MNRAS/461/3443
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This study represents the most sensitive Chandra X-ray point source catalogue of M31. Using 133 publicly available Chandra ACIS-I/S observations totalling ~1Ms, we detected 795 X-ray sources in the bulge, north-east, and south-west fields of M31, covering an area of ~=0.6deg^2^, to a limiting unabsorbed 0.5-8.0keV luminosity of ~10^34^erg/s. In the inner bulge, where exposure is approximately constant, X-ray fluxes represent average values because they were determined from many observations over a long period of time. Similarly, our catalogue is more complete in the bulge fields since monitoring allowed more transient sources to be detected. The catalogue was cross-correlated with a previous XMM-Newton catalogue of M31's D_25_ isophote consisting of 1948 X-ray sources, with only 979 within the field of view of our survey. We found 387 (49 per cent) of our Chandra sources (352 or 44 per cent unique sources) matched to within 5 arcsec of 352 XMM-Newton sources. Combining this result with matching done to previous Chandra X-ray sources we detected 259. new sources in our catalogue. We created X-ray luminosity functions (XLFs) in the soft (0.5-2.0keV) and hard (2.0-8.0keV) bands that are the most sensitive for any large galaxy based on our detection limits. Completeness-corrected XLFs show a break around ~=1.3x10^37^erg/s, consistent with previous work. As in past surveys, we find that the bulge XLFs are flatter than the disc, indicating a lack of bright high-mass X-ray binaries in the disc and an aging population of low-mass X-ray binaries in the bulge.
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Search Results
572. MDFC Version 10
- ID:
- ivo://CDS.VizieR/II/361
- Title:
- MDFC Version 10
- Short Name:
- II/361
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Mid-infrared stellar Diameters and Fluxes compilation Catalogue (MDFC) dedicated to long-baseline interferometry at mid-infrared wavelengths (3-13um). It gathers data for half a million stars, i.e. nearly all the stars of the Hipparcos-Tycho catalogue whose spectral type is reported in the SIMBAD data base. We cross-match 26 data bases to provide basic information, binarity elements, angular diameter, magnitude and flux in the near and mid-infrared, as well as flags that allow us to identify the potential calibrators. The catalogue covers the entire sky with 465857 stars, mainly dwarfs and giants from B to M spectral types closer than 18kpc. The smallest reported values reach 0.16uJy in L and 0.1uJy in N for the flux, and 2-microarcsec for the angular diameter. We build four lists of calibrator candidates for the L and Nbands suitable with the Very Large Telescope Interferometer (VLTI) sub- and main arrays using the MATISSE instrument. We identify 1621 candidates for L and 44 candidates for N with the Auxiliary Telescopes (ATs), 375 candidates for both bands with the ATs, and 259 candidates for both bands with the Unit Telescopes (UTs). Predominantly cool giants, these sources are small and bright enough to belong to the primary lists of calibrator candidates. In the near future, we plan to measure their angular diameter with 1 per cent accuracy.
573. MegaZ-LRG catalogue
- ID:
- ivo://CDS.VizieR/J/MNRAS/375/68
- Title:
- MegaZ-LRG catalogue
- Short Name:
- J/MNRAS/375/68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the construction of MegaZ-LRG, a photometric redshift catalogue of over one million luminous red galaxies (LRGs) in the redshift range 0.4<z<0.7 with limiting magnitude i<20. The catalogue is selected from the imaging data of the Sloan Digital Sky Survey (SDSS) Data Release 4. The 2dF-SDSS LRG and Quasar (2SLAQ) spectroscopic redshift catalogue of 13000 intermediate-redshift LRGs provides a photometric redshift training set, allowing use of ANNZ, a neural network-based photometric-redshift estimator. The rms photometric redshift accuracy obtained for an evaluation set selected from the 2SLAQ sample is z=0.049 averaged over all galaxies, and z=0.040 for a brighter subsample (i<19.0). The catalogue is expected to contain ~5 per cent stellar contamination. The ANNZ code is used to compute a refined star/galaxy probability based on a range of photometric parameters; this allows the contamination fraction to be reduced to 2 per cent with negligible loss of genuine galaxies. The MegaZ-LRG catalogue is publicly available on the World Wide Web from http://www.2slaq.info .
- ID:
- ivo://CDS.VizieR/J/ApJS/237/36
- Title:
- Merging dwarf galaxies in the local universe
- Short Name:
- J/ApJS/237/36
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the largest publicly available catalog of interacting dwarf galaxies. It includes 177 nearby merging dwarf galaxies of stellar mass M*<10^10^M_{sun}_ and redshifts z<0.02. These galaxies are selected by visual inspection of publicly available archival imaging from two wide-field optical surveys (SDSS-III and the Legacy Survey), and they possess low-surface-brightness features that are likely the result of an interaction between dwarf galaxies. We list UV and optical photometric data that we use to estimate stellar masses and star formation rates. So far, the study of interacting dwarf galaxies has largely been done on an individual basis, and lacks a sufficiently large catalog to give statistics on the properties of interacting dwarf galaxies, and their role in the evolution of low-mass galaxies. We expect that this public catalog can be used as a reference sample to investigate the effects of the tidal interaction on the evolution of star formation, and the morphology/structure of dwarf galaxies. Our sample is overwhelmingly dominated by star-forming galaxies, and they are generally found significantly below the red sequence in the color-magnitude relation. The number of early-type galaxies is only 3 out of 177. We classify them, according to observed low-surface-brightness features, into various categories including shells, stellar streams, loops, antennae, or simply interacting. We find that dwarf-dwarf interactions tend to prefer the low-density environment. Only 41 out of the 177 candidate dwarf-dwarf interaction systems have giant neighbors within a sky-projected distance of 700kpc and a line-of-sight radial velocity range +/-700km/s, and compared to the LMC-SMC, they are generally located at much larger sky-projected distances from their nearest giant neighbors.
- ID:
- ivo://CDS.VizieR/J/A+A/600/A28
- Title:
- Merging galaxies in Pan-STARR
- Short Name:
- J/A+A/600/A28
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We studied the r'-, z'-, and y'-band images of merging galaxies from the observations of the Panoramic Survey Telescope & Rapid Response System (Pan-STARRS). The merging galaxies were selected from our merging catalog that was created by checking the images of the Red-Sequence Cluster Survey 2 from the observations of the Canada France Hawaii Telescope By using the homomorphic-aperture, we determined the photometric results of these merging systems. To obtain accurate photometry, we calibrated the Pan-STARRS r'-, z'-, and y'-band data to match the results of Sloan Digital Sky Survey Data Release 9. We also investigated the stellar masses of the merging galaxies by comparing the Wide-field Infrared Survey Explorer 3.4um emission with the calibrated y'-band data. We present a catalog of the r'-, z'-, and y'-band photometric results for 4698 merging galaxies. For extended sources, our results suggest that the homomorphic-aperture method can obtain more reasonable results than the Desktop Virtual Observatory photometry. We derived new relations between the Pan-STARRS y'-band luminosities and the stellar masses of the merging galaxies. Our results show that the stellar masses of the merging galaxies range from 10^8^ to 10^13^M_{sun}_; some of the dry mergers could be as massive as 10^13^M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/A+A/602/A100
- Title:
- Merging groups and clusters from the SDSS data
- Short Name:
- J/A+A/602/A100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Galaxy groups and clusters are the main tools to test cosmological models and to study the environmental effect of galaxy formation. This work aims to provide a catalogue of galaxy groups/clusters and potentially merging systems based on the SDSS main galaxy survey. We identify galaxy groups and clusters using the modified friends-of-friends (FoF) group finder that is designed specifically for flux-limited galaxy surveys. FoF group membership is refined by multimodality analysis to find subgroups and by using the group virial radius and escape velocity to expose unbound galaxies. We look for merging systems by comparing distances between group centres with group radii. The analysis results in a catalogue of 88 662 galaxy groups with at least two members. Among them are 6873 systems with at least 6 members which we consider as more reliable groups. We find 498 group mergers with up to six groups.
- ID:
- ivo://CDS.VizieR/J/AJ/140/2052
- Title:
- MESS: Multi-wavelength Extreme Starburst Sample
- Short Name:
- J/AJ/140/2052
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper introduces the Multi-wavelength Extreme Starburst Sample (MESS), a new catalog of 138 star-forming galaxies (0.1<z<0.3) optically selected from the Sloan Digital Sky Survey using emission line strength diagnostics to have a high absolute star formation rate (SFR; minimum 11M_{sun}_/yr with median SFR~61M_{sun}_/yr based on a Kroupa initial mass function). The MESS was designed to complement samples of nearby star-forming galaxies such as the luminous infrared galaxies (LIRGs) and ultraviolet luminous galaxies (UVLGs). Observations using the Multi-band Imaging Photometer (24, 70, and 160um channels) on the Spitzer Space Telescope indicate that the MESS galaxies have IR luminosities similar to those of LIRGs, with an estimated median total IR luminosity L_IR_=~3x10^11^L_{sun}_.
- ID:
- ivo://CDS.VizieR/J/A+A/589/A109
- Title:
- Metal enrichment in semi-analytical model
- Short Name:
- J/A+A/589/A109
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Gas flows play a fundamental role in galaxy formation and evolution, providing the fuel for the star formation process. These mechanisms leave an imprint in the amount of heavy elements that enrich the interstellar medium (ISM). Thus, the analysis of this metallicity signature provides additional constraint on the galaxy formation scenario. We aim to discriminate between four different galaxy formation models based on two accretion scenarios and two different star formation recipes. We address the impact of a bimodal accretion scenario and a strongly regulated star formation recipe on the metal enrichment process of galaxies. We present a new extension of the eGalICS model, which allows us to track the metal enrichment process in both stellar populations and in the gas phase. Based on stellar metallicity bins from 0 to 2.5Z_{sun}_, our new chemodynamical model is applicable for situations ranging from metal-free primordial accretion to very enriched interstellar gas contents. We use this new tool to predict the metallicity evolution of both the stellar populations and gas phase. We compare these predictions with recent observational measurements. We also address the evolution of the gas metallicity with the star formation rate (SFR). We then focus on a sub-sample of Milky Way-like galaxies. We compare both the cosmic stellar mass assembly and the metal enrichment process of such galaxies with observations and detailed chemical evolution models.
- ID:
- ivo://CDS.VizieR/J/MNRAS/403/1625
- Title:
- Method for orientation angles of galaxies
- Short Name:
- J/MNRAS/403/1625
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A method is proposed for the determination of the position and inclination angles of the plane of a spiral galaxy based on the assumption that every spiral arm is a monotonic function of the radius against azimuthal angle. This method may yield more accurate results than the more commonly employed isophote method, which is subject to a number of drawbacks. Analytical study, calibration against other methods and examples of application of the proposed method to real galaxies are presented.
- ID:
- ivo://CDS.VizieR/J/A+AS/136/519
- Title:
- Mg2 indices for early-type galaxies
- Short Name:
- J/A+AS/136/519
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 210 new measurements of the central absorption line-strength Mg_2_ index for 87 early-type galaxies drawn from the Prugniel & Simien (1996, Cat. <J/A+A/309/749>) sample. 28 galaxies were not observed before. The results are compared to measurements published previously as available in HYPERCAT, and rescaled to the Lick system. The mean individual internal error on these measurements is 0.009mag+/-0.003mag and the mean external error is 0.012mag+/-0.002mag for this series of measurements. These data are also available from HYPERCAT.