Search for narrow resonances lighter than $\Upsilon$ mesons

TL;DR

This paper searches for narrow resonances lighter than the Upsilon mesons in proton-antiproton collisions, setting upper limits on their production relative to the Upsilon(1S) using dimuon mass spectra.

Contribution

It provides the first limits on narrow resonance production in the 6.3 to 9.0 GeV/c^2 mass range at Tevatron energies.

Findings

Set 90% credible upper limits of about 1% on production cross section ratios.

Analyzed 630 pb$^{-1}$ of data from the CDF II detector.

No evidence of narrow resonances was observed.

Abstract

We report a search for narrow resonances, produced in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV, that decay into muon pairs with invariant mass between 6.3 and 9.0 GeV/c^2. The data, collected with the CDF~II detector at the Fermilab Tevatron collider, correspond to an integrated luminosity of 630 pb$^{-1}$. We use the dimuon invariant mass distribution to set 90% upper credible limits of about 1% to the ratio of the production cross section times muonic branching fraction of possible narrow resonances to that of the $\Upsilon(1{\rm S})$ meson.