Article

A comparative measurement of and in In–In collisions at the CERN SPS

Fuel and Energy Abstracts 05/2011; 699(5):325-329. DOI: 10.1016/j.physletb.2011.04.028
Source: arXiv

ABSTRACT

The NA60 experiment at the CERN SPS has studied $\phi$ meson production in
In-In collisions at 158A GeV via both the $K^+K^-$ and the $\mu^+\mu^-$ decay
channels. The yields and inverse slope parameters of the $m_T$ spectra observed
in the two channels are compatible within errors, different from the large
discrepancies seen in Pb-Pb collisions between the hadronic (NA49) and dimuon
(NA50) decay channels. Possible physics implications are discussed.

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