U.Gasparini 3/04/02 1

Calibrations & monitoring for DT

-Trigger level e.g.: - internal local clock phase adjustment of BTI - absolute syncronization (using the LHC bunch structure) - Track Finder LUT’s calibration

-TDC level - threshold calibration - t0 calibration - gap test/ test-pulse - rate measurement - tmax, vdrift measurement - alignment with muons

For DT chambers, “calibration” is mainly a timing/syncronization issue :

U.Gasparini 3/04/02 2

BTI synchronization

First ideas have been developed (Trigger TDR, CMS-IN 2000/031 ) considering typical L1 trigger rates of ~ 12 KHz in dedicated technical runs (e.g. with ‘single station’ technical trigger), looking to mean-timedistribution as a function of the internal synchronization phase (in “minimal BTI acceptance” configuration)

~1000 ev/chamber/’point’ adequatefor the procedure

P.Zotto at al.

U.Gasparini 3/04/02 3

BTI synchronization

High qualityTrigger efficiency

(caution: curve may be distorted bytime-dependent LHC luminosity)

Meantime r.m.s.

(unaffected by lumi variations)

At 1034, the procedure shouldtake ~ 2h for the barrel detector (plots from MC tracks, normalincidence to the chamber;procedure also tested on H2 testbeam)

MC

P.Zotto at al.

U.Gasparini 3/04/02 4

At DAQ level (i.e. L2 or before (DDU level?)) we’ll likely want to have meantime

distributions in each chamber for different GMT output (eg L1A from DT only, from RPC only)

DT calibration

Drift time distribution,integrated over all SL cells

Tmax from local tracks in a SL (=> drift velocity measurement)

( 6 Hz/m2 prompt muons in MB4, 30 Hz/chamber, ~ 2 KHz rate total )

~ few min. run @ 1033

U.Gasparini 3/04/02 5

• DT calibration flow (M.Dalla Valle, Calibration workshop Sept.’2000): •these run types are currently being considered:

Calibration run type when duration Data volume Processed in Results used by

Thresholds runNo beam

More frequentlyat start-up thenmonthly

30 min(severalconsecutiveruns)

0.2 Mwords(stored)

DAQ farm FE electronics(via DCS)

Relative t0-calibrationNo beam

Before every fill 3 min. 0.2 Mwords(stored)

DAQ farm L2, offline

SynchronisationDuring Physics(clock phase adjustmentper chamber, thenabsolute synch perchamber)

More frequentlyat start-up, thenmonthly

60 min 0.2 Mwords +bunch patternhistograms

Local system(ChamberControl Unit)

FE electronics(via DCS)

Gap testsTest pulses(synchronisation, deadchannels)

In LHC abortgap

Gap length Local DAQ,DAQ farm

Rates(rates with 2 thresholds)

Before every fill 3 min 0.4 Mwords DAQ farm

Alignment with muDuring PhysicsMuon trigger

10000 mu/sector

120 Mwords offline L2, offline

U.Gasparini 3/04/02 6

DT calibration/monitoringWhich “local software tool” we need (and where they run)?How do we spy data?Where the ‘local DAQ path’ will be splitted from the normal DAQ ?

172,200 channels 250 chambers 5x12 = 60 sectors

10,960 FEB

1,440 ROB

60ROS Master

5 DDU

16 channels/FEB

DAQ

On chamber“MINICRATE”In 1 ROB: 4 32-channels TDCs

1 per sector (4 chambers)

1 per 12 ROSM

Opt.link

120Mb/s

U.Gasparini 3/04/02 7

CMS TriDAS layoutDDU

U.Gasparini 3/04/02 8

Final DDU block diagram

ROS

ROS

ROS

ROS

ROS

ROS

ROS

ROS

ROS

ROS

ROS

ROS

fast monitoring

CMS readout

VME - DCS‘FPGAs’

Output FIFOs

Input FIFOsTTC

(R.Cirio, 20/3/2002 PD Electronics meeting)

U.Gasparini 3/04/02 9

DT calibration/monitoring

Which “fast monitoring” we may think of ?

-at DDU level, data from entire sectors available....

- fast meantime analysis @ chamber level

- fast local tracks in chamber (see testbeam online data analysis)

- fast muon reco (‘reduced version’ of L2 reco running in DAQ farm)

U.Gasparini 3/04/02 10

SL test in Legnaro

- fast meantime analysis:

A.Meneguzzo

U.Gasparini 3/04/02 11

Online Event Display

RPCSL 3()

SL 1()

SL 2()

BC 3

BC 2

BC 1Oct.2001

RUN 642

- fast local tracks in chamber (see testbeam online data analysis)

S.Vanini, A.Colaleo

U.Gasparini 3/04/02 12

- fast muon reco (‘reduced version’ of L2 reco running in DAQ farm)

Compare L1 TrackFindervs L2

Where do we foresee to do that?

U.Gasparini 3/04/02 13

DAQ DB RECO

Global MuonTrigger

Local Software Tools

Comparisons between the locally stored input to the Global Muon Trigger and the reconstructed data will be used to calibrate the matching look up tables and to calibrate the look up tables for the candidate selection and ranking

DTTF

RPC

CSCTF

Input Data SpyLUT

Calibration

LUTs calibrationCould also beHLT output...

U.Gasparini 3/04/02 14

Summary

Many ‘on-line’ software items implied by DT calibration/monitoringprocedures

they concern both Trigger & RO systems

understand sharing between local DAQ monitoring & central DAQ

define which methods & tools

develop prototype to be used in next testbeam runs