CMB??????: LiteBIRD

1
CMB?????? LiteBIRD
?????????????? ????, LiteBIRD collaborations ????
???????(????)
?????? ???? 9?10 -13?
2
LiteBIRD

• Lite (light) Satellite for the studies of B-mode
  polarization andInflation from cosmic background
  Radiation Detection
• ?? CMB?B-mode?????
• ????? ?????????????????????????????????
• ???????? ??????
• 2008?9?JAXA??????WG?????

?????? ???? 9?10 -13?
3
Collaboration

• ????,???? (ARD/JAXA)
• ????(Caltech)
• ????, ????,????,????(ISAS/JAXA)
• ????,????,????,????,???,????,????,?????,????,????
  (????)
• ??? (???)
• ????,?????,??? (?????)
• Julian Borrill (LBNL)
• ????,???? (????)
• ???? (???)
• ????,??? (????)

??????????????
?????? ???? 9?10 -13?
4
Science goals

• ???????????B-mode????? ( l ? 200 ) ???????
• Lensing???B-mode????? ( l ? 200 )
  ?????????????????B-mode?????????????
• ???????????????????
• 60-300GHz?????????(???????????????)???????????

????????
EE
Planck LiteBIRD
r 0.1
BB
?????? ???? 9?10 -13?
5
Science goals

• ???????????B-mode????? ( l ? 200 ) ???????
• Lensing???B-mode????? ( l ? 200 )
  ?????????????????B-mode?????????????
• ???????????????????
• 60-300GHz?????????(???????????????)???????????

????????
EE
EE
Planck LiteBIRD
r 0.01
BB
?????? ???? 9?10 -13?
6
Design requirements

• ??????CMB????????????????

• LiteBIRD??
• ???????????????????????
• ?? lt 400kg,
• ?? lt 1m
• ?????????????????????????
• ???? gt1000
• ?? 30cm
• ?? 3030
• ??????????????????????????????
• ?? 60?300GHz (5?1mm)
• ??????????????????????
• 1/2??????????????????? lt 30cm

???????1??????? (?????)
?????? ???? 9?10 -13?
7
Optics design

• Zemax???????????
• ??????????
• ?? 3030
• Strehl ratio gt 0.8 (????) ???????? _at_ 300GHz????
• ??? ?????????
• (??????????????????????????Si????????)
• ???????2K???
• 1/2???????????
• ???????
• ???????????
• ???????????????

IR blocker
Aperture ?? 30 cm 1/2???
HDPE ?????
75cm
HDPE ?????
??????????
??? ?? 30cm
?????? ???? 9?10 -13?
8
Beam characterization
From Shimon et al.
From EPIC report Bock et al.
?????????????????????????????? ??????????? ?
yes ?????? ???????????????? ??????
1/2?????????????????????
? BICEP?QUITE?EBEX?PolarBear
?????? ???? 9?10 -13?
9
Broadband coverage

• ???????
• 1/2????????
• ?????1/2??? (n?3??????) ?????????

1/2???
HDPE ???
1/2???????? 1/2???????7???????
HDPE ???
???
?????? ???? 9?10 -13?
10
Foreground and focal plane real estate

• ??????????????(N gt1000)???
• ?
• Multi-chroic?????????????????????????????????

From A. Lee (UC Berkeley)
Freq (GHz) Beam (arcmin) Ndet NET (mK?s) wp-0.5 (mK-arcmin)
90 60 400 38 3.5
150 36 600 34 3.2
300 18 200 110 10.1
total - 1200 - 2.3
Center 300GHz, 4.2 cm 1st ring 150GHz, 15cm 2nd
ring 90 GHz, 24cm
Center 300GHz, D4.2 cm 1st ring 90 150GHz,
D20cm
?????? ???? 9?10 -13?
11
Foreground and focal plane real estate

• ??????????????????????
• ????
• ??????
• ???????

CMB-pol, EPIC-LC??
Freq (GHz) Beam (arcmin) Ndet NET (mK?s) wp-0.5 (mK-arcmin)
30 155 8 80 87
40 116 54 71 29
60 77 128 60 16
90 52 512 52 7.0
135 34 512 49 6.6
200 23 576 54 6.9
300 16 576 92 12
total 2366 3.6
Inside 90, 135, 200, 300 GHz, D23cm Outside
30, 40, 60GHz, D31 cm
?????? ???? 9?10 -13?
12
???

• LiteBIRD????????????B-mod???????????
• ??????????????????????????????????????????????????
  ????????????
• ?????????
• ???????????????
• ???????? v.s. ????????????
• ?????????
• ????????? ? ??????????/???

?????
?????? ???? 9?10 -13?
13
Focal plane

• ????Al STJ?TES????????????????????

IR blocker
Aperture ?? 30 cm 1/2???
HDPE ?????
Development at UC Berkeley
75cm
HDPE ?????
??? ?? 30cm
??????????
??? ?? 30cm
?????? ???? 9?10 -13?