1. Collaboration meeting HES-HKS 2008/11/24 T.Gogami

2. ＨＴＯＦ１Ｙ There are gaps between scintillators. About  3mm (from measurement) How much event loss?  Geant estimation

3. Geant results No gap  ~1% 3mm gap  ~7% *Loss means comparison hits of HTOF1Y with hits of KDC12.

4. Stagger plan To reduce event loss from gaps  Let’s stagger scintillators! particles Former HTOF1Y(Top view)

5. Geant simulation 5[mm] overlap is enough to reduce event loss. About  loss 1.1% D=66-71

6. HTOF1Y Light-Guide Basically frame & magnetic shield will not change. Redesigned Light-guide.  already ordered(We’ll receive it in two weeks.) Next Plan -How to make good position? -How not to bend scntillators?  spacer, shelves ?

7. Summary ///HTOF1Y/// ・ Gap loss study no gap  1% 3mm gap  7% ・ Stagger plan Redesigned Light-guide  already ordered problems  how to make good position. how not to bend scintillators.

8. End