- ID:
- ivo://CDS.VizieR/J/ApJ/792/L2
- Title:
- C/2012 F6 (Lemmon) and C/2012 S1 (ISON) maps
- Short Name:
- J/ApJ/792/L2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results are presented from the first cometary observations using the Atacama Large Millimeter/Submillimeter Array (ALMA), including measurements of the spatially resolved distributions of HCN, HNC, H_2_CO, and dust within the comae of two comets: C/2012 F6 (Lemmon) and C/2012 S1 (ISON), observed at heliocentric distances of 1.5 AU and 0.54 AU, respectively. These observations (with angular resolution ~0.5"), reveal an unprecedented level of detail in the distributions of these fundamental cometary molecules, and demonstrate the power of ALMA for quantitative measurements of the distributions of molecules and dust in the inner comae of typical bright comets. In both comets, HCN is found to originate from (or within a few hundred kilometers of) the nucleus, with a spatial distribution largely consistent with spherically symmetric, uniform outflow. By contrast, the HNC distributions are clumpy and asymmetrical, with peaks at cometocentric radii ~500-1000km, consistent with release of HNC in collimated outflow(s). Compared to HCN, the H_2_ CO distribution in comet Lemmon is very extended. The interferometric visibility amplitudes are consistent with coma production of H_2_CO and HNC from unidentified precursor material(s) in both comets. Adopting a Haser model, the H_2_CO parent scale length is found to be a few thousand kilometers in Lemmon and only a few hundred kilometers in ISON, consistent with the destruction of the precursor by photolysis or thermal degradation at a rate that scales in proportion to the solar radiation flux.
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- ID:
- ivo://CDS.VizieR/J/ApJ/455/60
- Title:
- CFRS II: 0000-00 and 1000+25 fields
- Short Name:
- J/ApJ/455/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper describes the methods used to obtain the spectroscopic data and construct redshift catalogs for the Canada-France Deep Redshift Survey (CFRS). The full data set consists of more than 1000 spectra, of objects with 17.5=<I_AB_=<22.5, obtained from deep multislit data with the MARLIN and MOS-SIS spectrographs at the Canada-France-Hawaii Telescope (CFHT). The final spectroscopic catalog contains 200 stars, 591 galaxies with secure redshifts in the range 0=<z=<1.3, six QSOs, and 146 objects with very uncertain or unknown redshifts, leading to an overall success rate of identification of 85%. In addition, 67 objects affected by observational problems have been placed in a supplemental list. We describe here the instrumental setup and the observing procedures used to gather this large data set efficiently. New optimal ways of packing spectra on the detector to increase significantly the multiplexing gain offered by multislit spectroscopy are described. Dedicated data reduction procedures have been developed under the IRAF environment to allow for fast and accurate processing. Very strict procedures have been followed to establish a reliable list of final spectroscopic measurements. Fully independent processing of the data has been carried out by three members of the team for each data set associated with a multislit mask, and final redshifts were assigned only after the careful comparison of the three independent measurements. A confidence class scheme was established. We strongly emphasize the benefits of such procedures. Finally, we present the spectroscopic data obtained for 303 objects in the 0000-00 and 1000+25 fields. The success rate in spectroscopic identification is 83% for the 0000-00 field and 84% for the 1000+25 field.
- ID:
- ivo://CDS.VizieR/J/ApJ/455/75
- Title:
- CFRS III: 1415+52 and 2215+00 fields
- Short Name:
- J/ApJ/455/75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is one of a series describing the Canada-France Redshift Survey (CFRS). It is shown how the shape of the continuum around the emission line can be used to distinguish between [O II]{lambda}3727 at z>0.76 and H{alpha} at low redshift in spectra for which only a single isolated emission line is visible. Based on this, [O II]{lambda}3727 is most likely to be the emission line in most of the single emission-line galaxies in the CFRS. The statistics of the repeated observations are analyzed to derive an empirical calibration of the reliability of the spectroscopic identifications in the CFRS in order to determine how often additional observations could lead to the identification of an initially unidentified object and to provide an estimate of the internal velocity accuracy. Finally, the results of spectroscopic observations of 413 objects in the 1415+52 and 2215+00 CFRS survey fields are presented.
3034. CFRS IV: 0300+00 field
- ID:
- ivo://CDS.VizieR/J/ApJ/455/88
- Title:
- CFRS IV: 0300+00 field
- Short Name:
- J/ApJ/455/88
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Possible surface brightness selection effects in the redshift catalogs of the Canada-France Redshift Survey are investigated through comparisons of subsamples of the data. Our analyses demonstrate that the securing of redshifts is independent of possible biases arising from surface brightness effects and/or differing galaxy morphologies and orientations. The unusual geometry of the mask designs for our spectroscopic observations also do not produce any significant bias. There is, however, a bias at the highest and lowest redshifts, especially for absorption-line galaxies at z>1 and z<0.2, due to the adopted spectral range (4250-8500A). Apart from the latter, we conclude that our sample of identified galaxies is an unbiased subsample of the original photometric catalog and is essentially limited by I-band flux density (17.5<I_AB_<22.5). Finally, spectroscopic data for the remaining CFRS field is presented. Data for 272 objects in the 0300+0000 field are given.
- ID:
- ivo://CDS.VizieR/J/ApJ/464/79
- Title:
- CFRS XI: High-redshift field galaxies morphology
- Short Name:
- J/ApJ/464/79
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 143 galaxies with secure redshifts (Z_median_=0.62) from the 1415+52 field of the Canada-France Redshift Survey have been imaged with median seeing of 0.67" (FWHM). Structural parameters have been derived by fitting multicomponent models and the results confirm two phenomena seen in a smaller sample of galaxies imaged with the Hubble Space Telescope. First, 11+/-3% of the galaxies lie off the normal locus of color versus bulge fraction B/T. This class of objects ("blue nucleated galaxies," or BNGs) was identified using HST observations (Schade et al. 1995ApJ...451L...1S, hereafter CFRS IX), and it was shown that they are associated with peculiar/asymmetric structure and merger/interactions. The observed frequency of BNGs in this sample is 14+/-4% 0.5<z<1.2 and 6^+6^_-3_% at 0.2<z<0.5, but the true frequency is likely to be a factor ~2 higher after corrections are made for the effect of asymmetric/peculiar structures. Galaxy disks at 0.5<z<1.1 are found to have a mean rest-frame, inclination-corrected central surface brightness of {mu}_AB_(B)=19.8+/-0.1mag/arcsec^2^, ~1.6mag brighter than the Freeman (1970ApJ...160..811F) value. At low redshift (0.2<z<0.5) the mean surface brightness [{mu}_AB_(B)=21.3+/-0.25] is consistent with the Freeman value. These results are consistent with the HST observations. With larger numbers of galaxies and therefore more statistical weight they demonstrate the capabilities, and limits, of ground-based work in the study of galaxy morphology at high redshift.
- ID:
- ivo://CDS.VizieR/J/ApJ/481/49
- Title:
- CFRS XIV. Field galaxies up to z=1
- Short Name:
- J/ApJ/481/49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The spectral properties of more than 400 Canada-France Redshift Survey (CFRS) galaxies and their changes over the redshift interval 0<=z<=1.3 are investigated. Emission-line intensities and equivalent widths for accessible lines have been measured, as well as continuum color indices based on 200{AA} wide spectral regions.
- ID:
- ivo://CDS.VizieR/J/A+A/420/595
- Title:
- CG Cygni light variations
- Short Name:
- J/A+A/420/595
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report new photometry of CG Cyg from 1998-2002. We also analyze published photometry collected since 1965. ************************************************************************** * * * Sorry, but the author(s) never supplied the tabular material * * announced in the paper * * * **************************************************************************
- ID:
- ivo://CDS.VizieR/J/MNRAS/294/607
- Title:
- 7C(G) 151MHz survey of the Galactic plane
- Short Name:
- J/MNRAS/294/607
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results form a survey of the northern Galactic plane (at declination >=30{deg} at 151MHz made with the Cambridge Low Frequency Synthesis Telescope are presented. This survey is designated 7C(G) - i.e. the Galactic portion of the ongoing 7C surveys. This covers the regions 80{deg}<l<104{deg} and 126{deg}<l<180{deg}, for |b|<=5.5{deg}, and has some coverage to |b|~9{deg}, with a resolution of ~70x70cosec{delta}arcsec^2^ (RAxDec). The observations, data reduction and calibration of this survey are described, and a catalogue of 6262 compact sources, with a completeness limit of ~0.25Jy over most of the survey region, is presented. The catalogue has an rms positional accuracy of better than 10arcsec, and the flux densities are tied to the scale of Roger, Bridle & Costain (1973AJ.....78.1030R) with an accuracy of better than 10 per cent.
- ID:
- ivo://CDS.VizieR/J/ApJS/233/20
- Title:
- CGM-MASS. II. New XMM data for 6 spirals
- Short Name:
- J/ApJS/233/20
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the analysis of the XMM-Newton data of the Circum-Galactic Medium of MASsive Spirals (CGM-MASS) sample of six extremely massive spiral galaxies in the local universe. All the CGM-MASS galaxies have diffuse X-ray emission from hot gas detected above the background extending ~(30-100)kpc from the galactic center. This doubles the existing detection of such extended hot CGM around massive spiral galaxies. The radial soft X-ray intensity profile of hot gas can be fitted with a {beta}-function, with the slope typically in the range of {beta}=0.35-0.55. This range, as well as those {beta} values measured for other massive spiral galaxies, including the Milky Way (MW), are in general consistent with X-ray luminous elliptical galaxies of similar hot gas luminosity and temperature, and with those predicted from a hydrostatic- isothermal gaseous halo. Hot gas in such a massive spiral galaxy tends to have temperature comparable to its virial value, indicating the importance of gravitational heating. This is in contrast to lower mass galaxies, where hot gas temperature tends to be systematically higher than the virial one. The ratio of the radiative cooling to free fall timescales of hot gas is much larger than the critical value of ~10 throughout the entire halos of all the CGM-MASS galaxies, indicating the inefficiency of gas cooling and precipitation in the CGM. The hot CGM in these massive spiral galaxies is thus most likely in a hydrostatic state, with the feedback material mixed with the CGM, instead of escaping out of the halo or falling back to the disk. We also homogenize and compare the halo X-ray luminosity measured for the CGM-MASS galaxies and other galaxy samples and discuss the "missing" galactic feedback detected in these massive spiral galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJS/175/97
- Title:
- CGRaBS: survey of {gamma}-ray blazar candidates
- Short Name:
- J/ApJS/175/97
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe a uniform all-sky survey of bright blazars, selected primarily by their flat radio spectra, that is designed to provide a large catalog of likely {gamma}-ray active galactic nuclei (AGNs). The defined sample has 1625 targets with radio and X-ray properties similar to those of the EGRET blazars, spread uniformly across the |^b^|>10{deg} sky. We also report progress toward optical characterization of the sample; of objects with known R<23, 85% have been classified and 81% have measured redshifts. One goal of this program is to focus attention on the most interesting (e.g., high-redshift, high-luminosity, ...) sources for intensive multiwavelength study during the observations by the Large Area Telescope (LAT) on GLAST.