- ID:
- ivo://CDS.VizieR/J/ApJS/219/27
- Title:
- Surveys of asteroid rotation periods using iPTF
- Short Name:
- J/ApJS/219/27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Two dedicated asteroid rotation-period surveys have been carried out in the R band with ~20 minute cadence using the intermediate Palomar Transient Factory (iPTF) during 2014 January 6-9 and February 20-23. The total survey area covered 174deg^2^ in the ecliptic plane. Reliable rotation periods for 1438 asteroids are obtained from a larger data set of 6551 mostly main-belt asteroids, each with >=10 detections. Analysis of 1751, PTF-based, reliable rotation periods clearly shows the spin barrier at ~2hr for rubble-pile asteroids. We found a new large super-fast rotator, 2005 UW163, and another five candidates as well. For asteroids of 3<D<15km, our spin-rate distribution shows a number decrease along with frequency after 5 rev/day, which is consistent with the results of the Asteroid Light Curve Database. The discrepancy between our work and that of Pravec et al. (update 2014 April 20) comes mainly from asteroids with {Delta}_m_<0.2mag, which could be the result of different survey strategies. For asteroids with D<3km, we see a significant number drop at f=6rev/day. The relatively short YORP effect timescale for small asteroids could have spun up those elongated objects to reach their spin-rate limit resulting in breakup to create such a number deficiency. We also see that the C-type asteroids show a smaller spin-rate limit than the S-type, which agrees with the general impression that C-type asteroids have a lower bulk density than S-type asteroids.
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6542. SV Cam BVR light curves
- ID:
- ivo://CDS.VizieR/J/A+A/376/158
- Title:
- SV Cam BVR light curves
- Short Name:
- J/A+A/376/158
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New BVR light curves and times of minimum light for the short period RS CVn system SV Cam were analysed to derive the physical parameters of the system and the parameters of the third body orbit. The light curves obtained at the TUEBITAK National Observatory during two nights in 2000 show considerable asymmetry and night-to-night variations. The analysis of the light curves is made using Djurasevic's inverse problem method. The Roche model with spotted areas on the hotter primary component yields a good fit to observations. The extensive series of published photoelectric minima times indicate that the eclipsing pair orbits around the common mass center of the triple system with a period of 41.32yr.
- ID:
- ivo://CDS.VizieR/J/A+A/406/193
- Title:
- SV Cam BVR light curves in Feb. 2001 - March 2002
- Short Name:
- J/A+A/406/193
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the analysis of new BVR light curves for the active star SV Cam. The Roche model with spotted areas on the hotter primary component fits satisfactorily all filter observations yielding two spots in intermediate latitudes and covering about 1.5% each of the stellar surface. Both are ~1000K cooler than surrounding photosphere. The comparison with an earlier season (January/February 2000) suggests that the spots probably evolved in area longitude and latitude but basic and preferred orientation from previous season is confirmed. The comparison stars were SAO 1045 (standard) and SAO 1030 (check).
- ID:
- ivo://CDS.VizieR/J/AN/325/424
- Title:
- SV Cam VB differential photometry
- Short Name:
- J/AN/325/424
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present analysis and spot solutions based on yet unpublished B and V photoelectric observations on the active binary system SV Cam, carried out at Piszkesteto Mountain Station of Konkoly Observatory Budapest. The present spot solutions are based on the observed light curves in September 1993 and July 1994. Comparison of recent and older spot solutions - taken from the literature - suggests long term differences, but these divergences might be caused by some differences of the applied computational methods.
- ID:
- ivo://CDS.VizieR/J/MNRAS/458/3479
- Title:
- SVM selection of WISE YSO Candidates
- Short Name:
- J/MNRAS/458/3479
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explored the AllWISE catalogue of the Wide-field Infrared Survey Explorer mission and identified Young Stellar Object candidates. Reliable 2MASS and WISE photometric data combined with Planck dust opacity values were used to build our dataset and to find the best classification scheme. A sophisticated statistical method, the Support Vector Machine (SVM) is used to analyse the multi-dimensional data space and to remove source types identified as contaminants (extragalactic sources, main sequence stars, evolved stars and sources related to the interstellar medium). Objects listed in the SIMBAD database are used to identify the already known sources and to train our method. A new all-sky selection of 133,980 Class I/II YSO candidates is presented. The estimated contamination was found to be well below 1% based on comparison with our SIMBAD training set. We also compare our results to that of existing methods and catalogues. The SVM selection process successfully identified >90% of the Class I/II YSOs based on comparison with photometric and spectroscopic YSO catalogues. Our conclusion is that by using the SVM, our classification is able to identify more known YSOs of the training sample than other methods based on colour-colour and magnitude-colour selection. The distribution of the YSO candidates well correlates with that of the Planck Galactic Cold Clumps in the Taurus-Auriga-Perseus-California region.
- ID:
- ivo://CDS.VizieR/J/A+A/607/A11
- Title:
- SWASP catalogue of RR Lyrae stars
- Short Name:
- J/A+A/607/A11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We set out to compile a catalogue of RRab pulsating variables in the SuperWASP archive and identify candidate Blazhko effect objects within this catalogue. We analysed their light curves and power spectra for correlations in their common characteristics to further our understanding of the phenomenon. Pulsation periods were found for each SWASP RRab object using phase dispersion minimisation techniques. Low frequency periodic signals detected in the CLEAN power spectra of RRab stars were matched with modulation sidebands and combined with pairs of sidebands to produce a list of candidate Blazhko periods. A novel technique was used in an attempt to identify Blazhko effect stars by comparing scatter at different parts of the folded light curve. Pulsation amplitudes were calculated based on phase folded light curves. The SuperWASP RRab catalogue consists of 4963 objects of which 3397 are previously unknown. We discovered 983 distinct candidates for Blazhko effect objects, 613 of these being previously unknown in the literature as RR Lyrae stars, and 894 are previously unknown to be Blazhko effect stars. Correlations were investigated between the scatter of points on the light curve, the periods and amplitudes of the objects' pulsations, and those of the Blazhko effect.
- ID:
- ivo://CDS.VizieR/J/AJ/155/201
- Title:
- SweetSpot DR1: 74 SNe Ia in 36 nights on WIYN+WHIRC
- Short Name:
- J/AJ/155/201
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- SweetSpot is a 3 yr National Optical Astronomy Observatory (NOAO) survey program to observe Type Ia supernovae (SNe Ia) in the smooth Hubble flow with the WIYN High-resolution Infrared Camera (WHIRC) on the WIYN 3.5 m telescope. We present data from the first half of this survey, covering the 2011B-2013B NOAO semesters and consisting of 493 calibrated images of 74 SNe Ia observed in the rest-frame near-infrared (NIR) in the range 0.02<z<0.09. Because many observed supernovae require host-galaxy subtraction from templates taken in later semesters, this release contains only the 186 NIR (JHK_s_) data points for the 33 SNe Ia that do not require host-galaxy subtraction. The sample includes four objects with coverage beginning before the epoch of B-band maximum and 27 beginning within 20 days of B-band maximum. We also provide photometric calibration between the WIYN+WHIRC and Two Micron All-Sky Survey (2MASS) systems, along with light curves for 786 2MASS stars observed alongside the SNe Ia. This work is the first in a planned series of three SweetSpot Data Releases. Future releases will include the full set of images from all 3 yr of the survey, including host-galaxy reference images and updated data processing with host-galaxy reference subtraction. SweetSpot will provide a well-calibrated sample that will help improve our ability to standardize distance measurements to SNe Ia, examine the intrinsic optical-NIR colors of SNe Ia at different epochs, explore the nature of dust in other galaxies, and act as a stepping-stone for more distant, potentially space-based surveys.
- ID:
- ivo://CDS.VizieR/J/ApJS/218/8
- Title:
- Swift AGN and Cluster Survey (SACS). I.
- Short Name:
- J/ApJS/218/8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Swift active galactic nucleus (AGN) and Cluster Survey (SACS) uses 125deg^2^ of Swift X-ray Telescope serendipitous fields with variable depths surrounding {gamma}-ray bursts to provide a medium depth (4x10^-15^erg/cm2/s) and area survey filling the gap between deep, narrow Chandra/XMM-Newton surveys and wide, shallow ROSAT surveys. Here, we present a catalog of 22563 point sources and 442 extended sources and examine the number counts of the AGN and galaxy cluster populations. SACS provides excellent constraints on the AGN number counts at the bright end with negligible uncertainties due to cosmic variance, and these constraints are consistent with previous measurements. We use Wide-field Infrared Survey Explorer (WISE) mid-infrared (MIR) colors to classify the sources. For AGNs we can roughly separate the point sources into MIR-red and MIR-blue AGNs, finding roughly equal numbers of each type in the soft X-ray band (0.5-2keV), but fewer MIR-blue sources in the hard X-ray band (2-8keV). The cluster number counts, with 5% uncertainties from cosmic variance, are also consistent with previous surveys but span a much larger continuous flux range. Deep optical or IR follow-up observations of this cluster sample will significantly increase the number of higher-redshift (z>0.5) X-ray-selected clusters.
- ID:
- ivo://CDS.VizieR/J/ApJS/222/13
- Title:
- Swift AGN and Cluster Survey (SWCL). II. SDSS
- Short Name:
- J/ApJS/222/13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study 203 (of 442) Swift AGN and Cluster Survey extended X-ray sources located in the SDSS DR8 footprint to search for galaxy over-densities in three-dimensional space using SDSS galaxy photometric redshifts and positions near the Swift cluster candidates. We find 104 Swift clusters with a >3{sigma} galaxy over-density. The remaining targets are potentially located at higher redshifts and require deeper optical follow-up observations for confirmation as galaxy clusters. We present a series of cluster properties including the redshift, brightest cluster galaxy (BCG) magnitude, BCG-to-X-ray center offset, optical richness, and X-ray luminosity. We also detect red sequences in ~85% of the 104 confirmed clusters. The X-ray luminosity and optical richness for the SDSS confirmed Swift clusters are correlated and follow previously established relations. The distribution of the separations between the X-ray centroids and the most likely BCG is also consistent with expectation. We compare the observed redshift distribution of the sample with a theoretical model, and find that our sample is complete for z<~0.3 and is still 80% complete up to z~0.4, consistent with the SDSS survey depth. These analysis results suggest that our Swift cluster selection algorithm has yielded a statistically well-defined cluster sample for further study of cluster evolution and cosmology. We also match our SDSS confirmed Swift clusters to existing cluster catalogs, and find 42, 23, and 1 matches in optical, X-ray, and Sunyaev-Zel'dovich catalogs, respectively, and so the majority of these clusters are new detections.
- ID:
- ivo://CDS.VizieR/J/ApJ/864/84
- Title:
- Swift follow-up obs. of the TXS 0506+056 blazar
- Short Name:
- J/ApJ/864/84
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Detection of the IceCube-170922A neutrino coincident with the flaring blazar TXS 0506+056, the first and only ~3{sigma} high-energy neutrino source association to date, offers a potential breakthrough in our understanding of high-energy cosmic particles and blazar physics. We present a comprehensive analysis of TXS 0506+056 during its flaring state, using newly collected Swift, NuSTAR, and X-shooter data with Fermi observations and numerical models to constrain the blazar's particle acceleration processes and multimessenger (electromagnetic (EM) and high-energy neutrino) emissions. Accounting properly for EM cascades in the emission region, we find a physically consistent picture only within a hybrid leptonic scenario, with {gamma}-rays produced by external inverse-Compton processes and high-energy neutrinos via a radiatively subdominant hadronic component. We derive robust constraints on the blazar's neutrino and cosmic-ray emissions and demonstrate that, because of cascade effects, the 0.1-100keV emissions of TXS 0506+056 serve as a better probe of its hadronic acceleration and high-energy neutrino production processes than its GeV-TeV emissions. If the IceCube neutrino association holds, physical conditions in the TXS 0506+056 jet must be close to optimal for high-energy neutrino production, and are not favorable for ultrahigh-energy cosmic-ray acceleration. Alternatively, the challenges we identify in generating a significant rate of IceCube neutrino detections from TXS 0506+056 may disfavor single-zone models, in which {gamma}-rays and high-energy neutrinos are produced in a single emission region. In concert with continued operations of the high-energy neutrino observatories, we advocate regular X-ray monitoring of TXS 0506+056 and other blazars in order to test single-zone blazar emission models, clarify the nature and extent of their hadronic acceleration processes, and carry out the most sensitive possible search for additional multimessenger sources.
