T0 offline status
Alla Maevskaya
for T0 team
ALICE offline week
6 July 2010
Outline

What was new in T0 code
Reconstruction
 LHC10b
 LHC10c
 recent runs reconstruction


QA

Calibration
Alla Maevskaya
ALICE offline week 6 July 2010
Some news about T0 code

Move L0/L1 trigger delays from AliRecoParam to OCDB;

Dummy SDigits were implemented;
Parameters of material optical properties defined for T0 did not work
correctly with Geant4, fixed now (thanks to Alexei);


AliESDTZEROfriends were implemented but were not used yet;

AliT0Reconstructor was tuned for current data;

AliT0RawReader collects bunch ID from TRM header.
Alla Maevskaya
ALICE offline week 6 July 2010
Physics runs April 2010
During the April 2010 data taking:
ELMB switched off (not possible to
change the thresholds and walk time for
CFDs)
Laser did not work so we could not
prepare time-amplitude calibrations
But:
Early fired
peak
Only events with LED-CFD
amplitude > 540 were reconstructed
Alla Maevskaya
ALICE offline week 6 July 2010
LHC10b Pass2, run 115318
(T0A+T0C)/2
T0C
Alla Maevskaya
T0A
(T0A-T0C)/2
coorected by
SPD vertex
ALICE offline week 6 July 2010
LHC10b Pass2 run 115318
vertex resolution
SPDvertex(Ncontributers>1)
T0 vertex
T0vertex in events without SPD vertex
Alla Maevskaya
SPDvertex – T0vertex
ALICE offline week 6 July 2010
LHC10b : T0 resolution and
efficiency
CINT1BCINT1BCINT1BABCE-NOPF- ABCE-NOPF- ABCE-NOPFALL
ALL
ALL
SPD vertex
with >1
contributres
Alla Maevskaya
T0 – A
62%
76%
T0 – C
59%
72%
T0 – OR
80%
99%
T0 – AND
41%
50%
ALICE offline week 6 July 2010
May10 - LHC10c
From May 2010 data taking:
ELMB switched on (new thresholds & walk times for CFDs)
Time-amplitude correction
graph prepared by
Laser Calibration System
Alla Maevskaya
ALICE offline week 6 July 2010
CDH and T0 bunch ID
Single_6b_3_3_3
Run 120244
Alla Maevskaya
Good
correlation
Single_13b_8_8_8
Run 120824
ALICE offline week 6 July 2010
Problems with LHC10c runs:
no correlation with SPD in the filling schemes
Single_6b_3_3_3 and Single 13b_8_8_8
Only events with TRM BC ID CDH BC ID ==37 (diagonal )
were chosen for reconstruction
Run 120244
Single_6b_3_3_3
Single 13b_8_8_8
run 120824
T0 vertex and SPD vertex
T0 vertex – SPD vertex
Alla Maevskaya
ALICE offline week 6 July 2010
Recent runs with filling scheme
Single_7b_4_4_4 run 125078 5 July
alien:///alice/data/2010/LHC10d/000125078/raw/10000125078045.10.root
alien:///alice/data/2010/LHC10d/000125078/raw/10000125078045.20.root
Alla Maevskaya
ALICE offline week 6 July 2010
Recent runs with filling scheme
Single_7b_4_4_4 run 125078
alien:///alice/data/2010/LHC10d/000125078/raw/10000125078046.10.root
alien:///alice/data/2010/LHC10d/000125078/raw/10000125078046.20.root
alien:///alice/data/2010/LHC10d/000125078/raw/10000125078043.10.root
alien:///alice/data/2010/LHC10d/000125078/raw/10000125078043.20.root
Alla Maevskaya
ALICE offline week 6 July 2010
Good runs from T0 point of view
LHC10b and LHC10c
All LHC10b
with both filling scheme Single_2b_1_1_1 and Single_3b_2_2_2
LHC10c
- 900Gev runs
7TeV:
118903 – 119163 filling scheme Single_2b_1_1_1

Bad runs:
 119837 – 119862 due to TRM problem
Problem runs:
all runs 120064-end of LHC10c – filling schemes Single_6b_3_3_3
and Single_13b_8_8_8 without correlation with SPD vertex

Alla Maevskaya
ALICE offline week 6 July 2010
13
Changes in T0 reconstruction
AliT0RawReader , storing TRM BC ID
AliT0Reconstructor:
only events with TRM BC ID – CDH BC ID ==37
(magic number, should be read from
AliT0RecoParam) are to be reconstructed;
time-amplitude calibration by QTC amplitude will be
used only for LCH10d (and later on) data
Alla Maevskaya
ALICE offline week 6 July 2010
QA: DQM shifter histograms
During data taking laser calibration with given
amplitude will take place in big gaps between
bunches to check PMT and electronics
Alla Maevskaya
ALICE offline week 6 July 2010
QA RAW
Coming soon
for us to be published
in logbook
for DQM shifter
Alla Maevskaya
ALICE offline week 6 July 2010
Calibration
DA T0Physda is running on T0 DAQ machine during physics
runs. It collects time shifts between channels and T0 time for
control clock shift.
DA T0Laserda running during set of runs
“AMPLITUDE_CALIBRATION” and produces data for timeamplitude calibration.
But mostly data was not smooth and handmade treatment
needed.
I hope to solve this as soon as possible
Alla Maevskaya
ALICE offline week 6 July 2010
Do be done
Get online calibration data automatically
Implement pass0 calibration as AnalysisTask to run after
reconstruction
New set of DQM histograms
AliT0Checker should be improved and colored in “MUON” style
New OCDB object should be added
New parameters should be added in AliT0RecoParam
Alla Maevskaya
ALICE offline week 6 July 2010
Back up slides
Run 120824
Single_13_8_8_8
Chunk 45
Chunk 57
Chunk 56
Chunk 58
Run 120244 Single_6b_3_3_3
Chunk 43
Chunk 45
Run 125078 5 July Single_7b_4_4_4
10000125078045
10000125078046
10000125078043.20
10000125078044