Measurement of the Isolated Prompt Photon Production Cross Section inppCollisions ats=7TeV

The differential cross section for the inclusive production of isolated prompt photons has been measured as a function of the photon transverse energy $E_T^{\gamma }$ in $pp$ collisions at $\sqrt{s}=7\mathrm{TeV}$ using data recorded by the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of $2.9{\mathrm{pb}}^{-1}$. Photons are required to have a pseudorapidity $|{\eta }^{\gamma }|<1.45$ and $E_T^{\gamma }>21\mathrm{GeV}$, covering the kinematic region $0.006<x_T<0.086$. The measured cross section is found to be in agreement with next-to-leading-order perturbative QCD calculations.