# Presentation: 363183

## STAR 62 GeV CuCu Event totals (as of 3/16/05, noon )

- STAR 62 GeV CuCu Event totals (as of 3/16/05, noon )

-  Total: 12.830 Mevts of BBC Narrow
-  Goal > 20 Mevts.
-  BBC Narrow Trigger has been operational for 6 full days. The “run” average number of mb events per day is ~ 1.9 Mevts/day (N.B. Evts taken today not included).

- Ave/day ~ 1.9 Mevts

## STAR 62 GeV CuCu Event totals (as of 3/16/05, noon )

- STAR 62 GeV CuCu Event totals (as of 3/16/05, noon )

-  Total: 11.618 Mevts of ZDC Narrow
-  Goal > 20 Mevts.
-  ZDC Narrow Trigger has been operational for 5 full days. The “run” average number of ZDC events per day is ~ 2.04 Mevts/day (N.B. Evts taken today not included).

- Ave/day ~ 2.04 Mevts

## DAQ Hours

- 62 GeV CuCu DAQ Hours

**DAQ Hours**
- Total 3/10 through 3/15 (6 days) = 56.06 hrs
- <DAQ hrs/day> ~ 9.3 hrs/day
*N.B. “DAQ hrs” only count time when production Cu62 Production Configuration is running.*
*N.B. Hours today (partial 7th day) not included in numbers above.*

## 22 GeV CuCu Development

- Overall Environment (Large backgrounds)

- BBC Coin.
- ZDC Coin.
- BCC Yellow back.
- BBC Blue back.

- ZDC East
- ZDC West
- ZDC Coin.

- BBC Coin.
- ZDC Coin.
- BCC Yellow back.
- BBC Blue back.

- Typical 62 GeV Backgrounds

## 22 GeV CuCu Development

- Vertex Distributions for Data taken at 4:20 pm.
- The Trigger was zdc-tacs
- (ZDC coin. where each ZDC also has a valid timing signal (additional disc. thres,.))
- Expected to have substantial impact parameter bias, but minimal collision vertex bias.
- Short run with low statistics.
- <Vz> ~ 10.6 cm, rms ~ 80.5 cm
- <Vx> ~ -3 mm, rms ~ 5.7 mm
- <Vy> ~ 1.8 mm, rms ~ 4.7 mm

## 22 GeV CuCu Development

- Vertex Distributions for Data taken from 5:28 to 5:58 pm.
- The Trigger was:
-  zdc       (Just zdc adc coin.)
-  zdc-tacs (Add TAC disc. Thres.)
- bbc-narrow (bbc coin. + timing cut)

- N.B. Though I widened the timing cuts on the bbc (triggers mostly background without cut), the Vz dist. Is biased by this trigger)

- <Vz> ~ 15.1 cm, rms ~ 72.8 cm
- <Vx> ~ -2.7 mm, rms ~ 5.3 mm
- <Vy> ~ 1.9 mm, rms ~ 5.4 mm

## 22 GeV CuCu Development

- Vertex Distributions for Data taken from 4:42 to 4:54 pm.
- The Trigger was:
-  zdc       (Just zdc adc coin.)
-  zdc-tacs (Add TAC disc. Thres.)
- bbc-narrow (bbc coin. + timing cut)

- <Vz> ~ 18.1 cm, rms ~ 70.2 cm
- <Vx> ~ -2.7 mm, rms ~ 5.4 mm
- <Vy> ~ 1.7 mm, rms ~ 5.9 mm

- I changed the bbc timing cut (widened it) between this run and 5:28 pm run.

## Typical 62 GeV CuCu Vertex Distributions

- Vertex Distributions for Data taken Tuesday from 9:00 to 9:20 am.
- Running a mix of Triggers.

- <Vz> ~ 4.4 cm, rms ~ 49 cm
- <Vx> ~ -2.2 mm, rms ~ 3.6 mm
- <Vy> ~ 1.8 mm, rms ~ 3.6 mm

- N.B. This Trigger mix biases the Vz distribution.

## Preliminary Conclusions:

- CTB ADC Sum (Mult.)

- CTB ADC Sum (Mult.)

- BBC - Narrow Triggered evts
- Same evts with ZDC coin. Req.

- Ratio of Red hist. To black hist. above

-  ZDC coin. Has very low efficiency for central CuCu collisions at 22 GeV.
-  Including info. from ZDC triggered data set, the BBC has poor efficiency for peripheral collisions.
- Pictorially (rough idea):
- For Central Events
- Seen by BBC
- Seen by ZDC
- For Peripheral Events