- ID:
- ivo://CDS.VizieR/J/MNRAS/298/637
- Title:
- 7C: 151MHz survey of 3 regions
- Short Name:
- J/MNRAS/298/637
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Cambridge Low Frequency Synthesis Telescope has been used at 151MHz to survey three regions centred at RA=10h05min, DE=53{deg}54', RA=10h42min, DE=57{deg}36' and RA=13h32min, DE=38{deg}10', each of area 7.3x7.3cosec(DE)deg^2^. The resolution is 70x70cosec(DE)arcsec^2^, and the rms noise on the maps is typically 15mJy/beam. We present positions and flux densities for 2381 sources which have signal-to-noise ratios >5.5.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/581/A48
- Title:
- 1.3cm line survey toward Orion KL
- Short Name:
- J/A+A/581/A48
- Date:
- 18 Nov 2021 11:23:37
- Publisher:
- CDS
- Description:
- Orion KL has served as a benchmark for spectral line searches throughout the (sub)millimeter regime. The main goal is to systematically study spectral characteristics of Orion KL in the 1.3cm band. We carried out a spectral line survey (17.9GHz to 26.2GHz) with the Effelsberg-100m telescope towards Orion KL. We find 261 spectral lines, yielding an average line density of about 32 spectral features per GHz above 3 sigma. The identified lines include 164 radio recombination lines (RRLs) and 97 molecular lines. A total of 23 molecular transitions from species known to exist in Orion KL are detected for the first time in the interstellar medium. Non-metastable ^15^NH_3_ transitions are detected in Orion KL for the first time. Based on the velocity information of detected lines and the ALMA images, the spatial origins of molecular emission are constrained and discussed. A narrow feature is found in SO_2_ (8_1,7_-7_2,6_), possibly suggesting the presence of a maser line. Column densities and fractional abundances relative to H_2_ are estimated for 12 molecules with LTE methods. Rotational diagrams of non-metastable ^14^NH_3_ transitions with J=K+1 to J=K+4 yield different results; metastable ^15^NH_3_ is found to have a higher excitation temperature than non-metastable ^15^NH_3_, indicating that they may trace different regions. Elemental and isotopic abundance ratios are estimated: ^12^C/^13^C=63+/-17, ^14^N/^15^N=100+/-51, D/H=0.0083+/-0.0045. The dispersion of the He/H ratios derived from H_alpha/He_alpha_ pairs to H_delta_/He_delta_ pairs is very small, which is consistent with theoretical predictions that the departure coefficients bn factors for hydrogen and helium are nearly identical. Based on a non-LTE code neglecting excitation by the infrared radiation field and a likelihood analysis, we find that the denser regions have lower kinetic temperature, which favors an external heating of the Hot Core.
- ID:
- ivo://CDS.VizieR/J/AJ/136/1889
- Title:
- 20cm observations of deep Swire Field
- Short Name:
- J/AJ/136/1889
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from deep radio observations taken with the Very Large Array at a center frequency of 1400MHz covering a region of the Spitzer Wide-area InfraRed Extragalactic Survey of the Spitzer Legacy survey, centered at 10:46:00, +59:01:00 (J2000). The reduction and cataloging of radio sources are described. An electronic catalog of the sources detected above 5{sigma} is also presented. The survey presented is the deepest so far in terms of the radio source density on the sky. Perhaps surprisingly, the sources down to the bottom of the catalog appear to have median angular sizes still greater than 1-arcsec, like their cousins 10-100 times stronger. The shape of the differential logN-logS counts also seems to require a correction for the finite sizes of the sources to be self-consistent. If the logN-logS normalization remains constant at the lowest flux densities, there are about six sources per square arcminute at 15uJy at 20cm. Given the finite-source size this implies that we may reach the natural confusion limit near 1uJy.
- ID:
- ivo://CDS.VizieR/J/AJ/137/4846
- Title:
- 90cm observations of the deep SWIRE field
- Short Name:
- J/AJ/137/4846
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present one of the deepest radio continuum surveys to date at a wavelength >~1m. The observations were taken with the VLA at 324.5MHz covering a region of the SWIRE Spitzer Legacy survey, centered at 10:46:00, +59:01:00 (J2000). The data reduction and analysis are described and an electronic catalog of the sources detected above 5{sigma} is presented. We also discuss the observed angular size distribution for the sample. Using our deeper 20cm survey of the same field, we calculate spectral indices for sources detected in both surveys.
- ID:
- ivo://CDS.VizieR/J/A+A/517/A54
- Title:
- 20cm survey of the AKARI NEP
- Short Name:
- J/A+A/517/A54
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Westerbork Radio Synthesis Telescope, WSRT, has been used to make a deep radio survey of an ~1.7degree^2^ field coinciding with the AKARI north ecliptic pole deep field. The observations, data reduction and source count analysis are presented, along with a description of the overall scientific objectives. The survey consisted of 10 pointings, mosaiced with enough overlap to maintain a similar sensitivity across the central region that reached as low as 21uJy/beam at 1.4GHz.
- ID:
- ivo://CDS.VizieR/J/MNRAS/427/1830
- Title:
- 20cm survey of the AKARI SEP (ATCA-ADFS)
- Short Name:
- J/MNRAS/427/1830
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of a deep radio survey at 20cm wavelength are reported for a region containing the AKARI Deep Field South (ADF-S) near the South Ecliptic Pole (SEP), using the Australia Telescope Compact Array (ATCA). The survey (hereafter referred to as the ATCA-ADFS survey) has 1{sigma} detection limits ranging from 18.7 to 50{mu}Jy/beam over an area of ~1.1deg^2^, and ~ 2.5deg^2^ to lower sensitivity. The observations, data reduction and source count analysis are presented along with a description of the overall scientific objectives, and a catalogue containing 530 radio sources detected with a resolution of 6.2x4.9arcsec.
- ID:
- ivo://CDS.VizieR/J/ApJS/154/673
- Title:
- COBE DIRBE Point Source Catalog
- Short Name:
- J/ApJS/154/673
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the COBE DIRBE Point Source Catalog, an all-sky catalog containing infrared photometry in 10 bands from 1.25 microns to 240 microns for 11788 of the brightest near and mid-infrared point sources in the sky. Since DIRBE had excellent temporal coverage (100-1900 independent measurements per object during the 10 month cryogenic mission), the Catalog also contains information about variability at each wavelength, including amplitudes of variation observed during the mission. Since the DIRBE spatial resolution is relatively poor (0.7{deg}), we have carefully investigated the question of confusion, and have flagged sources with infrared-bright companions within the DIRBE beam. In addition, we filtered the DIRBE light curves for data points affected by companions outside of the main DIRBE beam but within the `sky' portion of the scan. At high Galactic latitudes (|b|>5{deg}), the Catalog contains essentially all of the unconfused sources with flux densities greater than 90, 60, 60, 50, 90, and 165 Jy at 1.25, 2.2, 3.5, 4.9, 12, and 25 microns, respectively, corresponding to magnitude limits of approximately 3.1, 2.6, 1.7, 1.3, -1.3, and -3.5. At longer wavelengths and in the Galactic Plane, the completeness is less certain because of the large DIRBE beam and possible contributions from extended emission. The Catalog also contains the names of the sources in other catalogs, their spectral types, variability types, and whether or not the sources are known OH/IR stars. We discuss a few remarkable objects in the Catalog.
- ID:
- ivo://CDS.VizieR/J/ApJ/878/44
- Title:
- ^13^CO clumps toward the Cassiopeia A supernova remnant
- Short Name:
- J/ApJ/878/44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted a large-field simultaneous survey of ^12^CO, ^13^CO, and C^18^O J=1-0 emission toward the Cassiopeia A (Cas A) supernova remnant (SNR), which covers a sky area of 3.5{deg}x3.1{deg}. The Cas giant molecular cloud (GMC) mainly consists of three individual clouds with masses on the order of 10^4^-10^5^M_{sun}_. The total mass derived from the ^13^CO emission of the GMC is 2.1x10^5^M_{sun}_ and is 9.5x10^5^M_{sun}_ from the ^12^CO emission. Two regions with broadened (6-7km/s) or asymmetric ^12^CO line profiles are found in the vicinity (within a 10'x10' region) of the Cas A SNR, indicating possible interactions between the SNR and the GMC. Using the GAUSSCLUMPS algorithm, 547 ^13^CO clumps are identified in the GMC, 54% of which are supercritical (i.e., {alpha}_vir_<2). The mass spectrum of the molecular clumps follows a power-law distribution with an exponent of -2.20. The pixel-by-pixel column density of the GMC can be fitted with a log-normal probability distribution function (N-PDF). The median column density of molecular hydrogen in the GMC is 1.6x10^21^cm^-2^ and half the mass of the GMC is contained in regions with H_2_ column density lower than 3x10^21^cm^-2^, which is well below the threshold of star formation. The distribution of the YSO candidates in the region shows no agglomeration.
- ID:
- ivo://CDS.VizieR/J/A+A/638/A114
- Title:
- CODEX galaxy clusters catalog
- Short Name:
- J/A+A/638/A114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Large area catalogs of galaxy clusters constructed from ROSAT All Sky Survey provide the base for our knowledge on the population of clusters thanks to the long-term multiwavelength efforts to follow-up observations of these clusters.. Advent of large area photometric surveys superseding in depth previous all-sky data allows us to revisit the construction of X-ray cluster catalogs, extending the study to lower cluster masses and to higher redshifts and to provide the modelling of the selection function. We perform a wavelet detection of X-ray sources and make extensive simulations of the detection of clusters in the RASS data. We assign an optical richness to each of the 24,788 detected X-ray sources in the 10,382 square degrees of SDSS BOSS area, using redMaPPer version 5.2 run on Sloan Digital Sky Survey photometry. We name this survey COnstrain Dark Energy with X-ray (CODEX) clusters. We show that there is no obvious separation of sources on galaxy clusters and AGN, based on distribution of systems on their richness. This is a combination of increasing number of galaxy groups and their selection as identification of an X-ray sources either by chance or due to groups hosting an AGN. To clean the sample, we use a cut on the optical richness at the level corresponding to the 10% completeness of the survey and include it into the modelling of cluster selection function. We present the X-ray catalog extending to a redshift of 0.6. CODEX is the first large area X-ray selected catalog of Northern clusters reaching the fluxes of 10^-13^ergs/s/cm^2^. We provide the modelling of the sample selection and discuss the redshift evolution of the high end of the X-ray luminosity function (XLF). Our results on z<0.3 XLF are in agreement with previous studies, while we provide new constraints on the 0.3<z<0.6 XLF. We find a lack of strong redshift evolution of the XLF, provide exact modeling of the effect of low number statistics and AGN contamination and present the resulting constraints on the flat {LAMBDA}CDM.
- ID:
- ivo://CDS.VizieR/J/ApJ/860/174
- Title:
- CO in Protostars (COPS): Herschel spectroscopy
- Short Name:
- J/ApJ/860/174
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present full spectral scans from 200 to 670{mu}m of 26 Class 0+I protostellar sources obtained with Herschel-SPIRE as part of the "COPS-SPIRE" Open Time program, complementary to the DIGIT and WISH Key Programs. Based on our nearly continuous, line-free spectra from 200 to 670{mu}m, the calculated bolometric luminosities (Lbol) increase by 50% on average, and the bolometric temperatures (Tbol) decrease by 10% on average, in comparison with the measurements without Herschel. Fifteen protostars have the same class using Tbol and Lbol/Lsmm. We identify rotational transitions of CO lines from J=4->3 to J=13->12, along with emission lines of ^13^CO, HCO^+^, H_2_O, and [CI]. The ratios of ^12^CO to ^13^CO indicate that ^12^CO emission remains optically thick for J_up_<13. We fit up to four components of temperature from the rotational diagram with flexible break points to separate the components. The distribution of rotational temperatures shows a primary population around 100K with a secondary population at ~350K. We quantify the correlations of each line pair found in our data set and find that the strength of the correlation of CO lines decreases as the difference between J levels between two CO lines increases. The multiple origins of CO emission previously revealed by velocity-resolved profiles are consistent with this smooth distribution if each physical component contributes to a wide range of CO lines with significant overlap in the CO ladder. We investigate the spatial extent of CO emission and find that the morphology is more centrally peaked and less bipolar at high-J lines. We find the CO emission observed with SPIRE related to outflows, which consists of two components, the entrained gas and shocked gas, as revealed by our rotational diagram analysis, as well as the studies with velocity-resolved CO emission.
