J/A+A/508/1313 Orion pre-main sequence RIJH light curves (Frasca+, 2009)
REM near-IR and optical photometric monitoring of pre-main sequence stars in
Orion. Rotation periods and starspot parameters.
Frasca A., Covino E., Spezzi L., Alcala J.M., Marilli E., Furesz G.,
Gandolfi D.
<Astron. Astrophys. 508, 1313 (2009)>
=2009A&A...508.1313F 2009A&A...508.1313F
ADC_Keywords: Associations, stellar ; Stars, pre-main sequence ;
Photometry, infrared
Keywords: stars: pre-main sequence - stars: rotation - stars: starspots -
stars: flare - techniques: photometric -
ISM: individual objects: Orion
Abstract:
We performed an intensive photometric monitoring of the PMS stars
falling in a field of about 10x10 arcminutes in the vicinity of the
Orion Nebula Cluster (ONC). Photometric data were collected between
November 2006 and January 2007 with the REM telescope in the VRIJHK'
bands. The largest number of observations is in the I band (about 2700
images) and in J and H bands (about 500 images in each filter). From
the observed rotational modulation, induced by the presence of surface
inhomogeneities, we derived the rotation periods for 16 stars and
improved previous determinations for the other 13.
The analysis of the spectral energy distributions and, for some stars,
of high-resolution spectra provided us with the main stellar
parameters (luminosity, effective temperature, mass, age, and vsini).
We also report the serendipitous detection of two strong flares in two
of these objects. In most cases, the light-curve amplitudes decrease
progressively from the R to H band as expected for cool starspots,
while in a few cases, they can only be modelled by the presence of hot
spots, presumably ascribable to magnetospheric accretion.
The application of our own spot model to the simultaneous light curves
in different bands allowed us to deduce the spot parameters and
particularly to disentangle the spot temperature and size effects on
the observed light curves.
Description:
The multiband (VRIJHK') photometry obtained with REM is presented in
Table 6. For a few stars, IRAC photometry in mid-IR bands (3.6, 4.5,
5.8, and 8.0 micron) from Rebull et al. (2006, Cat. J/ApJ/646/297)
is also listed. Table 7 lists the reference stars, along with their
parameters, used for the spectral classification and the determination
of effective temperature and projected rotational velocity (vsini) of
the targets. The files Ori_starXX.R, Ori_starXX.I, Ori_starXX.J,
Ori_starXX.H contain the photometric time series of the star XX in the
R, I, J, and H bands that are displayed in Figs. 4 and 22 of the
paper.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table6.dat 114 97 Standard VRIJHK' magnitudes
table7.dat 40 101 Reference stars with Elodie spectra used for the
spectral classification
lc/* . 110 Individual light curves
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See also:
J/ApJ/646/297 : Spitzer observations of pre-main-sequence stars (Rebull+, 2006)
Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq Identifier of the source
4- 19 A16 --- 2MASS 2MASS Identifier
21- 25 F5.2 mag Vmag ?=- V magnitude
27- 30 F4.2 mag e_Vmag ?=- V magnitude error
32- 36 F5.2 mag Rmag ?=- R magnitude
38- 41 F4.2 mag e_Rmag ?=- R magnitude error
43- 47 F5.2 mag Imag ?=- I magnitude
49- 52 F4.2 mag e_Imag ?=- I magnitude error
54- 58 F5.2 mag Jmag J magnitude
60- 63 F4.2 mag e_Jmag J magnitude error
65- 69 F5.2 mag Hmag H magnitude
71- 74 F4.2 mag e_Hmag H magnitude error
76- 80 F5.2 mag Kmag K magnitude
82- 85 F4.2 mag e_Kmag K magnitude error
87- 91 F5.2 mag [3.6] ?=- IRAC 3.6-micron magnitude (1)
93- 97 F5.2 mag [4.5] ?=- IRAC 4.5-micron magnitude (1)
99-103 F5.2 mag [5.8] ?=- IRAC 5.8-micron magnitude (1)
105-109 F5.2 mag [8.0] ?=- IRAC 8.0-micron magnitude (1)
111-114 A4 --- LC Bands(s) with available light curves in
subdirectory lc (2)
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Note (1): From Rebull et al. (2006, Cat. J/ApJ/646/297)
Note (2): File identified as Ori_starNN.B, where NN is the star number and
B the band.
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name Star Name
15- 22 A8 --- SpType Spectral Type
25- 28 I4 K Teff Effective temperature
30- 34 F5.2 [cm/s2] logg ?=- Surface gravity
36- 40 F5.2 --- [Fe/H] ?=- Metallicity
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Byte-by-byte Description of file (#): lc/*
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Bytes Format Units Label Explanations
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6- 18 F13.5 d HJD Heliocentric Julian Day
23- 29 F7.4 mag mag R, I, J or H magnitude
34- 39 F6.4 mag e_mag Magnitude error
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Acknowledgements:
Antonio Frasca, antonio.frasca(at)oact.inaf.it
(End) Antonio Frasca [INAF-OACt, Italy], Patricia Vannier [CDS] 05-Nov-2009