J/AJ/166/23 OB-stars observed at 1450MHz (Huang+, 2023)
Estimation of the Flux at 1450MHz of OB Stars for FAST and SKA.
Huang Q., Jiang B., Deng D., Yu B., Zijlstra A.
<Astron. J., 166, 23 (2023)>
=2023AJ....166...23H 2023AJ....166...23H
ADC_Keywords: Stars, OB; Spectra, radio; Parallaxes, trigonometric;
Effective temperatures; Stars, masses
Keywords: OB stars ; Radio continuum emission ; Stellar winds ; Radio
telescopes
Abstract:
Radio observation is crucial to understanding the wind mechanism of OB
stars but very scarce. This work estimates the flux at 1450MHz
(S1.4GHz) of about 5000 OB stars identified by the LAMOST
spectroscopic survey and confirmed by the Gaia astrometric as well as
astrophysical measurements. The calculation is performed under the
free-free emission mechanism for wind with the mass-loss rate derived
from stellar parameters. The estimated S1.4GHz distributes from
10-11 to 10-3Jy with the peak at about 10-8Jy. This implies that
the complete SKA-II can detect more than half of them, and some tens
of objects are detectable by FAST without considering source
confusion. An array of FAST would increase the detectable sample by 2
orders of magnitude.
Description:
Radio observations of OB stars have been conducted by some groups.
Isequilla+, 2019A+A...627A..58I 2019A+A...627A..58I observed the Cygnus OB2 and OB8
regions by the Giant Metrewave Radio Telescope, and detected nine
young massive stars that have the flux at 325MHz and 610MHz above
2mJy. Previously, Kennedy+, 2010ApJ...709..632K 2010ApJ...709..632K examined 50
observations across frequencies between 1.4 GHz and 43 GHz using the
Very Large Array (VLA) to observe the Cygnus OB2 No.5 system.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 146 4930 The S1.4GHz brightest OB stars
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See also:
I/352 : Distances to 1.47 billion stars in Gaia EDR3 (Bailer-Jones+, 2021)
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
V/146 : LAMOST DR1 catalogs (Luo+, 2015)
J/AJ/149/131 : Parameters galactic nearby main-sequence stars (Eker+, 2015)
J/MNRAS/484/1838 : Spatial substructure of Cygnus OB2 (Berlanas+, 2019)
J/MNRAS/495/2738 : Luminosities 34 slowly pulsating B stars (Pedersen+, 2020)
J/ApJS/257/54 : Early-type star param. from LAMOST LRS & MRS (Guo+, 2021)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- ID [0/4929] Internal index number
6- 13 F8.4 deg RAdeg [0/360] Right Ascension (J2000)
15- 21 F7.4 deg DEdeg [-10/66] Declination (J2000)
23- 26 F4.2 10+4K Teff [1.25/4.1] Effective temperature
28- 31 F4.2 [cm/s2] logg [2.5/4.6] log surface gravity
33- 38 F6.4 mas plx [0.07/2.93] Gaia DR3 parallax
40- 43 I4 pc Dist [339/9400] Distance
45- 50 F6.3 mag Bpmag [4.29/16.1] Gaia DR3 Blue passband magnitude
52- 57 F6.3 mag Rpmag [4.48/15.8] Gaia DR3 Red passband magnitude
59- 63 F5.3 mag ABp [0/8.44] Extinction in Gaia DR3 Blue passband
65- 69 F5.3 mag ARp [0/4.85] Extinction in Gaia DR3 Red passband
71- 76 F6.3 mag Bp0mag [4.29/15.1] Extinction corrected Gaia DR3 Blue
passband magnitude
78- 83 F6.3 mag Rp0mag [4.48/15.3] Extinction corrected Gaia DR3 Red
passband magnitude
85- 90 F6.3 mag (Bp-Rp)0 [-0.5/-0.1] Extinction correct Bp-Rp color
92- 97 F6.3 mag BpMAG [-6.35/1.92] Absolute Gaia DR3 Blue passband
magnitude
99-104 F6.3 mag RpMAG [-6.02/2.16] Absolute Gaia DR3 Red passband
magnitude
106-109 F4.1 solMass Mass [4.2/82.3] Stellar mass
111-117 I7 solLum Lum [377/2881346] Stellar luminosity
119-127 F9.2 --- Mdot [0.16/628527] Mass loss rate, 10-6xM☉/yr
129-139 F11.3 nJy Flux [0.002/1550650] Estimated flux at 1450 MHz
141-146 F6.3 mag BC [-6.15/-3.41] Bolometric magnitude
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 02-Feb-2024