- ID:
- ivo://CDS.VizieR/J/ApJ/857/51
- Title:
- Measuring dark energy properties with PS1 SNe. II.
- Short Name:
- J/ApJ/857/51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use 1169 Pan-STARRS supernovae (SNe) and 195 low-z (z<0.1) SNe Ia to measure cosmological parameters. Though most Pan-STARRS SNe lack spectroscopic classifications, in a previous paper we demonstrated that photometrically classified SNe can be used to infer unbiased cosmological parameters by using a Bayesian methodology that marginalizes over core-collapse (CC) SN contamination. Our sample contains nearly twice as many SNe as the largest previous SN Ia compilation. Combining SNe with cosmic microwave background (CMB) constraints from Planck, we measure the dark energy equation-of-state parameter w to be -0.989+/-0.057 (stat+sys). If w evolves with redshift as w(a)=w0+wa(1-a), we find w0=-0.912+/-0.149 and wa=-0.513+/-0.826. These results are consistent with cosmological parameters from the Joint Light-curve Analysis and the Pantheon sample. We try four different photometric classification priors for Pan-STARRS SNe and two alternate ways of modeling CC SN contamination, finding that no variant gives a w differing by more than 2% from the baseline measurement. The systematic uncertainty on w due to marginalizing over CC SN contamination, {sigma}_w_^CC^=0.012, is the third-smallest source of systematic uncertainty in this work. We find limited (1.6{sigma}) evidence for evolution of the SN color-luminosity relation with redshift, a possible systematic that could constitute a significant uncertainty in future high-z analyses. Our data provide one of the best current constraints on w, demonstrating that samples with ~5% CC SN contamination can give competitive cosmological constraints when the contaminating distribution is marginalized over in a Bayesian framework.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+AS/134/115
- Title:
- Medicina 6.7GHz methanol masers survey
- Short Name:
- J/A+AS/134/115
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- File table2 contains the name of the sources and their coordinates (1950) observed, but not detected, with the Medicina Radiotelescope at 6.7GHz in 1995, March. Source are associated with one or more type of phenomena typical of star forming regions (see note 1 for code description). The number of non detected sources is 387.
1053. 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/ApJ/877/13
- Title:
- Member stars of the GD-1 tidal stream
- Short Name:
- J/ApJ/877/13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- With the photometric data from the SDSS survey, the spectroscopic data from the SDSS/SEGUE and the LAMOST surveys, and the astrometric data from the Gaia DR2, we have identified 67 highly probable member stars of the GD-1 cold stellar stream spread along almost its entire length (i.e., from 126{deg} to 203{deg} in R.A.). With the accurate spectroscopic (i.e., metallicity and line-of-sight velocity) and astrometric (i.e., proper motions) information, the position-velocity diagrams, i.e., {phi}_1_-{mu}_{alpha}_, {phi}_1_-{mu}_{delta}_, and {phi}_1_-v_gsr_, of the GD-1 stream are well mapped. The stream has an average metallicity [Fe/H]=-1.96. The rich information of member stars of the stream now available allow one not only to model its origin, but also to place strong constraints on the mass distribution and the gravitational potential of the Milky Way.
- 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/AJ/127/1883
- Title:
- Merging galaxies in SDSS EDR
- Short Name:
- J/AJ/127/1883
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new catalog of merging galaxies obtained through an automated systematic search routine. The 1479 new pairs of merging galaxies were found in ~462 square degrees of the Sloan Digital Sky Survey Early Data Release (SDSS EDR, Cat. <J/AJ/123/567>) photometric data, and the pair catalog is complete for galaxies in the magnitude range 16.0<=g*<=20. The selection algorithm, implementing a variation on the original Karachentsev criteria, proved to be very efficient and fast. Merging galaxies were selected such that the intergalaxy separations were less than the sum of the component galaxies' radii. We discuss the characteristics of the sample in terms of completeness, pair separation, and the Holmberg effect. We also present an on-line atlas of images for the SDSS EDR pairs obtained using the corrected frames from the SDSS EDR database. The atlas images also include the relevant data for each pair member. This catalog will be useful for conducting studies of the general characteristics of merging galaxies, their environments, and their component galaxies. The redshifts for a subset of the interacting and merging galaxies and the distribution of angular sizes for these systems indicate the SDSS provides a much deeper sample than almost any other wide-area catalog to date.
- ID:
- ivo://CDS.VizieR/B/avo.rad
- Title:
- MERLIN+VLA images of HDF/HFF sources
- Short Name:
- B/avo.rad
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 18 days of MERLIN data and 42 hours of A-array VLA data at 1.4 GHz have been combined to image a 10 arcminute field centred on the Hubble Deep Field. This area includes both the Hubble Deep and Flanking Fields. A complete sample of 92 sources with flux densities above 40µJy have been detected using the VLA data, and imaged with the MERLIN+VLA combination at resolutions of 0.2, 0.3 and 0.5 arcsecond. These are the most sensitive 1.4 GHz images yet made, with rms noise levels of 3.3µJy/beam in the 0.2 arcsecond images. Virtually all the objects are resolved by the MERLIN+VLA combination images showing that they have angular sizes in the range 0.2 to 3 arcseconds, typically smaller than the sizes of the optical galaxy images. In addition to the imaging of 92 sources found with the VLA alone, the central 3 arcminutes, which encloses the HDF, has been separately imaged with the MERLIN+VLA combination at the full 3.3µJy/beam sensitivity to search for compact sources fainter than 40µJy. No additional sources were found that were not previously detected by the VLA, indicating that such sources are heavily resolved with MERLIN and hence must have typical angular sizes >0.5 arcseconds. In addition to the images, high quality astrometry is an equally important product of this work allowing reliable source identification in a crowded field. Radio sources associated with compact galaxies have been used to align both the HST WFPC2 frames and a CFHT optical field to the ICRF. The HST optical field has been aligned to better than 50 mas in the Deep Field itself, and to ∼150 mas in the outer parts of the Flanking Fields. The proportion of starburst systems is found to increase with decreasing source strength. At fluxes below 100µJy in excess of 70% of the µJy sources are found to be starburst type systems associated with major disc galaxies in the redshift range 0.3 - 1.3. Some 40% of the brighter sources are found to be intermediate luminosity AGN systems identified with galxies in a similar redshift range. Around 85% of the sources are identified with galaxies brighter than I=25mag. The remaining 15% are associated with optically faint systems close to or beyond the HDF limit; many of these may be dust-shrouded starburst galaxies at high redshift (z>3). Approaching half the sources in the 10 arcminute field are detected in X-rays by the Chandra Satellite. The X-ray detection rate appears to be uncorrelated with the radio source classification.
- ID:
- ivo://CDS.VizieR/J/AJ/136/2441
- Title:
- Metallicity of RR0 Lyrae in the galactic bulge
- Short Name:
- J/AJ/136/2441
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present metallicities of 2690 RR0 Lyrae stars observed toward the MACHO Survey fields in the Galactic bulge. These [Fe/H] values are based upon an empirically-calibrated relationship that uses the Fourier coefficients of the light curve and are accurate to +/-0.2dex. The majority of the RR0 Lyrae stars in our sample are located in the Galactic bulge, but 255 RR0 stars are associated with the Sagittarius (Sgr) dwarf galaxy.
- ID:
- ivo://CDS.VizieR/J/ApJ/698/819
- Title:
- MgII and LRGs cross-correlation analysis
- Short Name:
- J/ApJ/698/819
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze the cross-correlation of MgII({lambda}2796, 2803) quasar absorption systems with luminous red galaxies (LRGs) from the Fifth Data Release (DR5) of the Sloan Digital Sky Survey. The absorption line sample consists of 2705 unambiguously intervening MgII absorption systems, detected at a 4{sigma} level, covering a redshift range (0.36<=z_abs_<=0.8) and a rest equivalent-width range of 0.8{AA}<=W^{lambda}2796^_r_<=5.0{AA}. We cross-correlate these absorbers with 1495604 LRGs with accurate photometric redshifts in the same redshift range and examine the relationship of MgII equivalent width and clustering amplitude.
