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J-PARC Upgrade Plan for Future and Beyond T2K T.Ishida Neutrino Experimental Facility Group J-PARC / KEK [CONTENTS]. Introduction Status of Accelerator Operation * J-PARC Upgrade Plan * Summary . * By courtesy of T. Koseki (J-PARC) . 1. Introduction.
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J-PARC Upgrade Plan forFuture and Beyond T2KT.IshidaNeutrino Experimental Facility Group J-PARC / KEK[CONTENTS] • Introduction • Status of Accelerator Operation* • J-PARC Upgrade Plan* • Summary * By courtesy of T. Koseki (J-PARC)
T2K: The 1st experiment with J-PARC n facility • Discovery of nm ne oscillation (ne appearance) • Precision measurement of nm disappearance • Open possibility to explore CPV in lepton sector
T2K ne Appearance Result[data until Jun.2012] • 11 candidate events are observed with 3.01x1020pot • Nexp=3.22±0.43(sin22q13=0) 10.71±1.10 ( =0.1) • Probability=0.08%(3.2s) The 1stne event after EQ (Mar.2012) Evidence of ne appearance
Next Step of T2K Near Detector Observation • Systematic error reaches already as small as 10% owing to near detector. • We can achieve 5s significance with ~8x1020 pot. It is within our reach before shutdown in summer, 2013. (MeV)
Future LBL plans using J-PARC J-PARC+HK @ Kamioka Fid. Mass 560kt, L=295km OA=2.5deg LoI: The Hyper-KamiokandeExperiment Submitted Sep.2011 [arXiv:1109.3262v1], J-PARC+LAr @ Okinoshima 100kt, L=658km OA=0.78deg • Current: T2KJ-PARC ~0.75MW+ 50kt WC @ 295km 2.5° J-PARC P32 (LAr TPC R&D), arXiv:0804.2111
nm→neprobability 295km Normal hierarchy Required Run-Time To discover CPV: 10 years x 750kW • WC: 3yr x 750kW (n) + 7yr (nbar) • LiqAr: 10yr x 750kW (n) Neutrino Anti-neutrino 658km Second max. 0.4GeV First max. 1.2-1.4GeV
Expected neCC candidates (HK LOI) 0.75MW×3yrs 0.75MW×7yrs sin22θ13=0.1 • To go to CPV discovery, intensity upgrade of J-PARC is the key ~4,000 signal ~2,000 signal δ=0 δ=1/2π δ=π δ=3/2π δ=0 δ=1/2π δ=π δ=3/2π νe candidates stat. error only stat. error only diff. from δ=0 case δ=1/2π δ=π δ=3/2π δ=1/2π δ=π δ=3/2π
January 2008 Hadron Experimental Hall J-PARCJapan Proton Accelerator Research ComplexJoint project btw. KEK & JAEA Main Ring A round = 1,568m Materials and Life Science Facility(MLF) Near Neutrino Detectors • FY01~08 Construction • Nov. 2006~LINAC • Oct. 2007~RCS • May 2008~MLF/MR • Dec. 2008~ MR@30GeV • Jan. 2009Hadron • Apr. 2009Neutrino Neutrino Target Station 3NBT Neutrino Beam 3-50BT 3GeV RCS A round=348m Transmutation Experimental Facility LINAC (330m)
Beam delivery from RCS to MLF Stable operation of 275 kW successfully demonstrated Beam power [kW] Availability [%] Accumulated beam power [MWh] • Design Intensity:1MW Accumulated beam power (New target) [MWh] Accumulated Beam Power [MWh] Beam Power [kW] Availability [%]
Delivered POT to Neutrino Facility(MR Fast Extraction) 3.01x1020pot Jun.9’12 1x1014ppp • After earthquake, beam operation resumed in the same year, and physics run resumed within one year. • Stable operation at ~190kW achieved, 1x1014ppp (1.26x1013x8b) is the world record of extracted protons per pulse for synchrotrons. 8 bunches 2.92 2.56s ~190kW 6 bunches Rep=3.52s 50kW 8 bunches 3.2s 145kW 1.43x1020pot until Mar.11,’11 Physics Run resumed on Mar.8, 2012 Protons Per Pulse Delivered # of Protons Beam resumed on Dec.24,2011 [w/o horn operation] Dec.24,25, 2011 Jan 20-25, 2012 Run-1 Run-2 Run-3
High power operation in FX mode ( March 5 to June 9, 2012) • Delivered beam power is limited by beam loss at the injection / collimator section. • Ring collimator upgrade was being taken place during 2012 summer shutdown. The capacity is now enlarged to 2kW. MR Power [kW] 200kW 100kW 450W Capacity of Collimator 1ms average 10 µs average 1000W Beam loss [W] 600W 400W Jun.9 Mar.5
LINAC Upgrade Repetition: 25Hz, Pulse width: 0.5ms • New accelerating structure, ACS, will be installed to increase the extracted beam energy from 181MeV to 400MeV • Front-end part (IS+RFQ) will be replaced to increase peak current from 30mA to 50m • These installations are scheduled in2013 shutdown 30mA 50mA 400MeV RF antenna colab.w SNS 181MeV ACS, Annular Coupled Structure linac
Power upgradefor Linac & RCS Original power upgrade plan of RCS to MLF Power [MW] Revised plan 2008 2009 20102011201220132014 2015 JFY Installation, Beam test Fabrication, Offline test R&D, Fabrication, Offline test R&D, Fabrication, Offline test User operation, Power increase Budget for the Linac and the RCS upgrade is mostly secured. We revise the power-up curve after the earthquake: shifted 6 months.
For Higher Beam Power in MR Fast Extraction • Number of particles in one pulse is limited by the beam loss due to the space charge effect • ~450kW is estimated upper limit with current apparatus • To achieve higher beam power : • Higher beam energy than 30 GeV (Original plan) • Higher repetition rate than 0.4 Hz 1.00 Tracking simulation of the MR fast extraction with space charge effect Np=2.2 x 1014ppp Beam power: 435 kW at 30 GeV / 0.4 Hz Beam loss ~ 1.3 kW 0.99 Survival ratio 0.98 Acceleration Injection 0.97 0.96 0 0.1 0.2 0.3 Time (s)
Magnet Saturation in the 50 GeV operation Ratio of B-field for dipole magnets • The saturation effect deteriorates the field quality of the main magnets • Total magnet power consumption for 50GeV operation is x4 times larger than that for 30GeV. • Considering the situation after the earthquake, the high electric cost is fataldisadvantage for the higher beam energy option. 1.01 ~30GeV 1.00 40GeV 0.99 0.98 50GeV 50GeV 0.97 0.96 Y(mm) Ratio of total magnet power consumption 50GeV P50GeV= 2P40GeV=4P30GeV 40GeV 30GeV
T=2.5cm 60kg For 1 Hz Operation 80cm FX/RF section PS Building #3 (3) Upgrade of injection and extraction devices (2) Replacement of the rf cavities New magnetic core material, which has x2 times higher impedance than present one, is developed. New PS Building SX section (4) Upgrade of ring collimator section2kW3.5kW Condenser bank For energy recovery Injection/collimator section PS Building #2 PS Building #1 Replacement of the magnet power supplies All the main magnet power supplies will be replaced with newly developed high rep./low ripple PS. A new PS building to be constructed.
The Medium-Term Plan of the MR-FX until 2017 • We adopt the high repetition rate scheme to achieve the design beam intensity, 750 kW. • Rep. rate will be increased from ~ 0.4 Hz to ~1 Hz by replacing magnet PS’s and RF cavities • A new budget is needed for replacing MR main magnets. Manufacture installation/test R&D Manufacture installation/test R&D Kicker PS improvement、Septum 2 manufacture /test LF septum, PS for HF septa manufacture /test
Project Review by MEXT • On March~May 2012, progress of the J-PARC project in the recent 5 years was evaluated by a review committee at Monka-Syo, the Ministry of Education, Culture, Sports, Science & Technology in Japan (MEXT). • An evaluation report was issued. • The 5-year medium term plan (2013~2017) was endorsed by the review committee. • For MR, scenarios for Multi-MW output beam power for neutrino experiment, are being discussed • One of feasible schemes: Introduce 8 GeVemittance damping ring betw. RCS and MR • The detailed scheme for the future MW proton driver is to be discussed in the next five years, to submit budget proposal to the government in 2018 or later.
Doubled Rep.rate: Impact to Neutrino Facility ? • Thermal shock will be reduced for equipments which are exposed to beam directly (Target, beam window, profile monitor, beam dump…) • Cf. T2K Target: ΔT = 200K/spill @ 750kW, Safety factor = ~3.5 for original design • For doubled rep.rate option, ΔT = 100K/spill, Safety Factor= ~7 (?) • T.Nakadaira’s talk. • Heat load for equipments will stay same. • Cf. T2K Target: ~60kJ/spill @ 750kW • Fatigue of horns will become more severe. • Update of power supplies • Reconfiguration of bus-bar & strip line layout • T.Sekiguchi’s talk
4. Summary • T2K achieved 3.2 s significance for nmne appearance signal using 3x1020POT. • 11 candidate events. Need more statistics. • We can achieve 5s significance with ~8x1020 pot. It is within our reach before shutdown in summer, 2013. • To going to precision q13 measurements and further CPV discovery, upgrade of J-PARC acc. is quite essential. • Upgrade of J-PARC accelerators • To increase #p/bunch • Increase MR collimator capability (2012 Summer; done) • Upto 450W 2KW loss • LINAC frontend upgrade (2013 Summer) • Ion source, RFQ : 30mA 50mA • LINAC energy upgrade to 400MeV (2013 summer) • To realize MR 750kW operation, doubled rep.rate option is chosen. • Need to replace all magnet power supplies in ~5yrs • Need higher gradient RF core. • The mid-term plan is endorsed by the committee at MEXT.
5% systematics on signal, νμ BG, νe BG, ν/ν Expected Contours 7.5MW・years Normal mass hierarchy (known) True points Reactor q13 exps.(1σ) • Good sensitivity for CPV
CPV Discovery Sensitivity (w/ Mass Hierarchy known) 7.5MWyear sin22θ13=0.1 normal MH 2% all syst 5% all syst σ 74% region of δ covered at 3σ w/ 5% sys. error 10% all syst true δ (π) High Sensitivity to CPV w/ <~5% sys. error 26
On going R&Ds (1) - Power supply for main magnets- • High rep rate (~1 Hz): Energy recovery using condenser bank • Small current deviation: Current feedback, voltage feed-forward, NPC chopper.. - A small scale prototype model is manufactured and testing in 2011/2012. - A real scale prototype for one of the quadrupolefamilies will be manufactured and tested in 2012 and 2013. - Technical review committee meeting for the power supply R&D will be held in October 2nd , 2012.
On going R&Ds (2) - MA (Magnetic Alloy) loaded rf cavity with higher shunt impedance - A type of MA cores, FT3L (made by Hitachi metals), which is processed by annealing with magnetic field, shows higher impedance than FT3M, the present core used in J-PARC synchrotrons. We have manufactured the real size core of FT3L for the rf cavity of the MR in the J-PARC site in collaboration with Hitachi metals. The first manufactured real size FT3L core FT3L: annealing w/ magnetic field µQf FT3M: annealing w/o magnetic field Diameter 80 cm, thickness 2.5 cm, weight 60 kg. Frequency [MHz] The FT3L core has the impedance approximately twice of the FT3M. Six FT3L cores are used at one gap of the cavity tank in the #9 cavity, which is installed in the 2012 summer shutdown.
Injection energy and beam loss in the MR Simulation of beam survival in the injection period of the MR for the RCS 1MWeq. beam (4e13 ppb) 6.0 GeV 1.0 3.6 GeV 3.4 GeV 0.98 3.2 GeVInj: Ave Inj loss 1.5% (1.2 kW Inj loss for MR 750 kW ) Survival ratio 0.96 3.0 GeVInj: Ave Inj loss 3.2% (2.4 kW Inj loss for MR 750 kW) 0.94 0 0.04 0.08 0.12 Time [s] Beam survival ratio is drastically increased by higher beam momentum.
Design of the 8-GeV BR : Lattice & parameters RF CAVs Parameters of the RCS and 8 GeV BR 8-GeV BR RF CAVs INJ+COLL EXT Beta & Dispersion for 1-superperiod H & V bx,y(m) hx,y(m) s (m)