J/ApJ/700/302 Relative photometry of XO-3 (Winn+, 2009)
On the spin-orbit misalignment of the XO-3 exoplanetary system.
Winn J.N., Johnson J.A., Fabrycky D., Howard A.W., Marcy G.W., Narita N.,
Crossfield I.J., Suto Y., Turner E.L., Esquerdo G., Holman M.J.
<Astrophys. J., 700, 302-308 (2009)>
=2009ApJ...700..302W 2009ApJ...700..302W
ADC_Keywords: Planets ; Photometry ; Stars, double and multiple
Keywords: planetary systems - planetary systems: formation - stars: individual
(XO-3, GSC 03727-01064) - stars: rotation
Abstract:
We present photometric and spectroscopic observations of the 2009
February 2 transit of the exoplanet XO-3b. The new data show that the
planetary orbital axis and stellar rotation axis are misaligned, as
reported earlier by Hebrard and coworkers. We find the angle between
the sky projections of the two axes to be 37.3±3.7deg, as compared
to the previously reported value of 70±15deg. The significance of
this discrepancy is unclear because there are indications of
systematic effects. XO-3b is the first exoplanet known to have a
highly inclined orbit relative to the equatorial plane of its parent
star, and as such it may fulfill the predictions of some scenarios for
the migration of massive planets into close-in orbits. We revisit the
statistical analysis of spin-orbit alignment in hot-Jupiter systems.
Assuming the stellar obliquities to be drawn from a single Rayleigh
distribution, we find the mode of the distribution to be
13+5-2deg. However, it remains the case that a model representing
two different migration channels-in which some planets are drawn
from a perfectly aligned distribution and the rest are drawn from an
isotropic distribution-is favored over a single Rayleigh
distribution.
Description:
We observed the transit of UT 2009 February 2 with the Keck I 10m
telescope on Mauna Kea, Hawaii. We used the High Resolution Echelle
Spectrometer (HIRES). Simultaneous photometric observations of the
2009 February 2 transit were conducted with the 1.2m telescope at the
Fred L. Whipple Observatory (FLWO) in Arizona, and the Nickel 1m
telescope at Lick Observatory in California.
Objects:
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RA (2000) DE Designation(s)
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04 21 52.7 +57 49 02 XO-3 = TYC 3727-1064-1
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 29 1408 Relative photometry of XO-3
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See also:
J/A+A/502/695 : Observations of HD 80606 planetary system (Pont+, 2009)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1 I1 --- Obs [1/2] Observatory code [1=r, 2=I] (1)
3- 15 F13.5 --- BJD Barycentric Julian Date of mid-observation
17- 22 F6.4 --- RFlux Relative flux
24- 29 F6.4 --- e_RFlux Error in RFlux
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Note (1): Code as follows:
1 = FLWO 1.2m telescope, r band;
2 = Nickel 1m telescope, I band.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 12-Jul-2011