J/AJ/142/60 Palomar Transient Factory Orion Project (Van Eyken+, 2011)
The Palomar Transient Factory Orion Project:
eclipsing binaries and young stellar objects.
Van Eyken J.C., Ciardi D.R., Rebull L.M., Stauffer J.R., Akeson R.L.,
Beichman C.A., Boden A.F., Von Braun K., Gelino D.M., Hoard D.W.,
Howell S.B., Kane S.R., Plavchan P., Ramirez S.V., Bloom J.S., Cenko S.B.,
Kasliwal M.M., Kulkarni S.R., Law N.M., Nugent P.E., Ofek E.O.,
Poznanski D., Quimby R.M., Grillmair C.J., Laher R., Levitan D.,
Mattingly S., Surace J.A.
<Astron. J., 142, 60 (2011)>
=2011AJ....142...60V 2011AJ....142...60V
ADC_Keywords: Clusters, open ; Binaries, eclipsing ; YSOs ; Photometry, infrared
Keywords: binaries: close - binaries: eclipsing -
open clusters and associations: individual (25 Ori) -
planets and satellites: detection - stars: pre-main sequence -
techniques: photometric
Abstract:
The Palomar Transient Factory (PTF) Orion project is one of the
experiments within the broader PTF survey, a systematic automated
exploration of the sky for optical transients. Taking advantage of the
wide (3.5°x2.3°) field of view available using the PTF camera
installed at the Palomar 48 inch telescope, 40 nights were dedicated
in 2009 December to 2010 January to perform continuous high-cadence
differential photometry on a single field containing the young
(7-10Myr) 25 Ori association. Little is known empirically about the
formation of planets at these young ages, and the primary motivation
for the project is to search for planets around young stars in this
region. The unique data set also provides for much ancillary science.
In this first paper, we describe the survey and the data reduction
pipeline, and present some initial results from an inspection of the
most clearly varying stars relating to two of the ancillary science
objectives: detection of eclipsing binaries and young stellar objects.
Description:
Data were taken for the Orion project on the majority of the clear
nights between 2009 December 1 and 2010 January 15. Weather
permitting, the chosen primary field was observed in the R filter as
near to continuously as possible, whenever it was higher in the sky
than an airmass of 2.0. Exposures were 30s long, with a cadence
varying generally between 70 and 90s, including readout time and
depending on the performance of the telescope control system and
guiding control loop.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 142 82 New eclipsing binaries from the PTF Orion data
table3.dat 188 16 Candidate CTTSs: sources with irregular light
curves and ΔR∼1.0mag or more
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See also:
J/AJ/129/907 : New Ori OB1 members (Briceno+, 2005)
J/ApJ/661/1119 : Spectroscopy in the 25 Ori group (Briceno+, 2007)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 I1 --- Type [1/5] Classification of star (1)
3- 10 A8 --- Name Star designation <[VCR2011] NN-NNNN> in Simbad
11- 13 A3 --- n_Name Individual notes (2)
15- 22 F8.5 deg RAdeg Right ascension in decimal degrees (J2000)
24- 30 F7.5 deg DEdeg Declination in decimal degrees (J2000)
32- 48 A17 --- OName 2MASS/USNOB1.0 designation (G1)
50- 54 F5.2 mag Jmag ?=- 2MASS J magnitude
56- 59 F4.2 mag e_Jmag ? rms uncertainty on Jmag
61 A1 --- l_Hmag Limit flag on Hmag
62- 66 F5.2 mag Hmag ?=- 2MASS H magnitude
68- 71 F4.2 mag e_Hmag ? rms uncertainty on Hmag
73 A1 --- l_Ksmag Limit flag on Ksmag
74- 78 F5.2 mag Ksmag ?=- 2MASS Ks magnitude
80- 83 F4.2 mag e_Ksmag ? rms uncertainty on Ksmag
85 A1 --- Cl [DC] Classification, Close or Detached
87- 94 F8.6 d Per ?=- Period
96-103 F8.6 d e_Per ? rms uncertainty on Per
105-113 F9.5 d T0 Heliocentric Julian date for the epoch of the
primary eclipse T0 (HJD-2455000)
115-121 F7.5 d e_T0 rms uncertainty on T0
123-126 I4 pc Dist ?=- Estimated distance to the system (3)
128-131 I4 pc e_Dist ? rms uncertainty on Dist
133-137 F5.2 mag Rmag Median-measured R magnitude
139-142 F4.2 mag dR Approximate peak-to-peak magnitude range
ΔR of the measured light curve
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Note (1): Classification as follows:
1 = Pre-main-sequence low-mass binary candidates
2 = Other low-mass candidates
3 = Pre-main-sequence close-binary candidates
4 = Other binaries of interest
5 = Other binaries
Note (2): Note on Name as follows:
a = Only one eclipse obtained - period indeterminate.
b = Partial coverage of only one (presumed) eclipse obtained - period
indeterminate, T0 not well constrained.
c = T0 not well determined due to incomplete coverage of eclipse.
Measurement error may be unreliable.
d = Only one (very good) eclipse observed; period based on out-of-eclipse
variation.
e = Unusual light curve, possible semi-detached system. Listed distance is
assuming a contact binary, but using a detached-system distance estimate
yields a distance of 268±64pc - see Section 5.4.3.
f = Very short period W UMa system - see Section 5.4.4.
g = Used center of secondary eclipse for T0, owing to poor coverage of
primary.
h = Three clear eclipses, but unable to find coherent period - possible
triple system?
i = Nearby second source in USNO-B; chance of slight contamination.
j = Secondary eclipse not evident, or primary and secondary eclipses
indistinguishable - possible factor of two ambiguity in P.
k = Only two eclipses obtained - period ambiguous.
l = Apparent pulsating binary - short-period oscillations seen, with ∼1/2hr
period. See Section 5.4.4.
m = Somewhat distorted light curve shape - may actually represent stellar
pulsations rather than a binary system (D. Bradstreet 2010, private
communication).
n = See Section 4.2 for a discussion of zero-point accuracy.
o = Identified as a candidate variable star by Kraus et al.
(2007, Cat. J/AJ/134/1488).
Note (3): Distance estimates are omitted in cases where 2MASS magnitudes
reported are limits only.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name Star designation [VCR2011] NN-NNNN in Simbad
9 A1 --- n_Name [a-c] Individual notes (1)
11- 18 F8.5 deg RAdeg Right ascension in decimal degrees (J2000)
20- 26 F7.5 deg DEdeg Declination in decimal degrees (J2000)
28- 44 A17 --- OName 2MASS/USNOB1.0 designation (G1)
45- 49 F5.1 mas/yr pmRA Proper motion along right ascension
51- 54 F4.1 mas/yr e_pmRA rms uncertainty on pmRA
56- 60 F5.1 mas/yr pmDE Proper motion along declination
62- 65 F4.1 mas/yr e_pmDE rms uncertainty on pmDE
67- 71 F5.2 mag Rmag Median-measured R magnitude
73- 76 F4.2 mag dR Approximate peak-to-peak magnitude range
ΔR of the measured light curve
78- 81 F4.2 mag e_Rmag rms uncertainty on Rmag
83- 87 F5.2 mag Jmag 2MASS J magnitude (2)
89- 92 F4.2 mag e_Jmag rms uncertainty on Jmag
94- 98 F5.2 mag Hmag 2MASS H magnitude (2)
100-103 F4.2 mag e_Hmag ? rms uncertainty on Hmag
105-109 F5.2 mag Ksmag 2MASS Ks magnitude (2)
111-114 F4.2 mag e_Ksmag ? rms uncertainty on Ksmag
116-120 F5.2 mag [3.6] ? Spitzer-IRAC 3.6um magnitude
122-125 F4.2 mag e_[3.6] ? rms uncertainty on [3.6]
127-131 F5.2 mag [4.5] ? Spitzer-IRAC 4.5um magnitude
133-136 F4.2 mag e_[4.5] ? rms uncertainty on [4.5]
138-142 F5.2 mag [5.8] ? Spitzer-IRAC 5.8um magnitude
144-147 F4.2 mag e_[5.8] ? rms uncertainty on [5.8]
149-153 F5.2 mag [8.0] ? Spitzer-IRAC 8.0um magnitude
155-158 F4.2 mag e_[8.0] ? rms uncertainty on [8.0]
160-163 F4.2 mag [24] ? Spitzer-IRAC 24um magnitude
165-168 F4.2 mag e_[24] ? rms uncertainty on [24]
170-173 F4.2 mag Ks-[24] ? Ks-[3.6] colour index
175-178 F4.2 mag e_Ks-[24] ? rms uncertainty on Ks-[24]
180-183 F4.2 mag [3.6]-[24] ? [3.6]-[24] colour index
185-188 F4.2 mag e_[3.6]-[24] ? rms uncertainty on [3.6]-[24]
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Note (1): Notes as follows:
a = Known CTTS CVSO 35 (Briceno et al. 2005, Cat. J/AJ/129/907;
2007, Cat. J/ApJ/661/1119)
b = Reported as a candidate WTTS by McGehee (2006, Cat. J/AJ/131/2959)
(SDSS J052700.12+010136.8)
c = Resembles the "dipper" objects discussed by Morales-Calderon et al.
(2011ApJ...733...50M 2011ApJ...733...50M)
d = See Section 4.2 for a discussion of zero-point accuracy.
Note (2): 2MASS quality flag is "A" in all three bands for all sources
(see Section 2.3).
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Global notes:
Note (G1): Where possible the matched 2MASS identifier is given based on the
J2000 source coordinates; in cases where no 2MASS match was found, the
corresponding USNO-B1.0 match running-number-based ID is given instead, with
the format "NNNN-NNNNNNNN" (with no preceding "J").
Full PTF survey catalog IDs can be constructed based on these coordinates,
using the format "PTF1 JHHMMSS.ss+DDMMSS.s." Since precision astrometry was
not the primary goal of the PTF Orion project, it is preferable to use
2MASS/USNO-B1.0 coordinates for this purpose rather than our PTF Orion
measured coordinates.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 12-Oct-2012