Greybody factor and sparsity of Hawking radiation from a charged spherical black hole with scalar hair

Understand

The `no-hair' conjecture claims that for a spherically symmetric black hole, only the information regarding the mass and charge of the black hole is available to an external observer.

• However, there are numerous counterexamples to the `no-hair' conjecture.
• In this work, we consider a particular counter-example to the `no-hair' conjecture in (3+1) dimensions, namely, a static spherically symmetric charged black hole with a scalar hair.
• We provide semi-analytic bounds on the greybody factors and study the sparsity of Hawking radiation of mass-less uncharged scalar fields.