Machine learning day at SAp

On January, 22, 2016, we organized a day on machine learning in astrophysics at SAp, CEA Saclay. The pdf files of all talks can be found below. There were around 35 attendants (10 female, 25 male).


All talks are taking place at SAp, Salle Cassini (ground floor, on the left of the main entrance).

13:15 – 13:30h. Welcome, coffee.
13:30 – 14:30h. Balazs Kegl (LAL, CNRS), Introduction on (deep) learning
14:30 – 15:00h. Farhang Habibi (LAL), Star-galaxy classification in SDSS DR12
15:00 – 15:30h. Markus Rau (University Observatory Munich): Machine Learning for photometric redshift estimation
15:30 – 16:00h. Coffee break
16:00 – 16:30h. Malte Tewes (University Bonn), Weak-lensing shape measurement
16:30 – 17:00h. Marc Huertas-Company (Observatoire Meudon), Galaxy classification and morphology with ML
17:00 – 17:30h. Jean-Luc Starck (CEA Saclay), Learning and Blind Source Separation

Local information

CEA Saclay is around 23 km South of Paris. The astrophysics division (SAp) is located at the CEA site at Orme des Merisiers, which is around 1 km South of the main CEA campus.


See this page for hotels near Saclay. It is advisable to get accommodation along the RER B line (e.g. Gif-sur-Yvette, Orsay, Massy), or in Paris on the South bank (most convenient is 14th arrondissement).

Getting to SAp

By public transport

You can reach the SAp by subway train (RER) and bus, from Paris downtown (45 min travel time) and the airports Charles-de-Gaulle (1h30) and Orly (1h). Check this page for directions and time-tables.
Take the RER B towards Saint Rémy les Chevreuses or Orsay Ville until the stop Le Guichet. (Note that not all trains stop at Le Guichet, as indicated by the lights on the panel at every station.) From Le Guichet, there are public buses and CEA coaches to take you to Orme des Merisiers.


The coaches leave every 15 minutes between 8h and 9:45h. To reach the bus stop, exit the RER station at exit #2, rue de Versailles. Pass by the café La Terasse, cross the road towards the day-care and go down a little path (there are signs “Gare routière”) until you reach another road. The CEA coaches leave 50 meters up the road on the same side (follow the other people). The ride is about 10 minutes, Orme des Merisiers is the first bus stop.







After 9:45am you will Orme_maphave to take public transport. The public bus stand is on the opposite side of the road from where the coach leaves. The line 9 goes every 10-20 minutes, and takes about 20 minutes to reach Orme.

After you exit the bus at the stop Orme des Merisiers, cross the road, enter the campus by the road, go straight through the roundabout, and take the second road to your left after ~ 50m. The SAp is the reddish building is across parking lot, building number 709 (see map).




  1. Getting to Paris

By plane

Paris has two airports, Orly [ORY] and Charles-de-Gaulle [CDG]. From both airports, you can easily reach Saclay by public transport. From Orly it’s about 1h, from CDG 1:30h.

By train

By train you will most likely arrive at one of the train stations in Paris downtown. From there you can take the metro to get to the RER B which takes you towards Saclay. Go to to find how to reach the nearest RER B station.