??????MPPC? ???????

1
??????MPPC????????

• ?? ? (KEK)
• KEK ?????? ?????G???

2
MPPC

• MPPC???????
• MPPC?RD???
• ???????????????
• ?????????????????????
• ?????

3
PPD (Pixelated Photon Detector)

• PPD ??????????APD???????
• MPPC ????????????
• ???Pixel???
• ?????e-h????Geiger??????(105106)??????????APD???
  ???Geiger????
• ????????????????? (binary device)
• ???????????1pixel?1???????
• Geiger???????pixel? ????? ?????
• ?????????????Wired-OR (????1??)
• ?????????? Geiger???????pixel? ???
• ???????????????(?????) lt ???????.
• ???????,?????(70V),?????
• ??????????, ?????????(??kHz),??????

????
????
1p.e.
2p.e.
pedestal
3p.e.
4p.e.
?
??(??)???????S/N?????????? ???????
4
MPPC?????????
gain
????
???
1p.e.

• ???
• ?????????V0
• ?????????????????
• Vo???????????. (50mV/K)
• ???????????V ? Vbias V0???
• ??????(PDE)
• PDE egeom? Q.E. ? egeiger
• egeom ???????????
• Q.E. ?????e-h??????
• egeiger e-h??Geiger????????
• ?????????
• ??????e-h?????1??????????
• ??????
• ????????????????????????????????
• 1???2????????????
• ???????
• ?????????????????????.
• ?????
• ????????

Vbias
pedestal
??????
V0
5
MPPC?RD???

• T2K????????????????
• 15,000ch (Mar. 2008) 1.3?1.3mm2
• ???????300?????????????????????????
• ILC??????????????????
• 1600pixel 5000?
• ??????????????????????????????????????ltlt????
  ????1?????????? ?????
• MPPC????????????
• ?????????? 4ns (1600pixel)
• ?????????? gtgt ??????
• Belle Aerogel-RICH??RD
• 3?3mm2?????
• ??????????????(??????)
• ?????
• ?, p, n, ????(C)
• ??(LN2)????

6
???????

• ?????(??_at_???)
• ??????? 0.81.5MeV
• Flux 1.5?109 n/cm2/Wh???????????????????
• ????
• 1??(5/17,18)
• 0.83.3?108 n/cm2
• 1011 n/cm2, 1012 n/cm2, 1013 n/cm2
• 2??(11/15,16)
• 3?108 n/cm2 3?1011 n/cm2

??
T. Nakamura, T. Nakadaira (KEK), K. Miyabayashi,
T.Hirai(Nara WU), T.Matsumura(NDA), S.Tsunoda
(TSU), H.Yamasaki, T.Ikuno(Tsukuba),T.Nakagawa,
I.Saito(U-tokyo)
7
?????????
1.6108 n/cm2?????????(100pixel)
1.001011 n/cm2 ?????????(100pixel)
100pixel 1.0?1010 n/cm2 ?? 400pixel 1.0?1011
n/cm2 ??
100pixel 3.0?1010 n/cm2 ?? 400pixel 1.0?1011
n/cm2 ??
??????????????????
??????????????????????.
??????????1010n/cm2(100pixel) 1011n/cm2(400pix
el)??????????.
????????????????????????????????.
8
??????

• ????10101011n/cm2???????????????????????1??????
  ?????????.? MPPC????????????????

400pixel, 31010 (n/m2),Vop,
11/24
11/15
9
???(I-V??)

• ???????????I-V????????.
• ????????????????
• ?????????????????????????

60Co g-ray PD07 T. Matsubara (TIT)
3x10 11 n/cm2
???70.92V,5uA
10
1011 n/cm2????????????
400pixel
100pixel
preliminary
preliminary

• ??????????????????????
• ?????????????????????????????????????(????????????
  ??????)

11
1011 n/cm2??????
400pixel
100pixel
preliminary
preliminary

• ?????????????????????????

12
??? vs. DV
preliminary
????????????????????????????? ???????????????????
?
13
??? vs. DV
400????????????1010 n/cm2??? ???????????
14
?????????

• MPPC??????????????????????????????????????????????
  ???
• ???????1011 n/cm2 ????????
• 1011 n/cm2?????????????????
• PDE????????????? ??????????????? ?????????