# Presentation: 673872

## Year 2001 Data and Analysis

-  RHIC performance
-  STAR Trigger
-  Recorded Event Statistics
-  Offline Production
-  pp Running
-  Summary/Outlook

- Thomas Ullrich, Nov 30, 2001

## RHIC – Performance 2001 compared to 2000

- _Run 2000_
- s = 130 GeV
- 6  56 bunches
- * ~ 5 m
- L  2·1025 (10% design)

- _Run 2001_
- s = 200 GeV
- 56 bunches
- * ~ 5  3 m
- L  2·1026

- STAR 2000

- ~ 8.5 106 sec

****** **L dt  19  year 2000

- 11/30/2001

## Event Selection – The STAR Trigger in 2001

**Considerably more complex than in 2000:**
- New detectors and components
- TDC in ZDC  estimate of z-vertex [cut |z| < (25) 35 cm]
- SVT noise  ~ 2 MB for empty events  low rates at low Nch
- L3 trigger (rare probes)
- ToF, FTPC, EMC no impact on event selection (almost for EMC)
- Optimization of event selection
- Cope with 31⁄2 orders of multiplicity: UPC (1)  central (5000)
- Maximize “useful” events (in terms of physics analysis)
- Trigger setup depends on rates (e.g. L3 only useful at high intensities)
- Minimize bias: ZDC z-vertex cut (L0), L3, etc.
- Rate studies and tests before implementation of triggers
- _Trigger Board_ (chair Tonko) addresses the technical questions 	              (see http://www.star.bnl.gov/protected/trgboard/index.html)

- 11/30/2001

## STAR Trigger (continued)

- The setup of the trigger was a learning process! The following **trigger sets **(aka trigger group or trigger configurations) were used in Au+Au:

| 15PerCTB 15PerCTBVertex Central centralTopo combinedPedestal Cosmic ctbSum CTBWindow emcPedestal EMCtierTEST hanks hanks_emc L3Central L3Central1200 L3Central1200UPC L3Central600 L3Central600UPC  | pedTest 
laser MediumBias MinBias MinBiasPreVertex MinBiasSvtPulser MinBiasVertex MinBiasVertexCTB100SVT MinBiasVertexSVTTest2 MinBiasVtxCTB75noSVT MinBiasVtxCTB75noSVT33k MinBiasVtxMip15noSVT pedAsPhys 
pedestal 
pedestal-obs-7-24  | physics physics-obs-7-24 productionCentral productionCentral600 
productionCentral1200productionCentralKiller productionCentralNoUPC ProductionMinBias pulser SMDTest SVTRawPulser test testCentral topology trgPed UncalibratedMix |
| --- | --- | --- |

*Trigger set contains ****several**** triggers (trigger mix)*

- 11/30/2001

## STAR Trigger: two examples

_**Trigger Set: productionCentral**_
- hi-mult & ZDC	1102
- hi-mult		1101
- Hadronic central	1100
- TOPO		3001
- TOPO & ZDC	3002
- TOPO Efficiency	3011
- pulserSVT		F101
- Laser		F200

_**Trigger Set: productionMinBias**_
- hi-mult		1101
- UPC minbias	1001
- Hadronic minbias	1000
- pulserSVT		F101
- Laser		F200

- In RED: counted for “physics” stats

- 11/30/2001

## STAR Trigger: Usage in Analysis

- Check and understand the trigger definitions of the type of events you want to study
- Run log browser:  http://online.star.bnl.gov/RunLog2001/
- You might need more than one trigger word to your assemble dataset
- In few cases the trigger word changed meaning
- Do not assume the same trigger word describes the same in all trigger sets
- In few cases the vertex cut and other parameters changed in the same trigger set (same configuration name) – this cannot be detected via the offline trigger info
- Central triggers with L3 are biased
- L3 group has lots of info on this on their web pages, also methods in StEvent
- Dedicated web page: **http://www.star.bnl.gov/STAR/html/all_l/trigger2001/**
- Contains description and details on trigger 2001
- FAQ (describing pitfalls), useful links and more
- Please help adding useful info
- And for the real critical stuff (cross-sections, multiplicity distributions etc) talk to the experts: Hank, Jeff, Tonko, Zhangbu, Falk

- 11/30/2001

## Run 2001: “hadronic central” events

| Trigger Set | Field A (+1) | Field 1⁄2A (+1⁄2) |  Field 1⁄2B (-1⁄2)  | Field B (-1) |
| --- | --- | --- | --- | --- |
| central | 98,569 | 0 | 0 | 1,561 |
| productionCentral | 1,315,474 | 0 | 267,417 | 1,447,612 |
| productionCentral600 | 204,163 | 0 | 0 | 181,921 |
| productionCentral1200 | 63,597 | 0 | 0 | 28,311 |
| Summary | 1,681,803 | 0 | 267,417 | 1,659,405 |

_**Total Sum: 3,608,625 events**_**   **(72% of the initially planned 5·106)
- Used ZDC cut at 10% centrality (720 mbarn)  5 b-1
- RHIC:  L dt (hadronic)  34 b-1  max  24 ·106  events
- _We recorded 15% of all (10%) central collisions delivered by RHIC_
- (consider we run central only half the time and with |z|<35 cm)
- Nov 14 – Nov 24: 		1.3 ·106 events
- Record day 11/23/2001:	211k hadronic central events

- 11/30/2001

## Run 2001: “hadronic minimum bias” events

| Trigger Set | Field A (+1) | Field 1⁄2A (+1⁄2) |  Field 1⁄2B (-1⁄2)  | Field B (-1) |
| --- | --- | --- | --- | --- |
| MinBias
Corrected (0.7  0.2) | 29,244
4,094 | 46,088
6,452 | 84,862
11,880 | 556,260
77,876 |
| MinBiasVertex
Corrected (0.7) | 0
0 | 0
0 | 825,136
577,595 | 1,747,058
1,237,724 |
| productionMinBias | 1,033,580 | 0 | 0 | 1,768,178 |
| Summary | 1,037,674 | 6,452 | 589,475 | 3,083,778 |

_**Total Sum: 4,717,379 events**_**   **(94% of the initially planned 5·106)
- Note: these are useful events, i.e. |z|<35 cm and vertex can be found
- Assume observ  0.94  7.2 b = 6.7 b 	 0.7 b-1
- RHIC:  L dt (hadronic)  34 b-1  max  227 ·106  events
- _We recorded 2% of all ‘observable’ hadronic interactions delivered by RHIC_
- (observable means: vertex can be found offline but no |z| range)
- .... 0.5 ·106 min bias events with zero field  and ?? usable events from 19.6 GeV run

- 11/30/2001

## Run 2001: Things to keep in mind

- Lots of important info is not in the run log (sparse comments)
- Volunteers needed: log book  run log
- Detectors in data stream
- TPC – always
- RICH – always
- FTPC – mostly
- pToF – mostly
- SVT – with interruptions
- EMC – only towards the end
- SMD – no
- FPD – rarely
- Detector hiccups
- TPC:
-  # of dead channels varies in time (RDO boards)
- FTPC
- sometimes only FTPC-West
- sometimes with missing sector in FTPC-East
- SVT
- see Rene’s talk earlier
- EMC
- see Alex’s talk earlier

- 11/30/2001

## Example: Bad Sectors

- 230 < day < 253   RDO 21-3 bad
- 254 < day < 266   RDO 9-3 and 21-3 bad
- 266 < day             RDO 9-3 bad

- Run 2266012

**Art Poskanzer**

- 11/30/2001

## Fast Offline

**Purpose:** complete reconstruction of parts of the recorded events processed in a timely fashion (hours) for QA
- Setup, maintained, petted, and cursed by Jerome
- Use 7 nodes (14 CPUs) out of 124 CRS nodes
- Use up to 60% of reserved 1 TB disk (purged frequently)
- Of 12 · 106 recorded events, 11% processed over the entire time
- Not always timely (days) depending on RCF
- Long term: use online cluster sitting in DAQ-room
- Fast Offline runs with the “dev” version
- Latest status but also with the most recent bug

- Please Note: results from fast offline are NOT publishable
- (no stable chain, bugs in chain, calibration pass not reliable)

- 11/30/2001

## Offline Test Runs

- Short (test) productions as requested by detector subgroups via period-coordinators or SAC (e.g. for ToF, L3, EMC, FTPC, calibration studies, 19.6 GeV run)
- Managed by Lidia and Jerome
- Competes with “standard” production on 117 (of 124) CRS nodes
- So far ~ 2M events processed
- Sometimes run in “dev”, sometimes in “pro” depending on needs

- Parts of Jerome’s TODO List

- Please Note: results from offline test runs are NOT publishable
- (no stable chain, bugs in chain, calibration pass not reliable)

- 11/30/2001

## Year 2001 Au+Au Reconstruction

- Current ‘official’ production version is P01gk
- Original plan: produce only parts and have people check data quality
- Reconstruction of TPC, RICH, L3 only (ToF raw data on DST)
- So far: ~ 106 events minimum bias
- Up to now no requests from PWGs for more ...
- Next round:
- might be **the** one for QM2001 in Nantes
- aim for complete production (i.e. all y2001 data)
- include FTPC (at least let’s try hard)
- require RICH to provide PID which can be used directly by any user (StRichPidTraits)
- possibly new corrections for TPC (see Jamies talk)
- might be the last big production before ITTF comes in (see Mikes talk)
- We need to fix TRS (“loving owner” issue)  a.s.a.p
- Still problems with disks at RCF, need solution soon
- ITTF evaluation will need some resources
- Near future: need coordination of **all** slow simulators (simulation leader)

- 11/30/2001

## Preparation for pp Analysis 

- So far:
- Reconstruction  optimized for heavy-ions making use of:
- very precise vertex
- lots of tracks/event for calibration
- pp spin program focus on the lower end in Nch
-  worse vertex resolution
- many small events (I/O vs CPU)
- need to keep track of polarization
- handling pile-up events
- new trigger configurations

- _pp software workshop on 11/19_** **
- Event vertex resolution
- ppLMV has a sigma of about 2 cm for x,y,z
- Need  to do much better (new code, EVR?)
- How stable is beam spot in x,y ?
- pp-production chain needs to be finalized
- Currently big memory leaks that kill the jobs after ~200 events
- Trigger info.
- trigger scalers info in Db, work in progress
- Drift velocity calibration
- Present algorithm is not useful for pp
- rely more on laser runs
- All minutes and some (important) slides posted on reco pages:
- http://www.star.bnl.gov/STARAFS/comp/reco/

- 11/30/2001

## Summary and Outlook

- We have plenty of data on tape
- min bias: 	y2001  10  y2000
- central:	y2001  7  y2000
- Reach new physics
- High-pt
- h spectra and anisotropy out to 12 GeV/c,  (?), ratios at high-pt (RICH)
- Strangeness
- ,  (width, mass-shifts), higher reach in pT for (multi-) strange baryons, (1520), K*(1430), (1385)
- HBT
- 3D K-K, K- w/ greater resolution, K-p, -p, K0s-K0s, pt dependence of R()
- Spectra
- , ****He4, particle ration
- EbyE
- , K* flow, K/
- ... and much more ...

- Lots of work to do to get analysis chain fully functional
- Need more help on:
- TRS
- Embedding production
- Code development and maintenance
- pp chain
- First steps for analysis:
- normalized multiplicity distribution
- Define common multiplicity classes
- Future
- ITTF
- Reshape chain (tables -> StEvent)
- DAQ100

- 11/30/2001