Exoclimes_Conference_booklet1

data reduction stage crucial to our current understanding of exoplanet atmospheres. This
has prompted the development of new, sophisticated techniques to robustly extract signals
from transit data, and also a drive to use new observing facilities to re-observe and confirm
exoplanet signals. Ground-based telescopes are now playing an increasingly prominent
role, with multi-object spectrographs enabling differential ground-based spectrophotometry.
These observations are now providing similar precision to space-based observations
where appropriate comparison stars are available, and should allow us to verify spacebased
spectra and ease our dependence on single instruments. Here, we present efforts
to measure transmission spectra using the Gemini telescopes, with the GMOS multi-object
spectrographs, and discuss how we extract the atmospheric signals in the presence of
complex noise sources. We report transit observations of WASP-29, HAT-P-32 and
(possibly) HAT-P-33, reaching sufficient precision to probe atmospheric features. These
reveal featureless spectra possibly caused by the presence of clouds in the upper
atmospheres, although further observations are required to confirm this.
On the Statistical Significance of Trends in Exoplanetary Emissions!
Joseph Harrington — University of Central Florida
We have examined the fluxes of exoplanetary atmospheres as measured during
secondary eclipses. Cowan and Agol (2011) and we (Harrington et al. 2007, 2010, 2011,
2012, 2013) have noted that at equilibrium temperatures above about 2000 K (zero
albedo, uniform redistribution), observed exoplanet fluxes are substantially higher than
even the elevated equilibrium temperature predicts. With a substantial increase in the
number of atmospheric flux measurements, we can now test the statistical significance of
this trend. We can also cast the data on a variety of axes to search further for the physics
behind both the jump in flux above about 2000 K and the wide scatter in fluxes at all
temperatures.
Enshrouded Close-In Exoplanets
Carole Haswell — Open University
Our near-UV HST observations of the extreme hot Jupiter WASP-12b revealed
extended exospheric gas overfilling the planet\s Roche lobe and causing
reproducible enhanced transit depths at 65 distinct wavelengths. There is
complete absorption, i.e. zero emergent flux, in the cores of the very strong
MgII h&k lines at all observed orbital phases.
I will present several lines of evidence to show this is due to diffuse gas lost
from WASP-12b, which enshrouds the entire planetary system. Our results suggest a new
interpretation of the known correlation between hot Jupiter atmosphere type and host star
activity as indicated by the cores of the very strong CaII H&K lines. I will present recent
observations of the putative evaporating rocky exoplanet KIC 1255b. WHT/ULTRACAM
simultaneous multiwavelength light curves obtained in July 2013 have implications for the
dust scattering function,an empirical upper limit on the size of the planet, and the limitcycle
mechanism which modulates the observed dust extinction. We used CFHT/
ESPaDOnS to perform transmission spectroscopy searching for metal rich vapour
expected to co-exist with the dust as the gas phase component of the planetary mass loss.
Finally I will discuss the general implications of these findings for the Galaxy’s population
of planets and for studies of star-planet interactions.
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