- ID:
- ivo://CDS.VizieR/J/MNRAS/390/741
- Title:
- 150MHz GMRT survey in Eridanus
- Short Name:
- J/MNRAS/390/741
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of a 150MHz survey of a field centred on {epsilon} Eridani, undertaken with the Giant Metrewave Radio Telescope (GMRT). The survey covers an area with a diameter of ~2{deg}, has a spatial resolution of ~30arcsec and a noise level of {sigma}=3.1mJy at the pointing centre. These observations provide a deeper and higher resolution view of the 150MHz radio sky than the 7C survey (although the 7C survey covers a much larger area). A total of 113 sources were detected, most are point-like, but 20 are extended. We present an analysis of these sources, in conjunction with the National Radio Astronomy Observatory (NRAO) Very Large Array (VLA) telescope Sky Survey (NVSS) (at 1.4GHz) and VLA Low-frequency Sky Survey (VLSS) (at 74MHz). This process allowed us to identify five Ultra-Steep Spectrum (USS) radio sources that are candidate high-redshift radio galaxies (HzRGs). In addition, we have derived the dN/dS distribution for these observations and compare our results with other low-frequency radio surveys.
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- 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.
- ID:
- ivo://CDS.VizieR/J/ApJ/804/23
- Title:
- 327MHz observations of 124 pulsars
- Short Name:
- J/ApJ/804/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the measurements of scatter broadening timescales ({tau}_SC_) for 124 pulsars at 327MHz using the upgraded Ooty Radio Telescope (ORT). These pulsars lie in the dispersion measure range of 37-503pc/cm3 and declination ({delta}) range of -57{deg}<{sigma}<60{deg}. New {tau}_SC_ estimates for 58 pulsars are presented, increasing the sample of all such measurements by about 40% at 327MHz. Using all available {tau}_SC_ measurements in the literature, we investigate the dependence of {tau}_SC_ on dispersion measure. Our measurements, together with previously reported values for {tau}_SC_, affirm that the ionized interstellar medium up to 3kpc is consistent with the Kolmogorov spectrum, while it deviates significantly beyond this distance.
- ID:
- ivo://CDS.VizieR/J/MNRAS/376/1251
- Title:
- 610MHz observations of Spitzer XFLS
- Short Name:
- J/MNRAS/376/1251
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations of the Spitzer extragalactic First Look Survey field taken at 610MHz with the Giant Metre-wave Radio Telescope are presented. Seven individual pointings were observed, covering a total area of 4 square degrees with a resolution of 5.8x4.7arcsec^2^, PA=60{deg}. The r.m.s. noise at the centre of the pointings is between 27 and 30uJy before correction for the GMRT primary beam. The techniques used for data reduction and production of a mosaicked image of the region are described, and the final mosaic, along with a catalogue of 3944 sources detected above ~5{sigma} are presented. The survey complements existing radio and infrared data available for this region. For further details of the surveys and data analysis procedures please refer to the published paper.
- ID:
- ivo://CDS.VizieR/J/A+AS/135/273
- Title:
- 408MHz obs. of GPS sources from JVAS survey
- Short Name:
- J/A+AS/135/273
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations with MERLIN at 408 MHz have been used to establish the low-frequency part of the spectra of more than a hundred compact radio sources taken from the part of the Jodrell Bank-VLA Astrometric Survey (JVAS) limited by 35{deg}<={delta}<=75{deg}. These sources were selected from JVAS and other catalogues to have convex spectra between 1.4 and 8.4GHz, characteristic of Gigahertz Peaked Spectrum sources. We have confirmed convex shapes of the spectra of 76 objects.
- ID:
- ivo://CDS.VizieR/J/A+AS/90/327
- Title:
- 1612MHz OH survey of IRAS point sources
- Short Name:
- J/A+AS/90/327
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 2703 sources have been observed at the 1612MHz transition of OH, and 783 OH/IR stars were detected; 597 of these detections are new discoveries. The IRAS sources were detected on the basis of their IRAS fluxes at 12, 25 and 60um. The survey is 70% complete for IRAS sources in the Southern hemisphere (Dec<-10{deg}) with F(12um)>3Jy, with IR colors log(F25/F12)>-0.2 and log(F60/F12)<0.6 Note that the file catalog.dat contains all observed sources, with a flag indicating the detection or non-detection; the detected sources only are listed in the printed version of Table2, while sources without detectable 1612MHz emission are listed in Table3 (on microfiche)
- ID:
- ivo://CDS.VizieR/J/ApJS/155/89
- Title:
- 325MHz radio survey in M31
- Short Name:
- J/ApJS/155/89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present here the results of a 325MHz radio survey of M31, conducted with the A configuration of the Very Large Array. The survey covered an area of 7.6{deg}^2^, and a total of 405 radio sources between <~6" and 170" in extent were mapped with a resolution of 6" and a 1{sigma} sensitivity of ~0.6mJy/beam. For each source, its morphological class, major axis {theta}_M_, minor axis {theta}_m_, position angle {theta}_PA_, peak flux I, integrated flux density S, spectral index {alpha}, and spectral curvature parameter {phi} were calculated.
- ID:
- ivo://CDS.VizieR/J/ApJS/159/242
- Title:
- 325MHz radio survey in M31. II.
- Short Name:
- J/ApJS/159/242
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have previously presented the results of a 325MHz radio survey of M31 (Cat. <J/ApJS/155/89>, conducted with the A configuration of the Very Large Array. In this survey, a total of 405 radio sources between <~6" and 170" in extent were mapped with a resolution of 6" and a sensitivity of ~0.6mJy/beam. Here we compare the resultant source list and image with other radio, IR, optical, and X-ray observations and catalogs of the region.
- ID:
- ivo://CDS.VizieR/J/ApJ/846/L19
- Title:
- 115-155MHz radio survey of Fermi sources
- Short Name:
- J/ApJ/846/L19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using LOFAR, we have performed a very-low-frequency (115-155MHz) radio survey for millisecond pulsars (MSPs). The survey targeted 52 unidentified Fermi {gamma}-ray sources. Employing a combination of coherent and incoherent dedispersion, we have mitigated the dispersive effects of the interstellar medium while maintaining sensitivity to fast-spinning pulsars. Toward 3FGLJ1553.1+5437 we have found PSRJ1552+5437, the first MSP to be discovered (through its pulsations) at a radio frequency <200MHz. PSR J1552+5437 is an isolated MSP with a 2.43ms spin period and a dispersion measure of 22.9pc/cm^3^. The pulsar has a very steep radio spectral index ({alpha}-2.8+/-0.4). We obtain a phase-connected timing solution combining the 0.74yr of radio observations with {gamma}-ray photon arrival times covering 7.5yr of Fermi observations. We find that the radio and {gamma}-ray pulse profiles of PSR J1552+5437 appear to be nearly aligned. The very steep spectrum of PSR J1552+5437, along with other recent discoveries, hints at a population of radio MSPs that have been missed in surveys using higher observing frequencies. Detecting such steep spectrum sources is important for mapping the population of MSPs down to the shortest spin periods, understanding their emission in comparison to slow pulsars, and quantifying the prospects for future surveys with low-frequency radio telescopes like SKA-Low and its precursors.