Upsilon(1S), Upsilon(2S) and Upsilon(3S) cross section measurements in pp collisions at sqrt(s) = 7 TeV

The differential cross section as a function of transverse momentum for the production of the $\Upsilon(nS)$ ($n$=1,2,3) states decaying into a pair of muons has been measured in pp collisions at $\sqrt{s}$ = 7 TeV using 4.9 fb$^{-1}$ of data collected by the CMS detector. The analysis selected events with dimuon rapidity $|y(\mu\mu)|< 0.6$, and the measurements cover dimuon transverse momentum in the range $p_T(\mu\mu)=$10-100 GeV. The data show a transition from exponential to power-law behavior in the neighborhood of 20 GeV, and the power-law exponents for all three states are consistent. The ratio of differential cross sections for higher-$n$ S-wave relative to lower-$n$ S-wave states rises at low $p_T(\mu\mu)$, then becomes flatter at higher $p_T(\mu\mu)$ where the power-law behavior dominates.