Good things come to those who wait. But now that the Large Hadron Collider has restarted after undergoing more than a year of repairs, physicists are racing to analyse the data. Just days after the first protons were smashed together at the LHC, the first paper on the results has been accepted to a journal.

The first collisions took place on Monday, 23 November; by Saturday, a paper had been uploaded to the arxiv server, where physicists often publish their results prior to formal publication. Three days later, it had been accepted by European Physical Journal C.

The paper came from researchers working on ALICE, one of six experiments at the world’s most muscular particle smasher, which is located near Geneva, Switzerland.

“It’s probably a record,” says David Evans of the University of Birmingham, leader of the UK contingent at ALICE. “Of course, it had a lot to do with the kudos of being first.”


The speediness was only possible because the collaboration had approved the text of the paper in advance, leaving just a few gaps to fill in once the number-crunchers had analysed 284 of the first ALICE collisions.

The published result is a long way from evidence for the Higgs boson, or proof of the existence of supersymmetry, or hidden dimensions. It is a measurement of a quantity known as pseudorapidity – “basically a posh way of counting charged particles”, says Evans.

Nevertheless, it will be useful. The measurements agree both with theory and results gleaned from other accelerators at similar energies. Evans says that gives the researchers confidence that their detector is working well as the LHC is ramped up to uncharted higher energies.

Journal reference: European Journal of Physics (forthcoming)