T2K (Tokai to Kamioka) is a long-baseline neutrino experiment in Japan, and is studying neutrino oscillations. Neutrinos are elementary particles which come in three “flavours”: electron, muon, and tau. They only interact through the weak force, and are very difficult to detect as they rarely interact with matter. Electron neutrinos are produced in large numbers in the Sun, and solar neutrinos can pass all the way through the Earth without interacting.

T2K has made a search for oscillations from muon neutrinos to electron neutrinos, and announced the first experimental indications for them in June 2011. These oscillations had never been observed by any previous experiment. T2K is also making measurements of oscillations from muon neutrinos to tau neutrinos (which have been seen by previous experiments). It will make the most accurate measurements to date of the probability of these oscillations and of the difference between the masses of two of the neutrinos (to be precise, T2K measures the difference between the squares of these masses).

Taken from http://t2k-experiment.org/t2k/

Bit Preservation: 

Near Detector:

We have at least three copies of the raw data files.

We usually keep processed data and MC files for a while, but eventually remove old data for space reasons. High level analysis files have all been kept up to now.


We have not thought much about data preservation since ICRR/Kamioka is the host lab, they are actively maintaining the raw data.


Near Detector

Raw data is in MIDAS format. Format is fairly simple, but need MIDAS or ND280 software to read it.

Processed data and MC files are in ROOT format.


Near Detector

MIDAS, ND280 and/or ROOT software needed. virtualization would be helpful, but we have not worked much on this yet.


There is a serious issue with obsolete CERNLIB formats (hbook, ZBS) that is at the core of the Super-K framework, though limited parts of the code are now ROOT-based. There has been a process ongoing for a while to update the code to be at least gfortran-compa2ble so that it can run on modern compilers that we find on ComputeCanada.


The T2K collaboration


Long term archival has not received much attention.


Obsolete CERNLIB formats (hbook, ZBS) are at the core of the SuperK framework.


Ongoing effort to make the SuperK code compatible wiht gfortran.

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