jin huang m.i.t. for transversity analysis meeting jun 18, 2009 @ jlab

Scalar Events Synchronization

2nd Farm Replay Summary

Jin HuangM.I.T.

For Transversity Analysis MeetingJun 18, 2009 @ JLab

&

Jin Huang <[email protected]> 2

• Why do synchronization?• Technical : One way to impalement - TSelector • Application • Beam Trip Cut• BCM Stability Check w/ Beam Trip Cut• Dead Time w/ Beam Trip Cut

Synchronizing Scalar Insertion

• Coin Trigger: LT/LT Asym with/without beam trip cuts• Other Trigger

Dead Time w/ Beam Trip Cut

• Farm Production Summary• Coincident Timing Update

Other

Transversity Analysis Meeting

Out Line


Asymmetry Calculation requires two parts of information:◦ L1A Events Counts (with PID and Kinematics Cut)◦ Scalar Sums (bcm … )

If part of data should be cut away (ex. Beam trip), then Events & Scalar should be cut for exactly same period


Why scalar synchronization?


3 Forms of scalar data insertion 1. Each Event based (DL.*)

automatically synchronized to L1A events Limited information

major trigger gated/ungated bcm u/d3 clocks

2. Every 100 event based Full data set Non-syncronized to each event

3. Every 2s based Full data set Slower comparing with #2


Why scalar synchronization?


Upgrading my old beam trip code producing raw asymmetry to do scalar synchronizationAutomatically generated class base using T->MakeSelector()Automatically loop through whole root file, flexible process: full c++ supportFastest way to go through a root file (backbone for Draw & Scan)Require lots of coding with carefulnessNot for doing simple analysis


Technical : One way to impalement - TSelector


~10% of our data is taken during beam trip◦ Fast Drop; Slower climb◦ Even slower PID lock back to equilibrium current


Application/ Anatomy Beam Trip

Trip

Ram p

Norm

Norm

Lock

Example of an aggressive Trip cutCurrent Calculated Each Scalar Insert

Before Cut

T (min)

Cu

rren

t (u

A)

Scalar Insertion

s

Jin Huang <[email protected]> 7Transversity Analysis Meeting

Application/ Beam Trip Cut

Although there are Bad Days

Average Runs


Average Beam Current w/Beam Cut


BCM u3 vs d3 Diff w/Beam Cut

This Drop persists

This fluctuation Persists


Difference change for different Spin Drift with time?


Zoom in the fluctuation part


Dead time asymmetry is addable correction to physical asymmetry ◦ Comparing with polarization asymmetry, which is

multiplied to physical asymmetry, dead time asym is more important

Dead time change from different beam condition

DAQ LiveTime = 1-DeadTime = NEvents/(Ntrigger/Prescale)

Studied with ~70% of our production data


Dead Time Study w/beam cuts


Live time -> 84~90% after beam cuts


DAQ Live Time

Before Cut

After Cut


Live time is higher during trip and ramp


DAQ Live Time

Trip Part

Ramp Part

Not very high due to aggressive beam cuts


Seems stable


DAQ Live Time Asym, w/trip cut

SSA

DSA


DAQ Live Time Asym, w/trip cut

Sum 600runs, average ~100ppm


DAQ Live Time Asym, w/o trip cut

On same level, Fluctuation is larger


Also for other triggers

T6

T3


Coin Trigger DT is 84%~90% Beam cut improve stability of live time by a

factor of ~2 Overall SSA LT Asym is ~100ppm (small) Single Run SSA LT Asym ~0.1% DT Correction half-pair by half-pair is doable

but not necessary


DAQ Live Time/Summary


the majority of our data are replayed LHRS TOF calibration from Chiranjib (time

walk is not included) final BB MWDC calibration from Xin Scalar variable updates from Kalyan BB Gas Cer variables are added into DL.*

following requests from Joe Target Spin Azimuthal Angle theta_s, phi_s

are calculated


2nd Farm Production


600GB increase in disk space/cleaning of old files -> More free space◦ ~670 (100%) 1M event top quality production runs

from my list. ◦ ~230 (50%) flag-15 production runs from database It

took 48hour to replay on farm with a parallel

processing of 60 runs at the same time. Root files were stored at

◦ Temporary Data Disk Directory: /w/halla/transversity/disk3/ProductionROOTfiles

◦ Permanent MSS Tape Directory: /mss/halla/e06010/ProdReplay2


2nd Farm Production


Y axis is number of events passing a “have track” cuts


Run Distribution


Pion resolution drop from ~400ps -> ~360ps

Limit by BB side (~300- ps)


Coin Time after LHRS Calibration w/o time walk yet

p

K+

Pi+

jin huang m.i.t. for transversity analysis meeting jun 18, 2009 @ jlab

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