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721. Cataclysmic variables in the 2MASS 2IDR
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.
722. Cataclysmic variables in the ZTF 1st-yr (2018-2019)
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.
723. Cataclysmic variables in ZTF 2nd year
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.
724. Cataclysmic variables observations
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.
725. Catalina Surveys periodic variable 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.
726. Catalog of AKARI Deep Field South
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.
727. Catalog of barred galaxies
ID:
ivo://CDS.VizieR/J/other/Ap/41.1
Title:
Catalog of barred galaxies
Short Name:
J/other/Ap/41.1
Date:
21 Oct 2021
Publisher:
CDS
Description:
A catalog of barred spiral galaxies of types SB and SAB with B_T_=<13.5 and DE>-10{deg} has been compiled. Some parameters of these galaxies are given.
728. Catalog of dense cores in Aquila from Herschel
ID:
ivo://CDS.VizieR/J/A+A/584/A91
Title:
Catalog of dense cores in Aquila from Herschel
Short Name:
J/A+A/584/A91
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present and discuss the results of the Herschel Gould Belt survey (HGBS) observations in an ~11deg^2^ area of the Aquila molecular cloud complex at d~260pc, imaged with the SPIRE and PACS photometric cameras in parallel mode from 70-micron to 500-micron. Using the multi-scale, multi-wavelength source extraction algorithm getsources, we identify a complete sample of starless dense cores and embedded (Class 0-I) protostars in this region, and analyze their global properties and spatial distributions. We find a total of 651 starless cores, ~60% +/-10% of which are gravitationally bound prestellar cores, and they will likely form stars in the future. We also detect 58 protostellar cores. The core mass function (CMF) derived for the large population of prestellar cores is very similar in shape to the stellar initial mass function (IMF), confirming earlier findings on a much stronger statistical basis and supporting the view that there is a close physical link between the stellar IMF and the prestellar CMF. The global shift in mass scale observed between the CMF and the IMF is consistent with a typical star formation efficiency of ~40% at the level of an individual core. By comparing the numbers of starless cores in various density bins to the number of young stellar objects (YSOs), we estimate that the lifetime of prestellar cores is ~1Myr, which is typically ~4 times longer than the core free-fall time, and that it decreases with average core density. We find a strong correlation between the spatial distribution of prestellar cores and the densest filaments observed in the Aquila complex. About 90% of the Herschel-identified prestellar cores are located above a background column density corresponding to A_V_~7, and ~75% of them lie within filamentary structures with supercritical masses per unit length >~16M_{sun}_/pc. These findings support a picture wherein the cores making up the peak of the CMF (and probably responsible for the base of the IMF) result primarily from the gravitational fragmentation of marginally supercritical filaments. Given that filaments appear to dominate the mass budget of dense gas at A_V_>7, our findings also suggest that the physics of prestellar core formation within filaments is responsible for a characteristic "efficiency" SFR/M_dense_~5+/-2x10^-8^yr^-1^ for the star formation process in dense gas.
729. Catalog of dense cores in Oph molecular cloud
ID:
ivo://CDS.VizieR/J/A+A/638/A74
Title:
Catalog of dense cores in Oph molecular cloud
Short Name:
J/A+A/638/A74
Date:
02 Mar 2022 11:56:27
Publisher:
CDS
Description:
Herschel observations of nearby clouds in the Gould Belt support a paradigm for low-mass star formation, starting with the generation of molecular filaments, followed by filament fragmentation, and the concentration of mass into self-gravitating prestellar cores. With the unique far-infrared and submillimeter continuum imaging capabilities of the Herschel Space observatory, the closeby (d=139pc) Ophiuchus cloud was mapped at five wavelengths from 70 microns to 500 microns with the aim of providing a complete census of dense cores in this region, including unbound starless cores, bound prestellar cores, and protostellar cores. Taking advantage of the high dynamic range and multi-wavelength nature of the Herschel data, we used the multi-scale decomposition algorithms getsources and getfilaments to identify a complete sample of dense cores and filaments in the cloud and study their properties. The densest clouds of the Ophiuchus complex, L1688 and L1689, which thus far are only indirectly described as filamentary regions owing to the spatial distribution of their young stellar objects (YSOs), are confirmed to be dominated by filamentary structures. The tight correlation observed between prestellar cores and filamentary structures in L1688 and L1689 supports the view that solar-type star formation occurs primarily in dense filaments. While the sub clouds of the complex show disparities, L1689 being less efficient than L1688 at forming stars when considering their total mass budgets, both sub clouds share almost the same prestellar core formation efficiency in dense molecular gas. We also find evidence in the Herschel data for a remarkable concentric geometrical configuration in L1688 which is dominated by up to three arc-like compression fronts and presumably created by shockwave events emanating from the Sco OB2 association, including the neighboring massive (O9V) star sigma Sco.
730. Catalog of dense cores in Orion B from Herschel
ID:
ivo://CDS.VizieR/J/A+A/635/A34
Title:
Catalog of dense cores in Orion B from Herschel
Short Name:
J/A+A/635/A34
Date:
14 Jan 2022 08:07:23
Publisher:
CDS
Description:
We present a detailed study of the Orion B molecular cloud complex (d~400pc), which was imaged with the PACS and SPIRE photometric cameras at wavelengths from 70-micron to 500-micron as part of the Herschel Gould Belt survey (HGBS). We release new high-resolution maps of column density and dust temperature for the whole complex, derived in the same consistent manner as for other HGBS regions. In the filamentary subregions NGC2023 and 2024, NGC2068 and 2071, and L1622, a total of 1768 starless dense cores were identified based on Herschel data, 490-804 (~28-45%) of which are self-gravitating prestellar cores that will likely form stars in the future. A total of 76 protostellar dense cores were also found. The typical lifetime of the prestellar cores was estimated to be t_pre_^OrionB^=1.7(-0.6/+0.8)Myr. The prestellar core mass function (CMF) derived for the whole sample of prestellar cores peaks at ~0.5Msun (in dN/dlogM format) and is consistent with a power-law with logarithmic slope -1.27+/-0.24 at the high-mass end, compared to the Salpeter slope of -1.35. In the Orion B region, we confirm the existence of a transition in prestellar core formation efficiency (CFE) around a fiducial value A_V_^bg^~7mag in background visual extinction, which is similar to the trend observed with Herschel in other regions, such as the Aquila cloud. This is not a sharp threshold, however, but a smooth transition between a regime with very low prestellar CFE at A_V_^bg^<5 and a regime with higher, roughly constant CFE at A_V_^bg^>~10. The total mass in the form of prestellar cores represents only a modest fraction (~20%) of the dense molecular cloud gas above A_V_^bg^>~7mag. About 60-80% of the prestellar cores are closely associated with filaments, and this fraction increases up to >90% when a more complete sample of filamentary structures is considered. Interestingly, the median separation observed between nearest core neighbors corresponds to the typical inner filament width of ~0.1pc, which is commonly observed in nearby molecular clouds, including Orion B. Analysis of the CMF observed as a function of background cloud column density shows that the most massive prestellar cores are spatially segregated in the highest column density areas, and suggests that both higher- and lower-mass prestellar cores may form in denser filaments.