SA crunches into the collider data grid
South Africa has joined the computing grid for the largest particle accelerator in the world, the Large Hadron Collider (LHC).
The collider, which straddles the border between France and Switzerland and is about 100m underground, is a massive particle accelerator, owned by the European Organisation for Nuclear Research (Cern).
The super-conducting magnets in the accelerator propel two beams of particles – protons or lead atoms – around the 27km ring and smash them into each other in a bid to understand the particles that constitute matter by sifting through the microscopic debris.
South Africa was not officially part of the grid but has been involved in LHC experiments for a number of years through the iThemba Laboratory for Accelerator-Based Sciences and the universities of Johannesburg, Witwatersrand, KwaZulu-Natal and Cape Town.
On Tuesday, the collider smashed its first particles in two years, after having been closed for maintenance. Its future collisions will be at increasingly higher energies, pushing the boundaries of particle physics.
South Africa and Cern have been collaborating for more than two decades, but the country’s admittance into the computing grid marks a milestone in the partnership, says Jean Cleymans, chairperson of the SA-Cern programme.
“They’ve unofficially been part of it for two years, but now there will be recognition for it and scrutiny if there are problems,” he told the Mail & Guardian.
The collider produces huge quantities of data and this computing grid, with facilities at 175 sites in 35 countries and about 250 000 computing cores, processes this data.
South Africa will be joining as a tier two facility, based at the Centre for High Performance Computing in Cape Town. There are four tiers, with tier zero being the main data crunching hubs. One is at Cern and the other in Hungary. Tier three involves the access of local computer resources.
South Africa is now one of 155 tier two sites in the world.
Dr Happy Sithole, director of the centre, says: “The facility is providing the infrastructure for the tier two facility … the computing, the connectivity, the support … [For the last two years] on a trial basis, we’ve been giving the support. [Cern] doesn’t accept a new partner [to the computing grid] immediately, unless it has demonstrated that it can provide the support.”
The big question, though, is how bandwidth-thirsty South Africa can offer a service that requires fast connectivity. Sithole says the department of science and technology has bought bandwidth on the West Africa Cable System (Wacs) “specifically to support international projects”. At the moment, the centre is using Seacom to service Cern, but is moving to Wacs after June.
Cern’s benefits include the additional computing power to cope with the data that will increase as the particle beams are operated at higher energies.
“The next run [of the collider] will be at a higher intensity, higher energy, so everything will be a little bit better, producing more data. They really need [the extra processing capacity],” Cleymans says.
“It helps Cern, but it also gives the local HPC [high-performance computing] community access, not only to Cern, but to all the other groups [making] it easier for training people. We can send them there. It’s easier to attend workshops, schools, training facilities.”
Sithole says South Africa’s involvement will also show the world that the country has the ability to support international science experiments, such as the Square Kilometre Array.
The SKA will be the largest radio telescope in the world, with its core based in the Northern Cape and, like the collider, will also be a big data project. The SKA will generate in the order of 14 exabytes (equivalent to 14-billion 1GB iPods) a day. “It also gives us an opportunity to learn how to provide optimal support for such large projects,” Sithole says.