- ID:
- ivo://CDS.VizieR/J/AZh/71/110
- Title:
- Supernova Remnants at Meter Wavelengths
- Short Name:
- J/AZh/71/110
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The total flux densities of more than one hundred galactic supernova remnants (SNR) at 111, 102, and 83MHz, measured at Pushchino using the E-W WBCR-1000 and LSA radio telescopes, to an accuracy of 2Jy or better; the spectral indices, with their errors, obtained from the compiled spectra; and optical depths at 100MHz in the direction of the supernova remnants are reported. The latter values are obtained from a low frequency cutoff caused by interstellar gas absorption, which was detected at meter and decimeter wavelengths in the direction of 38% of the supernova remnants.
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18352. Supernova remnants in M33
- ID:
- ivo://CDS.VizieR/J/ApJS/120/247
- Title:
- Supernova remnants in M33
- Short Name:
- J/ApJS/120/247
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using radio data to identify and optical data to confirm, we have established the largest and most complete sample of extragalactic radio-bright supernova remnants (SNRs) in the nearby spiral galaxy M33. We have identified 53 radio SNRs, doubling the size of the earlier survey by Duric et al. (1993A&AS...99..217D).
- ID:
- ivo://CDS.VizieR/J/MNRAS/472/308
- Title:
- Supernova remnants in M33: X-ray properties
- Short Name:
- J/MNRAS/472/308
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out a study of the X-ray properties of the supernova remnant (SNR) population in M33 with XMM-Newton, comprising deep observations of eight fields in M33 covering all of the area within the D_25_ contours, and with a typical luminosity of 7.1x10^34^erg/s (0.2-2.0keV). Here, we report our work to characterize the X-ray properties of the previously identified SNRs in M33, as well as our search for new X-ray detected SNRs. With our deep observations and large field of view we have detected 105 SNRs at the 3{sigma} level, of which 54 SNRs are newly detected in X-rays, and three are newly discovered SNRs. Combining XMM-Newton data with deep Chandra survey data allows detailed spectral fitting of 15 SNRs, for which we have measured temperatures, ionization time-scales and individual abundances. This large sample of SNRs allows us to construct an X-ray luminosity function, and compare its shape to luminosity functions from host galaxies of differing metallicities and star formation rates to look for environmental effects on SNR properties. We conclude that while metallicity may play a role in SNR population characteristics, differing star formation histories on short time-scales, and small-scale environmental effects appear to cause more significant differences between X-ray luminosity distributions. In addition, we analyse the X-ray detectability of SNRs, and find that in M33 SNRs with higher [SII]/H{alpha} ratios, as well as those with smaller galactocentric distances, are more detectable in X-rays.
- ID:
- ivo://CDS.VizieR/J/other/NewA/5.137
- Title:
- Supersoft X-ray sources catalog
- Short Name:
- J/other/NewA/5.1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog comprises an up-to-date (December 1999) list of luminous (>10^36^erg/s), binary supersoft X-ray sources.
- ID:
- ivo://CDS.VizieR/J/MNRAS/443/1821
- Title:
- Supersoft X-ray sources in M31
- Short Name:
- J/MNRAS/443/1821
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We searched for the optical/UV/IR counterparts of seven supersoft X-ray sources (SSSs) in M31 in the Hubble Space Telescope} (HST}) 'Panchromatic Hubble Andromeda Treasury' (PHAT) archival images and photometric catalogue. Three of the SSSs were transient; the other four are persistent sources. The PHAT offers the opportunity to identify SSSs hosting very massive white dwarfs (WDs) that may explode as Type Ia supernovae in single degenerate binaries, with magnitudes and colour indexes typical of symbiotics, high-mass close binaries, or systems with an optically luminous accretion disc. We find evidence that the transient SSSs were classical or recurrent novae; two probable counterparts that we identified are probably symbiotic binaries undergoing mass transfer at a very high rate. There is a candidate accreting WD binary in the error circle of one of the persistent sources, r3-8. In the spatial error circle of the best-studied SSS in M31, r2-12, no red giants or AGB stars are sufficiently luminous in the optical and UV bands to be symbiotic systems hosting an accreting and hydrogen-burning WD. This SSS has a known modulation of the X-ray flux with a 217.7s period, and we measured an upper limit on its derivative, namely |dP/dt|<~0.82x10^11. This limit can be reconciled with the rotation period of a WD accreting at a high rate in a binary with an orbital period of a few hours. However, there is no luminous counterpart with colour indexes typical of an accretion disc irradiated by a hot central source. Adopting a semi-empirical relationship, the upper limit for the disc optical luminosity implies an upper limit of only 169-min for the orbital period of the WD binary.
- ID:
- ivo://CDS.VizieR/J/A+A/506/519
- Title:
- Supervised classification of CoRoT variables
- Short Name:
- J/A+A/506/519
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work, we describe the pipeline for the fast supervised classification of light curves observed by the CoRoT exoplanet CCDs. We present the classification results obtained for the first four measured fields, which represent a one-year in-orbit operation. The basis of the adopted supervised classification methodology has been described in detail in a previous paper, as is its application to the OGLE database. Here, we present the modifications of the algorithms and of the training set, to optimize the performance when applied to the CoRoT data. Classification results are presented for the observed fields IRa01, SRc01, LRc01, and LRa01 of the CoRoT mission. Statistics on the number of variables and the number of objects per class are given and typical light curves of high-probability candidates are shown. We also report on new stellar variability types discovered in the CoRoT data. The full classification results are publicly available.
- ID:
- ivo://CDS.VizieR/J/A+A/475/1159
- Title:
- Supervised classification of variable stars
- Short Name:
- J/A+A/475/1159
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The fast classification of new variable stars is an important step in making them available for further research. Selection of science targets from large databases is much more efficient if they have been classified first. Defining the classes in terms of physical parameters is also important to get an unbiased statistical view on the variability mechanisms and the borders of instability strips. Our goal is twofold: provide an overview of the stellar variability classes that are presently known, in terms of some relevant stellar parameters; use the class descriptions obtained as the basis for an automated `supervised classification' of large databases. Such automated classification will compare and assign new objects to a set of pre-defined variability training classes. For every variability class, a literature search was performed to find as many well-known member stars as possible, or a considerable subset if too many were present. Next, we searched on-line and private databases for their light curves in the visible band and performed period analysis and harmonic fitting. The derived light curve parameters are used to describe the classes and define the training classifiers. We compared the performance of different classifiers in terms of percentage of correct identification, of confusion among classes and of computation time. We describe how well the classes can be separated using the proposed set of parameters and how future improvements can be made, based on new large databases such as the light curves to be assembled by the CoRoT and Kepler space missions. The derived classifiers' performances are so good in terms of success rate and computational speed that we will evaluate them in practice from the application of our methodology to a large subset of variable stars in the OGLE database and from comparison of the results with published OGLE variable star classifications based on human intervention. These results will be published in a subsequent paper.
- ID:
- ivo://CDS.VizieR/J/MNRAS/372/1117
- Title:
- SuperWASP exoplanetary transit survey
- Short Name:
- J/MNRAS/372/1117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometric transit surveys promise to complement the currently known sample of extra-solar planets (ESPs) by providing additional information on the planets and especially their radii. Here, we present ESP candidates from one such survey called, the Wide Angle Search for Planets (WASP) obtained with the SuperWASP wide-field imaging system. Observations were taken with SuperWASP North located in La Palma during the 2004 April to October observing season. The data cover fields between 23 and 03h in RA at declinations above +12{deg}. This amounts to over >>400000 stars with V magnitudes 8-13.5. For the stars brighter than 12.5, we achieve better than 1% photometric precision. Here, we present 41 sources with low-amplitude variability between >>1 and 10mmag, from which we select 12 with periods between 1.2 and 4.4d as the most promising ESP candidates. We discuss the properties of these ESP candidates, the expected fraction of transits recovered for our sample and implications for the frequency and detection of hot-Jupiters.
- ID:
- ivo://CDS.VizieR/J/MNRAS/384/1097
- Title:
- SuperWASP-North extrasolar planet candidates
- Short Name:
- J/MNRAS/384/1097
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Wide Angle Search for Planets (WASP) survey currently operates two installations, designated SuperWASP-N and SuperWASP-S, located in the Northern and Southern hemispheres, respectively. These installations are designed to provide high time-resolution photometry for the purpose of detecting transiting extrasolar planets, asteroids, and transient events. Here, we present results from a transit-hunting observing campaign using SuperWASP-N covering a right ascension (RA) range of 06h<RA<16h. This paper represents the fifth and final in the series of transit candidates released from the 2004 observing season. In total, 729335 stars from 33 fields were monitored with 130566 having sufficient precision to be scanned for transit signatures. Using a robust transit detection algorithm and selection criteria, six stars were found to have events consistent with the signature of a transiting extrasolar planet based on the photometry, including the known transiting planet XO-1b. These transit candidates are presented here along with discussion of follow-up observations and the expected number of candidates in relation to the overall observing strategy.
- ID:
- ivo://CDS.VizieR/J/MNRAS/381/851
- Title:
- SuperWASP-North extrasolar planet candidates
- Short Name:
- J/MNRAS/381/851
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Wide Angle Search for Planets (WASP) photometrically surveys a large number of nearby stars to uncover candidate extrasolar planet systems by virtue of small-amplitude light curve dips on a <=5d time-scale typical of the 'Hot-Jupiters'. Observations with the SuperWASP-North instrument between 2004 April and September produced a rich photometric data set of some 1.3x10^9^ data points from 6.7 million stars. Our custom-built data acquisition and processing system produces ~0.02mag photometric precision at V=13. We present the transit candidates in the 03h-06h RA range. Out of 141895 light curves with sufficient sampling to provide adequate coverage, 2688 show statistically significant transit-like periodicities. Out of these, 44 pass a visual inspection of the light curve, of which 24 are removed through a set of cuts on the statistical significance of artefacts. All but four of the remaining 20 objects are removed when prior information at higher spatial resolution from existing catalogues is taken into account. Of the four candidates remaining, one is considered a good candidate for follow-up observations with three further second-priority targets. We provide detailed information on these candidates, as well as a selection of the false-positives and astrophysical false-alarms that were eliminated, and discuss briefly the impact of sampling on our results.