- ID:
- ivo://org.gavo.dc/gaia/s3/ssa
- Title:
- Gaia DR3 MC sampled XP spectra SSA
- Short Name:
- gdr3spec SSAP
- Date:
- 27 Dec 2024 08:31:12
- Publisher:
- The GAVO DC team
- Description:
- This is a re-publication the Gaia DR3 RP/BP spectra in the IVOA Spectral Data Model. It presents the continous spectra in sampled form, using a Monte Carlo scheme to decorrelate errors, elaborated in this resource's reference URL. The underlying tables are also available for querying through TAP, which opens some powerful methods for mass-analysing the data.
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- ID:
- ivo://CDS.VizieR/J/A+A/618/A93
- Title:
- Gaia DR2 open clusters in the Milky Way
- Short Name:
- J/A+A/618/A93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Open clusters are convenient probes of the structure and history of the Galactic disk. They are also fundamental to stellar evolution studies. The second Gaia data release contains precise astrometry at the submilliarcsecond level and homogeneous photometry at the mmag level, that can be used to characterise a large number of clusters over the entire sky. In this study we aim to establish a list of members and derive mean parameters, in particular distances, for as many clusters as possible, making use of Gaia data alone. We compiled a list of thousands of known or putative clusters from the literature. We then applied an unsupervised membership assignment code, UPMASK, to the Gaia DR2 (Cat. I/345) data contained within the fields of those clusters. We obtained a list of members and cluster parameters for 1229 clusters. As expected, the youngest clusters are seen to be tightly distributed near the Galactic plane and to trace the spiral arms of the Milky Way, while older objects are more uniformly distributed, deviate further from the plane, and tend to be located at larger Galactocentric distances. Thanks to the quality of Gaia DR2 astrometry, the fully homogeneous parameters derived in this study are the most precise to date. Furthermore, we report on the serendipitous discovery of 60 new open clusters in the fields analysed during this study.
- ID:
- ivo://CDS.VizieR/J/A+A/619/A180
- Title:
- Gaia DR2 photometric sensitivity curves
- Short Name:
- J/A+A/619/A180
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The second data release (DR2) from the European Space Agency mission Gaia took place on April 2018. DR2 included photometry for more than 1.3x10^9^ sources in the three bands G, G_BP_, and G_RP_. Even though the Gaia DR2 photometry is very precise, there are currently three alternative definitions of the sensitivity curves that show significative differences. The aim of this paper is to improve the quality of the input calibration data to produce new compatible definitions of the G, G_BP_, and G_RP_ bands and to identify the reasons for the discrepancies between previous definitions. We have searched the Hubble Space Telescope (HST) archive for Space Telescope Imaging Spectrograph (STIS) spectra with G430L+G750L data obtained with wide apertures and combined them with the CALSPEC library to produce a high quality spectral energy distribution (SED) library of 122 stars with a broad range of colors, including three very red stars. This library defines new sensitivity curves for G, G_BP_, and G_RP_ using a functional analytical formalism. The new sensitivity curves are significantly better than the two previous attempts we use as a reference, REV (Evans et al., 2018A&A...616A...4E, Cat. I/345) and WEI (Weiler, 2018A&A...617A.138W, Cat. J/A+A/617/A138). For G we confirm the existence of a systematic bias in magnitude and correct a color term present in REV. For G_BP_ we confirm the need to define two magnitude ranges with different sensitivity curves and measure the cut between them at G_phot_=10.87mag with a significant increase in precision. The new curves also fit the data better than either REV or WEI. For G_RP_, our new sensitivity curve fits the STIS spectra better and the differences with previous attempts reside in a systematic effect between ground-based and HST spectral libraries. Additional evidence from color-color diagrams indicate that the new sensitivity curve is more accurate. Nevertheless, there is still room for improvement in the accuracy of the sensitivity curves because of the current dearth of good-quality red calibrators: adding more to the sample should be a priority before Gaia data release 3 takes place.
- ID:
- ivo://CDS.VizieR/VII/285
- Title:
- Gaia DR2 quasar and galaxy classification
- Short Name:
- VII/285
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We provide probabilistic quasar and galaxy classifications for 2.7 million sources in Gaia Data Release 2. This has been achieved using a supervised classification method (Gaussian Mixture Models) based only on photometric and astrometric data (8 features) in Gaia-DR2. The model is trained empirically to classify objects into three classes - star, quasar, galaxy - for all objects with G>=14.5mag down to the Gaia magnitude limit of G=21.0mag. We provide the probabilities for being a quasar (pqso) and a galaxy (pgal); the probability of being a star is pstar = 1-(pqso+pgal), and all other Gaia data can be obtained by cross-matching Gaia-DR2 using the source identifier. As our main goal is to identify extragalactic objects, we only report objects with pqso+pgal>0.5. These probabilities incorporate a sensible class prior, namely that quasars are 500 times rarer than stars, and that galaxies 7500 times rarer than stars. See the paper for details of the purity and completeness of samples drawn from this catalogue, and for more details of its construction, contents, and validation.
- ID:
- ivo://CDS.VizieR/J/A+A/616/A7
- Title:
- Gaia DR2 radial velocity standard stars catalog
- Short Name:
- J/A+A/616/A7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Radial Velocity Spectrometer (RVS) on board the ESA satellite mission Gaia has no calibration device. Therefore, the radial velocity zero point needs to be calibrated with stars that are proved to be stable at a level of 300m/s during the Gaia observations. We compiled a dataset of ~71000 radial velocity measurements from five high-resolution spectrographs. A catalogue of 4813 stars was built by combining these individual measurements. The zero point was established using asteroids. The resulting catalogue has seven observations per star on average on a typical time baseline of 6yr, with a median standard deviation of 15m/s. A subset of the most stable stars fulfilling the RVS requirements was used to establish the radial velocity zero point provided in Gaia Data Release 2. The stars that were not used for calibration are used to validate the RVS data.
- ID:
- ivo://org.gavo.dc/gaia/s3/pub
- Title:
- Gaia DR3 RP/BP (XP) Monte Carlo sampled spectra
- Date:
- 06 Feb 2024 08:59:18
- Publisher:
- The GAVO DC team
- Description:
- This is a re-publication the Gaia DR3 RP/BP spectra in the IVOA Spectral Data Model. It presents the continous spectra in sampled form, using a Monte Carlo scheme to decorrelate errors, elaborated in this resource's reference URL. The underlying tables are also available for querying through TAP, which opens some powerful methods for mass-analysing the data.
- ID:
- ivo://xaovo/gaia/q3/dr3lite
- Title:
- Gaia DR3 source catalogue "light"
- Short Name:
- gaia.dr3lite
- Date:
- 25 Jun 2024 10:32:03
- Publisher:
- Xinjiang Astronomical Observatory,CAS
- Description:
- This is gaia_source from the Gaia Data Release 3, stripped to just enough columns to enable basic science (but therefore a bit faster and simpler to deal with than the full gaia_source table). Note that on this server, there is also The gedr3dist.main, which gives distances computed by Bailer-Jones et al. Use these in preference to working with the raw parallaxes. The full DR3 is available from numerous places in the VO (in particular from the TAP services ivo://uni-heidelberg.de/gaia/tap and ivo://esavo/gaia/tap).
- ID:
- ivo://org.gavo.dc/gaia/q3/dr3lite
- Title:
- Gaia DR3 source catalogue "light"
- Short Name:
- gaia.dr3lite
- Date:
- 27 Dec 2024 08:31:03
- Publisher:
- The GAVO DC team
- Description:
- This is gaia_source from the Gaia Data Release 3, stripped to just enough columns to enable basic science (but therefore a bit faster and simpler to deal with than the full gaia_source table). Note that on this server, there is also The gedr3dist.main, which gives distances computed by Bailer-Jones et al. Use these in preference to working with the raw parallaxes. This server also carries the gedr3mock schema containing a simulation of gaia_source based on a state-of-the-art galaxy model, computed by Rybizki et al. The full DR3 is available from numerous places in the VO (in particular from the TAP services ivo://uni-heidelberg.de/gaia/tap and ivo://esavo/gaia/tap).
- ID:
- ivo://org.gavo.dc/gaia/q2/dr2light
- Title:
- Gaia DR2 source catalogue "light"
- Short Name:
- gaia.dr2light
- Date:
- 27 Dec 2024 08:31:02
- Publisher:
- The GAVO DC team
- Description:
- This is a “light” version of the full Gaia DR2 gaia_source table, containing the original astrometric and photmetric columns with just enough additional information to let careful researchers notice when data is becomes uncertain and the full error model should be consulted. The full DR2 is available from numerous places in the VO (in particular from the TAP services ivo://uni-heidelberg.de/gaia/tap and ivo://esavo/gaia/tap). This table also includes a column containing the Renormalized Unit Weight Error RUWE (GAIA-C3-TN-LU-LL-124-01), a robust measure for the consistency of the solution. On this TAP service, there is the table gdr2dist.main containing distances computed by Bailer-Jones et al (:bibcode:`2018AJ....156...58B`). If in doubt, use these instead of the parallaxes provided here.
- ID:
- ivo://CDS.VizieR/J/A+A/616/A12
- Title:
- Gaia DR2 sources in GC and dSph
- Short Name:
- J/A+A/616/A12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The goal of this paper is to demonstrate the outstanding quality of the second data release of the Gaia mission and its power for constraining many different aspects of the dynamics of the satellites of the Milky Way. We focus here on determining the proper motions of 75 Galactic globular clusters, nine dwarf spheroidal galaxies, one ultra-faint system, and the Large and Small Magellanic Clouds. Using data extracted from the Gaia archive, we derived the proper motions and parallaxes for these systems, as well as their uncertainties. We demonstrate that the errors, statistical and systematic, are relatively well understood. We integrated the orbits of these objects in three different Galactic potentials, and characterised their properties. We present the derived proper motions, space velocities, and characteristic orbital parameters in various tables to facilitate their use by the astronomical community. Our limited and straightforward analyses have allowed us for example to (i) determine absolute and very precise proper motions for globular clusters; (ii) detect clear rotation signatures in the proper motions of at least five globular clusters; (iii) show that the satellites of the Milky Way are all on high-inclination orbits, but that they do not share a single plane of motion; (iv) derive a lower limit for the mass of the Milky Way of 9.8^+6.7^_-2.7_x10^11^M_{sun}_ based on the assumption that the Leo~I dwarf spheroidal is bound; (v) derive a rotation curve for the Large Magellanic Cloud based solely on proper motions that is competitive with line-of-sight velocity curves, now using many orders of magnitude more sources; and (vi) unveil the dynamical effect of the bar on the motions of stars in the Large Magellanic Cloud. All these results highlight the incredible power of the Gaia astrometric mission, and in particular of its second data release.