- ID:
- ivo://CDS.VizieR/J/AJ/139/519
- Title:
- Carnegie supernova project. SNe Ia
- Short Name:
- J/AJ/139/519
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Carnegie Supernova Project (CSP) is a five-year survey being carried out at the Las Campanas Observatory to obtain high-quality light curves of ~100 low-redshift Type Ia supernovae (SNe Ia) in a well-defined photometric system. Here we present the first release of photometric data that contains the optical light curves of 35 SNe Ia, and near-infrared light curves for a subset of 25 events. The data comprise 5559 optical (ugriBV) and 1043 near-infrared (Y JHKs) data points in the natural system of the Swope telescope. Twenty-eight SNe have pre-maximum data, and for 15 of these, the observations begin at least 5 days before B maximum. This is one of the most accurate data sets of low-redshift SNe Ia published to date. When completed, the CSP data set will constitute a fundamental reference for precise determinations of cosmological parameters, and serve as a rich resource for comparison with models of SNe Ia.
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- ID:
- ivo://CDS.VizieR/J/AJ/109/2376
- Title:
- Case blue/emission-line galaxies
- Short Name:
- J/AJ/109/2376
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CCD imaging and spectroscopic data for 176 blue and/or emission-line galaxies from Lists I and II of the Case Northern Sky Survey. Our sample consists of all Case galaxies which lie in the region which overlaps the original Slice of the Universe survey. We use the observational data to investigate the physical properties of the galaxies selected by the surveys to compare with various parameters published in the survey lists, and to investigate the selection characteristics and completeness limit of the survey. The majority of the Case galaxies are energized by regions of active star formation; only 5% of the sample are Seyfert galaxies. The dual selection techniques used (both UV-excess and emission lines) allow the survey to detect star-forming galaxies with a wide range of properties and evolutionary states. In particular, the Case survey selects galaxies with lower levels of activity than most previous surveys. The survey also includes a larger fraction of intermediate and low-luminosity galaxies than would be present in a purely magnitude-limited sample. Although galaxies as faint as m_B_=19 are present in the sample, the completeness limit of the UV-excess selected portion of the survey is closer to m_B_=16. The luminosity function of the Case galaxies is derived and compared with that of the "normal" field galaxies in the same volume of space. The shape of the Case luminosity function is similar to that for the field sample. A surprising result is that 31% of the field galaxy population can be accounted for by galaxies of the type selected in the Case survey.
- ID:
- ivo://CDS.VizieR/J/other/RAA/18.68
- Title:
- Cataclysmic variables from LAMOST DR3
- Short Name:
- J/other/RAA/18.6
- Date:
- 15 Dec 2021 07:16:35
- Publisher:
- CDS
- Description:
- Big data in the form of stellar spectra from the spectroscopic survey associated with the Large Sky Area Multi-object Fiber Spectroscopic Telescope (LAMOST) are important for studying properties of cataclysmic variables (CVs). By cross matching the catalogs of CVs compiled with LAMOST DR3, acquired from October 2011 to July 2015, we obtained the first spectroscopic catalog for CVs observed by LAMOST with high signal to noise ratio, above 8. By integrating line profiles, their equivalent widths (EWs) of the H{alpha}, H{beta}, H{gamma} and H{delta}, as well as HeI 5876 and 6678{AA} lines, were calculated. There were 74 stellar spectra from 48 known CVs and three spectra from three new CV candidates. At the same time, we also collected their previously published EWs. Thirty-three objects had repeated spectra and 30 stars showed spectral variability in the H{alpha} line. Moreover, we carried out photometric follow-up studies for five CVs (UU Aqr, TT Tri, PX And, BP Lyn and RW Tri). We obtained nine new light curves and revised their linear ephemerides. For RW Tri, there is a possible oscillation with an amplitude of 0.0031(2) days and a period of 47.6+/-0.4 years, which might be caused by a third body (brown dwarf) or magnetic activity cycle.
- ID:
- ivo://CDS.VizieR/J/AJ/134/185
- Title:
- Cataclysmic variables from SDSS-DR5
- Short Name:
- J/AJ/134/185
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 28 cataclysmic variables (CVs) found in 2005 in the Sloan Digital Sky Survey are presented with their coordinates, magnitudes, and spectra. Five of these systems are previously known CVs (HH Cnc, SX LMi, QZ Ser, AP CrB, and HS 1016+3412), and the rest are new discoveries. Additional spectroscopic, photometric, and/or polarimetric observations of 10 systems were carried out, resulting in estimates of the orbital periods for seven of the new binaries. The 23 new CVs include one eclipsing system, one new Polar, and five systems whose spectra clearly reveal atmospheric absorption lines from the underlying white dwarf.
- ID:
- ivo://CDS.VizieR/J/ApJ/565/511
- Title:
- Cataclysmic variables in the 2MASS 2IDR
- Short Name:
- J/ApJ/565/511
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Cataclysmic variables (CVs) have "traditionally" been observed primarily at short wavelengths because accretion-generated luminosity, which peaks in the optical-ultraviolet, dominates the radiated energy of most systems. Hence, relatively little is known about their infrared (IR) properties. Investigating CVs in the IR will contribute to the understanding of key system components that are expected to radiate at these wavelengths, such as the cool outer disk, accretion stream, and secondary star. We have compiled the near-IR J, H, and Ks band photometry of all cataclysmic variables contained in the sky coverage of the Second Incremental Data Release of the 2 Micron All Sky Survey (2MASS). This data comprises 251 cataclysmic variables with reliably identified near-IR counterparts and S/N>10 photometry in one or more of the three near-IR bands. In addition to tables containing the 2MASS data, we present a set of near-IR finding charts for selected systems.
- ID:
- ivo://CDS.VizieR/J/AJ/159/198
- Title:
- Cataclysmic variables in the ZTF 1st-yr (2018-2019)
- Short Name:
- J/AJ/159/198
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using selection criteria based on amplitude, time, and color, we have identified 329 objects as known or candidate cataclysmic variables (CVs) during the first year of testing and operation of the Zwicky Transient Facility. Of these, 90 are previously confirmed CVs, 218 are strong candidates based on the shape and color of their light curves obtained during 3-562days of observation, and the remaining 21 are possible CVs but with too few data points to be listed as good candidates. Almost half of the strong candidates are within 10{deg} of the galactic plane, in contrast to most other large surveys that have avoided crowded fields. The available Gaia parallaxes are consistent with sampling the low mass transfer CVs, as predicted by population models. Our follow-up spectra have confirmed Balmer/helium emission lines in 27 objects, with four showing high-excitation HeII emission, including candidates for an AM CVn, a polar, and an intermediate polar. Our results demonstrate that a complete survey of the Galactic plane is needed to accomplish an accurate determination of the number of CVs existing in the Milky Way.
- ID:
- ivo://CDS.VizieR/J/AJ/162/94
- Title:
- Cataclysmic variables in ZTF 2nd year
- Short Name:
- J/AJ/162/94
- Date:
- 09 Mar 2022 22:00:00
- Publisher:
- CDS
- Description:
- Using a filter in the GROWTH Marshal based on color and the amplitude and timescale of variability, we have identified 372 objects as known or candidate cataclysmic variables (CVs) during the second year of the operation of the Zwicky Transient Facility. From the available difference imaging data, we found that 93 are previously confirmed CVs and 279 are strong candidates. Spectra of four of the candidates confirm them as CVs by the presence of Balmer emission lines, while one of the four has prominent HeII lines indicative of containing a magnetic white dwarf. Gaia EDR3 parallaxes are available for 154 of these systems, resulting in distances from 108-2096pc and absolute magnitudes in the range of 7.5-15.0, with the largest number of candidates between 10.5 and 12.5. The total numbers are 21% higher than from the previous year of the survey with a greater number of distances available but a smaller percentage of systems close to the Galactic plane. Comparison of these findings with a machine-learning method of searching all the light curves reveals large differences in each data set related to the parameters involved in the search process.
- 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.
- 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/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.
