KEK/J-PARC-PAC 2018-27
Aug. 9, 2018
J-PARC Program Advisory Committee
for the Nuclear and Particle Physics Experiments
at the J-PARC Main Ring
Minutes of the 26th meeting held
18(Wed.)-20(Fri.) July 2018

OPEN SESSION:
1. Welcome and Mandate to the Committee:

K. Tokushuku (KEK)

2. J-PARC Center Report:

N. Saito (J-PARC/KEK)

3. J-PARC Accelerator Status & Plan:

F. Naito (J-PARC/KEK)

4. Report from the Neutrino Beam Line Review Panel K. Tanaka (J-PARC/KEK)
5. T2K(E11) /T2K-II (E65) Status and Plan 1― Overview, Analysis Status, and Plan ―K. Mahn (Michigan State)

6. T2K (E11)/T2K-II (E65) Status and Plan 2― Status Report and Beam Request ―T. Nakadaira (J-PARC/KEK)

7. E34(g-2/EDM):

T. Mibe (J-PARC/KEK)

8. E61(NuPRISM/TITUS):

M. Hartz (IPMU)

9. E56 (Sterile Neutrino Search):

T. Maruyama (J-PARC/KEK)

10. E14 (KOTO):

T. Yamanaka (Osaka)

11. E40 (Measurement of the Cross Sections of Sp Scattering):
K. Miwa (Tohoku)
12. P73 ( and Mesonic Weak Decay Lifetime Measurement with 3,4He(K-,p0)
Reaction):Y. Ma (RIKEN)
13. FIFC Report:

S. Uno (KEK)

14. E69 (WAGASHI/BabyMIND):

A. Minamino (Yokohama)

15. E71 (NINJA):

T. Fukuda (Nagoya)

16. E21(COMET):

Y. Kuno (Osaka)

17. Hadron Hall & SX Beam Status, Schedule and Target R&D Plan:

H. Takahashi (J-PARC/KEK)
18. E45 (Baryonic spectroscopy with 3-Body Hadronic Reaction) :K. Hicks (Ohio)
19. E36 (Lepton Universality):

S. Shimizu (Osaka)

20. E03 (Measurement of X-ray from X- Atom):K. Tanida (JAEA)

21. E07 (Double Strangeness):

J. Yoshida (JAEA)

22. E16 (Spectral Change of Vector Mesons in Nuclei):
S. Yokkaichi (RIKEN)
23. E62 (Precision Spectroscopy of Kaonic Atom X-rays with TES):
S. Okada (RIKEN)
24. E57 (Strong Interaction Induced Shift and Width of Kaonic Deuterium):
J. Zmeskal (SMI-OeAW)
25. Beam Time Schedule in 2016-2018

T. Kobayashi (J-PARC/KEK)

CLOSED SESSION:
Present: N. Aoi (Osaka/RCNP), M. Blanke (KIT), S. I. Eidelman (BINP),
J. Haba (KEK), K. Hanagaki (KEK/Osaka), D. Harris (FNAL, via network),
Y. Itow (Nagoya), F. Le Diberder (CNS/IP2N3/LAL),
A. Ohnishi (Kyoto/YITP), S. Kettell (BNL), R. Kitano (KEK),
M. Kuze (Tokyo Inst. of Tech.), J. Pochodzalla (Mainz),
W. Weise (TU Munich), H. Tamura (Tohoku), A. W. Thomas (Adelaide),
R. Yoshida (Chair, JLab), W.A. Zajc (Columbia),
K. Tokushuku (KEK-IPNS Director),
T. Kobayashi (KEK-IPNS Deputy Director) and N. Saito (J-PARC Director)

1. PROCEDURAL REPORTThe minutes of the 25th J-PARC-PAC meeting (KEK/J-PARC-PAC 2018-14) wereapproved.

2. LABORATORY REPORT
2-1 Welcome and Mandate to the Committee (Katsuo TOKUSHUKU, KEK IPNS
director)
The director of the Institute of Particle and Nuclear Studies (IPNS), Katsuo Tokushuku,
welcomed the PAC members. Tokushuku reported on the renewal of the committee

membership and assigned Rik Yoshida as the new chairperson of the Program Advisory
Committee for the Nuclear and Particle Physics Experiments at the J-PARC Main Ring(MR).
As an introduction of KEK-IPNS, he reported selected topics from recent activities, inparticular, the success of the first electron-positron collision recorded by the Belle IIdetector during SuperKEKB commissioning in April 2018. He described the J-PARC
history along with the beam power development of the MR. In the spring 2018, themachine recorded the highest power of 504 kW during a short test period at the fast
extraction (FX) and was operated stably at 51 kW for experiments in the Hadron Hall inthe slow extraction (SX) mode.
Tokushuku explained the progress of the experiments in the Hadron Hall in 2017-2018;
an experiment searching for double-Lambda hyper-nucleus using nuclear emulsion
plates (E07) was completed in 2017 at the K1.8 beam line, followed by a hyperonproton scattering experiment (E40). At the K1.8BR beam line, a study of hyperon
resonance (E31) has been completed. Then two Kaonic atom X-ray measurements(E62/E57) were in the beam line. E62 completed successfully in June 2018. At the KL
beam line, KOTO(E14) continues physics data acquisition and plans a detector upgrade
for further improvements of the background rejection. A construction of new beamlines
to provide the primary proton beam for E16 and 8-GeV primary proton beam for
COMET is in progress.
Tokushuku reminded the committee members of the general mandates and the approval
process of proposals. Then he presented a summary of on-going experiments andproposals. He reported that one new proposal and one LOI have been submitted to thisPAC meeting and showed a list of TDR’s for stage-2 approval requests submitted from
E45, E56, E34, E69, and E71 experiments.
The KEK long-term plan was also explained; KEK has settled on a Project
Implementation Plan (PIP) in 2016, stating that the highest priority are on the stable
operation with sufficient running time of the three major on-going projects (J-PARC,
SuperKEKB, and Photon Factory). As for J-PARC, the following upgrades are to becovered by the current yearly budget; construction of COMET Phase-I, reinforcement of
the facilities for T2K, neutron polarization project at MLF, construction of the central
portion of the MLF muon H-line, and completion of the high-momentum beam line in
the Hadron Hall. PIP also states that the KEK “future” projects that require extra
funding resource have the following priority; 1) upgrade of J-PARC MR for the HyperK project, 2) Particle Physics Program in HL-LHC/ATLAS, 3) construction of MLF
muon beam H-line and g-2/EDM experiment, 4) extension of the J-PARC Hadron
Experimental Facility.
For the stable operation of the J-PARC with improved performance, the short term
priority is on the upgrade of the MR power supply and a new Hadron Hall primarytarget for receiving beam power larger than 80 kW. Tokushuku explained the Mid-termplan of MR update settled in March 2018 with a conservative funding scenario.

Tokushuku summarized his presentation by showing a guideline for PAC discussion as
follows;•

No MR beam before Feb. 2019 since two major experiments (T2K, KOTO) are notable to take data in this period.

•

From April to June 2019, full operation (either SX and FX mode) is assumed to bepossible although it depends on the FY2019 budget.

•

After 2019 summer, no beam is available for SX before Jan. 2020 due to theprimary target replacement.

He requested the PAC to discuss the beam time schedule until summer 2019 based on
this condition.

2-2 J-PARC Center Report (Naohito SAITO, J-PARC Center Director)
The J-PARC Director, Naohito Saito, welcomed the PAC members. He explained theoperation status and beam power history of two accelerators, RCS and MR. Stable user
operations at a beam power of 490 kW, 51 kW, and 525 kW were successfully achieved
at Neutrino Facility, Hadron Experimental Facility, and MLF, respectively. He alsomentioned the successful one-hour test of 1 MW stable operation conducted at MLF.
Development status of MLF neutron and muon targets for 1-MW operation was
mentioned. Operation of the MLF at 1-MW beam power is critical for the Sterile
Neutrino Search JSNS2 (E56) and Muon g-2/EDM (E34) to achieve their target
sensitivities within their scheduled time line.
Saito mentioned the MR plan beyond 1-MW operation anticipated after magnet power
supply and relevant upgrades, for which J-PARC has formed a consensus with IPNS,
IMSS, and Accelerator Laboratory directors to invest the necessary resources bymanaging the available budget. Details of the J-PARC action plan in FY2018 wereshown; safe and stable operation of the facilities should be maintained while increasing
the beam power, continuing preparations for future projects and increasing scientificoutputs.
Before closing his presentation, Saito explained the MEXT Review, which assessed the
J-PARC project in June 2018 after six years since the last review, as well as the new
exercise of Japan Science Council (JSC) Master Plan likely to start. In 2017, JSC
selected 28 proposals as important projects, among which (1) Elucidation of the originof matter with an upgrade of the J-PARC experimental facility (2) Nucleon Decay and
Neutrino Oscillation Experiment with a Large Advanced Detector (Hyper-Kamiokande)
are included.

2-3 J-PARC Accelerator Status (Fujio Naito, J-PARC/KEK)Fujio Naito summarized the J-PARC accelerator status and plan. First, he explained that
there are two operational modes in Main Ring (MR); fast extraction mode (FX) for
neutrino experiments and slow extraction mode (SX) for hadron hall experiments. He
presented the operation summary since the last PAC held in January 2018. The SX
operation was performed in January, February and June while the FX operation was
performed from March to the end of May. Stable operation of the MR in SX mode has
been established with a beam power of 51kW. As for the MR FX mode, stable operation
with a beam power of 485kW as well as continuous 50 shots with 500kW has been
established successfully. It should be noted that double-bunch operation with a beam
power of 500 kW has been achieved at the RCS to provide proton beam to the MLF.
Moreover, 1 hour continuous operation of 1 MW beam to MLF has been successfully
carried out on July 3rd. Beam availability of 88.8% has been achieved during the FX
operation in FY2017 while the availability during the SX operation was only 65.9% due
to problems with SX-ESS (Electro Static Septum) reported in last PAC meeting. The
beam availability for the FX and SX operations from April to July 2018 was 86% and88.2%, respectively. He presented that down time during the FX mode was mainly
caused by MR RF failures and oil leakage at the heat exchanger of the transformer usedin the FX septum power supply.
Naito showed the status and results of accelerator studies. Intensive studies were carriedout in order to increase the beam power and to further improve the beam stability.
Accelerator group identified that beam loss in RCS and 3-50BT was caused by theenergy fluctuation of 400MeV beam from the LINAC. They introduced a new scheme
to compensate the beam energy using the debuncher-2 in L3BT, and confirmed that it
works well to keep Δp/p less than 0.02% and reduces the beam loss. Working towardhigher power operation, the 60 mA beam was successfully accelerated up to 400MeV in
the LINAC for the first time on July 4th. RCS studies were carried out for 1MW beam
operation. High intensity beam study for MR FX mode was also performed. The beam
power of 520kW was achieved in a single shot mode with the beam repetition cycle of
2.48 seconds. This indicates that the beam power can be as large as 1.1MW if the cycle
time is reduced to 1.16 seconds while the beam loss would be 1.5kW. Further beam
study is necessary to reduce the beam losses to establish the continuous higher beam
power operation. The MR group also found that there were longitudinal oscillation andthat the RF anode current reached the limit of the power supplies for the 500kW
operation. It is an issue to be solved for the stable operation above 500kW power. At the
moment they are developing an RF feedback system to damp the longitudinaloscillation. As for the SX mode operation MR study was performed to improve the duty
factor by further tuning the transverse RF frequency pattern, resulting in the duty factor
improvement from 42.6% to 50.9%. Higher beam power of 62.8kW in the SX mode
was also demonstrated. Beam study for MR 8 GeV acceleration and slow extraction
toward the COMET experiment was also performed successfully. Further studies willcontinue in order to understand the proton leakage observed in the K4 rear bunch
position in the 1st 100 milliseconds during beam extraction.
Naito reported the status of MR power-supply upgrade. Construction of three dedicatedbuildings for new power supplies has been completed. New power supplies andcapacitor banks for them are already installed in some of the buildings. Commissioning

of new power supply is in progress. He showed the mid-term plan of the MR. The
repetition cycle of MR operation will be shortened from 2.48 seconds to 1.32 seconds
for the FX mode after completing installation of the new power supplies in 2021.
Naito concluded his presentation by showing a tentative operation schedule of the MR
in the first half of FY2019 (January to July) with accelerator study plans for both FX
and SY modes.

2-4 Report from the Neutrino Beam Line Review Panel (Kazuhiro Tanaka, JPARC/KEK)
Kazuhiro Tanaka reported the outcome from the Neutrino Beam Line Review Panel.
Details are described in the review report [KEK/J-PARC-PAC 2018-26]. Further
comments are in Sec 3.

2-5 FIFC Report (Shoji UNO, IPNS, KEK)
Shoji Uno presented a report from the Facilities Impact and Finance Committee (FIFC).
He reported on the meeting held on June 27th, 2018 at Tsukuba campus. FIFC
discussed the feasibility of E45, E69 and E71 where all of the experiments arerequesting stage-2 approval based on TDR. New reviewer, Yasuhiro Sugimoto(KEK),
jointed from this meeting instead of Junji Haba(KEK). Rik Yoshida (J-Lab.), the newchairperson of J-PARC PAC, was invited as an observer.
Uno first explained the review results of E45 experiment. The purpose of the E45
experiment is to measure the decay of N* resonances through the πNàππN reactions at
the K1.8 beam line. The E45 experiment had been reviewed in the previous FIFC
meeting. In the June meeting, the experimental group reported on all of the issues which
are described in the previous report, and those responses satisfied the committee, on thewhole. Uno showed some of examples of the responses from the experimental group.
The first example is the design of the installation tool of the liquid H2 target into the
TPC, which was a missing item of the previous TDR. The design and the detailed
procedure for the installation shown by the experimental group are satisfactory. The
second example is the design of the segmented TPC hodoscope in the forward region asrecommended previously. The better quench protection system in the superconducting
magnet was also conducted as recommended. Uno explained that one remaining issueof E45 was the results of the beam test, which is expected to be presented in this PAC
meeting.
Uno discussed the review results of E69(WAGASCI/Baby-MIND) experiment next.
The purpose of the E69 is to measure the differential cross section of the neutrino andanti-neutrino interaction with nuclei in a water target at around 1GeV neutrino energy.
Uno explained that the fine-grained detectors with/without water (WAGASCI detector)
have been extensively tested since 2016 as a test experiment, T69. The Baby MIND

muon detector has been tested with beam at CERN in 2017, and it was already installedin Feb. 2018 and tested in the NM hall. Functionality of those detectors has been
examined and verified. FIFC concluded that there was no serious technical issue
remaining. E69 group has also merged with the T2K collaboration already and FIFC
expects communication and coordination will become easier. FIFC expects that theachievability of the physics goal of E69, which was not so clear in the June FIFC
meeting, will be discussed in this PAC meeting.
Uno finally presented the review results of E71(NINJA) experiment. The purpose of
E71 is also to measure the neutrino interaction with nuclei for the water target to reduce
the systematic uncertainties of the T2K experiment. In particular, E71 will measure thecontribution from 2 nucleon interaction (2p2h) using the emulsion technique. FIFC
reviewed and concluded that there is no serious technical issue on E71 experimental
apparatus, which is an emulsion cloud chamber in combination with other detectors.
FIFC expects that the achievability of the physics goal of E71, which was not so clear inJune FIFC meeting, will be discussed in this PAC meeting.
Discussions at the FIFC meeting are summarized in detail in a separate report.

2-6 Hadron Hall & SX Beam Status and Target R&D Plan (Hitoshi Takahashi, JPARC/KEK)
Hitoshi Takahashi reported on the status and schedule of the Hadron Experimental
Facility. The report included the status of recent beam delivery, construction of the highp/COMET beam lines, and R&D status of the new production target (T1 target).
Takahashi showed the integrated beam power history during the last two cycles of beamtime. In the run from January to February, 2018, about 93% of the planned beam
accumulation was achieved. The E31 experiment was conducted and the first 8-GeV
extraction test was performed for COMET during the beam time. In the June run, 90%of the planned beam was accumulated, and the E62 experiment was conducted. The
accumulated beam power was 1010 kW*days and 1075 kW*days in these periods,
respectively.
An upgrade plan for the T1 target was reported. The next target will be an indirectly
water-cooled type, which is capable of accepting primary beam power of up to 90 kW. It
is now being manufactured and the installation is planned in fall 2019. Furthermore,another type of target, a rotating target operated with direct cooling with water or He
gas, is being developed for the future. This is called a “euro-coin” type target composedof a nickel disk with a gold or platinum edge. The status of the R&D works for this typeof target was reported.
Construction work for the high-p/COMET beam lines is in progress. Within this year,
installation of magnets in the branching section and high-p experimental area will becompleted. Takahashi showed the construction schedule of the high-p beam line. The
beam line is expected to become available in winter JFY2019.

3. EVALUATIONS OF THE PROPOSALS AND STATUS OF THE ONGOING
EXPERIMENTS
E11/E65 (T2K and T2K-II)
The committee heard two talks from the T2K collaboration followed by a report fromthe neutrino beam line upgrade technical advisory committee.
The first talk reported on the 2018 T2K result based on Run9c with 2.62e21 POT in
total (1.49e21 and 1.12e21 for nu-mode and anti-nu-mode, respectively), which were
presented in Neutrino2018. Note that Run9d data will be added late summer to increasenue-bar POT from 1.12e21 to 1.63e21 POT.
T2K precision result on theta_23 continues to prefer maximal mixing, while the result
NOvA showed at Neutrino 2018 shows a slight preference for the second octant. T2K
sensitivity with doubled statistics for NOvA’s best-fit point was shown. As for nue-bar
appearance, 6.5 background events are expected for no oscillations, while 9 events wereobserved. No statement can yet be made given the limited statistics.
The data fit with a reactor constraint finds that a CP-conserving value of delta is outsideof a 2-sigma band for both hierarchies, while the normal neutrino mass hierarchy isweakly favored. There is a slight tension with the NOvA 2018 result on nue-bar
appearance with 18 events observed while 5.3 background events are expected. There
was a discussion with committee members about CC1pi fluctuation in nue appearance
and there was a discussion of the checks currently underway in the same CC1pi channel
in numu disappearance. The committee also heard about the exotic heavy lepton search
and many neutrino interaction measurements. The latter of which, to be measured by
E61, E69 and E71, would be important for further improvement of systematic
uncertainties in the oscillation analysis.
In response to the previous PAC meeting recommendation, T2K gave a summary of thecomplementarity of the NINJA, WAGASCI, ND280-upgrade and E61 efforts to reduce
systematic uncertainties. The committee urges T2K collaboration to consider making aquantitative evaluation of the impact of the proposed measurements to future T2K
results. This may include differential cross sections or measurements as a function ofsome kinematic variable that is not specifically mentioned in the current proposals.
This will help the measurement proponents to better specify the statistical andsystematic uncertainty goals, and in turn to help the laboratory in understanding therunning needs.
The second talk focused on T2K’s running status and future plan.
A total of 9e20 POT was requested for 2018 as Run9 (Oct2017-2018). 9.1e20 POT wasachieved in 131 days allocated. The accelerator complex operators are to becongratulated on delivering more than the requested POT. There is a water leak of 7
liters/day in the cooling system. The leak is somewhere in the He vessel from a horn,most likely horn1, but the precise location has yet to be determined. Horn replacement
can start this Nov 2018 at the earliest and would be ready for neutrino beam by end of
Feb 2019, if needed. If the He vessel is confirmed not to be damaged, then the beam
operation can continue until 2019 summer shutdown and the leak repaired afterwards.
The problems with the ND280 magnet that started in March led to substantial downtime, but were fixed by May 3. There is a concern that the low ND280 livetime will be
a problem, and PAC would like to hear more about a plan to address this issue.
Impact of SK-Gd plan and its schedule was discussed. Currently Super-K is offline forpreparation work of SK-Gd until end of 2018. There will be a 3-step approach for Gdloading;
step-1 preparation for water system (2019Apr-Jun),
step-2 A 3-months period for circulation of pure water using the Gd-water system,
step-3 actual Gd injection, lasting 3-months, after 2019 Oct.
Super-K prefers successive step-2 and step-3, and needs step-3 within JFY2019.
Finally the committee heard a report for Neutrino beam line upgrade technical advisory
held in June 21-22 (see Sec 2-4). After feedback from T2K response, the final reportwill be delivered to the director by the end of July. Similarly, the ND280 upgrade also
needs a focused review. The PAC endorses the recommendations that were presented
on the beamline upgrade review.
T2K indicates a long-term plan to double the statistics before MR power supply upgrade
planned in JFY2021. The PAC suggests an update of the expected cumulative POT vs
date according to the new plan. T2K requests 7.5e20 POT in the first half of 2019, inview of the rapidly changing statistics in NOvA. The committee recognizes the urgencyof this request. Given the current constraints of the beam time availability, however,allocated beam time might be significantly reduced compared with the requested beamtime. The PAC recommends the laboratory management to explore options to restore
the beam time.

E34 (g-2/EDM)
The E34 (g-2) experiment aims to measure the anomalous magnetic moment (g-2) andelectric dipole moment of the muon.
E34 reported progress in many areas. The g-2 theory initiative has reported progress on
improving the hadronic vacuum polarization and light-by-light scattering contributions
and expects to produce a white paper in early 2019. The improved collaboration
organization was shown and is reported to be functioning. The building for thenecessary power for g-2 is being constructed in FY2018. The various steps in theacceleration of the bright muon beam have been demonstrated to 90 keV (with an article

in the CERN Courier and with several papers published including three in 2018). The
next step is to demonstrate acceleration to 1 MeV. The collaboration plans to publish a
TDR summary on the experiment design.
g-2 requests stage-2 approval.
The updated TDR and responses to the recommendations by the PAC and Focused
Review Committee (FRC) were reviewed by the FRC. A report from the FRC has been
given to the PAC recommending stage-2 approval. The PAC suggests that g-2 workwith Lab management to refine the cost estimate and schedule.
Following the recommendation of the FRC, recognizing the tremendous progress by theg-2 collaboration and plans for addressing remaining issues the PAC recommends
stage-2 approval.

E61 (NuPRISM/TITUS)
E61 is a proposal to build a ~1kt intermediate water Cherenkov detector to be used to
study neutrino interactions at various off-axis angles in the T2K neutrino beam line. The
committee heard progress of phase-1 site investigation. Several candidate sites were
found and discussed. From event rate consideration, the closest site has 0.21 for
efficiency at most on-axis due to pile-up with OD veto, but is still acceptable.
Committee heard also update design for lifting structure and mutli-PMT type photosensors. E61 is working closely with the Hyper-Kamiokande collaboration and trying tointegrate as a part of Hyper-K near/intermediate detectors. The committee encourages
E61 to continue the site survey and design work.

E56 (Sterile Neutrino Search)
The JSNS2 experiment (E56) plans to search for eV scale sterile neutrinos using a
stopped muon source significantly improved compared to that used by LSND.
JSNS2 reported significant progress. They showed a schedule for detector constructionin JFY2018 with operation in early JFY2019. They moved the stainless steel tank along
a route similar to the proposed annual movement of the detector with no problems
encountered. The tank has been cleaned and the PMT mounting structures are being
installed. PMTs should be available on the same timescale as the inner acrylic tank laterin JFY2018. Options for filling the detector, lifting it and satisfying the fire safety laws
were discussed with a J-PARC safety working group. Further discussions withregulatory bodies are required.
The collaboration responded to the previous PAC request for a more detailed simulationof the calibration of the detector. While the light yield increases as much as 30% near
the edges of the detector, the effective light yield as observed in the resolution of theMichel spectrum declines significantly in these regions. They showed effects from thedead acrylic region, PMT saturation and after-pulsing. They described very general
options for calibration sources beyond Michel electrons and n-Gd captures. They
showed scintillator quenching data from Daya Bay and JSNS2 simulations that appears
to show some discrepancy in the overlap region from 8-10 MeV. The collaboration has
taken the first steps toward developing a blind analysis strategy, although significantly
more work is required.
JSNS2 requests stage-2 approval.
Given that detector construction is well underway, international partners need fullexperimental approval and securing funding for the second detector likely requires
results from operation of the first detector, and the progress made in understanding
systematic effects, the PAC recommends stage-2 approval.

E14 (KOTO)
E14 is an experiment to search for the CP-violating rare decay K0L→π0νν, whosebranching ratio is predicted in the Standard Model (SM) to be 2.4E-11 with small
theoretical uncertainty. Because of this good theoretical control, measurements of the
branching ratio can explore new physics up to a scale much higher than the TeV energy
range, which makes this search one of the most interesting searches for beyond-SM
physics. Compared to the last PAC presentation, the collaboration optimized
background rejection further and tailored the signal region. The backgroundexpectation in the 2015 data set is 0.40±0.18 events, dominated by hadron cluster
background. The single-event sensitivity (SES) is 1.3E-9, just below the Grossman-Nirlimit inferred from the charged kaon decay. Recently they unblinded the signal box,
and found no event in the signal region, giving a 90% CL upper limit of 3E-9, which
was presented in the major conferences ICHEP and FPCP this summer.
Concerning the 2016-18 data analysis, most runs have been processed except for themost recent Run 79. The analysis now focuses on the background reduction andestimation. In the 2018 summer shutdown, they will attach MPPCs on the front face ofCsI crystals, which should help further reduce the hadron cluster background. This
crystal configuration equipped with MPPC was tested with a beam at RCNP. They will
also install new charged veto inside the beam pipe.
A projection on the SES has been made with certain assumptions on the background
reduction, beam power increase, reduced veto timing width and reduced accidental rate.
By 2020 the sensitivity will reach around 1E-10 and by 2028, which is at the level ofthe SM prediction. They identified possible path to reach this background level. The
PAC appreciates seeing these projections and encourages the collaboration to work
together with the lab management to further develop the plan to reach the SM levelsensitivity.
The PAC congratulates E14 on the completion of the 2015 data analysis andencourages to publish it as soon as possible. The PAC encourages a focused effort tounderstand and minimize backgrounds in the 2016-18 data set as soon as possible. The
PAC would like to see their readiness to run in 2019 after their summer 2018 upgradework and looks forward to a report at the next meeting. The PAC recognizes theuniqueness of the experiment in the search for new physics and the importance of theinternational collaboration from US, Korea, Russia and Taiwan in pursuing theexperiment under higher beam power in coming years.
The collaboration requests 0.5 months of neutron run, and 1.5 months of physics run
before summer 2019. The PAC supports this request.

E40 (Sp)The E40 experiment measures the Σ±p cross section at the K1.8 beam line using the
KURAMA spectrometer augmented with a new detector system (CATCH) for scatteredprotons. Isospin separation will be provided by measurements of Σ+ + p → Σ+ + p and Σ+ p → Σ- + p along with Σ- + p → Λ + n. These data will be of vital importance to ourunderstanding of nuclear matter at high density relevant to recent and future
observations of neutron star mergers.
At the previous PAC meeting, the PAC recommended a minimum of commissioning
and initial data taking in the Σ- + p mode during the June 2018 running period. In thisPAC meeting, the E40 collaboration reported on the June run. The allocated beam timewas 87 hours in total including 2 days of physics data taking. Σ- particles are clearly
identified, and the number of produced Σ- was 1 x 106 in 2 days. This number is muchlarger than the total Σ- observed in KEK E289 experiment, which was 1.8 x 105 in total.
By tuning the parameters in SCH (segmented hodoscope), Σ- number can be increased
from 30 Σ-/spill to 54 Σ-/spill, close to the designed yield. Commissioning of CATCH is
also made, and it is confirmed to work stably.
The PAC considers that the June 2018 run was successful and encouraging. Also the
PAC finds that the CLAS collaboration at J-Lab has the capability to analyze Σ+preaction in the near future.
The PAC recommends that E40 should take data at the next earliest opportunity given
the potential competition with other experiments. Given the current constraints of thebeam time availability, allocated beam time might be reduced compared with therequested beam time. The PAC recommends the lab. management to explore the options
to restore the beam time.

P73 (Weak Decay Lifetime)

The lightest strange baryonic nuclear system is the hypertriton, . Like the deuterium or
the tritium nucleus for conventional baryon interactions, the provides an importantbenchmark for any strong interaction theory dealing with strange baryons. Its small Lbinding energy BL of only 130 keV found in emulsion studies implies that the L
hyperon has a rather extended wave function. Recently, several heavy-ion collisionexperiments (STAR at RHIC, HypHI at GSI, and ALICE at LHC) reported lifetime
significantly shorter than the free L lifetime. The combination of such a short lifetimeon one hand and, on the other hand, the small binding energy presents one of the mostintriguing puzzles in hypernuclear physics.
P73 aims at a novel precision measurement of the lifetime which does not rely on the
decay vertex distribution as in the recent heavy ion studies. Instead, P73 proposes a
direct measurement of the decay time distribution in the 3He(K-, π0) reaction. The startsignal for the measurement of the time delay caused by the weak decay of thehypertriton, is provided by the incoming K- beam particle, the stop signal is deduced
from the tracking and timing information of the p- emitted in the pionic two-body decay® 3He+p-. The different technique used in this experiment will provide an importantresult on this topic.
Presently, there are several activities ongoing to provide a more precise value for thehypertriton binding energy. Therefore, the proposed experiment is very timely. The
experiment makes use of a Cylindrical Detector System (CDS) and a 3He target system
previously used in J-PARC E15/E31 experiments. The setup will be complemented by ahadron-blind calorimeter installed in the very forward region to detect p0®gg decays.
The detection of high energy (> 600 MeV) g-signals from the p0 decay will indicate theproduction of a L hyperon with small recoil momentum which eventually may form ahypertriton.
In order to proceed to Stage-1 status recommendation, the PAC encourages the P73
collaboration to submit an updated proposal with detailed descriptions of the experiment,
including improved Monte Carlo calculations and more details on the setup and analysis
method. The beam momentum and the setup (in particular, the position and the size ofthe target cell and the PbF2 calorimeter) should be carefully optimized so that the best
accuracy is obtained. While the statistical uncertainty of this new lifetime measurement
seems to be very competitive, P73 should explain how possible systematic uncertainties
can be controlled and to what level they may eventually be eliminated. It should also
provide more information on possible background, which may, for example, be causedby K- decays traversing the detection system.

E69 (WAGASHI/BabyMIND)
The E69 experiment (WAGASCI/BabyMIND) proposes a neutrino interaction
measurement on the water and the CH targets in the T2K neutrino beam line. The
results will be useful to improve systematic errors due to neutrino interaction
uncertainty in the T2K analysis. The detector consists of the Proton Module and the
WAGASCI module, the 3-D Scibar readout planes embedded in the water. The stack of
WAGASHI / Proton / WAGASHI modules are followed by BabyMIND magnetizediron muon spectrometer providing muon momentum measurement.

The committee recognized that E69 will be fully integrated into T2K collaboration as
one of sub-systems under MOU. This allows analysis coordination under the T2K
analysis convener and collaboration responsibility for the operation and maintenancework. The committee appreciated this decision.
The committee heard excellent progress in the pilot experiment T59 for R&D work foreach component of E69 detector, MC works and expected improvement for thesystematic errors in the T2K oscillation analysis. The committee was convinced that thissubstantial achievement readies E69 for the real experiment. The committee further
asked what was the specific deliverable from E69 and how to measure differential
neutrino cross section on the water. The detailed explanation was given in the closed
session. The key analysis is the flux subtraction method combining measurements at thetwo different off-axes of T2K ND280 and E69 both with water and CH targets. The
committee found that the method should work reasonably well in the kinematic regions
where the acceptances can be made to be similar but encourages further efforts tominimize model dependence in the measurement. The group requests stage-2 approvaland neutrino and anti-neutrino beams of one year for each (each for >5e20POT). The
committee understood that stage-2 approval is required for massive installation work of
the detector in summer 2018. Considering the matureness of the detector preparation,
the physics impact on T2K and full integration to the T2K collaboration, the committee
recommends stage-2 approval.

E71 (NINJA)
E71 (NINJA) is an experiment to study neutrino-water interactions with an emulsionwater sandwich detector. Thanks to the micro-vertexing capability of the emulsion
technique, especially for short proton tracks, the stated experimental goal is to focus on
verification of “2p2h interactions” on oxygen and an exclusive precise measurement of
ne interactions with oxygen nuclei. Both of these measurements can in principle reduce
the uncertainty due to neutrino-nuclear interactions used in the T2K oscillation analyses.
The conceptual design is an Emulsion Cloud Chamber interleaved with water-layers
followed by a precision (SciFi) tracker with timing information, placed in front of an
INGRID module to measure muon momentum. The committee heard various
achievements in pilot experiments with 1-60 kg detector masses T60/T66/T68 and thecurrent status of E71 preparation. The committee had a positive impression that any
technical preparation, such as film refreshing, water-ECC construction, event matchingwith SFT/IGRID and demonstration of real analysis results, was successfully addressed.
At this meeting FIFC reported that they found no serious technical issues for E71 setup.
The committee is glad to see the MOU with T2K and the successful grant application.
The group requests stage-2 approval to proceed with further preparation of detector. The
committee, however, could not fully assess what the NINJA’s primary deliverables are
and how this will benefit the T2K analysis. For example, the signal being measured was
not clear and its definition needs to be clarified.

NINJA’s beam request was for neutrino mode only in order to detect short proton tracks
in final states and due to the smaller contamination of wrong-sign neutrinos, because inanti-neutrino mode, the “2p2h process” is assumed to produce neutrons in the final state,
which would not be visible in NINJA. On the other hand a measurement of electron
neutrino charged current interactions with and without a proton in the final state might
be of particular interest to get better constraint on the antineutrino to neutrino ratio forthat flavor of neutrinos.
The committee notes that “verifying 2p2h interactions” is not a model-independent goal,
and a more appropriate goal might be something more accurately described as a“measurement of the cross section for charged current zero pion events that have two
protons identified in the final state”. The committee suggests that NINJA consider what
measurement can be made of that two-proton process that would be model independent,
which can then be used as a check on the “2p2h models” that T2K is considering using
in their oscillation analysis.
The committee recommends stage-2 approval if the NINJA collaboration is able toreasonably address the following concerns. Preliminary reply from the group should be
provided by the end of October 2018.
1) Please describe the specific deliverable that you propose to measure,
preferably one that can be defined in a model-independent way. Is the goal tomeasure a flux-integrated absolute measurement of the cross section for eventswith two protons in the final state above some proton momentum threshold?
Is it a ratio of the 2-proton to 1-proton charged current zero pion events as afunction of muon longitudinal momentum?
Please describe the strategy to use the exclusive measurement including short
tracks, and what are the systematic errors, for example two-proton event signal
and backgrounds? Will this be a differential cross section, and if so, as afunction of what kinematic variable?
2) Are there any measurements that are useful to T2K that could be made in theantineutrino mode of the beam? If so, then please state the specific (again,
preferably model-independent) deliverable and what the statistical andsystematic uncertainties might be on that deliverable.

E21 (COMET)The E21 (COMET) experiment aims to observe charged lepton flavor violation throughthe µ to e transition in the muonic Al atom. The status report presented to PAC mostly
concerns Phase I of the program, which uses a lower intensity beam and a simplified
apparatus. Phase I already offers the possibility to probe for new physics with a 100 foldimproved sensitivity, assuming 150 days of data taking.
COMET, a large international collaboration (17 countries) of about 200 members,continues to expand, with three new institutions joining in 2018.
The 8 GeV test of the proton extinction ratio in between bunches took place after theprevious PAC meeting. In this test the 8 GeV beam emittance turned out to be better
than expected. After careful tuning of the extraction scheme of the four acceleration
buckets in MR, an acceptable extinction ratio was achieved for the first three bunches,but not for the last bucket (K4 rear), as of today. They observed proton leakage in thebucket during the 1st 100 milliseconds, which should be clarified and removed in futureaccelerator study. The PAC looks forward to learning more in January 2019 about thestatus of this issue, but considers that a very important milestone has already beenachieved.
COMET has set up an editorial board in order to release the TDR of Phase I by the endof the year, including a ~100-page summary meant for publication. In the meantime, thegroup is preparing the input to the European Strategy update (deadline 18th of December2018), which implies revisiting Phase-II expectations.
On the detector side, prototypes, R&D and tests are proceeding well. At some point, themultiple tracking approaches should be unified. A presentation of the status of theexperiment’s preparations for Physics analysis would be welcome: organization,
resource needs, reconstruction software, detector performances, and, more generally,
analysis plans.
The PAC congratulates the COMET collaboration for its steady progresses andachievements.

E45 (Baryon PWA)
The E45 experiment aims to measure the πN→ππN and πN→KY reactions at center ofmass energies in the range W=1.54 - 2.15 GeV in order to clarify the existence andproperties of nucleon resonances up to 2 GeV through partial wave analysis (PWA).
The experiment fully utilizes the newly-constructed 4π-detector, the Hyperon
Spectrometer (the superconducting Helmholtz magnet and the time projection chamber,
HypTPC), which will be used for the stage-2 approved experiment, E42 (H dibaryon
search). The E45 experiment will be conducted at the K1.8 beam line with π± beams of~106 per spill with a small momentum bite by changing the beam momentum from 0.74
to 1.98 GeV/c with 0.02 or 0.025 GeV/c steps.
In the PAC meeting, the group addressed the questions raised in the previous PAC
report. As for the physics case in the proposed experiment, an example was given toshow possible large effects of a new resonance on the total cross sections and the mass
distributions in the ππN channel. It was mentioned that the ππN channel data will beanalyzed via coupled-channel PWA by three different theory groups, which the PAC
found to be quite important to avoid possible ambiguities from different theoreticaltreatments and to ensure the reliability of the analysis. The PAC also found that thestatistical quality of the data and the beam momentum steps seem to be reasonable. The
group stressed that possible systematic errors in the proposed experiment can besuppressed by comparing the pion elastic scattering data with the existing high-quality
world data. They also demonstrated that clear identification of hyperon production
channels is possible via the kaon missing mass spectrum. The PAC recognized thatmost of the questions are reasonably answered.
Preparation of the apparatus and the detectors is going smoothly. The TDR has been
updated on target installation, segmentation of the TPC hodoscope, etc., and reviewed
again by FIFC with a satisfactory response. The group recently studied performance ofthe HypTPC with intense beams at HIMAC and found it working well at 1 MHz beam
intensity as expected in the E45 experiment. A long-term test of the superconducting
magnet as well as a test of the liquid hydrogen target is also in progress. The experimentwill be ready to run in 2019.
The PAC understands the importance of collecting the ππN channel data and expects
E45 to make significant contribution in the exploration of the nucleon resonancespectrum. The PAC also appreciates their steady progress of the preparation for theexperiment. Therefore, the PAC recommends stage 2 approval to E45. Considering theheavy demands for MR beam time, the PAC requests that the group further examine
ways to reduce the total beam time requested and to find an efficient running scheme,
including quick but careful beam tuning.

E36 (Lepton Universality)
E36 (Lepton Universality) main goal is to measure the ratio of branching ratio
Br(K+→e+ν) over Br(K+→µ+ ν). The collaboration aims to match the current
measurement precision (but with different systematics), which shows agreement with
the Standard Model prediction at 0.4% level. The deviations from the Standard Model
recently observed in lepton universality violating B decays make this measurement
highly relevant. In addition, the tests of lepton universality is complementary to
searches for lepton flavor violation performed e.g. by COMET.
Preliminary results of the data analysis were presented in this status report. In particular
the Kl2ee decays were observed which are a background process for the Dark Photon
search in E36.
The PAC strongly encourages a timely completion of the analysis and expects a status
report on the final analysis, and its corresponding publication plan, to be presented at
the January 2019 meeting.

E03 (X-ray from X- Atom)The E03 experiment aims at the world’s first observation of X-rays from X-atoms. Fromthe energy shift and the width of the X-rays, information on the real and the imaginaryparts of the X-nucleus optical potential is obtained. It provides constraints on the Ξ-nucleon potential, which may be of importance in the discussion on the structure ofheavy neutron stars. As a first step towards the future systematic studies, E03 willmeasure the X-rays from the X-Fe atom. The X particle will be produced via a (K-, K+)
reaction on an iron target and will stop in the target, forming X -Fe atoms. The
transitions will be identified by the measurement of the X-rays by a Ge detector array.
Experiment E03 proposes a two-phase strategy. In the first phase, the experimental
conditions will be optimized using about 10% of the beam time measuring the transition
from the n=7 to the n=6 states, which is rather easy to observe, although it is notexpected to show a significant shift and width due to the strong interaction between X
and Fe. In the second phase the transition from the n=6 state to the n=5 state will beobserved.
The commissioning runs were performed in June 2017 and Feb. 2018 and the conditionsof the gamma-ray measurements were carefully examined. The distance of the gammaray detector from the target has been optimized to be 6 cm in a compromise between thedetection efficiency and the over-killing by Compton suppression. It was confirmed thata reasonable detection efficiency and signal to noise ratio are obtained with thiscondition as expected.
The proponents requested 15 days of beam time together with 3 days for thecommissioning and calibration runs after the E40 experiment, with a switchover time offour months. The allocation of the beam time after completion of the E40 experimentshould be considered in the next PAC.

E07 (Double Strangeness)
The hybrid-emulsion experiment E07 is a unique experiment aiming at the precision
study of the ground state masses of light double-hypernuclei. This is of importance not
only because of the intrinsic interest in these novel systems but because of theconstraints such data will place on the role of hyperons in heavy neutron stars.
After the successful irradiation of the emulsion plates in 2017, the PAC is satisfied withthe significant progress in the successful processing of the emulsion plates. The
committee congratulates the collaboration on the detection of the first signals of doubly
strange systems including 5 double Lambda events and 5 twin events. The PAC hopesthat the manpower presently working on the analysis can be maintained in future. In
order to guarantee the transfer of knowledge, a detailed documentation of the data andthe analysis procedure seems mandatory and securing continuous support for humanresources working on the analysis during the next years is recommended.
The PAC is very pleased to see that E07 is starting to explore the full scientific potentialof the excellent data contained in the emulsions. The committee hopes that theinteresting search for X-ray transitions in heavy X- atoms will only be the first step tobroaden the physics program of E07. The list of possible topics may, e.g., include asearch for decays of single hypernuclei, the elastic scattering of X- hyperons or theinteractions of energetic X- hyperons with nuclei contained in the nuclear emulsions.

E16 (Spectral Change of Vector Mesons in Nuclei)
E16 is an experiment to measure the spectral function of vector mesons at finite density
via the e-e+ invariant mass spectrum. The spectral function of hadrons at finite
temperature and/or density is one of the fundamental and important observables in QCD
matter physics.
The dilepton spectrum at high temperature displays a broad accumulation of low massstrength and other finite temperature effects. By comparison, the KEK E325 experimentshowed the modification of the spectral function at finite density, which may beinterpreted as a mass shift of meson. It is valuable to confirm/update this “mass shift”,
and the high momentum beam line should be ready at the beginning of 2020.
In the 2017 July PAC meeting, the PAC recommended Stage-2 approval for Run0 andencouraged the group to thoroughly review the strategy of beam commissioning in close
cooperation with the beamline team. In the current PAC meeting, the E16 collaboration
presented the updated strategy and the schedule toward Run0 expecting the beam timeat the beginning of 2020. With the aid of newly approved grant-in-aid (KAKENHI
Kiban S), the previous Run0 configuration (6(SSD)+6(GTR)+2(HBD)+2(LG)) is
updated to a new configuration (6(SSD)+8(GTR)+4(HBD)+4(LG)). Three studentsjoined the collaboration and are working on the detector, firmware and ASD. The PAC
understood that the Run0 can be ready before the possible early 2020 beam time. With
the approved 40 shifts x 8 hours (10 shifts of beam halo minimization and 30 shifts ofdetector commissioning (including background study and data taking)), the number of
produced ω meson would be comparable to that in the KEK E325 experiment.
The PAC is concerned about the tight schedule of the preparation. Installation ofexperimental apparatus has to be finished before the high-p beam line becomes readyand the ceiling is closed. And the magnetic field mapping, where detailed scan is crucial
to obtain good momentum resolution, is likely to be time consuming and should be
carefully considered in their time schedule. The PAC recommends E16 to have close
contact with the hadron hall staff members for the development of the detailed schedule.
The stage-2 approval for Run-1 will be discussed based on the results of Run-0. It isgood news that in Run1, 6(SSD)+8(GTR)+6(HBD)+6(LG) configuration is secured by
the grant. The long beam time request (160 shifts x 8 hours for Run1 and 320 shifts forRun2) is of concern.

E62 (TES)
The result of the E62 experiment performed in June 2018 was reported. The X-rays
from kaonic 4He and 3He atoms emitted in the transition from the 3d to the 2p orbitals
were successfully observed, which is relevant to resolve the long-standing problem on
the depth of the K- nucleus potential. Since the widths of the transitions are predicted to
be as small as 2eV, a high energy-resolution measurement using superconducting
transition-edge-sensors (TES) was introduced.
The PAC congratulates the successful observation of the X-rays using the TES detector
for the first time in this field and is looking forward to the result of the analysis, which
is now ongoing.

E57 (SDD)
E57 aims at a pioneering measurement of X-rays from K--d atoms. A precision
measurement of the shift and width of the 1s state by the strong interaction will provide
unique information on the kaon-neutron interaction at threshold. Prior to stage-2
approval, the collaboration intends to validate their Monte Carlo estimates ofbackgrounds by a short test measurement with a liquid hydrogen target. For this pilot
experiment with hydrogen, E57 asks for 3.0 days for beam tuning and detector
commissioning, to be followed by a short 3.5 days data taking run.
The PAC is happy to see that the preparation for the pilot run of E57 is continuingsmoothly. All 48 required Silicon Drift Detectors are available at J-PARC and will
undergo final tests until the end of 2018. The installation of all other components of theexperiment is on time and can be finished during the last quarter of 2018. The final testsof the complete setup will be performed early 2019.
The PAC acknowledges the readiness of E57 for the test run. Considering the fact that
this relatively short measurement can provide already a very competitive measurementof the hadronic shift and width of kaonic hydrogen, the committee recommends the
allocation of the requested beamtime (6.5 days) during the hadron hall running period
envisaged for March/April 2019.

4. Summary of BEAM TIME ALLOCATION from October 2018 to June 2019
The PAC heard that operation period of MR for users in the latter half of FY2018 isone-month due to funding constraints. Full operation, in the new JFY, from April toJune in 2019 is planned. In total, 4 months of operation is currently planned until next
summer. The Super K tank repair work will continue until the end of CY2018 and T2K
can take beam from January. The KOTO detector upgrade work will complete in
February 2019 and they can take beam from March. No beam for HD can be delivered
beginning May 2019 to allow enough time for cooling before the planned HD target
replacement later in the year. Assuming this tentative accelerator operation schedule,

97.5 days of user operation is expected during the 4-months period from March to Junein 2019.
The PAC recommends that the completion of the E40 experiment, with both S+ and Sphysics data taken, as well as the E57 commissioning run take place before Summer
2019. It recommends an allocation of 47.5 days for these two experiments and the
KOTO experiment. The remaining 50 days are recommended for allocation for the T2K
experiment. Other stage-2 approved experiments in the near detector hall should runparasitically with T2K. Both allocations include the necessary accelerator tuning andstudies to establish stable/improved user operation.
This schedule curtails the allocation requests of E40 and T2K due to the constrained
beam availability. If additional operation becomes possible in JFY2018 with additional
funding, restoration of the E40 full allocation request (additional 9 days) should beprioritized followed by additional running for T2K.

5. DATES FOR THE NEXT J-PARC PAC MEETINGThe next J-PARC PAC meeting will be held January 16-18, 2019.

6. FOR THIS MEETING, THE J-PARC PAC RECEIVED THE FOLLOWINGDOCUMENTS:
ØØ

Minutes of the 25th J-PARC PAC meeting held on 15-17 January, 2018
(KEK/J-PARC-PAC 2018-14)
ProposalsoØP73 experiment:
andMesonic Weak Decay Lifetime
3,4- 0
Measurement with He(K ,p ) Reaction (KEK/J-PARC-PAC 2018-24)

Technical Design ReportsoUpdate of Technical Design Report (TDR): Searching for a Sterile
Neutrino at J-PARC MLF (E56, JSNS2) (KEK/J-PARC-PAC 2018-15)oTechnical Design Report (TDR): Study of neutrino-nucleus
interaction at around 1GeV using cuboid lattice neutrino detector,
WAGASCI, muon range detectors and magnetized spectrometer, BabyMIND, at J-PARC neutrino monitor hall (E69, WAGASCI/Baby-MIND)(KEK/J-PARC-PAC 2018-17)oTechnical Design Report on the Experiment E45 (KEK/J-PARCPAC 2018-18)

o
Ø

Ø

J-PARC E71 Technical Design Report (KEK/J-PARC-PAC 201819)

Reportso

E56 response to the minutes of the 25th PAC (KEK/J-PARC-PAC
2018-16)oSummary of Reports of the Technical Design Focused Review
Committee of the Updated J-PARC E34 g-2 Experiment Technical
Design Report (KEK/J-PARC-PAC 2018-20)o

E65 (T2K-II) Status report: J-PARC Neutrino Beamline UpgradeTechnical Design Report (submitted to the dedicated review committee)(KEK/J-PARC-PAC 2018-25)oReport from J-PARC Neutrino Beam Line Upgrade TechnicalAdvisory Committee Meeting (KEK/J-PARC-PAC 2018-26)

Letter of Intent
Decay Pion Spectroscopy ofoproduced by 7Li (K-, K+) reactions(KEK/J-PARC-PAC 2018-23)
Ø

MOU’s
o

Memorandum of Understanding (MoU) between T2K
collaboration and the NINJA collaboration (KEK/J-PARC-PAC 201821)

oIntegration of WAGASCI (E69) experiment into the T2K
experiment (KEK/J-PARC-PAC 2018-22)