Rotating black holes at future colliders: Greybody factors for brane fields

We study theoretical aspects of rotating black hole production and evaporation in extra dimension scenarios with TeV scale gravity, within the mass range in which the higher dimensional Kerr solution provides a good description. We evaluate the production cross section of black holes, taking their angular momenta into account. We find that it becomes larger than the Schwarzschild radius squared, which is conventionally utilized in the literature, and our result nicely agrees with the recent numerical study by Yoshino and Nambu within a few percent error for the higher dimensional case. In the same approximation used to obtain the above result, we find that the production cross section becomes larger for a black hole with larger angular momentum. Second, we derive the generalized Teukolsky equation for spin 0, 1/2, and 1 brane fields in higher dimensional Kerr geometry and explicitly show that it is separable in any dimensions. For a five-dimensional (Randall-Sundrum) black hole, we obtain analytic formulas for the greybody factors in the low frequency expansion and we present the power spectra of the Hawking radiation as well as their angular dependence. The phenomenological implications of our results are briefly sketched.