Do photons really have a gravitational field like matter?

[Zman]

Because of the mass equivalence of energy, photons are said to have a gravitational field just like matter.

Have there been any experiments to verify that photons have a gravitational field?

 

[jtbell]

A similar question is currently being discussed in the following thread:

https://www.physicsforums.com/showthread.php?t=337857