J/A+A/694/A250 Bow shocks around runaway stars (Carretero-Castrillo+, 2025)
New stellar bow shocks and bubbles found around runaway stars.
Carretero-Castrillo M., Benaglia P., Paredes J.M., Ribo M.
<Astron. Astrophys. 694, A250 (2025)>
=2025A&A...694A.250C 2025A&A...694A.250C (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Stars, Be ; Stars, O ; Stars, high-velocity ;
Space velocities ; Proper motions ; Infrared sources
Keywords: radiation mechanisms: nonthermal - radiation mechanisms: thermal -
starS: early-type - ISM: bubbles - infrared: ISM -
radio continuum: ISM
Abstract:
Runaway stars with peculiar high velocities can generate stellar bow
shocks. Only a few bow shocks show clear radio emission. Our goal is
to identify and characterize new stellar bow shocks around O and Be
runaway stars in the infrared (IR), as well as to study their possible
radio emission and nature. Our input data is a catalog of O and Be
runaways compiled using Gaia DR3. We used WISE IR images to search for
bow shock structures around these runaways, Gaia DR3 data to determine
the actual motion of the runaway stars corrected for interstellar
medium (ISM) motion caused by Galactic rotation, and archival radio
data to search for emission signatures. We finally explored the radio
detectability of these sources under thermal and nonthermal scenarios.
We found nine new stellar bow shock candidates, three new bubble
candidates, and one intermediate structure candidate. One of them is
an in situ bow shock candidate. We also found 17 already known bow
shocks in our sample, though we discarded one, and 62 miscellaneous
sources showing some IR emission around the runaways. We geometrically
characterized the sources in IR using the WISE-4 band and estimated
the ISM density at the bow shock positions, obtaining median values of
∼6 and ∼4cm-3 using 2D and 3D peculiar velocities, respectively.
Most of the new discovered bow shocks come from new runaway
discoveries. Within our samples we found that ∼24% of the O-type
runaway stars show bow shocks, while this decreases to ∼3% for Be-type
runaway stars. Two bow shocks present radio emission but not as clear
counterparts, and two others show hints of radio emission. The
physical scenarios indicate that two sources could still be compatible
with nonthermal radio emission. The new sample of O and Be runaway
stars allowed us to discover both new stellar bow shocks and bubbles.
Their geometrical characterization can be used to assess the physical
scenario of the radio emission. Deeper radio observations are needed
to unveil a population of radio-detected bow shocks, and the physical
scenarios occurring in these sources.
Description:
We present the proper motions corrected for the ISM motion caused by
Galactic rotation for the Galactic O and Be runaway stars found in
Carretero-Castrillo et al. (2023A&A...679A.109C 2023A&A...679A.109C, Cat. J/A+A/679/A109).
The proper motions were computed using Gaia DR3 data and the
prescription from Comeron & Pasquali (2007A&A...467L..23C 2007A&A...467L..23C). The table
also includes the previous bow shock reference for those sources that
were already known. In addition, we present different astrophysical
properties for the new and known stellar bow shocks and bubbles
identified using WISE and Gaia DR3 data: mass loss rates, wind
terminal velocities, radial velocities, peculiar velocities, the
geometrical characterization in WISE-4 band, and the ISM ambient
densities around the bow shock positions.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 200 106 Data of O runaway stars including corrected
proper motions
table2.dat 200 69 Data of Be runaway stars including corrected
proper motions
table4.dat 132 14 Data of new stellar bow shocks and bubbles
table5.dat 132 5 Data of some known stellar bow shocks and bubbles
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See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
J/A+A/679/A109 : GaiaDR3 Galactic runaway O, Be stars
(Carretero-Castrillo+, 2023)
Byte-by-byte Description of file: table1.dat table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Runaway Runaway star identifier (1)
7- 31 A25 --- Name Most common name of the star from the
GOSC (table 1) or BeSS (table 2) catalogs
33- 51 I19 --- GaiaDR3 Gaia DR3 source identifier
53- 54 I2 h RAh Gaia DR3 Right ascension (ICRS) at Ep=2016.0
56- 57 I2 min RAm Gaia DR3 Right ascension (ICRS) at Ep=2016.0
59- 64 F6.3 s RAs Gaia DR3 Right ascension (ICRS) at Ep=2016.0
66 A1 --- DE- Gaia DR3 Declination sign (ICRS)
at Ep=2016.0
68- 69 I2 deg DEd Gaia DR3 Declination (ICRS) at Ep=2016.0
71- 72 I2 arcmin DEm Gaia DR3 Declination (ICRS) at Ep=2016.0
74- 78 F5.2 arcsec DEs Gaia DR3 Declination (ICRS) at Ep=2016.0
80- 83 F4.2 kpc Dist Distance from the Sun (2)
85- 88 F4.2 kpc e_Dist Standard error of distance from the Sun (2)
90- 96 F7.3 mas/yr pmRAcosDEc Proper motion in right ascension direction
corrected for the ISM motion caused by
Galactic rotation
98-102 F5.3 mas/yr e_pmRAcosDEc Standard error of proper motion in right
ascension direction corrected for the ISM
motion caused by Galactic rotation
104-110 F7.3 mas/yr pmDEc Proper motion in declination direction
corrected for the ISM motion caused by
Galactic rotation
112-116 F5.3 mas/yr e_pmDEc Standard error of proper motion in
declination direction corrected for the ISM
motion caused by Galactic rotation
118-122 F5.2 mag Gmag G-band mean magnitude from Gaia DR3
124-130 A7 --- SpType Spectral Type from the GOSC catalog
132-136 F5.1 km/s Vpec2D Peculiar 2-dimensional (2D) velocity (2)
138-141 F4.1 km/s e_Vpec2D Standard error of peculiar 2D velocity (2)
143-146 F4.2 --- E Normalized significance of the runaway
nature of the star (2)
148-173 A26 --- RefRun Runaway reference in case the star had
already been reported as runaway (3)
175-200 A26 --- RefBow Bow shock reference in case the star had
already been reported as a stellar bow
shock (3)
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Note (1): GR1-GR106 in table1 (O runaway stars), BR1-BR69 in table2
(Be runaway stars).
Note (2): computed in Carretero-Castrillo+23
Note (3): References as follows:
Bekenstein and Bowers 1974 = Bekenstein & Bowers (1974ApJ...190..653B 1974ApJ...190..653B)
Boubert and Evans 2018 = Boubert & Evans (2018MNRAS.477.5261B 2018MNRAS.477.5261B)
Buren and McCray 1988 = Van Buren and McCray (1988ApJ...329L..93V 1988ApJ...329L..93V)
Colon et al. 1990 = Colon et al. (1990A&A...236..357C 1990A&A...236..357C)
Cruz-Gonzalez et al. 1974 = Cruz-gonzalez et al. (1974RMxAA...1..211C 1974RMxAA...1..211C,
Cat. III/84)
Gies 1987 = Gies & Bolton (1986ApJS...61..419G 1986ApJS...61..419G)
Hoogerwerf et al. 2001 = Hoogerwerf et al. (2001A&A...365...49H 2001A&A...365...49H)
Kobulnicky and Chick 2022 = Kobulnicky & Chick (2022AJ....164...86K 2022AJ....164...86K,
Cat. J/AJ/164/86)
Kobulnicky et al. 2016 = Kobulnicky et al. (2016ApJS..227...18K 2016ApJS..227...18K,
Cat. J/ApJS/227/18
Maiz Apellaniz et al. 2018 = Maiz-apellaniz et al. (2018A&A...616A.149M 2018A&A...616A.149M,
Cat. J/A+A/616/A149)
Mdzinarishvili 2004 = Mdzinarishvili (2004Ap.....47..155M 2004Ap.....47..155M)
Moutzouri et al. 2022 = Moutzouri et al. (2022A&A...663A..80M 2022A&A...663A..80M)
Peri et al. 2015 = Peri et al. (2015A&A...578A..45P 2015A&A...578A..45P,
Cat. J/A+A/578/A45)
Ribo et al. 2002 = Ribo et al. (2002A&A...384..954R 2002A&A...384..954R)
Tetzlaff et al. 2011 = Tetzlaff et al. (2011MNRAS.410..190T 2011MNRAS.410..190T,
Cat. J/MNRAS/410/190)
Van den Heuvel et al. 2000 = Van den Heuvel et al. (2000A&A...364..563V 2000A&A...364..563V)
Van der Buren et al. 1995 = Van Buren et al. (1995AJ....110.2914V 1995AJ....110.2914V)
Wit 2005 = de Wit et al. (2005A&A...437..247D 2005A&A...437..247D)
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Byte-by-byte Description of file: table4.dat table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 17 A17 --- Name Most common name of the star from the GOSC
catalog or BeSS database
19- 26 A8 --- SpType Spectral Type
28- 31 F4.2 Msun/yr dM/dt ?=- Mass-loss rates interpolated from
Vink & Sander (2021MNRAS.504.2051V 2021MNRAS.504.2051V)
33- 36 I4 km/s vterm ?=- Wind terminal velocities obtained from
Vink & Sander (2021MNRAS.504.2051V 2021MNRAS.504.2051V)
38- 42 F5.1 km/s RV ?=- Radial velocity
44- 69 A26 --- r_RV Radial velocity reference (1)
71- 74 F4.1 --- Vpec2D Peculiar 2D velocity computed in
Carretero-Castrillo et al.,
2023A&A...679A.109C 2023A&A...679A.109C, Cat. J/A+A/679/A109
76- 79 F4.1 --- Vpec3D ?=- Peculiar 3-dimensional (3D) velocity
computed in this work
81- 88 A8 --- BS/BU Bow shock (BS) or bubble (BU) identifier
90- 92 I3 arcsec Rarcsec ?=- Projected standoff-distance
94- 97 F4.2 pc Rpc ?=- Projected standoff-distance
99-101 I3 arcsec larcsec ?=- Projected length
103-106 F4.2 pc lpc ?=- Projected length
108-110 I3 arcsec warcsec Projected width
112-115 F4.2 pc wpc Projected width
117-120 F4.2 --- e ?=- Eccentricity of the ellipse used to
measure the bow shock
122-126 F5.1 cm-3 nISM2D ?=- ISM densities around the bow shock
position computed using Vpec2D
128-132 F5.1 cm-3 nISM3D ?=- ISM densities around the bow shock
position computed using Vpec3D
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Note (1): References as follows:
de Bruijne + Eilers (2012) = de Bruijne & Eilers (2012A&A...546A..61D 2012A&A...546A..61D,
Cat. J/A+A/546/A61
Kharchenko et al. (2007) = Kharchenko et al. (2007AN....328..889K 2007AN....328..889K,
Cat. J/AN/328/889 and III/254)
Kobulnicky + Chick (2022) = Kobulnicky & Chick (2022AJ....164...86K 2022AJ....164...86K,
Cat. J/AJ/164/86)
Williams et al. (2011) = Williams et al. (2011AJ....142..146W 2011AJ....142..146W,
Cat. J/AJ/142/146
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Acknowledgements:
Mar Carretero-Castrillo, mcarretero(at)fqa.ub.edu,
m.carretero.castrillo(at)gmail.com
(End) M. Carretero-Castrillo [Univ. de Barcelona], P. Vannier [CDS] 24-Jan-2025