https://doi.org/10.1140/epjc/s10052-017-5449-6
Regular Article - Theoretical Physics
Greybody factor of scalar fields from black strings
1
Department of Mathematics, Quaid-i-Azam University, Islamabad, Pakistan
2
Department of Physics and Astronomy, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
3
Center for the Fundamental Laws of Nature, Harvard University, Cambridge, MA, 02138, USA
* e-mail: ksaifullah@fas.harvard.edu
Received:
21
August
2017
Accepted:
1
December
2017
Published online:
18
December
2017
The greybody factor of massless, uncharged scalar fields is studied in the background of cylindrically symmetric spacetimes, in the low-energy approximation. We discuss two cases. In the first case we derive analytical expression for the absorption probability when the spacetime is kinetically coupled with the Einstein tensor. In the second case we do the analysis in the absence of the coupling constant. For this purpose we analyze the wave equation which is obtained from Klein–Gordon equation. The radial part of the wave equation is solved in the form of the hypergeometric function in the near horizon region, whereas in the far region the solution is of the form of Bessel’s function. Finally, considering continuity of the wave function we smoothly match the two solutions in the low-energy approximation to get the formula for the absorption probability.
© The Author(s), 2017