- ID:
- ivo://CDS.VizieR/J/A+A/376/333
- Title:
- Einstein A-coefficients for C_3_H_4_
- Short Name:
- J/A+A/376/333
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Following tentative detection of cyclopropene (C_3_H_4_) in Sgr B2 through its transition 3_22_-2_21_, several attempts to confirm the presence of cyclopropene in astronomical objects (including Sgr B2 itself) have been made. We suggest that cyclopropene may be observed in astronomical objects through its transition 2_20_-2_21_ at 3.67218GHz, in absorption, even against the cosmic 2.7K background, in a region having low density and low kinetic temperature.
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- ID:
- ivo://CDS.VizieR/J/A+A/402/1
- Title:
- Einstein A-coefficients for C3H2 and C2H4O
- Short Name:
- J/A+A/402/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Cyclopropenylidene C_3_H_2_ and ethylene oxide C_2_H_4_O molecules are of astronomical importance as their observed lines, distributed throughout the observable microwave region, have a number of pairs having nearly equal frequencies, but different excitation energies and/or belonging to two different species of the molecule. Hence, these molecules may play important role in detecting physical conditions in cosmic objects. Therefore, in order to calculate intensities of the lines, we have investigated transfer of radiation through a cosmic object containing the molecule at a kinetic temperature of 10K. Our results show that some lines of the molecule may be found in absorption against the cosmic 2.7K background.
- ID:
- ivo://CDS.VizieR/J/A+AS/114/175
- Title:
- Einstein A-coefficients in CS transitions
- Short Name:
- J/A+AS/114/175
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Einstein A-coefficients for vib-rotational transitions in CS isotopomers, for vibrational quantum number v up to 20, rotational quantum number J up to 140, and {DELTA}v up to 4, are calculated. The change in J is governed by the selection rules {DELTA}J=+/-1. These coefficients play an important role in astronomy, as CS has been observed in a number of astronomical object.
- ID:
- ivo://CDS.VizieR/J/A+AS/131/137
- Title:
- Einstein A-Coefficients in SiC2 transitions
- Short Name:
- J/A+AS/131/137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Einstein A-coefficients for the electric dipole transitions in Silicon Dicarbide molecule and its isotopomers between rotational levels of the ground vibrational state up to 51cm^-1^ are calculated. These coefficients are used for computing radiative life times of the levels. The A-coefficients are one of the important input parameters for the radiative transfer calculations.
- ID:
- ivo://CDS.VizieR/J/A+AS/117/557
- Title:
- Einstein coefficients for CO transitions
- Short Name:
- J/A+AS/117/557
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Einstein A-coefficients for vib-rotational transitions in CO isotopomers, for vibrational quantum number v up to 20, rotational quantum number J up to 140, and {DELTA}v up to 4, are calculated. The change in J is governed by the selection rules {DELTA}J=+/-1. These coefficients play an important role in astronomy, as CO is the most abundant molecule after H_2_, and has been observed in almost all the astronomical objects.
- ID:
- ivo://CDS.VizieR/J/ApJS/92/53
- Title:
- Einstein database of quasars. I.
- Short Name:
- J/ApJS/92/53
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first volume of the Einstein quasar database. The database includes estimates of the X-ray count rates, fluxes, and luminosities for 514 quasars and Seyfert 1 galaxies observed with the Imaging Proportional Counter (IPC) aboard the Einstein Observatory. All were previously known optically selected or radio-selected objects, and most were targets of the X-ray observations. The X-ray properties of the AGNs have been derived by reanalyzing the IPC data in a systematic manner to provide a uniform database for general use by the astronomical community. We use the database to extend earlier quasar luminosity studies which were made using only a subset of the currently available data. The database can be accessed on Internet via the SAO Einstein on-line system ("Einline") and is available in ASCII format on magnetic tape and DOS diskette.
4927. Einstein EMSS Survey
- ID:
- ivo://CDS.VizieR/IX/15
- Title:
- Einstein EMSS Survey
- Short Name:
- IX/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Einstein Extended Medium Sensitivity Survey (EMSS) consists of 835 serendipitous X-ray sources detected at or above 4 times the rms level in 1435 IPC fields with their centers located away from the galactic plane. Their limiting sensitivities range from ~5*10-14 to to ~ 3*10-12 erg.cm-2.s-1 in the 0.3-3.5keV band. A total area of 778 square degrees of the high galactic latitude sky (|b|>20) has been covered. The analysis has been performed using data from the Rev 1 processing system at the CfA. The resulting EMSS catalog is a flux-limited and homogeneous sample of astronomical objects that can be used for statistical studies. Here we present the table listing all the sources taken from the publication referenced below and the optical identifications. At present over 96% of the 835 X-ray sources have been successfully identified in the following proportions: active galactic nuclei (QSO's, quasars and Seyfert), 51.1%; BL Lacertae objects, 4.3%; clusters of galaxies, 12.2%; normal galaxies, 2.1%; cooling flow galaxies, 0.6%; Galactic stars 25.8%; and unidentified, 3.9%. Most of the individual optical counterparts are previously unknown objects and so constitute large statistical samples independent of previously selection methods. The contents of the table is described below. The sky coverage computed for a specific assumed source spectrum is also given under "Additional Information" below. For further details please see the published articles: Gioia et al. 1990, Stocke et al. 1991.
- ID:
- ivo://CDS.VizieR/IX/22
- Title:
- Einstein extended deep survey
- Short Name:
- IX/22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Einstein Deep Survey program (EDS) consists of very deep X-ray exposures in selected regions of the sky at high galactic latitude. The main purposes of the survey are to investigate the nature of the extragalactic X-ray background through direct source counts at very low flux levels and to study the nature of the very faint X-ray sources which comprise a significant fraction, if not all, of the soft X-ray background. The survey includes 9 IPC observations and 34 HRI observations, which, in general, cover the central 32'x32' regions of the IPC fields. In total, 178 IPC sources and 202 HRI sources were detected above thresholds set to allow ~1 false source per observation. Data from all IPC energy bands and all HRI detect cells are included. The data are largely the result of standard Einstein Rev. 1 HRI and Rev. 1B IPC reprocessing; however, minor corrections to IPC count rates, fluxes, and flux significances have been made to account for different column densities toward various fields and small systematic errors in the IPC analysis of count rates and significances for long exposures. For further details please refer to the paper referenced above. The HRI field parameters have been determined from standard processing and from other information contained in the HRI .SDF file. For information on HRI sources, see the table "hsrc.dat"; for information on individual IPC fields, see the table "ifield.dat".
- ID:
- ivo://CDS.VizieR/IX/18
- Title:
- EINSTEIN extended source survey (EXSS)
- Short Name:
- IX/18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains sources from data collected by the IPC on board the EINSTEIN Observatory. This survey is designed to find extended sources and diffuse emission rather than point sources. In addition, the source detection algorithm is substantially improved over that used by EMSS. Sources were searched using circular apertures up to 6.1arcmin. The catalog contains 1326 extended source candidates at high galactic latitude (|b| > 20{deg}).
- ID:
- ivo://CDS.VizieR/J/ApJ/511/65
- Title:
- Einstein images of galaxy clusters
- Short Name:
- J/ApJ/511/65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the X-ray characteristics of a sample of 368 clusters of galaxies with redshifts less than 0.2 observed with the Einstein Imaging Proportional Counter. For each cluster, we measure the 0.5-4.5keV counting rate and compute the 0.5-4.5keV source luminosity, as well as the bolometric luminosity within fixed metric radii. We detect 85% of Abell clusters with z<0.1, demonstrating that the large majority of these optically selected clusters are not the results of chance superpositions. For 163 clusters, we measure their X-ray surface brightness profiles and determine their core radii. For {~}230 clusters, we then use either our measured core radii and values, or mean values derived for this sample, to measure central gas densities and gas masses. We use estimated or measured cluster gas temperatures, along with the derived gas-density profiles, to estimate total cluster masses, under the assumptions that the gas is isothermal and in hydrostatic equilibrium.