Astronomy and Astrophysics – Astronomy
Scientific paper
Jan 2011
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011aas...21730207c&link_type=abstract
American Astronomical Society, AAS Meeting #217, #302.07; Bulletin of the American Astronomical Society, Vol. 43, 2011
Astronomy and Astrophysics
Astronomy
Scientific paper
We report the detection of 24 um variations from the planet-hosting upsilon Andromedae system consistent with the orbital periodicity of the system's innermost planet, upsilon And b. Fitting a simple model with two hemispheres of constant surface brightness to our observations gives a peak-to-valley phase curve amplitude of 0.00130 times the mean system flux. Assuming a planetary radius of 1.3 RJup, this corresponds to a planetary temperature contrast of >900 K and an orbital inclination of >25 deg. We further report the largest phase offset yet observed for an extrasolar planet: the flux maximum occurs 80 deg before phase 0.5. Such a large phase offset is difficult to reconcile with most current atmospheric circulation models. We improve on earlier observations of this system in several important ways: (1) observations of a flux calibrator star demonstrate the MIPS detector is stable to 104 on long timescales, (2) we note that the background light varies systematically due to spacecraft operations, precluding use of this background as a flux calibrator (stellar flux measured above the background is not similarly affected), and (3) we calibrate for flux variability correlated with motion of the star on the MIPS detector. A reanalysis of our earlier observations of this system is consistent with our new result.
Cho James Y-K.
Crossfield Ian J. M.
Deming Drake
Hansen Brad M. S.
Harrington Joseph
No associations
LandOfFree
A New 24 micron Phase Curve for upsilon Andromedae b does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A New 24 micron Phase Curve for upsilon Andromedae b, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A New 24 micron Phase Curve for upsilon Andromedae b will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1400632