Construction is well under way in Japan on the new facility to send neutrinos from J-PARC to the Super-Kamiokande detector nearly 300 km away. --> more

Birth of Pulsed Neutrons in J-PARC (J-PARC Newsletter Special Issue(Birth of neutrons)-2008/5/30-)
On May 30th, 2008. At 14:25, a shot of 3GeV protons from RCS (3 GeV synchrotron) was injected to the mercury target at MLF. http://j-parc.jp/MatLife/1stBeam/PromptReport.JPG . 
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MR: Successful injection of 3GeV proton beam, RF captured and extraction
At 22:27 of May 22nd 2008, the 3 GeV proton beams from the RCS (3GeV proton synchrotron) were successfully injected into the Main Ring (50GeV proton synchrotron). The beam was captured by RF and extracted to the beam dump after 1000 turns. The day after, the beam storage time was extended up to 1 second. It is the major milestone for the J-PARC. The next step is to accelerate beams to 30GeV (Phase I) and to extract beams to the experimental holes, which will start in the end of this year. (by nh 2008.5.27)

Successful in accelerating a proton beam to the design energy of 3 GeV in the RCS at J-PARC(October 31, 2007)

Protons are successfully accelerated at the J-PARC Linac(PressRelease 2007/01/31)

J-PARC Project Newsletter (2007/1/24)
The J-PARC linac accelerated the H-minus beam up to the energy of 181 MeV

J-PARC Linac Accelerated Its First Beam(PressRelease 2006/11/22)

• KEK: http://www.kek.jp/intra-e/press/2006/J-PARCLinac.html
• JAEA: http://www.jaea.go.jp/english/news/p061127/index.shtml

J-PARC Started Magnets Installation to 50GeV Synchrotron (Photo Nov. 15, 2005) (KEK NEWS TOPICS)

The proton accelerator facility under construction was opened to the press. Photo -Jan. 26, 2005-

The negative hydrogen ion beam has been accelerated up to 19.7MeV at Drift-Tube Linac.

• JAERI News Release
• KEK Press Release( In Japanese)
  

J-PARC Newsletter Hilight

ACCELERATOR KEEPS AVAILABILITY HIGHER THAN 92 % IN USER OPERATIONS FOR NEUTRON, MUON AND NEUTRINO.---more
(J-PARC Project Newsletter No.41, Aug.4, 2010)

AVAILABILITY EXCEEDS 92 % IN 120 KW OPERATION FOR THE COMMON USE OF MLF (MATERIAL AND LIFE SCIENCE FACILITY).---more
(J-PARC Project Newsletter No.40, June.8, 2010)

THE FIRST T2K NEUTRINO EVENT OBSERVED AT SUPER-KAMIOKANDE ---more
(J-PARC Project Newsletter -Special Issue-, Mar. 5, 2010)

SUCCESS IN 300 kW TEST OPERATION OF RCS (3-GeV Rapid Cycling Synchrotron) ---more
(J-PARC Project Newsletter No.39, Mar. 1, 2010)

Beam commisioning restarted with steady improvement of RFQ (Radio-Frequency Quadrupole) LINAC---more
(J-PARC Project Newsletter No.38, Nov. 13, 2009)

Success of Extraction to Neutrino Target from MR---more
(J-PARC Project Newsletter No.37, July 23, 2009)

Extraction of 30 GeV proton beam to hadron beam dump---more
(J-PARC Project Newsletter No.36, May 7, 2009)

Success of 30GeV acceleration and extraction in MR ---more
(J-PARC Project Newsletter No.35, Feb. 4, 2009)

EXCITING NEWS FROM THE 3 GEV ACCELERATOR April15, 2008
J-PARC Project Newsletter #32(April15, 2008) [Overview] by Shoji NAGAMIYA

At the end of October we had a successful acceleration in the
3 GeV ring. Four months later, at the end of February of 2008, the beam power per pulse reached 5 kW/pulse. Since the 3 GeV ring will operate at 25 Hz (25 pulses per second), this power/pulse is equivalent to 130 kW per second if 25 pulses were accelerated.
Since the neutron target is not yet ready to accept the primary proton beam, the accelerator crew decided to deliver 50 kW beams to a beam dump for about four minutes before the accelerator operation was terminated for the March shutdown for machine inspection. We had not expected to reach such a high power level within the first four-month period after the injection and extraction were achieved at 3 GeV. It is, therefore, exciting news for us.
Note that the goal at 3 GeV is 600 kW by using the present Linac energy and 1 MW by boosting the Linac energy to 400 MeV.

J-PARC Project Newsletter #32 April 15, 2008
ONE SHOT OF 1.07E13 PROTONS WAS EXTRACTED FROM THE RCS AT 3 GeV, WITH A MODEST BEAM LOSS, CORRESPONDING TO THE BEAM POWER OF 130 kW, IF OPERATED AT DESIGNED REPETITION RATE OF 25 Hz.

J-PARC Project Newsletter #31 Feb., 2008
RADIATION SAFETY INSPECTION FOR THE RCS WAS CLEARED, BEING READY FOR THE NEXT STEP TO INJECT THE TEST BEAM TO BOTH THE NEUTRON PRODUCTION TARGET IN THE MLF AND MR

J-PARC Special News and J-PARC Newsletter No.30 dispatch, Nov. 1, 2007
The accelerator group succeeded in accelerating the beams from the Linac to the design beam energy of 3 GeV via the Rapid-Cycling Synchrotron Special news from J-PARC project on 2007.10.31.

J-PARC Project Newsletter #30 Oct. 30, 2007
THE RCS STARTED THE BEAM COMMISSIONING AS SCHEDULED
INTERLOCK SYSTEMS ARE READY FOR THE BEAM COMMISSIONING OF THE RCS

J-PARC newsletter #29 July 23, 2007
THE BEAM COMMISSIONING OF THE RCS IS COMING SOON.
THE LINAC IS READY TO INJECT, WHILE THE RCS IS TRYING TO SOLVE THE ELECTROMAGNETIC COMPATIBILITY ISSUE WITH ALL THE ACTIVE ELEMENTS.
J-PARC newsletter #28 May 28, 2007
THE LINAC ACCELERATED THE NEGATIVE HYDROGEN BEAM TO THE DESIGN ENERGY OF 181 MEV THREE MONTHS BEFORE SCHEDULED.
J-PARC Newsletter No.27 dispatch (Feb 8, 2007)
THE LINAC BEAM COMMISSIONING STARTED AS SCHEDULED,ACCELERATING THE BEAMS UP TO 50 MEV BY THE END OF 2006.
J-PARC newsletter #26 Oct. 19, 2006
THE RADIATION SAFETY AUTHORITY ISSUED THE PERMISSION FOR THE J-PARC CENTER TO START THE BEAM COMMISSIONING.THE RCS RF SYSTEM WAS SUCCESSFULLY POWER-TESTED FOR 1,000 HOURS.
J-PARC newsletter #25 31 July, 2006
THE J-PARC RING RF TEAM IS BREAKING THROUGH MANY TECHNOLOGICAL DIFFICULTIES
J-PARC newsletter #24 17 May 2006
THE RING RF TEAM IS FOCUSING ON FINDING THE METHOD OF CUTTING THE MAGNETIC ALLOY CORES, WHICH CAN STAND THE LONG-TERM HIGH POWER LOADING.
J-PARC Newsletter #23 Feb. 1, 2006
THE INSTALLATION OF THE ACCELERATOR COMPONENTS IS IN PROGRESS FOR ALL THREE ACCELERATORS, WHILE SOME R&D IS STILL NECESSARY FOR SOME COMPONENTS INSTALLATION OF CONTROL SYSTEMS FOR LINAC IS IN PROGRESS.
J-PARC Newsletter #22 Oct 28, 2005
THE CERAMICS VACUUM CHAMBERS FOR THE BENDING MAGNETS OF THE 1-MW RAPID-CYCLING SYNCHROTRON ARE NOW UNDER MASS PRODUCTION
J-PARC Newsletter #21 Aug., 2005 THE RFQ LINAC AND DTL WERE TRANSPORTED FROM KEK TSUKUBA SITE TO JAERI TOKAI SITE.
J-PARC Newsletter #20 May, 2005
REPORTS FROM ALL THE FRONTLINES OF THE ACCELERATOR CONSTRUCTION BATTLEFIELD
J-PARC Newsletter #19 Feb, 2005

▼April, 2007

RCS: Between the linac test run, the RCS quadrupole, bending magnets and their power supplies are continuously tested. Left photo shows the installation status of the injection area (the beam from the linac coming from the bottom) and right shows that of the extraction area
MR: All bending, quadrupole and sextapole magnet of the MR are installed. Half of the steering magnets are set. The left photo shows a steering magnet (bottom part only) and a beam position monitor.

▼March, 2007
RCS: Major components of the RCS have been installed. The left photo is acceleration cavities and the right is the switching yard from the RCS to the MLF (Materials and Life Science Facility) and the MR.
MR: The injection/extraction system has been tested. They could be highly radio activated and their maintenance is very important. The left shows that the septum magnet, which is the heaviest among the injection system, is set on the linear guide. It allows disconnecting the septum magnet out of the beam line smoothly and safely even with small gap, after semi-remote flange (right photo) separates the connected vacuum chambers.
▼February, 2007
Linac: Early morning of January 24th , 2007, the beam energy of the J-PARC linac reached 180MeV, which is the important milestone of the project. The bellow plot shows comparison between the design value at each beam monitor location (horizontal axis) and the measured energy by TOF (Time-Of-Flight) method (red circle).
RCS: Both quadrupole magnets and its power supplies were tested and the system has been operated with full current under standard pattern of 3.64 seconds period. The bellow shows the MR quadrupole testing area.
▼January, 2007
Both quadrupole magnets and its power supplies were tested and the system has been operated with full current under standard pattern of 3.64 seconds period. The bellow shows the MR quadrupole testing area.
▼December, 2006
A proton beam test has begun on Nov. 20th and the acceleration was confirmed on 21st.. The beam is transported to the RFQ downstream. The machine is operated with 5mA or 30mA beam current, 50usec width and 5Hz repetition.
The magnet power supplies for the 7-familiy quadrupole and bending magnets have been tested in the RCS.
View of power supply test in the magnet power supply room
Installed RCS magnets in the machine tunnel.
▼November, 2006
Klystron test and microwave aging had been continued at the Linac successively. Beam commissioning has begun on November 20th and the first proton beam was accelerated up to 3MeV at RFQ.
The foil exchanger and the shift-bump magnet for the RCS beam injection system have been preparing. The exchange mechanism for the charge-exchange foil The shift-bump magnets for the RCS injection
Installation works of the collimator at the RCS-MR transport line
Installation works of the collimator

KEK NEWS TOPICS
50GeV Magnet Installation Begins (Photo Oct. 27, 2005)

▼October, 2006
A radiation area of the Linac has been set on October 11. After high power test, the linac beam comissioning would be started one by one. A0BT (from SDTL to the arc section) View of the klystron gallery
The installation of the bending, quadrupole and sextupole magnets for the RCS almost finished. Now ceramics ducts for the quadrupoles has been set. The beam collimators, vacuum chambers, the kicker magnet, diagnostic instruments and ring RF would be installed until next February.The beam collimator The kicker magnet tank
In two arc section of the MR and at the 3-50BT line, most of the bending and quadrupole magnets are installed. layout
▼September, 2006
The installation of the ceramics ducts for the RCS bending magnets (BM) proceeds. The 22 ducsts out of 24 have been completed.
The 36 RCS quadrupole magnets out of 60 are carried into the machine tunnel.
▼August, 2006
The collimator system at the 3-50BT line has been installed

The final construction area of the MR machine tunnel is close to completion
▼June, 2006
Vacuum ducts between the bending or quadrupole magnets have been installed and connected to the neighbors.
Installation works of the vacuum instruments.
Magnet alignment works are also proceeding.
▼20051201
Seventeen bending magnets (photo), two quadrupole magnets and some steering magnets for MR (50GeV synchrotron) are transported to their installed position.(right)
▼20051006
View from downtream into the DTL-1 inside. Drift tube (center), stem (supporting the drift tube from the top) and post-coupler (side bar) are seen with three consecutive section.(right)
A titanium vacuum chamber is being installed at L3BT (Linac-RCS Beam Transport) line. Upper yoke of the bending magnet is removed and the magnet alignment is confirmed during the installation procedure.(right)
▼ 20050922
On September 21th, an air-pallet (special cart) has been installed, which transports a bending magnet inside the MR tunnel. This is the first instruments delivery into the MR tunnel.
▼ 20050908
<Magnet and power supplies for MR have been delivered and kept at storage area.
▼20050825
The first ceramic duct has been completed with welding a titanium flange.
▼20050811
The RFQ linac cavity was installed by July 25.(right)

The Linac Krystron gallary (August)

The first ceramic duct for RCS was succeed of electroforming.
20050707
The RFQ linac cavity was transported from KEK on July 6.

The DTLtanks was transported from KEK on June 27.
▼20050526
The Linac Krystron gallery (May)