1. Rocket experiment for Neutrino Decay Search Overview Yuji Takeuchi (Univ. of Tsukuba) Oct. 24, 2013 Neutrino Decay collaboration meeting 1

2. Collaboration Members (Japan-US collab.: Search for Neutrino Decay) As of Oct. 2013 Japan Group Shin-Hong Kim, Yuji Takeuchi, Kenji Kiuchi, Kanai, Kazuki Nagata, Kota Kasahara, Ryuuya Ichimura, Takuya Okudaira, Kouya Moriuchi, Ren Senzaki (University of Tsukuba), Hirokazu Ikeda, Shuji Matsuura, Takehiko Wada (JAXA/ISAS), Hirokazu Ishino, Atsuko Kibayashi, Yasuki Yuasa(Okayama University), Takuo Yoshida, Shota Komura, Ryuta Hirose(Fukui University), Satoshi Mima (RIKEN), Yukihiro Kato (Kinki University), Masashi Hazumi, Yasuo Arai (KEK) US Group Erik Ramberg, Mark Kozlovsky, Paul Rubinov, Dmitri Sergatskov, Jonghee Yoo (Fermilab) Korea Group Soo-Bong Kim (Seoul National University) 2

3. 3

4. Motivation LRS: SU(2) L ｘSU(2) R ｘU(1) B-L 4 SM: SU(2) L ｘ U(1) Y 10 26 enhancement to SM PRL 38,(1977)1252, PRD 17(1978)1395

5. Photon Energy in Neutrino Decay m 3 =50meV m 1 =1meV m 2 =8.7meV E  =4.4meV E  =24meV Sharp Edge with 1.9K smearing Red Shift effect dN/dE(A.U.) 5

6. 6 Zodiacal LightZodiacal Emission Galactic dust emission Wavelength[  m] Integrated flux from galaxy counts Galaxy evolution model CIB measurements(  AKARI,  COBE) Astrophys. J. 737 (2011) 2 Sharp edge with 1.9K smearing and energy resolution of a detector(0%-5%) Red shift effect CIB (fit from COBE data) C B decay 6.7  away from flat

7. Neutrino lifetime lower limit from AKARI data x10 12 yr Published in Jan. 2012 AKARI CIB data after subtracting foregrounds

8. Detector requirements 8

9. 9 Zodiacal LightZodiacal Emission Galactic dust emission Wavelength[  m] Integrated flux from galaxy counts Galaxy evolution model CIB measurements(  AKARI,  COBE) Astrophys. J. 737 (2011) 2

10. FIR photon spectroscopy with diffraction grating + Nb/Al-STJ array Nb/Al-STJ array 10

11. 赤外線観測ロケットによる宇宙背景ニュートリノ崩 壊探索 LHe 減圧 1.6K 分光・光学系 DAQ 3 He 減圧 <0.9K 11

12. Backup 12

13. Energy/Wavelength/Frequency 13

14. Feasibility of FIR single photon detection 14

15. Feasibility of VIS/NIR single photon detection 15

16. CIB Experiment for Neutrino Decay Search with JAXA Rocket Rate Calculation and Expected Lifetime Limit 黄道光（前景放射） 系外銀 河 第一世代の星 ? 背景放射 CMB DG L FIR-rocket λ ＝ 40 ～ 80μm