II/360 Gaia DR2 x AllWISE catalogue (Marton+, 2019)
Identication of Young Stellar Object candidates in the Gaia DR2 x AllWISE
catalogue with machine learning methods.
Marton G., Abraham P., Szegedi-Elek E., Varga J., Kun M., Kospal A.,
Varga-Verebelyi E., Hodgkin S., Szabados L., Beck R., Kiss Cs.
<Mon. Not. R. Astron. Soc., 487, 2522-2537 (2019)>
=2019MNRAS.487.2522M 2019MNRAS.487.2522M
=2019yCat.2360....0M 2019yCat.2360....0M
ADC_Keywords: Surveys ; Photometry, G band ; Photometry, infrared ;
Cross identifications
Keywords: accretion, accretion discs - methods: data analysis -
methods: statistical - astronomical data bases: Gaia -
stars: evolution - stars: pre-main-sequence -
stars: variables: T Tauri, Herbig Ae/Be
Abstract:
The second Gaia Data Release (DR2) contains astrometric and
photometric data for more than 1.6 billion objects with mean Gaia G
magnitude <20.7, including many Young Stellar Objects (YSOs) in
different evolutionary stages. In order to explore the YSO population
of the Milky Way, we combined the Gaia DR2 database with WISE and
Planck measurements and made an all-sky probabilistic catalogue of
YSOs using machine learning techniques, such as Support Vector
Machines, Random Forests, or Neural Networks. Our input catalogue
contains 103 million objects from the DR2xAllWISE cross-match table.
We classified each object into four main classes: YSOs, extragalactic
objects, main-sequence stars and evolved stars. At a 90% prob- ability
threshold we identified 1 129 295 YSO candidates. To demonstrate the
quality and potential of our YSO catalogue, here we present two
applications of it. (1) We explore the 3D structure of the Orion A
star forming complex and show that the spatial distribution of the
YSOs classified by our procedure is in agreement with recent results
from the literature. (2) We use our catalogue to classify published
Gaia Science Alerts. As Gaia measures the sources at multiple epochs,
it can efficiently discover transient events, including sudden
brightness changes of YSOs caused by dynamic processes of their
circumstellar disk. However, in many cases the physical nature of the
published alert sources are not known. A cross-check with our new
catalogue shows that about 30% more of the published Gaia alerts can
most likely be attributed to YSO activity. The catalogue can be also
useful to identify YSOs among future Gaia alerts.
Description:
We presented a classification of those sources in the Gaia DR2
catalogue that have a counterpart in the All-WISE catalogue.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.sam 331 1000 Gaia DR2 X AllWise catalog sample
catalog.txt 331 101838724 Gaia DR2 X AllWise catalog
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
II/328 : AllWISE Data Release (Cutri+ 2013)
Byte-by-byte Description of file: catalog.sam
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Bytes Format Units Label Explanations
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1- 19 I19 --- Source Gaia DR2 source ID (gid)
21- 30 F10.6 deg RAdeg Barycentric right ascension (ICRS)
at Ep=2015.5 (ra)
32- 41 F10.6 deg DEdeg Barycentric declination (ICRS)
at Ep=2015.5 (dec)
43- 49 F7.5 --- LE Probability of the source being an evolved star
using all WISE bands (LE)
51- 57 F7.5 --- e_LE Error of the LE probability (LEerr)
59- 65 F7.5 --- LEG Probability of the source being an extragalactic
object using all WISE bands (LEG)
67- 73 F7.5 --- e_LEG Error of the LEG probability (LEGerr)
75- 81 F7.5 --- LMS Probability of the source being a main-sequence
star using all WISE bands (LMS)
83- 89 F7.5 --- e_LMS Error of the LMS probability (LMSerr)
91- 97 F7.5 --- LY Probability of the source being a YSO using
all WISE bands (LY)
99-105 F7.5 --- e_LY Error of the LY probability (LYerr)
107-115 F9.6 mag Gmag G-band mean magnitude (Vega) (gmean)
117-123 F7.5 --- tau 353GHz R2.01 Planck dust opacity value (tau)
125-143 A19 --- AllWISE AllWISE designation (wid)
145-154 F10.6 deg RAAdeg AllWISE Right ascension (J2000) (raw)
156-165 F10.6 deg DEAdeg AllWISE Declination (J2000) (decw)
168-173 F6.3 mag W1mag AllWISE W1 magnitude (W1mag)
175-180 F6.3 mag W2mag AllWISE W2 magnitude (W2mag)
183-188 F6.3 mag W3mag AllWISE W3 magnitude (W3mag)
190-195 F6.3 mag W4mag AllWISE W4 magnitude (W4mag)
198-203 F6.3 mag Jmag 2MASS J magnitude (Jmag)
206-211 F6.3 mag Hmag 2MASS H magnitude (Hmag)
214-219 F6.3 mag Kmag 2MASS K magnitude (Kmag)
221-225 F5.3 mag e_W1mag ?=- AllWISE W1 Magnitude error (e_W1mag)
227-231 F5.3 mag e_W2mag ?=- AllWISE W2 Magnitude error (e_W2mag)
233-237 F5.3 mag e_W3mag ?=- AllWISE W3 Magnitude error (e_W3mag)
239-243 F5.3 mag e_W4mag ?=- AllWISE W4 Magnitude error (e_W4mag)
245-249 F5.3 mag e_Jmag ?=- 2MASS J magnitude error (e_Jmag)
251-255 F5.3 mag e_Hmag ?=- 2MASS H magnitude error (e_Hmag)
257-261 F5.3 mag e_Kmag ?=- 2MASS K magnitude error (e_Kmag)
263-267 F5.3 --- R Probability that WISE W3 and W4 detections are
real (R)
269-275 F7.5 --- SE Probability of the source being an evolved star
without W3 and W4 WISE bands (SE)
277-283 F7.5 --- e_SE Error of the SE probability (SEerr)
285-291 F7.5 --- SEG Probability of the source being an extragalactic
object without W3 and W4 WISE bands (SEG)
293-299 F7.5 --- e_SEG Error of the SEG probability (SEGerr)
301-307 F7.5 --- SMS Probability of the source being a main-sequence
star without W3 and W4 WISE bands (SMS)
309-315 F7.5 --- e_SMS Error of the SMS probability (SMSerr)
317-323 F7.5 --- SY Probability of the source being a YSO without
W3 and W4 WISE bands (SY)
325-331 F7.5 --- e_SY Error of the SY probability (SYerr)
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Acknowledgements:
Gabor Marton, marton.gabor(at)csfk.mta.hu
(End) Patricia Vannier [CDS] 24-May-2019