‘Big Bang’ particle collider restarts after refit

A scientist at the Large Hadron Collider. Particles travel round the circuit significantly faster Keystone

Scientists at the European Organization for Nuclear Research (CERN) have restarted their Large Hadron Collider (LHC) “Big Bang” machine after a two-year refit, launching a new bid to resolve some of the mysteries of the universe. 

In a live blogExternal link covering the restart, CERN said on Sunday that one of the two beams had completed the 27km circuit of the LHC, beneath the Swiss-French border near Geneva. 

The LHC had been shut down for two years for a refit of its machinery and wiring. CERN spent about $150 million (CHF144 million) on the upgrade, opening the massive machine every 20 metres, checking magnets and improving connections. 

Any new discoveries it makes are unlikely to emerge until mid-2016. Scientists are promising nearly twice the energy and more violent particle crashes this time around. They hope the more powerful beam crashes – expected to start as early as June – will give them a peek into the unseen dark universe. 

The collider was instrumental in the discovery of the Higgs boson, a subatomic particle that had long been theorised but never confirmed until 2013.