Abstract
We compute the next-to-next-to-leading order QCD corrections to the graviton production in models of TeV-scale gravity, within the soft-virtual approximation. For the Arkani-Hamed, Dimopoulos and Dvali (ADD) model we evaluate the contribution to the Drell-Yan cross section, and we present distributions for the di-lepton invariant mass at the LHC with a center-of-mass energy $\sqrt{s_H}=14\text{TeV}$. We find a large $K$ factor ($K\simeq 1.8$) for large values of invariant mass, which is the region where the ADD graviton contribution dominates the cross section. The increase in the cross section with respect to the previous order result is larger than $10\%$ in the same invariant mass region. We also observe a substantial reduction in the scale uncertainty. For the Randall-Sundrum (RS) model we computed the total single graviton production cross section at the LHC. We find an increase between $10\%$ and $13\%$ with respect to the next-to-leading order prediction, depending on the model parameters. We provide an analytic expression for the NNLO $K$ factor as a function of the lightest RS graviton mass.
Highlights
For the Randall-Sundrum (RS) model we computed the total single graviton production cross section at the LHC
Real graviton production leads to missing energy signal and a cross section for the production of a single graviton dσmn has to be convoluted with the graviton density of state to get the inclusive cross section
We have calculated the NNLO QCD corrections to the graviton production in models of TeV-scale gravity, working within the soft-virtual approximation, which is known to be very accurate for similar processes
Summary
The spin-2 form factor has been calculated recently by us in ref. [29]. [30] some of us derived a universal formula for the NNLO inclusive cross section of any colourless final state process within the soft-virtual approximation This formula depends on the particular process only through an infrared regulated part of the one and two-loop corrections, which can be obtained from the full virtual result [30] for more details) In this way we can obtain the NNLO corrections to single graviton production and gravity mediated di-lepton production within the soft-virtual approximation. We present below the NNLO results in the soft-virtual approximation Within this approximation we have only contributions to the gluon-gluon and quark-antiquark subprocesses, since the terms proportional to δ(1−z) and Di (which are the ones we obtain within the SV approximation) are absent in other channels. See for example ref. [30]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have