News

T2K presents hint of CP violation by neutrinos

August 4, 2017

The international T2K Collaboration strengthened its previous hint that the symmetry between matter and antimatter may be violated for neutrino oscillation.  A preliminary analysis of T2K’s latest data rejects the hypothesis that neutrinos and antineutrinos oscillate with the same probability at 95% confidence (2σ) level. With nearly twice the neutrino data in 2017 compared to…

Read More

T2K beam run extension given Stage-1 Status at J-PARC

June 12, 2017

On 30 Sep, 2016, the KEK-IPNS Director and J-PARC Center Director granted stage-1 status to the T2K collaboration’s proposal for an extended beam data run to search for CP violation by neutrinos.  The proposal requests delivery of 20×10²¹ protons-on-target (POT) by 2026, which would allow the possibility of  3 sigma sensitivity for CP violation. In…

Read More

J-PARC delivers 2.0e21 protons on target

March 8, 2017

On March 2, the number of protons delivered to the neutrino target of the T2K experiment by the J-PARC accelerator reached an important milestone: 2×10^21 accumulated since January 2010.  Many thanks are due to the J-PARC directorate and the staff members for their outstanding work to make this possible ! The protons are produced by the J-PARC…

Read More

Koichiro Nishikawa wins 2016 Pontecorvo Prize

March 1, 2017

Professor Koichiro Nishikawa has been awarded the Bruno Pontecorvo Prize for the year 2016. The Bruno Pontecorvo Prize is awarded by the Joint Institute for Nuclear Research (JINR) in Dubna, Russia, for elementary particle physics. The prize commemorates Prof. Bruno Pontecorvo, a pioneering neutrino physicist who worked for many decades at JINR. The Prize was…

Read More

T2K Near Detector Upgrade

February 16, 2017

On February 11, 2017, the T2K Collaboration launched its Near Detector Upgrade project. The upgrade is targeted at reducing systematic errors in T2K’s search for CP violation in the neutrino sector. The current conceptual design will be developed into a technical design, leading to a full proposal, by the end of 2017. The collaboration aims…

Read More

T2K CP violation search results presented at ICHEP 2016

August 6, 2016

The international T2K Collaboration announced today their findings on the symmetry between neutrino and antineutrino oscillation. With nearly twice the antineutrino data in 2016 compared to their initial results using antineutrino data in 2015, T2K has performed a new analysis of all data, fitting both neutrino and antineutrino modes simultaneously. Today’s announcement was made by…

Read More

T2K presents first CP violation search result

July 4, 2016

New data support growing hint of different oscillation probabilities for neutrinos and antineutrinos The T2K Collaboration presented new results on neutrino and antineutrino oscillations at the 27th International Conference on Neutrino Physics and Astrophysics (Neutrino 2016) at Imperial College London.  T2K’s new data continue to prefer maximal mixing in the atmospheric angle (θ23), a value…

Read More

J-PARC Nu Beam Power Exceeds 400 kW!

May 31, 2016

The J-PARC neutrino beam, which provides neutrinos and antineutrinos for the T2K experiment, has exceeded 400 kW beam power.  A new Main Ring accelerator tune allowed the beam power to exceed the 400 kW threshold on May 20, and the T2K beam ran stably above 400 kW from May 23 until May 27, when the…

Read More

T2K run extension being studied

April 14, 2016

The T2K collaboration is considering the improvements in physics sensitivity, especially for CP violation, from an extension of the running time with beam power of ~1.3 MW. An Expression of Interest for the T2K extension was presented to the J-PARC PAC held  January 13-15, 2016.

J-PARC Main Ring upgrade approved

April 14, 2016

A new facility in J-PARC to upgrade the Main Ring accelerator is approved. This facility will house a new power supply system with which the repetition rate of the Main Ring will be doubled―resulting in 750 kW beam power for T2K, with potential to exceed 1 MW.