- ID:
- ivo://CDS.VizieR/J/MNRAS/392/1456
- Title:
- VIc photometry of M50 (NGC 2323) low-mass stars
- Short Name:
- J/MNRAS/392/1456
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the results of a time-series photometric survey of M50 (NGC 2323), a ~130Myr open cluster, carried out using the Cerro Tololo Inter-American Observatory (CTIO) 4-m Blanco telescope and Mosaic-II detector as part of the Monitor project. Rotation periods were derived for 812 candidate cluster members over the mass range 0.2<=M/M_{sun}_<=1.1. The rotation period distributions show a clear mass-dependent morphology, statistically indistinguishable from those in NGC 2516 and M35 taken from the literature. Due to the availability of data from three observing runs separated by ~10 and 1 month time-scales, we are able to demonstrate clear evidence for evolution of the photometric amplitudes, and hence spot patterns, over the 10 month gap. We are not able to constrain the time-scales for these effects in detail due to limitations imposed by the large gaps in our sampling, which also prevent the use of the phase information.
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Search Results
16822. VIc photometry of NGC 2516
- ID:
- ivo://CDS.VizieR/J/MNRAS/377/741
- Title:
- VIc photometry of NGC 2516
- Short Name:
- J/MNRAS/377/741
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the results of an i-band time-series photometric survey of NGC2516 using the Cerro Tololo Inter-American Observatory (CTIO) 4-m Blanco telescope and 8k Mosaic-II detector, achieving better than 1 per cent photometric precision per data point over 15<~i<~19. Candidate cluster members were selected from a V versus V-I colour-magnitude diagram over 16<V<26 (covering masses from 0.7M_{sun}_ down to below the brown dwarf limit), finding 1685 candidates, of which we expect ~1000 to be real cluster members, taking into account contamination from the field (which is most severe at the extremes of our mass range). Searching for periodic variations in these gave 362 detections over the mass range 0.15<~M/M_{sun}_<~0.7. The rotation period distributions were found to show a remarkable morphology as a function of mass, with the fastest rotators bounded by P>0.25d, and the slowest rotators for M<~0.5M_{sun}_ bounded by a line of P~M3, with those for M>~0.5M_{sun}_ following a flatter relation closer to P ~ constant. Models of the rotational evolution were investigated, finding that the evolution of the fastest rotators was well reproduced by a conventional solid body model with a mass-dependent saturation velocity, whereas core-envelope decoupling was needed to reproduce the evolution of the slowest rotators. None of our models were able to simultaneously reproduce the behaviour of both populations.
- ID:
- ivo://CDS.VizieR/J/MNRAS/383/1588
- Title:
- VIc photometry of NGC 2547 low-mass stars
- Short Name:
- J/MNRAS/383/1588
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the results of an I-band time-series photometric survey of NGC 2547 using the MPG/ESO 2.2-m telescope with Wide Field Imager, achieving better than 1 per cent photometric precision per data point over 14~<I~<18. Candidate cluster members were selected from a V versus V-I colour-magnitude diagram over 12.5<V<24 (covering masses from 0.9M_{sun}_ down to below the brown dwarf limit), finding 800 candidates, of which we expect ~330 to be real cluster members, taking into account contamination from the field (which is most severe at the extremes of our mass range). Searching for periodic variations in these gave 176 detections over the mass range 0.1~<M/M_{sun}_<0.9.
- ID:
- ivo://CDS.VizieR/J/AcA/57/249
- Title:
- VIc photometry of NGC 6755 stars
- Short Name:
- J/AcA/57/249
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results from a search for variable stars in the field of a young open cluster NGC 6755. Altogether seventy one variable stars have been discovered. Thirty one of them are eclipsing systems. This group contains ten EA, four EB and seventeen EW-type systems. Photometric variability of four late type stars is most probably caused by their chromospherical activity. Another seven detected variable stars have light curves typical for pulsating stars from the main instability strip. Four of them we tentatively classified as gamma Dor, one as delta Sct and two as Population II Cepheid variable stars, respectively. Star designated as V40 can be either another population II Cepheid or an ellipsoidal binary system. The remaining twenty eight variable stars found in the field of this open cluster are most probably highly obscured background red giants (OSARG, irregular). For all detected variable stars we provide their light curves, preliminary classification, discussion on the possible cluster membership, equatorial coordinates, finding charts and periods when possible.
- ID:
- ivo://wfau.roe.ac.uk/videoDR5-dsa
- Title:
- VIDEO DR5 - VISTA Deep Extragalactic Observations survey
- Date:
- 25 May 2021 15:50:06
- Publisher:
- WFAU, Institute for Astronomy, University of Edinburgh
- Description:
- The VIDEO survey is a 30 sq. degree, Z,Y,J,H,K survey that is specifically designed to enable exploration of the main issues in observational cosmology. It allows galaxy and cluster/structure evolution to be traced as a function of both epoch and environment from the present day out to z=4 and AGN/QSO evolution up to and into the epoch of reionization at z > 6. The multi-band nature of the survey ensures many key science drivers can be tackled using the survey alone, without recourse to data from other wavebands.
- ID:
- ivo://wfau.roe.ac.uk/videoDR4-dsa
- Title:
- VIDEO DR4 - VISTA Deep Extragalactic Observations survey
- Short Name:
- VIDEO DR4
- Date:
- 04 Dec 2019 13:40:50
- Publisher:
- WFAU, Institute for Astronomy, University of Edinburgh
- Description:
- The VIDEO survey is a 30 sq. degree, Z,Y,J,H,K survey that is specifically designed to enable exploration of the main issues in observational cosmology. It allows galaxy and cluster/structure evolution to be traced as a function of both epoch and environment from the present day out to z=4 and AGN/QSO evolution up to and into the epoch of reionization at z > 6. The multi-band nature of the survey ensures many key science drivers can be tackled using the survey alone, without recourse to data from other wavebands.
- ID:
- ivo://wfau.roe.ac.uk/videoDR3-dsa
- Title:
- VIDEO DR3 - VISTA Deep Extragalactic Observations survey
- Short Name:
- VIDEO DR3
- Date:
- 04 Dec 2019 13:40:40
- Publisher:
- WFAU, Institute for Astronomy, University of Edinburgh
- Description:
- The VIDEO survey is a 30 sq. degree, Z,Y,J,H,K survey that is specifically designed to enable exploration of the main issues in observational cosmology. It allows galaxy and cluster/structure evolution to be traced as a function of both epoch and environment from the present day out to z=4 and AGN/QSO evolution up to and into the epoch of reionization at z > 6. The multi-band nature of the survey ensures many key science drivers can be tackled using the survey alone, without recourse to data from other wavebands.
- ID:
- ivo://wfau.roe.ac.uk/videoDR2-dsa
- Title:
- VIDEO DR2 - VISTA Deep Extragalactic Observations survey
- Short Name:
- VIDEO DR2
- Date:
- 04 Dec 2019 13:40:29
- Publisher:
- WFAU, Institute for Astronomy, University of Edinburgh
- Description:
- The VIDEO survey is a 30 sq. degree, Z,Y,J,H,K survey that is specifically designed to enable exploration of the main issues in observational cosmology. It allows galaxy and cluster/structure evolution to be traced as a function of both epoch and environment from the present day out to z=4 and AGN/QSO evolution up to and into the epoch of reionization at z > 6. The multi-band nature of the survey ensures many key science drivers can be tackled using the survey alone, without recourse to data from other wavebands.
16829. Vienna survey in Orion. III.
- ID:
- ivo://CDS.VizieR/J/A+A/622/A149
- Title:
- Vienna survey in Orion. III.
- Short Name:
- J/A+A/622/A149
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have extended and refined the existing young stellar object (YSO) catalogs for the Orion A molecular cloud, the closest massive star-forming region to Earth. This updated catalog is driven by the large spatial coverage (18.3deg^2^, ~950pc^2^), seeing limited resolution (~0.7''), and sensitivity (K_s_<19mag) of the ESO-VISTA near-infrared survey of the Orion A cloud (VISION). Combined with archival mid- to far-infrared data, the VISTA data allow for a refined and more robust source selection. We estimate that among previously known protostars and pre-main-sequence stars with disks, source contamination levels (false positives) are at least ~6.4% and ~2.3%, respectively, mostly due to background galaxies and nebulosities. We identify 274 new YSO candidates using VISTA/Spitzer based selections within previously analyzed regions, and VISTA/WISE based selections to add sources in the surroundings, beyond previously analyzed regions. The WISE selection method recovers about 59% of the known YSOs in Orion A's low-mass star-forming part L1641, which shows what can be achieved by the all-sky WISE survey in combination with deep near-infrared data in regions without the influence of massive stars. The new catalog contains 2980 YSOs, which were classified based on the de-reddened mid-infrared spectral index into 188 protostars, 185 flat-spectrum sources, and 2607 pre-main-sequence stars with circumstellar disks. We find a statistically significant difference in the spatial distribution of the three evolutionary classes with respect to regions of high dust column-density, confirming that flat-spectrum sources are at a younger evolutionary phase compared to Class IIs, and are not a sub-sample seen at particular viewing angles.
- ID:
- ivo://CDS.VizieR/J/MNRAS/510/687
- Title:
- Viewing angle in AGN SED models
- Short Name:
- J/MNRAS/510/687
- Date:
- 12 Jan 2022 06:30:54
- Publisher:
- CDS
- Description:
- The validity of the unified active galactic nuclei (AGN) model has been challenged in the last decade, especially when different types of AGNs are considered to only differ in the viewing angle to the torus. We aim to assess the importance of the viewing angle in classifying different types of Seyfert galaxies in spectral energy distribution (SED) modelling. We retrieve photometric data from publicly available astronomical databases: CDS and NED, to model SEDs with X-CIGALE in a sample of 13173 Seyfert galaxies located at redshift range from z=0 to z=3.5, with a median redshift of z=~0.2. We assess whether the estimated viewing angle from the SED models reflects different Seyfert classifications. Two AGN models with either a smooth or clumpy torus structure are adopted in this paper. We find that the viewing angle in Type-1 AGNs is better constrained than in Type-2 AGNs. Limiting the viewing angles representing these two types of AGNs do not affect the physical parameter estimates such as star-formation rate (SFR) or AGN fractional contribution (fAGN). In addition, the viewing angle is not the most discriminating physical parameter to differentiate Seyfert types. We suggest that the observed and intrinsic AGN disc luminosity can: i) be used in z<0.5 studies to distinguish between Type-1 and Type-2 AGNs, and ii) explain the probable evolutionary path between these AGN types. Finally, we propose the use of X-CIGALE for AGN galaxy classification tasks. All data from the 13173 SED fits are available at Zenodo.
![To the extent possible under law, the publisher has waived all copyright and related or neighboring rights to the catalogue of astrometric microlensing events. For details, see the `Creative Commons CC0 1.0 Public Domain dedication <http://creativecommons.org/publicdomain/zero/1.0/>`_. Of course, you should still give proper credit when using this data as required by good scientific practice. .. image:: /static/img/cc0.png :alt: [CC0]](/registry-search/?f%5BcapabilityType_facet%5D%5B%5D=Simple+Cone+Search&f%5Brights_facet%5D%5B%5D=To+the+extent+possible+under+law%2C+the+publisher+has+waived+all+copyright+and+related+or+neighboring+rights+to+the+catalogue+of+astrometric+++microlensing+events.++For+details%2C+see+the+%60Creative+Commons+CC0+1.0+Public+Domain+dedication+%3Chttp%3A%2F%2Fcreativecommons.org%2Fpublicdomain%2Fzero%2F1.0%2F%3E%60_.++Of+course%2C+you+should+still+give+proper+credit+when+using+this+data+as+required+by+good+scientific+practice.%0A%0A..+image%3A%3A+%2Fstatic%2Fimg%2Fcc0.png%0A+++%3Aalt%3A+%5BCC0%5D%0A%0A){kind=link}