- 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.
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- 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/393/1053
- Title:
- 18-cm OH lines in comets
- Short Name:
- J/A+A/393/1053
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Since the apparition of comet Kohoutek 1973 XII, the 18-cm lines of the OH radical have been systematically observed in a number of comets with the Nancay radio telescope. Between 1973 and 1999, 52 comets have been successfully detected. This allowed an evaluation of the cometary water production rates and their evolution with time, as well as a study of several physical processes such as the excitation mechanisms of the OH radio lines, the expansion of cometary atmospheres, their anisotropy in relation to non-gravitational forces, and the Zeeman effect in relation to the cometary magnetic field. Part of these observations and their analysis have already been published. The bulk of the results are now organized in a data base. The present paper is a general presentation of the Nancay cometary data base and a more specific description of the observations of 53 cometary apparitions between 1982 and 1999. Comets observed before 1982 are only partly incorporated in the data base. Observations of comets since 2000 have benefited from a major upgrade of the telescope; they will be presented in forthcoming publications.
285. 5cm OH masers survey
- ID:
- ivo://CDS.VizieR/J/A+A/325/255
- Title:
- 5cm OH masers survey
- Short Name:
- J/A+A/325/255
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have undertaken a comprehensive search for 5 cm OH masers in regions visible from Effelsberg with the 100-m telescope (i.e., those with declinations above -29^o^). Our sample is based on bright sources taken from the IRAS Point Source Catalog and/or from previous 18cm OH and H_ 2_O surveys. Among the 165 sources observed, 16 are new (15 exhibit emission and one source shows both absorption and emission). Two new absorption line sources have been tentatively detected. The general properties of the 5cm OH sources are presented and discussed. The 6035MHz line is more often detected than the 6031MHz line. Nevertheless, the latter line is frequently present, a fact that is not explained by present OH excitation models. Simple calculations tend to show that there are enough FIR photons to pump the 6035 and 6031MHz masers, and we found that the statistics of the ratio S_ radio_/S_ IR_ at 18, 5 and 6cm suggest that the maser pumping efficiency decreases with increasing OH excitation. Variability on short (months) or long (years) time-scales is a common feature in many 5 cm OH sources. We also present observations of the 6 GHz satellite lines and report, besides W3(OH), on two certain and perhaps two newly detected weak sources. Some implications on the excitation of OH are briefly discussed.
- ID:
- ivo://CDS.VizieR/J/A+AS/83/539
- Title:
- 21cm radio continuum survey. I.
- Short Name:
- J/A+AS/83/539
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 21 cm Galactic Plane survey was carried out with the Effelsberg 100-m radio telescope (HPBW = 9.4'). It contains sources from l=357{deg} to l=95.5{deg} and from -4{deg}<b<4{deg}. The data were absolutely calibrated by using the Stockert Northern Sky survey at the same wavelength. Included are 884 compact objects with peak flux densities greater than 98 mJy (or 200 mK Tb) and apparent sizes less than 16'. This survey is especially useful for studying extended emission complexes in the Galactic plane and complements the Effelsberg 11 cm survey of the Galactic plane (Reich et al., Cat. <J/A+AS/85/805>)
- ID:
- ivo://CDS.VizieR/J/A+AS/126/413
- Title:
- 21cm radio continuum survey. II.
- Short Name:
- J/A+AS/126/413
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analysed the 21cm Galactic Plane survey carried out with the Effelsberg 100-m telescope for small diameter sources. We present a list of 1830 radio sources with a maximum apparent size of 16' and peak flux densities >160mK or >79mJy/beam area, and a list of 884 radio sources with a maximum apparent size of 16' and peak flux densities >200mK or >98mJy/beam area.
- ID:
- ivo://CDS.VizieR/J/A+AS/85/805
- Title:
- 11cm radio continuum survey. IV.
- Short Name:
- J/A+AS/85/805
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analysed the 11cm Galactic Plane survey carried out with the Effelsberg 100-m telescope for small diameter sources. We present a list of 6483 radio sources with a maximum apparent size of 12' and peak flux densities >40mJy/beam area. Point-like sources are almost evenly distributed over the surveyed area, except that we miss some sources in the highly confused inner part of the Galaxy and the Cygnus X complex. At Galactic longitudes l>100deg the list of compact sources is almost complete above an integrated flux density limit of 70mJy. Most of them are extragalactic. Extended sources show a concentration towards the Galactic Plane. At longitudes l<100deg the scale height is about 0.6deg. An excess of about 900 extended sources is most likely of Galactic structure.
- ID:
- ivo://CDS.VizieR/J/MNRAS/324/1131
- Title:
- 22-cm radio survey of A3528
- Short Name:
- J/MNRAS/324/1131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report and discuss the results of a 22-cm radio survey carried out with the Australia Telescope Compact Array (ATCA) covering the A3528 complex, a chain formed by the merging ACO clusters A3528-A3530-A3532, located in the central region of the Shapley Concentration. Simultaneous 13-cm observations are also presented. Our final catalogue includes a total of 106 radio sources above the flux density limit of 0.8mJy. By cross-correlation with optical and spectroscopic catalogues we found 32 optical counterparts, nine of them belonging to the A3528 complex.
- ID:
- ivo://CDS.VizieR/J/A+AS/58/197
- Title:
- 11cm survey, 357.4<=l<=76, -1.5<=b<=1.5
- Short Name:
- J/A+AS/58/197
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 11 cm radio continuum radiation of the Galactic Plane is shown in the form of an atlas of contour maps covering the range l=357.4 to 76{deg}, |b|=1.5{deg} or less. The angular resolution is about 4.3arcmin and the sensitivity is 50mK T_B_ (or 20mJy/beam area). Additionally a catalog of 1212 small diameter radio sources has been compiled.