First Year of BABAR/PEP-II - Harvard University Laboratory for ...

(ρ, η) → (sin2α, sin2β) plane.
Today’s UT — Angles
◆ –0.95 < sin2α < 0.50 (95% C.L.)
◆ 0.50 < sin2β < 0.85 (95% C.L.)
We know very little about sin2α.
→ We need a measurement.
We know sin2β rather well.
◆ This is assuming the SM.
→ Direct measurement can either
➤Confirm the SM.
➤Indicate New Physics beyond the SM.
-1
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
CP violation in the B system allows us (BABAR and the
competitors) to measure these angles.
sin(2β)
1
sin2β
1
0.8
0.6
0.4
0.2
0
-0.2
-0.4
-0.6
-0.8
-1
-1
0
sin(2α)
sin2α 1
First Year of BaBar/PEP-II Masahiro Morii SLAC