Off-line and Detector Database

Kopenhagen TPC meeting A.Sandoval

AliRoot 3.08 Rev1• Reference volumes defined for all detectors. For all

tracks the entry and exit point and the track parameters are stored in special tree.

• For the TPC these are the parallelepipeds defined by the readout chambers.

• TPC track reconstruction has been parameterized at the entrance of the TPC for , K, p, e in bins of pt, , by Andrea Dainese and Rosario Vicen used for fast simulations

• prepared but not committed to CVS:– PID from dE/dx by Boris Batunjia– multiple seeding for the Kalman filter by Sylwester

Radomski

PPR production with Aliroot 3.08R1

• 100’000 pp events at 14 TeV using Pythia

• 5’000 min bias Pb+Pb Hijing

• 500 central Pb+Pb Hijing

• wainting central Pb+Pb with jets (Hijing standard with Hijing jets)

Open Questions in TPC tracking

• Parallel Kalman tracking (Marian Ivanov) together with cluster finder. Needs very good seeds with no fakes

• Cluster deconvolution for 2, 3 or more track overlaps

• Non vertex tracks

• Take Bremsstrahlung of electrons into account

TPC seeding meeting in Bergen

Bring together the online (HLT) and offline TPC tracking

Dieter, Anders Vestbo, Thomas Vik, Konstantin Loizidis, Yiota, Sylwester Radomski, Marian Ivanov, Ajit Kumar,AS

• Take the global track finding from HLT using Hough transform as seeds for the Kalman tracking (Anders, Kostantin, Sylwester)

• Do intelligent cluster deconvolution by fitting multiple-2 dimensional Gaussians knowing the track parameters from Hough tracking and then apply Kalman tracking (Anders, Marian)

Thursday-Saturday last week

• Try out combinatorial tracking (maximal entropy) not on clusters but on matchsticks obtained from linear Hough transform on small overlapping patches (Dieter, Anders, Ajit, Karel)

Databases

• The infrastructure to create an Alice detector database has been provided by the Warsaw group.– Central database at CERN, satellite databases where

needed for each Detector– the tables (dictionaries) are created by the detector

groups for Components (Sub-components|) and Processes applied to this components

Observations

• To create a detector database that is useful in the lifetime of ALICE we have to do a good top-down Detector partitioning and create all the necessary relations between parts– one has to be able to look at the data from different

points of view.– we have to decide if functionally we need only one

TPC satellite database in GSI or several at different institutes