1 t1-t3 in l1 algorithm outlook: i) summary of l1-confirmation ii) about the trgforwardtracking...

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T1-T3 in L1 algorithm T1-T3 in L1 algorithm

Outlook:• I) Summary of L1-confirmation

• II) About the TrgForwardTracking package

• III) Confirming (preliminary) L1-confirmationL1-upgrade

• IV) About Patter Recognition with less stations

• V) Conclusion and plans

L1-confirmation summaryL1-confirmation summaryT1-T3 in L1 algorithm Status ReportT1-T3 in L1 algorithm Status Report

Jose A. HernandoJose A. Hernando(16/2/04)(16/2/04)

Quick summary:• L1-confirmation (L1 as 1st step of HLT)

~5% signal eff lost and ½ reduction of mb

• L1-upgrade (T1,2,3 in L1)1.3-1.4 gain in efficiency (40KHz output)4-6 track candidates to forward track

Questions?• How many stations do we need to track?

• What about the time?

• Can we “improve” the confirmation, upgrade?

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(I)(I) Summary: L1 confirmation (or) 1 Summary: L1 confirmation (or) 1stst step of HLT step of HLT

L1 confirmation :• We can reduce the rate to 20 KHz we

with a cost ~5% efficiency

Rough time estimations

(1 GHz PIII)• Redo some L1 calculation

~ 6 ms

• Do the full tacking of some candidates~9 ms

• Current HLT time budget 50 ms

• If we reduce the rate by ½ each L1-confirmed event will have

~35 ms reconstruction~35 ms HLT decision

Efficiency (after L1) vs Output rate

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(II)(II) TrgForwardTracking package TrgForwardTracking package

The basic:• From HltLongTrack package

(O. Callot + N. Arnaud)

• Use TrgTracks from Velo or Velo-TT use TrgProviders

• Separate tracking from hit allocation

• A Tool to forward track a single track candidate

geo Hits

Hits Tracks (Forward)ForwardTrackAlg

HitCreatorIT/OT ClustersPlanes

Tracks (TT)

Tracks ForwardTrackToolTrack

geoL1Buffer

geoRawBuffer

Different versions of the algorithm

L1-Raw(HLT) buffer, or TDR-DaVinci

Common part for TT

Use TrgTracks as Input/Output

It calls the Forward tracking tool

It does clone killing

HitCreator

HitCreator

Planes

HitsPlanes

Status:• It works!

• Final study of efficiency needed

• Plan to incorporate in the repository this week

• Note: separating hits form tracking allow to “mask” input hits.

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(II)(II) Trg Forward Tracking: resolution & n. of tracks Trg Forward Tracking: resolution & n. of tracks

tracking performance_p/p ~ 0.5 %

• Number of input tracks Velo+TT 41.2Forward 22.9A factor 1.8 tracks

reduction

• Pending a full study of efficiency, ghost and clones rate!

sigma_p/p and number of tracksB(pi,pi)

Signal tracks

Velo+TT(TrgTracks)

Forward(TrgTracks)

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(II) (II) Trg Forward Tracking: timingTrg Forward Tracking: timing

Timming • (my laptop: PIII 1GHz) • Reference:

L1Decision 8.2 (+13) msScaling factor

5/8.2 = 0.61• Timer decoding Hits

2.8 (+-4.5) ms• Timing tracking

31 (+-29) ms(P-info) 19 ms

(re-fishing) 11 ms• Tracking successfully a

trackWith previous P Info 0.43(+-0.24) msWithout no P Info 0.6(+-0.44) ms

Tracking in trackwithout P

Killing clones Forward Algorithm

Traking on track with P info

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(III) Confirming L1-confirmation (L1 global variable)(III) Confirming L1-confirmation (L1 global variable)

DaVinci v9r2• L1Decision v2r1

• Zurich: DV v8r3, L1 v2r0

Trigger sequence• HLT-Velo & Velo-TT

• TrgForwardTracking

• L1 from L1Decision

• My TrgDecision Compute IP candidates from

L1 vertex. Compute Pt, IPS and distance Add bonus!!

• Some changes No 400 MeV Pt low limit

Results• We confirm the confirmation

~5% lost in signal and reducing ½ mbias

A little bit worse!?

B(pi,pi) – L1Global(after L1)

% of the sampleminbias [cross] B(pipi) [dark start]Bs(DsK) [open start](after L1)

Min-bias : L1 Global(after L1)

% signal eff vs% retencion B(pipi) [dark] Bs(DsK) [open](after L1)

From now on..PRELIMINARY!!

20 KHz

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(III) (III) Confirming L1-confirmation (log(pt0*pt1))Confirming L1-confirmation (log(pt0*pt1))

DaVinci v9r2• L1Decision v2r1

Same trigger sequence• Now I do not add the

bonus (how?)

Results• We confirm the

confirmation~5% lost in signal

for reducing ½ mbias

A little bit better!Do we open again

(toll) the bonus accounts?

B(pi,pi) Log(pt0*pt1)(after L1)

% signalminbias[cross], B(pipi)[dark start], Bs(DsK) [open start](after L1)

Min-bias Log(pt0*pt1)(after L1)

% efficiency vs % retiencionB(pipi)[black] Bs(DsK) [open](after L1)

20 KHz

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(III) (III) Confirming L1-upgrade (with L1 global)Confirming L1-upgrade (with L1 global)

DaVinci v9r2• L1Decision v2r1• Previous results:

DaVinci v8r3, L1 v2r0 Same trigger sequence

• Compare to L1Decision• Forward Tracking tracks

with (0.15-3mm) respect L1 prim. vertex

• I only consider Tracks with Pt (no 400 MeV)

• My L1 global code.Results

• We confirm L1-upgrade• B(pi,pi) eff

L1 ~62% effL1-upgrade ~82%Factor ~1.3

B(pi,pi) –L1global(line L1-VeloTT)(dash: forward)

% sampleminbias[cross], B(pipi)[dark start],Bs(DsK) [open start]

Min-bias L1-global(line: L1:Velo-TT)(dash: Forward)

% efficiency vs % retiencionB(pipi)[black] Bs(DsK) [open](L1 and L1upgrade)

40 KHz

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(III) Confirming L1-upgrade (with log(pt0*pt1))(III) Confirming L1-upgrade (with log(pt0*pt1))

DaVinci v9r2• L1Decision v2r1• Previous results with:

DaVinci v8r3, L1 v2r0 Same trigger sequence

• L1 from L1Decision• Forward Tracking tracks with

(0.15-3mm) IP (1st Vertex)• I only consider Tracks with Pt

(no 400 MeV)• No Bonus!!• Compute the sum of the pt of

the 2 largest pt track in the IP window

Results• We confirm L1-upgrade• B(pi,pi) eff

L1 ~68% eff L1-upgrade ~86% Factor ~1.26

• L1 a little bit better!?, The bonus?

B(pi,pi) –Log(pt0*pt1)(line L1-VeloTT)(dash: forward)

% retentionMinbias[cross], B(pipi)[dark start],Bs(DsK) [open start](L1)

Min-bias: log(pt0*pt1)(line: L1:Velo-TT)(dash: Forward)

% efficiency vs % retiencionB(pipi)[black] Bs(DsK) [open](L1 and L1upgrade)

40 KHz

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(III) (III) Confirming the confirmation and the upgradeConfirming the confirmation and the upgrade

Confirmation of the confirmation• We have ~5% loss in efficiency for

reducing the output rate by ½ (20 KHz)• A little bit better if we use log(pt0*pt1)

Confirmation of the upgrade• For the channel B(,)

we go from ~62% to ~84%• Similar results with the new forward

package and decision• We confirm the upgrade

ToDo:• More channels• I will like to check the intermediate

distributions! • But It seems that we are in business

Efficiency (after L0) vs Output rate

L1Upgrade(Zurich)

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(IV) The PR search histogram(IV) The PR search histogram

Patter Recognition• Forward Tracking (~somehow)

Using input direction & q/p Define a z-plane ref and a x

window (depending on p)Project x-hits onto that plane

histogram: Callot’s histoST (IT) weight 1.

OT weight 0.5

Use the histo-peaks as seeds

Plan:• Investigate how the PR histogram

behaves with less stations

• Use B(pi,pi), [Bs(Ds,K)] channelsWhere are the 2 largest pt

tracks from the signal?

• I can run the tracking finding tool only with the hits of the MCParticle!

A minbias eventTracks ordered by Pt (velo-TT)

PR histogram

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(IV) The peaks of the PR search histogram(IV) The peaks of the PR search histogram

The study:• For a given track:

We know the MCParticle from the Velo “hits”

• We can make different collection of hits:1) MC: Only the hits associated to the MCParticle2) FC, fake: Remove the MC hits of this particle (will show up “random” peaks)3) RC: all the hits

• Manipulate the PR histogram (to solve the question of the fixed bin-width):1st) Take the highest peak in one bin (1st row)2nd) Add neighbor bin to highest peak and continue3rd) Add now the other neighbor and continue

• Study:What is the highest “peak” of the signal (MC-sample)What is the highest “peak” of the face sample and how many do we have? Is then the signal visible?, in witch histogram (1st,2nd,3rd)?

• Repeat the study removing stations.

• Note: in TrgForwardTrack we already have a way to “mask” hits and redo the tracking!!

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(IV) Peaks of PR histogram with T 1,2,3(IV) Peaks of PR histogram with T 1,2,3

The study:• For a given:

1) MC: Only the MC hits2) fake: Remove the MC hits

of this particle, (“random” peaks)

• Method:Peak in one bin (1st row)Add neighbor bin to highest

(2nd)Add the other neighbor (3rd)

Results for B(pi,pi) • We clearly see the signal!!.

• The best is to “add” 2 bins (2nd)

• There are not many “fake” combinations (~2)

Most likely they will be in evidence in front of the good one

40 KHz

Size of the highestpeakSignal[line], fake[dash]

# of peaks vs the size[only in fake sample]

#of signal peak found [cross]and fakes vs peak height

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(IV) Peaks of the PR histogram removing T2(IV) Peaks of the PR histogram removing T2

Removing T2 hits• For a given track

1) MC: Only the MC hits2) fake: Remove the MC hits

of this particle. (random peaks)

• Method:Peak in one bin (1st row)Add neighbor bin to highest


Results for B(pi,pi) • We still see the signal !!.

• The best is to “add” 2 bins (2n row)

• There are still not many “fake” combinations (~2.5)




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(IV) Peaks of the PR histogram with only T2(IV) Peaks of the PR histogram with only T2

Only T2 hits• For a given track

1) MC: Only the MC hits2) fake: Remove the MC hits of

this particle. (random peaks)• Method:

Peak in one bin (1st row)Add neighbor bin to highest


Results for B(pi,pi) • We do not see the signal.• But there are still not many “fake”

combinations (~2.5)• Not everything is lost:

How “close” is the peak to the “expected” (according with P from Velo-TT)

How “good” is the track produced by the “random” peaks?




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(IV) About PR with less stations(IV) About PR with less stations

From Studying the PR histogram • Combine two bins in one

• T1,2,3 signal clearly visible

• Without T2 signal is still visible

• It seems that there are not many peaks (~2.5) to play.

• It seems that without T2 we should be able to do the tracking

Next steps• Check with Bs(Ds,K) signal.

• Retune the reconstruction parameters without T2Feed the reconstruction tool with only the MC of the track, and

study the variable distributions.Digging deeper in tracking code…

• See if the “distance” of the peak from the “prediction” will help

• See if the “quality” of the peak will help

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Conclusions and plans:Conclusions and plans:

The Trg (Trigger) Forward Tracking• Status:

Is in the “new” Trg code structure It is working!

• PlanesEfficiency studies to be done!Reading from Raw-Buffer pending

(no way from L1-Buffer )

To be incorporated in the repository this week.

L1-confirmation• Redo L1-algorithm as 1st step of HLT

• ~5% efficiency lost and ½ output rate

• We have preliminary confirmed with the “new” forward reconstruction.

• The confirmation works with log(pt-*pt1)

[and what about pt0 only?]

L1 upgrade• A gain factor 1.3-1.4 in efficiency for same

output rate (40 KHz).

• We only need to forward track: 4 or 6 candidates.

• We have preliminary confirmed the upgrade with the “new” forward tracking

• The upgrade works good with the log(pt0*pt1) variable

[what about pt0 alone?]

PR with less station• Studying the peaks from PR histogram

Of course, signal clear with T1,2,3Signal visible after removing T2

• Retune the tracking parameters for the case of no T2.

• Can we ask more?:What about the “distance” to the

prediction (will be P from VeloTT good enough?)

1 t1-t3 in l1 algorithm outlook: i) summary of l1-confirmation ii) about the trgforwardtracking...

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