- ID:
- ivo://CDS.VizieR/J/A+A/332/586
- Title:
- Cataclysmic variables light curves
- Short Name:
- J/A+A/332/586
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Wavelet transforms of a large quantity of light curves of numerous CVs in different photometric states were performed in order to quantify the behaviour of the flickering in a statistically significant sample of systems. The scalegram is used as the appropriate tool to describe the wavelet coefficients of stochastically variable data as a function of the time scale. The (logarithmic) scalegram being largely linear for all light curves shows that flickering is a self-similar process and permits a parametrization in terms of its inclination {alpha} and its value {SIGMA} (flickering strength) at a reference time scale. For a given system, {alpha} and {SIGMA} are stable over many years but can vary over shorter periods and are then loosely correlated. On average flickering on short time scales is somewhat bluer than on longer scales. CVs of different types (and photometric states) occupy distinct regions in the {alpha}-{SIGMA}-plane. This behaviour is particularly clear cut for novalike variables where UX UMa stars overlap only slightly with VY Scl stars, and magnetic CVs populate a small range well separated from the other systems. The intrinsic flickering amplitudes of most dwarf novae vary around the outburst cycle with the square root of the system brightness. In dwarf novae with a strong orbital hump the inclination of the scalegram steepens during the outburst. Due probably to complex functional dependences between observable quantities, the physical origins of the flickering, and dynamical system parameters, no clear correlation (only some trends) between flickering characteristics and dynamical or geometrical properties of the CVs can be seen.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/465/4968
- Title:
- Cataclysmic variables observations
- Short Name:
- J/MNRAS/465/4968
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new time-resolved photometry of 74 cataclysmic variables (CVs), 47 of which are eclipsing. Thirteen of these eclipsing systems are newly discovered. For all 47 eclipsing systems, we show high cadence (1-20s) light curves obtained with the high-speed cameras ULTRACAM and ULTRASPEC. We provide new or refined ephemerides, and supply mid-eclipse times for all observed eclipses. We assess the potential for light-curve modelling of all 47 eclipsing systems to determine their system parameters, finding 20 systems that appear to be suitable for future study. Systems of particular interest include V713 Cep, in which we observed a temporary switching-off of accretion; and ASASSN-14mv and CSS111019:233313-155744, which both have orbital periods well below the CV period minimum. The short orbital periods and light-curve shapes suggest that they may be double degenerate (AM CVn) systems or CVs with evolved donor stars.
- ID:
- ivo://CDS.VizieR/J/A+A/312/93
- Title:
- Cataclysmic variables systemic-velocity
- Short Name:
- J/A+A/312/93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have collected {gamma} velocities of cataclysmic variables from a survey of published orbital radial-velocity studies. We argue that for the non-magnetic cataclysmic variables the {gamma} distribution gives a fair description of the systemic radial velocities; for magnetic cataclysmic variables the effect of motions within the system appears to be substantial. Assuming that the distribution of the spatial velocities of cataclysmic variables in the solar neighbourhood follows the velocity ellipsoid, with dispersions as given by Wielen (1977), we estimate that the dispersion of z-velocities of CVs is in the range 16 to 21km/s. With the galactic potential of Kuijken and Gilmore (1989) we then derive the distribution of distances, z, above the galactic plane. This distribution has an exponential scale height in the range 160-230pc, which is nearly a factor of two larger than that obtained for the z distribution of systems with known distances. This probably reflects the incompleteness of the census of cataclysmic variables at distances even as small as ~100pc. The velocity distribution of cataclysmic variables indicates that they are an old disk population, with a mix of ages up to 10Gyr.
- ID:
- ivo://CDS.VizieR/J/ApJ/696/870
- Title:
- Catalina Real-time Transient Survey (CRTS)
- Short Name:
- J/ApJ/696/870
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the results from the first six months of the Catalina Real-Time Transient Survey (CRTS). In order to search for optical transients (OTs) with timescales of minutes to years, the CRTS analyses data from the Catalina Sky Survey which repeatedly covers 26000 of square degrees on the sky. The CRTS provides a public stream of transients that are bright enough to be followed up using small telescopes. Since the beginning of the survey, all CRTS transients have been made available to astronomers around the world in real time using HTML tables, RSS feeds, and VOEvents. As part of our public outreach program, the detections are now also available in Keyhole Markup Language through Google Sky. The initial discoveries include over 350 unique OTs rising more than 2mag from past measurements. Sixty two of these are classified as supernovae (SNe), based on light curves, prior deep imaging and spectroscopic data. Seventy seven are due to cataclysmic variables (CVs; only 13 previously known), while an additional 100 transients were too infrequently sampled to distinguish between faint CVs and SNe. The remaining OTs include active galactic nucleus, blazars, high-proper-motions stars, highly variable stars (such as UV Ceti stars), and transients of an unknown nature.
- ID:
- ivo://CDS.VizieR/J/ApJS/213/9
- Title:
- Catalina Surveys periodic variable stars
- Short Name:
- J/ApJS/213/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present ~47000 periodic variables found during the analysis of 5.4 million variable star candidates within a 20000deg^2^ region covered by the Catalina Surveys Data Release-1 (CSDR1). Combining these variables with type ab RR Lyrae from our previous work, we produce an online catalog containing periods, amplitudes, and classifications for ~61000 periodic variables. By cross-matching these variables with those from prior surveys, we find that >90% of the ~8000 known periodic variables in the survey region are recovered. For these sources, we find excellent agreement between our catalog and prior values of luminosity, period, and amplitude as well as classification. We investigate the rate of confusion between objects classified as contact binaries and type c RR Lyrae (RRc's) based on periods, colors, amplitudes, metallicities, radial velocities, and surface gravities. We find that no more than a few percent of the variables in these classes are misidentified. By deriving distances for this clean sample of ~5500 RRc's, we trace the path of the Sagittarius tidal streams within the Galactic halo. Selecting 146 outer-halo RRc's with SDSS radial velocities, we confirm the presence of a coherent halo structure that is inconsistent with current N-body simulations of the Sagittarius tidal stream. We also find numerous long-period variables that are very likely associated within the Sagittarius tidal stream system. Based on the examination of 31000 contact binary light curves we find evidence for two subgroups exhibiting irregular light curves. One subgroup presents significant variations in mean brightness that are likely due to chromospheric activity. The other subgroup shows stable modulations over more than a thousand days and thereby provides evidence that the O'Connell effect is not due to stellar spots.
- ID:
- ivo://CDS.VizieR/V/94
- Title:
- Catalog and Atlas of Cataclysmic Variables
- Short Name:
- V/94
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains data for 1020 cataclysmic variables (CVs). It includes coordinates measured in the reference frame of the Hubble Space Telescope Guide Star Survey for non-novae and from the literature for novae. Also given are the variability type, the magnitude range, references to finding charts and spectroscopy, the galactic latitude and longitude, and the year of outburst for novae. The second edition includes plate identification information for the coordinate measurements, a reference to the classification, proper motion information where appropriate and a table showing the CVs observed by space-based observatories. This version of the catalog includes 195 new objects (172 CVs and 23 non-CVs), revised identifications for 57 objects, and revised classifications and spectral references where available.
- ID:
- ivo://nasa.heasarc/caixa
- Title:
- Catalog of AGN in the XMM-Newton Archive
- Short Name:
- CAIXA
- Date:
- 25 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table comprises CAIXA, the "Catalog of AGN In the XMM-Newton Archive". It consists of all the radio-quiet, X-ray unobscured (N<sub>H</sub> < 2 x 10<sup>22</sup> cm<sup>-2</sup>) active galactic nuclei (AGN) observed by XMM-Newton in targeted observations, whose data were public as of March 2007. With its 156 sources, this is the largest catalog of high signal-to-noise X-ray spectra of AGN. All the EPIC pn spectra of the sources in CAIXA were extracted homogeneously, and a baseline model was applied in order to derive their basic X-ray properties. These data are complemented by multiwavelength data found in the literature: black hole masses, full width half maximum (FWHM) of H(beta), radio and optical fluxes. In their paper, the authors describe their homogeneous spectral analysis of the X-ray data in CAIXA and present all the results for the parameters adopted in their best-fit models. This table was created by the HEASARC in March 2009 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/495/421">CDS catalog J/A+A/495/421</a> files table1.dat, table2.dat and table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/J/A+A/495/421
- Title:
- Catalog of AGN in XMM-Newton archive (CAIXA)
- Short Name:
- J/A+A/495/421
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CAIXA, a Catalogue of AGN In the XMM-Newton Archive. It consists of all the radio-quiet X-ray unobscured (N_H_<2x10^22^cm^-2^) active galactic nuclei (AGN) observed by XMM-Newton in targeted observations, whose data are public as of March 2007. With its 156 sources, this is the largest catalogue of high signal-to-noise X-ray spectra of AGN. All the EPIC pn spectra of the sources in CAIXA were extracted homogeneously, and a baseline model was applied in order to derive their basic X-ray properties. These data are complemented by multiwavelength data found in the literature: black hole masses, full width half maximum (FWHM) of H{beta}, radio and optical fluxes.
- ID:
- ivo://CDS.VizieR/J/ApJ/640/603
- Title:
- Catalog of AGNs in the GOODS fields
- Short Name:
- J/ApJ/640/603
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present mid-infrared observations of active galactic nuclei (AGNs) in the GOODS fields, performed with the Spitzer Space Telescope. These are the deepest infrared and X-ray fields to date and cover a total area of 0.1{deg}^2^. AGNs are selected on the basis of their hard (28keV) X-ray emission.
- ID:
- ivo://CDS.VizieR/J/MNRAS/411/373
- Title:
- Catalog of AKARI Deep Field South
- Short Name:
- J/MNRAS/411/373
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AKARI Deep Field-South (ADF-S) is a ~12deg^2^ region near the South Ecliptic Pole that has been observed with deep scans in the far-infrared by the AKARI satellite. As such it is becoming one of the key extragalactic survey fields. We here present complementary observations of the ADF-S conducted by the Spitzer Space Telescope at wavelengths of 24 and 70um. We extract source catalogues at each of these wavelengths reaching depths of ~0.2mJy at 24um and ~20mJy at 70um. We also apply a K-to-24um colour criterion to select objects with galaxy-like colours in the 24-um survey. Completeness corrections as a function of flux density are derived for both catalogues by injecting artificial sources of known flux density into the maps, and we find that our surveys are 50 per cent complete at 0.26 and 24mJy at 24 and 70um, respectively.
