[Stuart A, Travis S]

A request was made from Matt H and Jeff K to provide the distribution of addable mass used on the LHO PR3 (HLTS) suspension. Unfortunately, in this instance the paper-trail (and ICS trail) quickly ran cold. The distributions had been captured for subsequent suspensions, just not unfortunately for the first assembled PR3.

It was therefore necessary to conduct a visual inspection, and with the assistance of Travis, we were able to determine the following:-

M1 addable mass:-
M1 (upper) = 100+100+20+10 = 230g (+ nut)
M1 (lower) = 100+100+20+10 = 230g (+ nut)

M1 sliding masses:-
M1 roll adjustment, protruding ~11-12mm towards LF side
M1 pitch adjustment, ~centred

M2 addable masses:-
LF (front) = 100+20 = 120g, RT (front) = 20g (refer to pictures for fixing screws & nut arrangements)
LF (back) = 0g, RT (back) = 100+20 = 120g (refer to pictures for fixing screws & nut arrangements)

M2 sliding masses:-
M2 pitch adjustment, protruding ~2mm towards back

Many pictures have been taken during this inspection of PR3, a choice selection of which can be found attached below.

Image 836, PR3 storage barrel re-located to a chamber-side clean-room.
Image 866, Storage barrel lifted and removed, revealing PR3.
Image 851, M1 and M2 masses taken from front of suspension.
Image 857, Close-up of M2 taken from front of suspension.
Image 862, Close-up of M2 taken from back of suspension.

N.b. naming convention used is consistent with M1 stage BOSEMs, which are fitted to back of the suspension.