J/A+A/661/A40 eRASS1 X-ray sources Sco-Cen members (Schmitt+, 2022)
X-raying the Sco-Cen OB association:
The low-mass stellar population revealed by eROSITA.
Schmitt J.H.M.M., Czesla S., Freund S., Robrade J., Schneider P.C.
<Astron. Astrophys. 661, A40 (2022)>
=2022A&A...661A..40S 2022A&A...661A..40S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, pre-main sequence ; X-ray sources
Keywords: stars: activity - stars: coronae - stars: low-mass - X-rays: stars
Abstract:
We present the results of the first X-ray all-sky survey (eRASS1)
performed by the eROSITA instrument on board the
Spectrum-Roentgen-Gamma (SRG) observatory of the Sco-Cen OB
association. Bona fide Sco-Cen member stars are young and are
therefore expected to emit X-rays at the saturation level. By
cross-correlating the eRASS1 source catalog with the Gaia EDR3
catalog, we arrive at a complete identification of the stellar (i.e.,
coronal) source content of eROSITA in the Sco-Cen association, and in
particular obtain for the first time a 3D view of the detected stellar
X-ray sources. Focusing on the low-mass population and placing the
optical counterparts identified in this way in a color-magnitude
diagram, we can isolate the young stars out of the detected X-ray
sources and obtain age estimates of the various Sco-Cen populations. A
joint analysis of the 2D and 3D space motions, the latter being
available only for a smaller subset of the detected stellar X-ray
sources, reveals that the space motions of the selected population
show a high degree of parallelism, but there is also an additional
population of young, X-ray emitting and essentially cospatial stars
that appears to be more diffuse in velocity space. Its nature is
currently unclear. We argue that with our procedures, an
identification of almost the whole stellar content of the Sco-Cen
association will become possible once the final Gaia and eROSITA
catalogs are available by the end of this decade.
Description:
Our Sco-Cen membership list is presented together with the X-ray
properties as obtained by a crossmatch with detections from the first
eROSITA all-sky survey (eRASS1) and the Gaia Early Data release EDR3.
In the catalog we provide a list with the corresponding (preliminary)
eROSITA designations, the designations of the matching Gaia EDR3
identifications, the derived X-ray right ascensions and declinations
(in degrees), the match distances (in arcsec) between eROSITA and Gaia
sources, the eRASS1 count rate (in cts/s) as well as a flag, denoting
which part of the Sco-Cen association the entry belongs to
(US,UCL,UCC).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 149 6190 Sco-Cen membership list with X-ray properties
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See also:
J/A+A/661/A1 : The eFEDS X-ray catalogs (V7.4) (Brunner+, 2022)
J/A+A/661/A2 : Galaxy clusters and groups in eFEDS (Liu+, 2022)
J/A+A/661/A3 : eFEDS counterparts to point-like sources (Salvato+, 2022)
J/A+A/661/A4 : eFEDS optical cluster and group catalog (Klein+, 2022)
J/A+A/661/A5 : The eFEDS AGN catalog (Liu+, 2022)
J/A+A/661/A7 : X-ray properties of eFEDS clusters and groups (Bahar+, 2022)
J/A+A/661/A8 : eFEDS catalogue of variable X-ray sources (Boller+, 2022)
J/A+A/661/A10 : eFEDS galaxy clusters and groups in disguise (Bulbul+, 2022)
J/A+A/661/A23 : Exoplanet X-ray irradiation & evaporation rates (Foster+, 2022)
J/A+A/661/A24 : Corona-chromosphere connection (Fuhrmeister+, 2022)
J/A+A/661/A29 : First eROSITA study of nearby M dwarfs (Magaudda+, 2022)
J/A+A/661/A34 : eta Cha cluster eROSITA X-ray scan (Robrade+, 2022)
J/A+A/661/A35 : eROSITA study of 47 Tuc globular cluster (Saeedi+, 2022)
J/A+A/661/A38 : SRG/ART-XC 1st year all-sky X-ray survey (Pavlinsky+, 2022)
J/A+A/661/A44 : A first eROSITA view of ultracool dwarfs (Stelzer+, 2022)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 23 A23 --- ERO eROSITA designation, 1eRASS JHHMMSS.s+DDMMSS
25- 43 I19 --- GaiaEDR3 Gaia EDR3 designation
45- 62 F18.14 deg RAdeg Right ascension (J2000.0)
64- 82 F19.15 deg DEdeg Declination (J2000.0)
84-104 F21.18 arcsec Matchdist [0.03/19.31] Matching distance between
eROSITA and Gaia sources
106-123 F18.16 --- Sprob [0/1] Stellar probability
125-145 F21.18 ct/s CRate eRASS1 count rate
147-149 A3 --- Group [LCC UCL US] Membership code (1)
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Note (1): Membership code as follows:
LCC = Lower-Centaurus-Crux
UCL = Upper-Centaurus-Lupus
US = Upper Scorpius
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Acknowledgements:
Jurgen Schmitt, jschmitt(at)hs.uni-hamburg.de
References:
The Early Data Release of eROSITA and Mikhail Pavlinsky ART-XC on the
SRG mission, 2022, A&A, 661, A1-A46
(End) Patricia Vannier [CDS] 12-Aug-2021