- ID:
- ivo://CDS.VizieR/J/MNRAS/402/803
- Title:
- M31 globular cluster system
- Short Name:
- J/MNRAS/402/803
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an updated catalogue of M31 globular clusters (GCs) based on images from the Wide Field Camera (WFCAM) on the United Kingdom Infrared Telescope and from the Sloan Digital Sky Survey (SDSS). Our catalogue includes new, self-consistent ugriz and K-band photometry of these clusters. We discuss the difficulty of obtaining accurate photometry of clusters projected against M31 due to small-scale background structure in the galaxy. We consider the effect of this on the accuracy of our photometry and provide realistic photometric error estimates. We investigate possible contamination in the current M31 GC catalogues using the excellent spatial resolution of these WFCAM images combined with the SDSS multicolour photometry. We identify a large population of clusters with very blue colours. Most of these have recently been proposed by other works as young clusters. We distinguish between these, and old clusters, in the final classifications. Our final catalogue includes 416 old clusters, 156 young clusters and 373 candidate clusters. We also investigate the structure of M31's old GCs using previously published King model fits to these WFCAM images. We demonstrate that the structure and colours of M31's old GC system are similar to those of the Milky Way. One GC (B383) is found to be significantly brighter in previous observations than observed here. We investigate all of the previous photometry of this GC and suggest that this variability appears to be genuine and short lived. We propose that the large increase in its luminosity may have been due to a classical nova in the GC at the time of the previous observations in 1989.
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2282. M31 Herschel images
- ID:
- ivo://CDS.VizieR/J/A+A/567/A71
- Title:
- M31 Herschel images
- Short Name:
- J/A+A/567/A71
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dust and stars play a complex game of interactions in the interstellar medium and around young stars. The imprints of these processes are visible in scaling relations between stellar characteristics, star formation parameters, and dust properties. Aims. In the present work, we aim to examine dust scaling relations on a sub-kpc resolution in the Andromeda galaxy (M31). The goal is to investigate the properties of M31 on both a global and local scale and compare them to other galaxies of the local universe. Methods. New Herschel observations are combined with available data from GALEX, SDSS, WISE, and Spitzer to construct a dataset covering UV to submm wavelengths. All images were brought to the beam size and pixel grid of the SPIRE 500um frame. This divides M31 in 22437 pixels of 36 arcseconds in size on the sky, corresponding to physical regions of 137x608pc in the galaxy's disk. A panchromatic spectral energy distribution was modelled for each pixel and maps of the physical quantities were constructed. Several scaling relations were investigated, focussing on the interactions of dust with starlight. Results. We find, on a sub-kpc scale, strong correlations between Mdust/M* and NUV-r, and between Mdust/M* and mu* (the stellar mass surface density). Striking similarities with corresponding relations based on integrated galaxies are found. We decompose M31 in four macro-regions based on their FIR morphology; the bulge, inner disk, star forming ring, and the outer disk region. In the scaling relations, all regions closely follow the galaxy-scale average trends and behave like galaxies of different morphological types. The specific star formation characteristics we derive for these macro-regions give strong hints of an inside-out formation of the bulge-disk geometry, as well as an internal downsizing process. Within each macro-region, however, a great diversity in individual micro-regions is found, regardless of the properties of the macro-regions. Furthermore, we confirm that dust in the bulge of M31 is heated only by the old stellar populations. Conclusions. In general, the local dust scaling relations indicate that the dust content in M31 is maintained by a subtle interplay of past and present star formation. The similarity with galaxy-based relations strongly suggests that they are in situ correlations, with underlying processes that must be local in nature.
- ID:
- ivo://CDS.VizieR/J/MNRAS/435/650
- Title:
- 325MHz GMRT survey of Herschel-ATLAS/GAMA fields
- Short Name:
- J/MNRAS/435/650
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe a 325MHz survey, undertaken with the Giant Metrewave Radio Telescope (GMRT), which covers a large part of the three equatorial fields at 9, 12 and 14.5h of right ascension from the Herschel-Astrophysical Terahertz Large Area Survey (H-ATLAS) in the area also covered by the Galaxy And Mass Assembly (GAMA) survey. The full data set, after some observed pointings were removed during the data reduction process, comprises 212 GMRT pointings covering ~90deg^2^ of sky. We have imaged and catalogued the data using a pipeline that automates the process of flagging, calibration, self-calibration and source detection for each of the survey pointings. The resulting images have resolutions of between 14 and 24-arcsec and minimum rms noise (away from bright sources) of ~1mJy/beam, and the catalogue contains 5263 sources brighter than 5{sigma}. We investigate the spectral indices of GMRT sources which are also detected at 1.4GHz and find them to agree broadly with previously published results; there is no evidence for any flattening of the radio spectral index below S_1.4_=10mJy. This work adds to the large amount of available optical and infrared data in the H-ATLAS equatorial fields and will facilitate further study of the low-frequency radio properties of star formation and AGN activity in galaxies out to z~1.
- ID:
- ivo://CDS.VizieR/J/MNRAS/421/1644
- Title:
- 843MHz MOST ATLAS catalogue
- Short Name:
- J/MNRAS/421/1644
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- At the faintest radio flux densities (S1.4<10mJy), conflicting results have arisen regarding whether there is a flattening of the average spectral index between a low radio frequency (325 or 610MHz) and, for example, 1.4GHz. We present a new catalogue of 843-MHz radio sources in the European Large Area ISO Survey-South 1 field, which contains the sources, their Australia Telescope Large Area Survey (ATLAS) counterparts and the spectral index distribution of the sources as a function of flux density.
- ID:
- ivo://CDS.VizieR/VIII/98
- Title:
- 180MHz Murchison Commissioning Survey (MWACS)
- Short Name:
- VIII/98
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Murchison Widefield Array Commissioning Survey (MWACS) is a ~6100deg^2^ 104-196MHz radio sky survey performed with the Murchison Widefield Array during instrument commissioning between 2012 September and 2012 December. The data were taken as meridian drift scans with two different 32-antenna sub-arrays that were available during the commissioning period. The data were combined in the visibility plane before being imaged, and then mosaicked. The survey covers approximately 20.5h<RA<8.5h, -58{deg}<Dec<-14{deg} over three frequency bands centred on 119, 150 and 180MHz. The survey has 3arcmin angular resolution and a typical noise level of 40mJy/beam, with reduced sensitivity near the field boundaries and bright sources. The catalogue consists of flux density and spectral index measurements for 14,110 sources, extracted from the mosaics, 1,247 of which are sub-components of complexes of sources.
2286. 408MHz observations
- ID:
- ivo://CDS.VizieR/J/A+AS/120/89
- Title:
- 408MHz observations
- Short Name:
- J/A+AS/120/89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the second paper based on the 408MHz monitoring program with the East-West arm of the Bologna interferometer. The monitoring concerned 125 radio sources measured approximately once a month for 15 years. We present the summary of the variability analysis concerning all the sample and the monitoring data, not yet published, of the variable sources.
- ID:
- ivo://CDS.VizieR/J/A+A/656/A137
- Title:
- 144MHz radio fluxes of z>5 quasars
- Short Name:
- J/A+A/656/A137
- Date:
- 17 Mar 2022 14:39:39
- Publisher:
- CDS
- Description:
- Optically luminous quasars at z>5 are important probes of super-massive black hole (SMBH) formation. With new and future radio facilities, the discovery of the brightest low-frequency radio sources in this epoch would be an important new probe of cosmic reionization through 21-cm absorption experiments. We present the result of a study of the low-frequency radio properties of a sample of 115 known spectroscopically confirmed z>5 quasars using the second data release of the Low Frequency Array (LOFAR) Two Meter Sky survey (LoTSS-DR2), reaching noise levels of 80uJy/beam (at 144MHz) over an area of 5720 square degrees. We find that 41 sources (36%) are detected in LoTSS-DR2 at >2{sigma} significance and we explore the evolution of their radio properties (power, spectral index, and radio loudness) as a function of redshift and rest-frame ultra-violet properties.
- ID:
- ivo://CDS.VizieR/J/A+AS/97/435
- Title:
- 1410MHz-spectra of quasars III.
- Short Name:
- J/A+AS/97/435
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the third and final part of the research at 1410MHz for 213 extragalactic objects from the Southern Hemisphere identified as Quasars by Veron-Cetty and Veron (1983A&AS...53..219V). The first (1988A&AS...76...21Q) and second (1990A&AS...83..393Q) parts contained measurement of the flux densities at 1410MHz for 473 sources.
- ID:
- ivo://CDS.VizieR/VIII/29A
- Title:
- 1400-MHz Survey of 1478 Abell Clusters of Galaxies
- Short Name:
- VIII/29A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains observations of Abell clusters of galaxies which were obtained with the Green Bank 91-m telescope at 1400 MHz with an angular resolution of 10'x11' (RAxDEC). This catalog extends the sample of clusters originally published in Owen (1974AJ.....79..427O). The primary goals of this survey were to observe all Abell (1958ApJS....3..211A, Cat. VII/4) clusters with m10 (magnitude of the tenth brightest galaxy in the cluster) less than or equal to 17.0 and declinations north of -19 degrees, to observe all clusters with richness>=3 regardless of m10, and to obtain observations of a representative sample of the rest of the catalog (m10>=17.0; richness<=2). The abelclus.dat file contains ALL 957 detected sources (also beyond 0.5 corrected Abell radii). It contains 525 sources within 0.5 corrected Abell radii, while the published table1.dat file contains 487 entries corresponding to 485 distinct sources (in 442 clusters). The catalog entries contains the flux density at 1400 MHz, the Abell cluster number, richness class, distance class, m10, redshift estimate (z), corrected Abell cluster radius, right ascension (B1950), declination (B1950), deconvolved major and minor source axis lengths, position angle, and distance of the source from the cluster center.
- ID:
- ivo://CDS.VizieR/J/A+AS/41/151
- Title:
- 1415MHz Survey of Bright Galaxies
- Short Name:
- J/A+AS/41/151
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The radio continuum radiation at 1415MHz of 450 galaxies was observed with the Westerbork Synthesis Radio Telescope. 190 galaxies were detected. The survey provides data on the total intensity and on the structure of the radiation. The detection limit for point sources is 10mJy and the resolution is about 23" on average.