The discovery paper of a new exoplanet from the K2 C4 field submited by Alexandre Santerne is in the arxiv.
http://arxiv.org/abs/1601.07680
My colaboration started with a request from Alex to observe this target in order to gather transits to refine the parameters and publish the paper.
Some of us joined the campaign but the weather in France wasn't good and some couldn't observe or their observations weren't complete because of passing clouds.
All the necessary info was passed along by Alex in order to prepare well all details for the observation.
Started the preparations and luck was on my side this time making the weather clear and the wind droped to less than 10km/h.
This star has a neighbor very close and can't be resolved with my setup (0.84"/px). To do the photometry I had to use a phot large enough to include the flux of both stars.
In order to have a good SNR I chosed a CBB filter (Clear with BlueBlocking) also known as the exoplanet filter. The exposure set to 120s.
This is the resulting plot from the photometry, a perfect exoplanet signature.
From this plot we can refine the ephemeris and calculate the planet radius.
Using data from the spectroscopic observation we can determine the planet mass and using both data we get planet density.
