- ID:
- ivo://CDS.VizieR/J/ApJ/655/958
- Title:
- 90-GHz observations in NGC 1333
- Short Name:
- J/ApJ/655/958
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We observed the clustered star forming complex NGC 1333 with the BIMA and FCRAO telescopes in the transitions HCO+(1-0) and N_2_H+(1-0) over an area with resolution ~10" (0.015pc). The N_2_H+ emission follows very closely the submillimeter dust continuum emission, while HCO+ emission appears more spatially extended and also traces outflows. We have identified 93 N_2_H+ cores using the CLUMPFIND algorithm, and we derive N_2_H+ core masses between 0.05 and 2.5M_{sun}_ , with uncertainties of a factor of a few, dominated by the adopted N_2_H+ abundance.
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- ID:
- ivo://CDS.VizieR/J/ApJS/51/67
- Title:
- 5 GHz Observations of Arecibo 611 MHz Sources
- Short Name:
- J/ApJS/51/67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Arecibo 611 MHz survey of Durdin et al. (1975) listed 3118 radio sources stronger than 0.35 Jy in the region -3d to +19d and 22h to 13h. Of these sources, 2911 have been observed using the NRAO 300 foot transit telescope at 4755 MHz. Positions, fluxes, and spectral indices are given for the 2661 detected sources. The beamwidth of the 300 foot telescope is nominally 2.8 arcmin FWHM at 6 cm, compared to the 12 arcmin beamwidth of the Arecibo survey, allowing a significant improvement in source positions.
- ID:
- ivo://CDS.VizieR/J/AJ/133/1947
- Title:
- 37GHz observations of BL Lac objects
- Short Name:
- J/AJ/133/1947
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 37GHz data obtained at Metsahovi Radio Observatory in 2001 December-2005 April for a large sample of BL Lacertae objects. Metsahovi radio telescope is a radome enclosed antenna with a diameter of 13.7 metres. The 37 GHz receiver is a dual horn, Dicke-switched receiver with a HEMT preamplifier, and is operated at room temperature. The observations are ON-ON observations, alternating the source and the sky in each feed horn. A typical integration time to obtain one flux density data point is 1200-1600s, and the detection limit under optimal weather conditions is about 0.2Jy.
- ID:
- ivo://CDS.VizieR/J/ApJ/731/L41
- Title:
- 1.4GHz observations of bright early-type galaxies
- Short Name:
- J/ApJ/731/L41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have measured the radio continuum emission of 396 early-type galaxies brighter than K=9, using 1.4GHz imagery from the NRAO Very Large Array Sky Survey, Green Bank 300ft Telescope, and 64m Parkes Radio Telescope. For M_K_<-24 early-type galaxies, the distribution of radio powers at fixed absolute magnitude spans four orders of magnitude and the median radio power is proportional to K-band luminosity to the power 2.78+/-0.16. The measured flux densities of M_K_<-25.5 early-type galaxies are greater than zero in all cases. It is thus highly likely that the most massive galaxies always host an active galactic nucleus or have recently undergone star formation.
- ID:
- ivo://CDS.VizieR/J/ApJ/378/65
- Title:
- 8.4GHz observations of compact starbursts
- Short Name:
- J/ApJ/378/65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 40 ultraluminous (log(LFIR/L_{sun}_>=11.25) galaxies in the IRAS Bright Galaxy Sample of sources stronger than S=5.24Jy at {lambda}=60{mu}m were mapped with approximately 0.25-arcsec resolution at 8.44GHz. Twenty-five contain diffuse radio sources obeying the FIR-radio correlation; these are almost certainly starburst galaxies. Fourteen other galaxies have nearly blackbody FIR spectra with color temperatures between 60 and 80K so their (unmeasured) FIR angular sizes must exceed approximately 0.25-arcsec, yet they contain compact (but usually resolved) radio sources smaller than this limit. The unique radio and FIR properties of these galaxies can be modeled by ultraluminous nuclear starbursts so dense that they are optically thick to free-free absorption at {nu}~1.49GHz and dust absorption at {lambda}~25{mu}m. Only one galaxy (UGC 08058 = Mrk 231) is a dominated by a variable radio source too compact to be an ultraluminous starburst; it must be powered by a 'monster'.
- ID:
- ivo://CDS.VizieR/J/MNRAS/430/1961
- Title:
- 93.2GHz observations of 9C sources
- Short Name:
- J/MNRAS/430/1961
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from follow-up observations of a sample of 80 radio sources, originally detected as part of the 15.2-GHz Ninth Cambridge (9C) survey. The observations were carried out, close to simultaneously, at two frequencies: 15.7GHz, using the Arcminute Microkelvin Imager (AMI) Large Array, and 93.2GHz, using the Combined Array for Research in Millimeter-wave Astronomy (CARMA). There is currently little direct information on the 90-GHz-band source count for S<~1Jy. However, we have used the measured 15.7-to-93.2-GHz spectral-index distribution and 9C source count to predict the differential source count at 93.2GHz as 26+/-4(S/Jy)^-2.15^Jy^-1^sr^-1^; our projection is estimated to be most accurate for 10<~S<~100mJy. Our estimated differential count is more than twice the 90-GHz prediction made by Waldram et al. (2007, Cat. J/MNRAS/379/1442); we believe that this discrepancy is because the measured 43-GHz flux densities used in making their prediction were too low. Similarly, our prediction is significantly higher than that of Sadler et al. (2008, Cat. J/MNRAS/385/1656) at 95GHz. Since our spectral-index distribution is similar to the 20-to-95-GHz distribution measured by Sadler et al. and used in making their prediction, we believe that the difference is almost entirely attributable to the dissimilarity in the lower frequency counts used in making the estimates.
- ID:
- ivo://CDS.VizieR/J/A+A/658/A39
- Title:
- 31.0-50.3 GHz observations of IRC+10216
- Short Name:
- J/A+A/658/A39
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- The carbon-rich envelope of the asymptotic giant branch star CW Leo, IRC+10216, is one of the richest molecular sources in the sky. Available spectral surveys below 51GHz are more than 25 years old, and new work is needed. Characterizing the rich molecular content of this source, specially for heavy species, requires carrying out very sensitive spectral surveys at low frequencies. In particular, we have achieved an rms in the range 0.2-0.6mK per MHz. Long Q band (31.0-50.3GHz) single-dish integrations were carried out with the Yebes-40m telescope using specifically built receivers. The most recent line catalogs were used to identify the lines. The data contain 652 spectral features, corresponding to 713 transitions from 81 species (we count the isomers, isotopologs, and ortho/para species separately). Only 57 unidentified lines remain with signal-to-noise ratios >=3. Some new species and/or vibrational modes have been discovered for the first time with this survey. This IRC+10216 spectral survey is by far the most sensitive survey carried out to date in the Q band. It therefore provides the most complete view of IRC+10216 from 31.0 to 50.3GHz, giving unique information about its molecular content, especially for heavy species. Rotational diagrams built from the data provide valuable information about the physical conditions and chemical content of this circumstellar envelope.
- ID:
- ivo://CDS.VizieR/J/A+A/603/A100
- Title:
- 37 GHz observations of NLS1 galaxies
- Short Name:
- J/A+A/603/A100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations performed at Metsahovi Radio Observatory at 37GHz are presented for a sample of 78 radio-loud and radio-quiet narrow-line Seyfert 1 (NLS1) galaxies, together with additional lower and higher frequency radio data from RATAN-600, Owens Valley Radio Observatory, and the Planck satellite. Most of the data have been gathered between February 2012 and April 2015 but for some sources even longer light curves exist. The detection rate at 37GHz is around 19%, which is comparable to other populations of active galactic nuclei presumed to be faint at radio frequencies, such as BL Lac objects. Variability and spectral indices are determined for sources with enough detections. Based on the radio data, many NLS1 galaxies show a blazar-like radio spectra exhibiting significant variability. The spectra at a given time are often inverted or convex. The source of the high-frequency radio emission in NLS1 galaxies, detected at 37GHz, is most probably a relativistic jet rather than star formation. Jets in NLS1 galaxies are therefore expected to be a much more common phenomenon than earlier assumed.
- ID:
- ivo://CDS.VizieR/J/ApJ/634/L89
- Title:
- 4.8GHz observations of SGR 1806-20
- Short Name:
- J/ApJ/634/L89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 2004 December 27 giant {gamma}-ray flare detected from the magnetar SGR 1806-20 created an expanding radio nebula that we have monitored with the Australia Telescope Compact Array and the Very Large Array. These data indicate that there was an increase in the observed flux 25 days after the initial flare that lasted for 8 days, which we believe is the result of ambient material swept up and shocked by this radio nebula.
- ID:
- ivo://CDS.VizieR/J/AJ/142/3
- Title:
- 1.4GHz observations of Stripe 82
- Short Name:
- J/AJ/142/3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a high-resolution radio survey of the Sloan Digital Sky Survey (SDSS) Southern Equatorial Stripe, a.k.a. Stripe 82. This 1.4GHz survey was conducted with the Very Large Array primarily in the A-configuration, with supplemental B-configuration data to increase sensitivity to extended structure. The survey has an angular resolution of 1.8" and achieves a median rms noise of 52{mu}Jy/beam over 92deg^2^. This is the deepest 1.4GHz survey to achieve this large of an area, filling a gap in the phase space between small, deep and large, shallow surveys. It also serves as a pilot project for a larger high-resolution survey with the Expanded Very Large Array. We discuss the technical design of the survey and details of the observations, and we outline our method for data reduction. We present a catalog of 17969 isolated radio components, for an overall source density of ~195sources/deg^2^. The astrometric accuracy of the data is excellent, with an internal check utilizing multiply observed sources yielding an rms scatter of 0.19" in both right ascension and declination. A comparison to the SDSS-DR7 Quasar Catalog further confirms that the astrometry is well tied to the optical reference frame, with mean offsets of 0.02+/-0.01" in right ascension, and 0.01+/-0.02" in declination. A check of our photometry reveals a small, negative CLEAN-like bias on the level of 35{mu}Jy. We report on the catalog completeness, finding that 97% of FIRST-detected quasars are recovered in the new Stripe 82 radio catalog, while faint, extended sources are more likely to be resolved out by the resolution bias. We conclude with a discussion of the optical counterparts to the catalog sources, including 76 newly detected radio quasars.