V. Altini, T. Anticic, F. Carena, W. Carena, S. Chapeland, V. Chibante Barroso, F. Costa, E. Dénes, R. Divià, U. Fuchs, I. Makhlyueva, F. Roukoutakis,

V. Altini, T. Anticic, F. Carena, W. Carena, S. Chapeland, V. Chibante Barroso, F. Costa, E. Dénes, R. Divià, U. Fuchs,

I. Makhlyueva, F. Roukoutakis, K. Schossmaier, C. Soós, T. Kiss, P. Vande Vyvre, B. von Haller

For the ALICE Collaboration

CHEP - Prague March 2009

Commissioning and initial experience with

the ALICE on-line

Commissioning and initial experience with

the ALICE on-line

CHEP March 2009 2

Outline

•ALICE experiment

•ALICE online systems

•Detector Commissioning

•Global Commissioning

•Lessons from 2008

•Goals for 2009

•Conclusion

P. VANDE VYVRE CERN-PH

CHEP March 2009 3

ALICE @ LHC Point 2


ALICE ALICE

CERN CH CERN CH

CHEP March 2009 4

ALICE: A Large Ion Collider Experiment at CERN-LHC

•General-purpose heavy-ion detector•Study of strongly interacting matter and the quark-gluon plasma in

nucleus-nucleus collisions at the LHC

•Detector designed to cope with the highest particle multiplicities anticipated for Pb-Pb reactions

•Complex experiment for online systems•18 detectors (last one being installed now)

•10 detectors providing input to the trigger

•2 types of beams: pp and Pb-Pb

•3-level hardware trigger and 1 High-Level Trigger firmware/software

•Multiple partitions and multiple detector clusters

•Not surprisingly: complex commissioning !


CHEP March 2009 5 P. VANDE VYVRE CERN-PH

Size: 16 x 26 metersWeight: 10,000 tonnes

18 detectors5 online systems

ALICE

CHEP March 2009 6

Trigger – DAQ – HLT ‘08


GDC TDSM

CTP

LTU

TTC

FERO FERO

LTU

TTC

FERO FERO

LDCLDC

BUSY BUSY

Rare/All

Event Fragment

Sub-event

Event

File

Storage NetworkPDS

L0, L1a, L2

L0, L1a, L2

360 DDLs

D-RORCD-RORC

EDM

LDC

D-RORC D-RORC

Load Bal. LDC LDC

D-RORC D-RORC

HLT Farm

FEPFEP

DDL

H-RORC

10 DDLs

10 D-RORC

10 HLT LDC

120 DDLs

DADQM

DSS

Event Building Network

430 D-RORC

125 Detector LDC

30 GDC10 TDSM

18 DSS20 DA/DQM

25 TDS

Archiving on Tapein the ComputingCentre (Meyrin)

CHEP March 2009 7

Trigger – DAQ – HLT ‘09


GDC TDSM

CTP

LTU

TTC

FERO FERO

LTU

TTC

FERO FERO

LDCLDC

BUSY BUSY

Rare/All

Event Fragment

Sub-event

Event

File

Storage NetworkPDS

L0, L1a, L2

L0, L1a, L2

360 DDLs

D-RORCD-RORC

EDM

LDC

D-RORC D-RORC

Load Bal. LDC LDC

D-RORC D-RORC

HLT Farm

FEPFEP

DDL

H-RORC

10 DDLs

10 D-RORC

10 HLT LDC

120 DDLs

DADQM

DSS

Event Building Network

430 D-RORC

125 Detector LDC

90 GDC30 TDSM

18 DSS40 DA/DQM

75 TDS

Archiving on Tapein the ComputingCentre (Meyrin)

CHEP March 2009 8

Control Logical Model


DAQ

ECS

CTPDCS HLT

ECS: Experiment Control SystemDCS: Detector Control SystemCTP: Central Trigger ProcessorDAQ: Data AcquisitionHLT: High Level Trigger

CHEP March 2009 9

Detector in Standalone Mode


DAQRun Control

TPC

ECSDCA

LTUTPC Control

DCSTPC

LVGasHVTPCLTU

LDC1

LDC 2

LDC216

HLT

Farm

DCA: Detector Control AgentLTU: Local Trigger Unit

CHEP March 2009 10

Global Partition


DAQTPC

DCATPC

LTUTPC

DCSTPC

HLT

DCA: ECS Detector Control Agent PCA: ECS Partition Control Agent

DAQSPD

DCASPD

LTUSPD

DCSSPD

HLT

DAQMuon

DCAMuon

LTUMuon

DCSMuon

HLT

PCASPD


Data Quality Monitoring

DQM framework is ready.Not yet used routinely by all detectors.


eLogBook

Electronics Logbook

Online status displayof TRG and DAQ running conditions

Run statistics with filter on all fields

eLogBook:From replacing the paper logbook to a powerfulldata mining tool

CHEP March 2009 13

ALICE Commissioning 2007-09


Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar2007 2008

1st global run

10-21 Dec

2nd global run

4 Feb-9 Mar

3rd global run

5 May – 20 Oct

First particles from

machine 15 Jun

Injection tests

8 Aug, 24 Aug

1st Circulating

beam

10 Sep

Installation & Commissioning24/7 operation

20092008

Installation&Upgrade

Helium leak

incident

19 Sep

CHEP March 2009 14

Detector Commissioning

•Standalone commissioning•Services: cabling, cooling, power supplies, etc

•Detector hardware, firmware, software

• Interfaces to online systems

•Online commissioning process•Control procedure up to the state “Ready for Data Taking”

•Exposed to variety of trigger (cosmic, pulser up to 40 MHz, random)

•Data taking stability tests

•Calibration procedure

• Integration to global partition


CHEP March 2009 15

Detector Commissioning


ACOFM

DM

TGPHO

SDDSSD

TOF

TRD V01

10

100

1,000

Time (hours) of the standalone runs per detector Dec '07

Feb-Mar '08

May-Oct '08

CHEP March 2009 16

Global Commissioning

•Exercise stability•Detectors

•Services

•Online systems

•23 systems (18 detectors and 5 online systems) 0.97 23 < 0.5 !

•Measure performance•Detector readout time and event size

•Online systems

•Take data•Cosmic data for detector alignment

•Detector calibration (E.g.: TPC calibration with krypton or laser)

•Organize operation


CHEP March 2009 17

ALICE Control Room


Day…

and night

CHEP March 2009 18

Cosmic Run I (Dec ‘07)


Global runs in 2 weeks14 detectors participating

10-60 hours of data taking – 1-20 x 106 triggers

CHEP March 2009 19

Cosmic Run I

•TOF•Comparison of hit time

distribution in ACORDE and random triggers

•SPD•Comparison of number of

clusters per event in the 2 SPD layers


CHEP March 2009 20

Cosmic Run II (Feb-Mar ‘08)




CHEP March 2009 21

Cosmic Run II•TPC

•Cluster distribution•Resolution over drift length

•Muon Tracking•Online data monitoring vs offline analysis


CHEP March 2009 22

Cosmic Run III (May-Oct ‘08)




CHEP March 2009 23

Cosmic Run III


after alignment

before alignment

SSD: p-n charge correlation

SDD: Drift speed calibration vs

position

SPD Alignment:

CHEP March 2009 24

Global runs


2 3 4 5 6 7 8 9 10 11 121

10

100

1,000

Time (hours) of global runs as a function of the number of detectors

Dec '07

Feb-Mar '08

May-Oct '08

Global runs with all detectors are still difficult to achieve

CHEP March 2009 25

System Stability


60 10 5 2 00%

20%

40%

60%

80%

100%

120%

Fraction of subevents as a function of minimum run duration

Dec '07

Feb-Mar '08

May-Oct '08

Stability of global runs has improved substantially during the cosmic runs

CHEP March 2009 26

ALICE SPD: the first LHC “event”


On 15 June 2008 the ALICE SPD in self-triggering mode (L0) sees one of the first “sign of life” of LHC during the beam injection

test in Tl2

Run 38795Time 18:10

CHEP March 2009 27

Lessons from 2008

•Services•Detectors:

•Work in progress for firmware and software readout time and zero suppression (event size)

•Noise and grounding

•Online systems:•Control scalability: some systems isolated and load distributed•CPU needed for data formatting: late decision to format data into

reconstruction ready format CPU needed higher than anticipatedPrice to pay for allowing single pass offline analysis

•Spurious triggers : fixed during cosmic run•Global sequences of detector control still in the phase of being

defined Not yet fully automated

•But a successful commissioning of the whole experiment and ready for startup in September ‘08


CHEP March 2009 28

Goals for 2009… and after

•Ready for a nominal data taking year 10 months pp + 1 month HI

•Full deployment of the DAQ system: 40 100 % performance• Increase of HLT CPU power

• Improve feedback to shift crew (DQM deployment)•Reduce the size of shift crews

•Group of detectors•Automation of atomic operations (configuration, calibration)•Automation of global planning

•Central system for the configuration/archiving of all the trigger detectors and the corresponding trigger processors


CHEP March 2009 29

Conclusion

•ALICE became reality after almost 15 years of design

and installation

•Commissioning of detectors and online systems lasted

from Dec ‘07 to Sep ’08. Work intensive !

•Online systems contributed to the detector

commissioning, alignment, and calibration

•Experiment ready to start with beam in September ‘08

•Will be ready again in September ’09 !


Documents

V. Altini, T. Anticic, F. Carena, W. Carena, S. Chapeland, V. Chibante Barroso, F. Costa, E. Dénes, R. Divià, U. Fuchs, I. Makhlyueva, F. Roukoutakis,