JHF n experiment (Requirements for Electronics)

1. KEK Electronics Wroskhop October 4-5, 2001 JHFn experiment(Requirements for Electronics) • Introduction to JHFn • Requirement to Front n detectors • Example-1: K2K Upgrade Electronics • Example-2: Super-K upgrade (FADC) • General Comments • Summary T. Nakaya (Kyoto Univ.)

2. JHF Neutrino Working Group ICRR/Tokyo-KEK-Kobe-Kyoto-Tohoku-TRIUMF Y. Itow, T. Kajita, K. Kaneyuki, M. Shiozawa, Y. Totsuka (ICRR/Tokyo) Y. Hayato, T. Ishida, T. Ishii, T. Kobayashi, T. Maruyama, K. Nakamura, Y. Obayashi, Y. Oyama, M. Sakuda, M. Yoshida (KEK) S. Aoki, T.Hara, A. Suzuki (Kobe) A. Ichikawa, T. Nakaya, K. Nishikawa (Kyoto) T. Hasegawa, K. Ishihara, A. Suzuki (Tohoku) A.Konaka (TRIUMF, CANADA) 15,5

3. 1. Introduction to JHFn (Phase-I) • Neutrino Oscillation (nmne ,nm, nt or ns) : P(nmnm)=1 - sin22qsin2(1.27 Dm2 L/E) -- suggested by SK atmospheric neutrino sin22q P(nm nm) Dm2 En (GeV)

4. JHFn (April, 2007 - ) ~1GeV n beam Kamioka JAERI (Tokaimura) Super-K: 50 kton Water Cherenkov 0.77 MW 50 GeV PS ( conventional n beam) • Precision measurement of n oscillation parameters by nmnm(sin22q23、Dm232). • Discovery of nmne(sin22q13) • Confirmation of nmntwith p0 in Neutral Current (NC). 3 generations

5. N 50GeV PS 3GeV PS Neutrino Beam Line 600MeV Linac FD1 To SK JHF facility and n beam JAERI@Tokai-mura (60km N.E. of KEK) Construction 2001～2006 (approved) 1021POT(130day)≡ “1 year” FD2 at 2km away

6. Principle & Goal Intense Narrow Band Beam (NBB) • Beam energy is tuned at the oscillation maximum. • High sensitivity • Less background • ~1 GeV beam for good n energy reconstruction. Sensitivity (Phase-I): d(sin22q23)< 1% sin22q13 < 0.6% (90% CL) dDm232< 5% ～3,000 n events/yr (Phase-II w/ Hyper-K): CP study (|d|<20°)

7. 2. Requirement to Front n detectors • Functions of Front n detectors (FD): • Normalize n flux to Super-K. • Measure n (nmand ne) spectrum at FD and estimate the spectrum at Super-K. • Study n interactions to estimate BG events to Quasi-Elastic (QE) interaction. Oscillation with sin22q=1 and Dm2=310-3eV2 No Oscillation non QE BG QE En (MeV) En (MeV)

8. A Front n detector: • massive (small n cross section: K2K ~1ev/kton) • fine segment or good vertex reconstruction • good timing (fast spill to reject cosmic ray and beam BG) k2k beam ~1msec 8.4m (scinti. signal) Background K2K-1kt Water Tank

9. JHF n detectors n beam FD2 Super-K 280m FD1 study of n interaction (~1,000n interactions/ton/day) 2km spectrum comparison 295km Network based DAQ for beam-line (at several stations), FD1 and FD2.

10. Front n detectors • Beam Structure: • 8 bunches in ~5.23msec spill (every 3.3 sec)  Depth of the memory ~10 msec. • Timing resolution << 10nsec. • Water Cherenkov detector(at FD2.) • One Volume of O(1kton) : (high rate) • same as Super-K: • Fine segmented detector (at either FD1 or FD2) • detect low energy particles. (~a few cm track) • many channels (104~105 channels) • Muon detector (at either FD1 or FD2) • large coverage to measure the profile. • many channels w/ TDC.

11. 3. Example-1: K2K Upgrade Electronics Summer, 2003- Full active and fine segmented scintillator (222cm3) w/ WLS fiber readout +MA-PMT (ADC,TDC) 20,480 channels m p

12. Electronics schematics 64ch MA-PMT 320 (=20,480ch) 32ch2 shaper, sample, hold, multiplexed and analogue readout chips w/ self triggering. 32ch2 VA/TA Slave/Master Controlers CPU ADC (640 inputs) CPU Network 32ch serial line 32ch OR TDC (640 inputs) CPU VME

13. 2 0 31 1 controller ADC ch0 ch1 ch2 ch31 VA TA 640 32OR TDC trigger (inside) • Shaper analogue signals (TA: ~10 nsec, VA:~500nsec) • Trigger by OR of all 32ch (generated by TA) • Hold the pulse high of 32 signals (VA) • Multiplexed, and readout signals clock by clock (VA).

14. Spectation * PE=Photo-Electrons

15. 4. Example of SK upgrade (FADC) • Super-K(~10,000ch) and K2K-1kt (680ch) use ATM modules. 2 parallel channels A-ch ADC/TDC Analogue signal switch to reduce a dead time (~300nsec dead time) B-ch ADC/TDC

16. FADC • 500MHz FADC for PMT sum is used at K2K 1kt Water Cherenkov detector. • To identify multiple interactions (~0.5events/spill), which do not happen at Super-K. • Super-K is also planned to install the newly developed 500MHz FADC (1000 channels for 10,000 PMTs). • The similar FADC will be used at the new Water Cherenkov detector at JHFn.

17. 5. General Comments • In JHFn experiment, we need inexpensive and compact electronics. • MA-PMT: < ¥2,500/chnote • We do not need a PIPE-LINE DAQ, but need a Buffer memory(spill is every 2~3 sec.). • FADC is one of good candidates, though it is still expensive to be used for all channels. • An Analogue ASIC such as VA/TA is desired to be used at the front-end of MA-PMT. • We may also need an inexpensive TDC system such as TMC for Muon chamber.

18. 6. Summary • JHFn experiment will start in 2007 at the same time when JHF accelerator complete. • Discovery of nmne. • Precision measurement on the n sector (~% level). • CP violation search in n oscillation w/ Hyper-K. • The new Narrow-Band n beam line, the first front detector at JAERI and the second front detector at 2km away from the target will be constructed.

19. FADC will be developed for the new Water Cherenkov detector. • Inexpensive multi-channel electronics will be developed for the fine grained detector. • Milestone • SK 500 MHz FADC (~1,000ch) 2002 • K2K upgrade electronics (~20,000ch) 2003 • JHFn2006 Definitely we need a support from KEK electronics group and cooperation.