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- ID:
- ivo://CDS.VizieR/J/MNRAS/435/1680
- Title:
- SN Ia host galaxy properties
- Short Name:
- J/MNRAS/435/1680
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the stellar populations of Type Ia supernova (SN Ia) host galaxies using Sloan Digital Sky Survey (SDSS)-II spectroscopy. The main focus is on the relationships of SN Ia properties with stellar velocity dispersion and the stellar population parameters age, metallicity and element abundance ratios. We concentrate on a sub-sample of 84 SNe Ia from the SDSS-II Supernova Survey and find that SALT2 stretch factor values show the strongest dependence on stellar population age. Hence, more luminous SNe Ia appear in younger stellar progenitor systems. No statistically significant trends in the Hubble residual with any of the stellar population parameters studied are found. Moreover, the method of photometric stellar mass derivation affects the Hubble residual-mass relationship. For an extended sample (247 objects), including SNe Ia with SDSS host galaxy photometry only, the Hubble residual-mass relationship behaves as a sloped step function. In the high-mass regime, probed by our host spectroscopy sample, this relationship is flat. Below a stellar mass of ~2x10^10^M_{sun}_, i.e. close to the evolutionary transition mass of low-redshift galaxies, the trend changes dramatically such that lower mass galaxies possess lower luminosity SNe Ia after light-curve corrections. The sloped step function of the Hubble residual-mass relationship should be accounted for when using stellar mass as a further parameter for minimizing the Hubble residuals.
- ID:
- ivo://CDS.VizieR/J/MNRAS/445/2440
- Title:
- SN with associated Planck CMB temperatures
- Short Name:
- J/MNRAS/445/2440
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- By using the Planck map of the cosmic microwave background (CMB) radiation, we have checked and confirmed the existence of a correlation between supernova (SN) redshifts, z_SN_, and CMB temperature fluctuations at the SNe locations, T_SN_, which we previously reported for the Wilkinson Microwave Anisotropy Probe data. The Pearson correlation coefficient for the Planck data is r=+0.38+/-0.08, which indicates that the correlation is statistically significant (the signal is about 5{sigma} above the noise level). The correlation becomes even stronger for the Type Ia subsample of SNe, r_Ia_=+0.45+/-0.09, whereas for the rest of the SNe it is vanishing. By checking the slopes of the regression lines T_SN_/z_SN_ for Planck's different frequency bands, we have also excluded the possibility of this anomaly being caused by the Sunyaev-Zeldovich effect. The remaining possibility is some, unaccounted for, contribution to the CMB from distant (z>0.3) foreground through either the integrated Sachs-Wolfe effect or thermal emission from intergalactic matter.
- ID:
- ivo://CDS.VizieR/J/other/ApL/30.1
- Title:
- Southern catalogue of isolated pairs extension
- Short Name:
- J/other/ApL/30.1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The paper presents a sample of double galaxies selected from The Surface Photometry Catalog of the ESO-Uppsala Galaxies (Cat. <VII/115>) using the Karachentsev (1972: K72, Cat. <VII/77>) criteria. Considering the large and growing number of observing facilities in that hemisphere, the sample aims to supply investigators with targets as homogeneous as possible to those in the Northern Catalog of Isolated Pairs of Galaxies (K72) which have been studied in a large frequency range. The paper discusses the sample degree of completeness, separation and velocity distributions. First inferences are sketched from the morphological association of pair members and from the study of the Holmberg effect. Being the primary purpose of the paper to provide a tool to investigators, an Atlas of images for the 301 best candidate pairs obtained using the Digitized Sky Survey (The Digitized Sky Survey was produced at the Space Telescope Science Institute (ST ScI) under U.S. Government grant NAG W-2166) is given. The Atlas reports for each pair member the relevant data as obtained from the current literature.
- ID:
- ivo://CDS.VizieR/J/other/PASAu/10.140
- Title:
- Southern radio sources catalog
- Short Name:
- J/other/PASAu/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A list of 900 radio sources with positional accuracies better than 0.5" has been prepared from seventeen lists of radio source positions found in the literature. This compilation includes all such sources south of declination +48{deg} (the northern declination limit of the Compact Array of the Australia Telescope National Facility). Where available, optical identifications, optical magnitudes and redshifts are given as well as total-power flux densities.
- ID:
- ivo://CDS.VizieR/VII/142A
- Title:
- Southern Redshifts Catalogue
- Short Name:
- VII/142A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue provides a "best-estimate" of the heliocentric radial velocities of some 13000 galaxies south of Declination 0 degrees. It is based on over 17000 redshift measurements, from over 200 sources, either published or otherwise made public. Aside from redshift references, each entry includes flags as to whether the velocity is from optical or radio observations, or both, as well as an indication of the nature of any optical emission lines. Galaxies with velocities beyond 75000 km/s are not included. All entries have been made interactively, by one person (A.P.F.). The interaction was necessary because different investigators may use different names, quote slightly different positions, and obtain slightly different velocities for the same galaxy. Thus duplicate entries for the same galaxy are avoided (although a few may inevitably be included).
- ID:
- ivo://CDS.VizieR/J/MNRAS/457/2366
- Title:
- Southern ZOA galaxies 21cm HI-line
- Short Name:
- J/MNRAS/457/2366
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High-accuracy HI profiles and linewidths are presented for inclined ((b/a)^o^<0.5) spiral galaxies in the southern Zone of Avoidance (ZOA). These galaxies define a sample for use in the determinations of peculiar velocities using the near-infrared Tully-Fisher (TF) relation. The sample is based on the 394 HI-selected galaxies from the Parkes HI Zone of Avoidance survey (HIZOA). Follow-up narrow-band Parkes HI observations were obtained in 2010 and 2015 for 290 galaxies, while for the further 104 galaxies, sufficiently high signal-to-noise (S/N) spectra were available from the original HIZOA data. All 394 spectra are reduced and parametrized in the same systematic way. Five different types of linewidth measurements were derived, and a Bayesian mixture model was used to derive conversion equations between these five widths. Of the selected and measure galaxies, 342 have adequate signal to noise (S/N>=5) for use in TF distance estimation. The average value of the S/N ratio of the sample is 14.7. We present the HI parameters for these galaxies. The sample will allow a more accurate determination of the flow field in the southern ZOA which bisects dynamically important large-scale structures such as Puppis, the Great Attractor, and the Local Void.
- ID:
- ivo://CDS.VizieR/J/MNRAS/422/3370
- Title:
- Spatial variation in fine-structure constant
- Short Name:
- J/MNRAS/422/3370
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Quasar absorption lines provide a precise test of whether the fine-structure constant, {alpha}, is the same in different places and through cosmological time. We present a new analysis of a large sample of quasar absorption-line spectra obtained using the Ultraviolet and Visual Echelle Spectrograph (UVES) on the Very Large Telescope (VLT) in Chile. We apply the many-multiplet method to derive values of {DELTA}{alpha}/{alpha}==({alpha}z-{alpha}0)/{alpha}0 from 154 absorbers, and combine these values with 141 values from previous observations at the Keck Observatory in Hawaii.
- ID:
- ivo://CDS.VizieR/J/MNRAS/471/364
- Title:
- Spectral curvature values for AGN sample
- Short Name:
- J/MNRAS/471/364
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To fully understand cosmic black hole growth, we need to constrain the population of heavily obscured active galactic nuclei (AGNs) at the peak of cosmic black hole growth (z~1-3). Sources with obscuring column densities higher than 10^24^atoms/cm^2^, called Compton-thick (CT) AGNs, can be identified by excess X-ray emission at ~20-30keV, called the 'Compton hump'. We apply the recently developed Spectral Curvature (SC) method to high-redshift AGNs (2<z<5) detected with Chandra. This method parametrizes the characteristic 'Compton hump' feature cosmologically redshifted into the X-ray band at observed energies <10 keV. We find good agreement in CT AGNs found using the SC method, and bright sources fit using their full spectrum with X-ray spectroscopy. In the Chandra Deep Field-South, we measure a CT fraction of 17^+19^_-11_% (3/17) for sources with observed luminosity >5x10^43^erg/s. In the Cosmological Evolution Survey (COSMOS), we find an observed CT fraction of 15^+4^_-3_% (40/272) or 32+/-11 per cent when corrected for the survey sensitivity. When comparing to low redshift AGNs with similar X-ray luminosities, our results imply that the CT AGN fraction is consistent with having no redshift evolution. Finally, we provide SC equations that can be used to find high-redshift CT AGNs (z>1) for current (XMM-Newton) and future (eROSITA and ATHENA) X-ray missions.
- ID:
- ivo://CDS.VizieR/J/MNRAS/444/2456
- Title:
- Spectral galaxy pairs from SDSS DR9
- Short Name:
- J/MNRAS/444/2456
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectral galaxy pairs (hereafter as SGPs) are composite galaxy spectra that contain two independent redshift systems. These spectra are useful for studying the dust properties of the foreground galaxies. In this article, a total of 165 spectra of SGPs are mined from the Sloan Digital Sky Survey (SDSS) Data Release 9 (DR9) using the concept of 'membership degree' from fuzzy set theory, especially defined to be suitable for fuzzy identification of emission lines. The spectra and images of this sample are classified according to their membership degree and image features, respectively. Many of the second redshift systems are too small or too dim to select from SDSS images alone, making the sample a potentially unique source of information on dust effects in low-luminosity or low surface brightness galaxies, which are underrepresented in morphological pair samples. The dust extinction of those objects with high membership degree is also estimated by Balmer decrement. Additionally, analyses for a series of spectroscopic observations of one SGP from 165 systems indicate that a newly star-forming region of our Milky Way might exist.