- ID:
- ivo://CDS.VizieR/J/A+A/623/A123
- Title:
- Einasto parameters for SPARC galaxies
- Short Name:
- J/A+A/623/A123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dark matter-baryon scaling relations in galaxies are important in order to constrain galaxy formation models. Here, we provide a modern quantitative assessment of those relations, by modelling the rotation curves of galaxies from the Spitzer Photometry and Accurate Rotation Curves (SPARC) database with the Einasto dark halo model. We focus in particular on the comparison between the original SPARC parameters, with constant mass-to-light ratios for bulges and disks, and the parameters for which galaxies follow the tightest radial acceleration relation. We show that fits are improved in the second case, and that the pure halo scaling relations also become tighter. We report that the density at the radius where the slope is -2 is strongly anticorrelated to this radius, and to the Einasto index. The latter is close to unity for a large number of galaxies, indicative of large cores. In terms of dark matter-baryon scalings, we focus on relations between the core properties and the extent of the baryonic component, which are relevant to the cusp-core transformation process. We report a positive correlation between the core size of halos with small Einasto index and the stellar disk scale-length, as well as between the averaged dark matter density within 2kpc and the baryon-induced rotational velocity at that radius. This finding is related to the consequence of the radial acceleration relation on the diversity of rotation curve shapes, quantified by the rotational velocity at 2kpc. While a tight radial acceleration relation slightly decreases the observed diversity compared to the original SPARC parameters, the diversity of baryon-induced accelerations at 2kpc is sufficient to induce a large diversity, incompatible with current hydrodynamical simulations of galaxy formation, while maintaining a tight radial acceleration relation.
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- ID:
- ivo://nasa.heasarc/hricfa
- Title:
- Einstein Catalog HRI CFA Sources
- Short Name:
- Einstein/HRI
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table consists of a preliminary source list for the Einstein Observatory's High Resolution Imager (HRI). The source list, obtained from EINLINE, the Einstein On-line Service at the Smithsonian Astrophysical Observatory (SAO), contains basic information about the sources detected with the HRI. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/hrideep
- Title:
- Einstein Catalog HRI Deep Survey
- Short Name:
- EinstHRIDeep
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table contains primary HRI source parameters for the 202 HRI sources found in the Einstein Deep Survey. The Einstein Deep Survey (EDS) program consisted 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. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/hriexo
- Title:
- Einstein Catalog HRI ESTEC Sources
- Short Name:
- HRIEXO
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Einstein High Resolution Imager (HRI) consisted of a micro-channel plate. This database table has been generated at the EXOSAT observatory by automatically processing all the HRI images. Both the images and detected sources are available. This catalog has not been cleaned or checked. Users should beware of two possible problems: (1) spurious detections caused by extended sources have not been checked, and (2) there may be a one-pixel offset in some positions. For HRI images, one pixel is one arcsecond. (The images are rebinned from the original 0.5 arcseconds.) This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ipcdeep
- Title:
- Einstein Catalog IPC Deep Survey
- Short Name:
- IPCDEEP
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- IPCDEEP is created from a table containing basic source parameters for each of the 178 IPC sources detected by the Einstein Deep Survey. 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. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/emss
- Title:
- Einstein Catalog IPC EMSS Survey
- Short Name:
- Einstein/EMSS
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table contains information from the Einstein Extended Medium Sensitivity Survey (EMSS) which 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*10E-14 to ~3*10-12 ergs cm-3 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. Additional information is available from the HEASARC. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ipcslew
- Title:
- Einstein Catalog IPC Slew Survey
- Short Name:
- IPCSLEW
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table contains the list of sources detected in the IPC Slew Survey. It was created in March 1992 and contains 819 entries. The original IPC Slew Survey source list was released on CD-ROM and contained 1067 sources. The list was updated in 1991 to remedy a software bug which omitted a thin slice of RA near 24h; the bug fix yielded 8 additional sources, to bring the total to 1075. The list, however, was found to contain a large fraction (10 to 15 percent) of unreliable sources, especially those sources with <= 5 photons. The unreliable sources were rejected in producing the latest version of the source list, so that it now has an estimated false source rate of only 2 percent, and contains 256 fewer sources than the previous version. The previous version of the source list, with 1075 sources, has been retained in a database called OLDIPCSLEW. The HEASARC implemented this database table in March 1992. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ipcostars
- Title:
- Einstein Count Rates for IPC O Stars
- Short Name:
- IPCOstars
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This information, derived from the Einstein X-ray Observatory Catalog of O-type Stars, by Chlebowski, Harnden and Sciortino, provides information regarding the Soft X-ray measurements for all normal, massive, O-type stars serveyed with The Einstein Observatory. More information is available through the HEASARC. This is a service provided by NASA HEASARC .
- 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.
4100. 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.