Sheila & Dan

We marked the two IM4_TRANS beams (PRM_REFL and IO_TRANS) on the wall of the LVEA today.

To be clear: both of these beams are transmitted through IM4.  One is from the beam leaving the IMC, the other is the reflection coming back from the PRM.  The IO_TRANS beam is in the -X direction on the wall.

We noticed that there are also two green beams very close to the IR beam reflected off the PRM.  Only the Y-arm was locked at the time, so this must be the faint green reflection off of PR2 from the Y-arm.  We might want to use these as a reference for the BS alignment in the future.