Mon, Feb 27, 2012, 4:00 pm to 5:00 pm
ABSTRACT: Precise measurements of cosmic microwave background (CMB) polarization, especially its odd-parity patterns (B-modes) at large angular scale, prove a scenario of inflationary universe. Many experiments are aiming to detect them. High Energy Accelerator Research Organization (KEK) have joined the race for the B-modes search from 2007; we have started our activity with joining to the QUIET collaboration. Our target is measurements of the B-modes "spectrum", especially both ionization bump and the first peak. Satellite mission and the ground based experiments toward it allow such measurements. I will introduce the strategies and activities in KEK and related collaboration activities towards our target.