J/AJ/168/288 VLASS stellar radio sources and Gaia counterparts (Ayanabha+, 2024)
Demography of stellar radio population within 500 pc: A VLASS-Gaia DR3 study.
Ayanabha D., Narang M., Puravankara M., Shridharan B., Tyagi H.,
Banerjee B., Nayak P.K., Surya A.
<Astron. J., 168, 288 (2024)>
=2024AJ....168..288A 2024AJ....168..288A
ADC_Keywords: Radio continuum; Radio sources; Cross identifications;
Stars, radio; Positional data; Optical; Photometry
Keywords: Radio continuum emission ; Stellar magnetic fields ;
Radio source catalogs ; Stellar properties ; Gaia ; Radio astronomy
Abstract:
In this work, we have carried out a systematic analysis of the Very
Large Array Sky Survey (VLASS) quick look catalogs together with Gaia
DR3 to identify the optical counterparts of 3GHz radio emitters within
500pc to obtain a homogeneous statistical sample of stellar radio
sources. We have identified distinct populations of 3GHz emitters
across the Gaia DR3 color-magnitude diagram. We also present candidate
sources (transient, highly variable, or background artifacts) that can
be confirmed by follow-up observations. A majority of the detected
sources constitute main-sequence G-, K-, and M-type stars, including
ultracool dwarfs. Pinning down the origin of radio emission from these
populations can help us gain further insights into the origin of
stellar and planetary magnetic fields. By analyzing the variation of
brightness temperature of the sources with their spectral type, we
have tentatively associated possible emission mechanisms with
different object types. We inspected the correlation between quiescent
radio and X-ray emission for our sample, which can provide crucial
insights into the current understanding of the Gudel-Benz
relationship, which is essential for modeling steady radio emission
and coronal heating. This VLASS-Gaia DR3 analysis acts as a pilot
study for follow-up observations at multiple wavelengths to better
understand stellar structure, model flaring activities, and detect
radio emission caused by star-planet interactions.
Description:
Very Large Array Survey (VLASS) is a National Radio Astronomy
Observatory (NRAO) initiative to carry out a continuum survey of the
entire sky above a decl. of -40°, using the Karl G. Jansky Very
Large Array in B and BnA configuration at S band (2-4GHz). The
project, which was initiated in 2017 and is scheduled for completion
by 2024, encompasses three distinct epochs of observation, each
separated by an approximate interval of 32 months. The survey has rms
noise of 120uJy per epoch and an estimated 60uJy rms noise for the
three-epoch stacked images with an angular resolution of ∼2.5". Gaia
is an ESA all-sky survey mission that provides most precise
astrometric and spectrophotometric measurements for ∼1.7 billion stars
in the optical band.
In this work, we have crossmatched the Gaia Third Data Release (DR3)
catalog (Gaia Collab., 2023; I/355) and VLASS Epoch 1 & 2 Quick Look
(QL1 & QL2) catalogs (Gordon+, 2020; http://cirada.ca/vlasscatalogueql0)
to identify the optical counterparts of the 3 GHz radio sources within
500 pc using precise parallax measurement from Gaia DR3. The first
epoch of VLASS observations was carried out from 2017 September to
2019 July, and the second epoch was carried out from 2020 April to
2022 April. Thus, the mean epoch for VLASS QL1 is 2018.7 and that for
VLASS QL2 is 2021.33. The positions of Gaia DR3 sources, whose epoch
is J2016, were proper motion corrected to J2018.7 and J2021.33.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 181 605 Very Large Array Survey, Gaia DR3 coordinates, and
photometric information for radio sources analyzed
in this study along with their classified category
--------------------------------------------------------------------------------
See also:
B/simbad : Simbad objects catalogue (M.Wenger 2000)
I/357 : Gaia DR3 Part 3. Non-single stars (Gaia Collaboration, 2022)
IX/69 : XMM-Newton Serendipitous Source Cat. 4XMM-DR13 (Webb+, 2023)
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
J/A+AS/124/259 : Westerbork Northern Sky Survey I. (Rengelink+ 1997)
J/ApJ/701/535 : A sample of candidate radio stars (Kimball+, 2009)
J/A+A/549/A131 : Radio survey of ultracool dwarfs (Antonova+, 2013)
J/ApJS/208/9 : Intrinsic colors & temperatures of PMS stars (Pecaut+, 2013)
J/A+A/598/A78 : The GMRT 150MHz all-sky radio survey (Intema+, 2017)
J/AJ/154/224 : Transiting planets in young clusters from K2 (Rizzuto+, 2017)
J/A+A/598/A104 : LOFAR Two-metre Sky Survey (Shimwell+, 2017)
J/A+A/612/A96 : Spect. survey of youngest field stars II. (Frasca+, 2018)
J/ApJ/859/33 : GOBELINS. IV. VLBA obs. of Taurus (Galli+, 2018)
J/MNRAS/489/437 : Origin of stellar flares on M dwarfs with TESS (Doyle+, 2019)
J/A+A/649/A6 : Gaia Cat. of Nearby Stars - GCNS (Gaia collaboration, 2021)
J/other/PASA/41.84 : Sydney Radio Star Catalogue (Driessen+, 2024)
http://cirada.ca/vlasscatalogueql0 : VLASS Quick Look & Single Epoch Cat.
(Gordon+, 2020)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaDR3 Gaia DR3 identifier (I/355)
21- 33 F13.9 deg RAJ2000 VLASS right ascension (J2000)
35- 48 F14.10 deg DEJ2000 [-40/85.5] VLASS declination (J2000)
50- 62 F13.9 deg RAJ2016 Gaia DR3 right ascension (ICRS)
64- 78 F15.11 deg DEJ2016 [-40/85.5] Gaia DR3 declination (ICRS)
80- 84 F5.2 mag Gmag [2.8/20.1] Gaia DR3 G band (673nm) magnitude
86- 90 F5.2 mag BP-RP [-0.3/5.2]? Gaia DR3 (Blue-Red) passband
color
92- 97 F6.2 pc Dist [5.6/498.4] Distance
99-103 F5.2 mJy/beam Flux1 [0/54.3] First epoch flux density (2-4GHz)
105-110 F6.2 mJy/beam Flux2 [0/109.1] Second epoch flux density (2-4GHz)
112-140 A29 --- Simbad Simbad identifier
142-161 A20 --- Type Simbad object type (1)
163-181 A19 --- Category Category (2)
--------------------------------------------------------------------------------
Note (1): Object types as follows:
** = Double or multiple star (Interacting binaries and
close CPM systems); 7 occurrences
AGN = Active Galaxy Nucleus; 1 occurrence
Ae* = Herbig Ae/Be Star; 2 occurrences
BLLac = BL Lac; 1 occurrence
BYDraV* = BY Dra variable; 15 occurrences
Be* = Be star; 1 occurrence
Blazar_Candidate = Blazar candidate; 1 occurrence
CataclyV* = Cataclysmic binary; 1 occurrence
CataclyV*_Candidate = Cataclysmic binary candidate; 1 occurrence
Cepheid = Cepheid variable (Includes anomalous Cepheids);
1 occurrence
ChemPec* = Chemically peculiar star (includes metal-poor stars);
1 occurrence
ClassicalCep = Classical Cepheid variable (delta Cep type);
2 occurrences
EclBin = Eclipsing binary; 14 occurrences
including:
{Al*} Eclipsing Binary of Algol type
{bL*} Eclipsing Binary of beta Lyr type
{WU*} Eclipsing Binary of W UMa type
EclBin_Candidate = Eclisping binary candidate; 1 occurrence
Eruptive* = Eruptive variable (including {Fl*} Flare Star);
4 occurrences
HighPM* = High proper motion star (total proper motion ≥50mas/yr);
28 occurrences
LongPeriodV* = Long-period variable (AB*, RG*, or s*r. Includes L, SR,
and OSARG) or {sr*} Semi-regular variable
(check LP* and V* measurements); 3 occurrences
Low-Mass* = Low-mass star (M ~< 1 Msun); 15 occurrences
OrionV* = Orion variable; 12 occurrences
PulsV* = Pulsating variable (non LPV pulsating star) or star
showing Eclipses by its Planet (see EB* and V*
measurements); 5 occurrences
QSO = Quasar; 1 occurrence
QSO_Candidate = Quasar candidate; 2 occurrences
RSCVnV* = RS CVn variable; 50 occurrences
Radio = Radio source; 24 occurrences
RotV* = Rotating variable; 49 occurrences
SB* = Spectroscopic binary; 39 occurrences
Star = Star; 52 occurrences
Symbiotic* = Symbiotic star; 1 occurrence
TTauri* = T Tauri star (includes classical and weak-line T Tauri);
24 occurrences
TTauri*_Candidate = T tauri star candidate; 1 occurrence
Variable* = Variable star; 3 occurrences
WhiteDwarf = White dwarf (SpT like D and PG1159), {ZZ*} Pulsating
White Dwarf (Maintype = WD*, secondary type = Pu*), or
ELMWD=Extremely Low Mass White Dwarf (in binaries,
SpT like ELMD); 1 occurrence
WhiteDwarf_Candidate = White dwarf candidate; 1 occurrence
X = X-ray source; 1 occurrence
YSO = Young stellar object (pre-main sequence); 9 occurrences
YSO_Candidate = Young stellar object candidate; 10 occurrences
alf2CVnV* = alpha2 CVn variable (Ap stars; magnetic); 4 occurrences
Note (2): Categories as follows:
Candidate Transient = 198 occurrences
Candidate Variable = 14 occurrences
Confirmed = 393 occurrences
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Robin Leichtnam [CDS] 16-Sep-2025