Physicists confirmed the acceleration of the proton beam at the first sets of Linac in J-PARC, a world-class high intensity proton synchrotron accelerator, on November 21. This success marks the beginning of the series of accelerator operations tests leading to the rest of the facility including 3 GeV and 50 GeV proton synchrotrons, jointly build by two national agencies, Japan Atomic Energy Agency (JAEA) and High Energy Accelerator Research Organization (KEK).
 
Negatively charged hydrogen atoms are successfully accelerated to three million electron volt with a peak current of 5 milliampere at the first stage of the J-PARC Linac. "We accelerate negatively charged hydrogen in the Linac to inject the beam smoothly into the circular synchrotron," says the accelerator manager Kazuo Hasegawa. Circulating protons (positive charge) and negatively charged hydrogen are curved into opposite directions and merge into a single orbit. Later, electrons are stripped off from the hydrogen with a thin foil.
 
"The Linac is 330 m in total length, and we will complete the first 120 m with the cavities in the first phase of the project by summer next year," Hasegawa continues. "Today we have succeeded the acceleration of protons at the very first cavity, called Radio Frequency Quadruple (RFQ). We will continue to work on the rest of the cavities, such as Drift Tube Linac (DTL) and Separated-type Drift Tube Linac (SDTL). Combined together, we will accelerate the protons to 180 million electronvolt, roughly the half of the speed of light."
 
Two research organizations started the construction of J-PARC since 2001, and will continue to build a kilometer wide accelerator complex by 2009, located in the Tokai Campus of JAEA roughly 100 km northeast of Tokyo. The 3 GeV rapid cycling synchrotron (RCS) will be used for a 1 MW neutron spallation source and muon source, and the 50 GeV synchrotron with a 0.75 MW proton beam will generates various secondary particles, such as neutrinos for T2K experiments, and hadron beams for the study of particle rare decays.
 
"In 2008, J-PARC will start providing a wide range of international research opportunities, both in the fundamental research, the applied research and for new technology," says J-PARC director Shoji Nagamiya. "High intensity neutrino beam to Super-Kamiokande, which is 295 km west to J-PARC, will open the door to a new phase of neutrino research. The analysis power for materials research with the neutron scattering facility will be in parallel to the SNS at ORNL in the USA. Abilities of the muon scattering facility and the kaon factory will be unparalleled for the decade to come. We welcome researchers around the world in various fields, including the particle and nuclear physics, materials science, chemistry, biology, life science, engineering, information and electronics technology, and even medical. We look forward for the international collaborations."