J/A+A/620/A128 Gaia DR2 study of Herbig Ae/Be stars (Vioque+, 2018)
Gaia DR2 study of Herbig Ae/Be stars.
Vioque M., Oudmaijer R.D., Baines D., Mendigutia I., Perez-Martinez R.
<Astron. Astrophys. 620, A128 (2018)>
=2018A&A...620A.128V 2018A&A...620A.128V (SIMBAD/NED BibCode)
ADC_Keywords: Stars, pre-main sequence ; Stars, emission ; Stars, Be ;
Effective temperatures ; Photometry ; Stars, distances ;
Stars, ages ; Stars, masses
Keywords: stars: variables: T-Tauri - stars: variables: Herbig Ae/Be -
Hertzsprung-Russell and C-M diagrams - stars: formation -
stars: pre-main sequence - stars: emission-line, Be - infrared: stars
Abstract:
We use Gaia Data Release 2 (DR2, Cat. I/345) to place 252 Herbig Ae/Be
stars in the HR diagram and investigate their characteristics and
properties.
For all known Herbig Ae/Be stars with parallaxes in Gaia DR2, we
collected their atmospheric parameters and photometric and extinction
values from the literature. To these data we added near- and
mid-infrared photometry, collected Halpha emission line properties
such as equivalent widths and line profiles, and their binarity
status. In addition, we developed a photometric variability indicator
from Gaia's DR2 information.
We provide masses, ages, luminosities, distances, photometric
variabilities and infrared excesses homogeneously derived for the most
complete sample of Herbig Ae/Be stars to date. We find that high mass
stars have a much smaller infrared excess and have much lower optical
variabilities compared to lower mass stars, with the break at around
7M☉. Halpha emission is generally correlated with infrared
excess, with the correlation being stronger for infrared emission at
wavelengths tracing the hot dust closest to the star. The variability
indicator as developed by us shows that approximately 25% of all
Herbig Ae/Be stars are strongly variable. We observe that the strongly
variable objects display doubly peaked Halpha line profiles,
indicating an edge-on disk.
The fraction of strongly variable Herbig Ae stars is close to that
found for A-type UX Ori stars. It had been suggested that this
variability is in most cases due to asymmetric dusty disk structures
seen edge-on. The observation here is in strong support of this
hypothesis. Finally, the difference in dust properties occurs at
7M☉, while various properties traced at UV/optical wavelengths
differ at a lower mass, 3M☉. The latter has been linked to different
accretion mechanisms at work whereas the differing infrared properties
and photometric variabilities are related to different or differently
acting (dust-)disk dispersal mechanisms.
Description:
There are two tables. The one called "hqsample" for high-quality
sample contains the 218 Herbig Ae/Be stars with Gaia DR2 parallaxes
that are astrometrically well behaved. In general, this means that
they satisfy Equation 1 of the paper (or Equation C.2 of Lindegren et
al., 2018A&A...616A...2L 2018A&A...616A...2L, Cat. I/345). We also excluded from this
sample the objects that are placed in unrealistic positions on the HR
diagram. The other 34 Herbig Ae/Be stars that have Gaia DR2 parallaxes
but do not satisfy the previous conditions are presented in the other
table called "lqsample" for low-quality sample. We refer to the paper
for more details.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
hqsample.dat 346 218 Main parameters of each Herbig Ae/Be star belonging
to the high quality sample of 218 sources (table 1)
hqsample.fits 2880 31 Fits version of hqsample table
lqsample.dat 346 34 Main parameters of each Herbig Ae/Be star belonging
to the low quality sample of 34 sources (table 2)
lqsample.fits 2880 11 Fits version of lqsample table
refs.dat 132 69 References
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/A+A/620/A127 : Cassification of RR Lyrae and Cepheid (Molnar+, 2018)
Byte-by-byte Description of file: hqsample.dat lqsample.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- Name Name of the Herbig Ae/Be star
15- 16 I2 h RAh Right ascension from Gaia DR2
(ICRS at epoch 2015.5)
18- 19 I2 min RAm Right ascension from Gaia DR2
(ICRS at epoch 2015.5)
21- 24 F4.1 s RAs Right ascension from Gaia DR2
(ICRS at epoch 2015.5)
26 A1 --- DE- Declination sign from Gaia DR2
(ICRS at epoch 2015.5)
27- 28 I2 deg DEd Declination from Gaia DR2
(ICRS at epoch 2015.5)
30- 31 I2 arcmin DEm Declination from Gaia DR2
(ICRS at epoch 2015.5)
33- 34 I2 arcsec DEs Declination from Gaia DR2
(ICRS at epoch 2015.5)
36- 44 F9.6 mas plx Parallax from Gaia DR2
46- 53 F8.6 mas e_plx Parallax uncertainty from Gaia DR2
55- 60 F6.1 pc Dist Distance derived using an exponentially
decreasing density prior
62- 66 F5.1 pc E_Dist Upper error on the Distance, to the 95th
percentile confidence interval on the
Distance estimate
68- 72 F5.1 pc e_Dist Lower error on the Distance, to the 5th
percentile confidence interval on the
Distance estimate
74- 78 I5 K Teff Effective temperature from the literature (1)
80- 83 I4 K E_Teff Upper error of Teff
85- 88 I4 K e_Teff Lower error of Teff
90- 94 F5.2 [Lsun] LogL Decimal logarithm of the luminosity
96- 99 F4.2 [Lsun] E_LogL Upper error of LogL
101-104 F4.2 [Lsun] e_LogL Lower error of LogL
106-111 F6.3 mag Av Total extinction (1)
113-118 F6.3 mag E_Av Upper error of Av
120-125 F6.3 mag e_Av Lower error of Av
127-131 F5.2 mag V Johnson V band magnitude (1)
133-135 A3 --- Bin [Yes ] Binarity status: "Yes" if the source
has been classified as binary,
nothing otherwise
137-138 I2 --- r_Bin ?=- References for Binary column
(in ref.dat file)
140-148 E9.4 --- E(NIR) ?=- Infrared excess in the 1.24-3.4um
interval. Derived following Equation 2 of
the paper
150-158 E9.4 --- E_E(NIR) ?=- Upper error of NearIRexcess
160-168 E9.4 --- e_E(NIR) ?=- Lower error of NearIRexcess
170-178 E9.4 --- E(MIR) ?=- Infrared excess in the 3.4-22um
interval. Derived following Equation 2 of
the paper
180-188 E9.4 --- E_E(MIR) ?=- Upper error of MidIRexcess
190-198 E9.4 --- e_E(MIR) ?=- Lower error of MidIRexcess
200-207 F8.3 0.1nm EWHa ?=- Halpha equivalent width, from the
literature. Negative numbers indicate
emission
209-214 F6.3 0.1nm e_EWHa ?=- Uncertainty of EWHa, from the literature
216-217 I2 --- r_EWHa ?=- References for EWHa and e_EWHa columns
(in refs.dat file)
219 A1 --- Hashape Line profile of the Halpha line, from
the literature (2)
221-222 I2 --- r_Hashape ?=- References for Hashape
(in refs.dat file)
224-228 F5.2 --- Vi ?=- Variability indicator. Derived following
Equation 4 of the paper (3)
230-232 A3 --- UXOR [Yes ] UXOR status: "Yes" if the source has
been classified as UXOR type,
nothing otherwise
234-239 F6.3 Msun Mass ?=- Mass of the source
241-246 F6.3 Msun E_Mass ?=- Upper error of the Mass
248-253 F6.3 Msun e_Mass ?=- Lower error of the Mass
255-263 E9.4 Myr Age ?=- Age of the source
265-273 E9.4 Myr E_Age ?=- Upper error of the Age
275-283 E9.4 Myr e_Age ?=- Lower error of the Age
285-289 F5.2 --- E(J) ?=- Infrared excess at the J band (1.24um) (4)
291-296 F6.2 --- E(H) ?=- Infrared excess at the H band (1.66um) (4)
298-304 F7.2 --- E(Ks) ?=- Infrared excess at the
Ks band (2.16um) (4)
306-312 F7.2 --- E(W1) ?=- Infrared excess at the W1 band (3.4um) (4)
314-321 F8.2 --- E(W2) ?=- Infrared excess at the W2 band (4.6um) (4)
323-331 F9.2 --- E(W3) ?=- Infrared excess at the W3 band (12um) (4)
333-342 F10.2 --- E(W4) ?=- Infrared excess at the W4 band (22um) (4)
344-346 A3 --- The [Yes ] Yes if the source appears in Table 1
of The et al. (1994A&AS..104..315T 1994A&AS..104..315T),
nothing otherwise
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Note (1): Atmospheric parameters Teff, AV and V taken from the following
sources in order of choice:
Fairlamb et al., 2015MNRAS.453..976F 2015MNRAS.453..976F; Montesinos et al., 2009A&A...495..901M 2009A&A...495..901M;
Hernandez et al., 2004AJ....127.1682H 2004AJ....127.1682H; Mendigutia et al., 2012A&A...543A..59M 2012A&A...543A..59M;
Carmona et al., 2010A&A...517A..67C 2010A&A...517A..67C; Chen et al., 2016NewA...44....1C 2016NewA...44....1C;
Alecian et al., 2013MNRAS.429.1001A 2013MNRAS.429.1001A; Sartori et al., 2010AJ....139...27S 2010AJ....139...27S;
Manoj et al., 2006ApJ...653..657M 2006ApJ...653..657M; Hernandez et al., 2005AJ....129..856H 2005AJ....129..856H;
Vieira et al., 2003AJ....126.2971V 2003AJ....126.2971V; APASS Data Release 9 (cat. II/336) and
the SIMBAD database.
If not available they were derived as described in Sect. 2.2.
See Sect. 3 for derivation of L, Mass and Age.
Note (2): Classification as follows:
s = single-peaked
d = double-peaked
P = P-Cygni profile, both regular or inverse
Note (3): in low-quality sample, variability indicator values (Vi) for these
objects could not be derived as they are not astrometrically well behaved.
Similarly, many of these sources fall outside the Pre-Main Sequence tracks
and isochrones in the HR diagram and no masses or ages could be derived for
them. We decided to present the masses and ages in the cases they were
computable but these values have to be taken with caution.
Note (4): Infrared excess at individual bandpasses is defined as Fobserved/FCK,
being Fobserved the dereddened observed monochromatic flux and FCK the
expected flux according to the Castelli-Kurucz model
(Castelli & Kurucz, 2004, arXiv:astro-ph/0405087).
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Ref Reference number
4- 22 A19 --- BibCode BibCode
24- 56 A33 --- Aut Author's name
58-132 A75 --- Com Comments
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Acknowledgements:
Miguel Vioque, miguel.vioque(at)gmail.com
(End) Miguel Vioque [Univ. of Leeds, UK], Patricia Vannier [CDS] 06-Aug-2018