Preshower Tile Test, February 2014
February 26, 2014
This is the first day we try to run the test in the new lab space (also see this pic).
Mostly tried to reproduced the earlier result on the LHCb tile. Had to
change the PMT HV (increase by 200V), replaced a PMT, etc. But at the
end got nearly 22 ph.e. for MIP.
February 27, 2014
First try on the Chinese hexagon tile. For comparison:
- 1.5cm thick or 18/32", 12x12cm^2 square;
- fiber (Y11) embedded 3.5 turns (nearly 4 turns if including the straight portion);
- fiber length about 30cm on either side (see December 2013 record and picture)
- single p.e. peak around 26; MIP peak around 541; see russ_tile_20140227_3.5turns.pdf or PNG
- Chinese tile:
- 2cm thick or 24/32", 6.25-cm side hexagon;
- We
inserted a 3-m long Y11 fiber, embedded 2.3 turns (the 3rd turn keeps
popping out, only partially in the tile). The fiber sticked out pretty
long before the PMT end (at least 1m more decay length compare to LHCb
tile).
- single p.e. peak around 27;
- Based
on LHCb tile response we expected the Chinese tile MIP peak to be at:
24/18*2.3/3.5*27/26*541=492 +/- 20 given the error on determining the
s.p.e. peak.
- We measure 497 for the four hour run 1228, see Chinese-tile-20140227-4hour_2turns.pdf or PNG
- An overnight run gave slightly lower MIP response, could be because part of the fiber popped out, see pictures: pic1 pic2 pic3; MIP response: chinese-tile-20140227overnight_2turns.pdf or PNG
February 28, 2014
Test Chinese tile:
- reduced fiber to single turns. See pictures: pic1 pic2 pic3;
- MIP response: chin_tile_20140228_singleturn.pdf or PNG; Single p.e. at about ch25. Number of p.e. about 8.5 which is what we expected if it is linear with fiber length embedded.
Summary and Next step:
- Confirmed 22 p.e./MIP for LHCb tile. Chinese tile
performance comparable to LHCb tile. Number of p.e. linear to fiber
turns inside the tile.
- Will setup COMPASS module, vertically but will be tilted (dark box not tall enough), test MIP response;
- Wait for BCF92 fiber and IHEP tiles to come in, test more turns;
- Order fiber connectors and study loss;
