The cosmology at 21 cm and BAO Radio

par Ana-Sofia Torrento (LAL)

mardi 26 févr. 2013, 11:00 → 12:00 Europe/Paris

Salle 101 (LAL)

Using the 21 cm line of neutral hydrogen will open a new window to observe the Universe at high redshifts. In particular, it will provide a complementary measurement to optical surveys to constrain the dark energy equation of state through the observation of the baryon acoustic oscillation feature (BAO) as a function of redshift. The intensity mapping is a technique which measures the total 21 cm emission without resolving individual sources. The BAO Radio project aims at using this technique to provide a 3-D cartography of the sky at 21 cm and detect the BAO feature up to z ~ 2 - 3. In this seminar I will present the results of an observation campaign towards nearby galaxy clusters carried out at Nançay Radio Telescope (NRT), which provided the validation of the BAO Radio hardware and analysis pipeline. I will also present the preparation of the next observation campaign at NRT, to investigate the feasibility of cross-correlating the 21 cm signal to large scale structrures observed by optical surveys, and therefore provide an estimation of the hydrogen fraction.

Poster SemAST.pdf