1 T1-T3 in L1 algorithm  Outlook: I) Summary of L1-confirmation II) About the TrgForwardTracking package III) Confirming (preliminary)  L1-confirmation  L1-upgrade IV) About Patter Recognition with less stations V) Conclusion and plans L1-confirmation summary T1-T3 in L1 algorithm Status Report Jose A. Hernando (16/2/04)  Quick summary: L1-confirmation (L1 as 1 st step of HLT)  ~5% signal eff lost and ½ reduction of mb L1-upgrade (T1,2,3 in L1)  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?

2 (I) Summary: L1 confirmation (or) 1 st 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

3 (II) 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 Tracks (Forward) ForwardTrackAlg HitCreator IT/OT Clusters Planes Tracks (TT) Tracks ForwardTrackTool Track geo L1Buffer geo RawBuffer 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 Planes Hits Planes  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.

4 (II) Trg Forward Tracking: resolution & n. of tracks  tracking performance  _p/p ~ 0.5 % Number of input tracks  Velo+TT 41.2  Forward 22.9  A factor 1.8 tracks reduction Pending a full study of efficiency, ghost and clones rate! sigma_p/p and number of tracks B(pi,pi) Signal tracks Velo+TT (TrgTracks) Forward (TrgTracks)

5 (II) Trg Forward Tracking: timing  Timming (my laptop: PIII 1GHz) Reference:  L1Decision 8.2 (+13) ms  Scaling 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 track  With previous P Info 0.43(+-0.24) ms  Without no P Info 0.6(+-0.44) ms Tracking in track without P Killing clones Forward Algorithm Traking on track with P info

6 (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 sample minbias [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

7 (III) 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) % signal minbias[cross], B(pipi)[dark start], Bs(DsK) [open start] (after L1) Min-bias Log(pt0*pt1) (after L1) % efficiency vs % retiencion B(pipi)[black] Bs(DsK) [open] (after L1) 20 KHz

8 (III) 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% eff  L1-upgrade ~82%  Factor ~1.3 B(pi,pi) –L1global (line L1-VeloTT) (dash: forward) % sample minbias[cross], B(pipi)[dark start], Bs(DsK) [open start] Min-bias L1-global (line: L1:Velo-TT) (dash: Forward) % efficiency vs % retiencion B(pipi)[black] Bs(DsK) [open] (L1 and L1upgrade) 40 KHz

9 (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 (1 st 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) % retention Minbias[cross], B(pipi)[dark start], Bs(DsK) [open start] (L1) Min-bias: log(pt0*pt1) (line: L1:Velo-TT) (dash: Forward) % efficiency vs % retiencion B(pipi)[black] Bs(DsK) [open] (L1 and L1upgrade) 40 KHz

10 (III) Confirming 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)

11 (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 histo ST (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)] channels  Where 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 event Tracks ordered by Pt (velo-TT) PR histogram

12 (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 MCParticle  2) 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):  1 st ) Take the highest peak in one bin (1 st row)  2 nd ) Add neighbor bin to highest peak and continue  3 rd ) 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 (1 st,2 nd,3 rd )? Repeat the study removing stations. Note: in TrgForwardTrack we already have a way to “mask” hits and redo the tracking!!

13 (IV) Peaks of PR histogram with T 1,2,3  The study: For a given:  1) MC: Only the MC hits  2) fake: Remove the MC hits of this particle, (“random” peaks) Method:  Peak in one bin (1 st row)  Add neighbor bin to highest (2 nd )  Add the other neighbor (3 rd )  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 highestpeak Signal[line], fake[dash] # of peaks vs the size [only in fake sample] #of signal peak found [cross] and fakes vs peak height

14 (IV) Peaks of the PR histogram removing T2  Removing T2 hits For a given track  1) MC: Only the MC hits  2) fake: Remove the MC hits of this particle. (random peaks) Method:  Peak in one bin (1 st row)  Add neighbor bin to highest (2 nd )  Add the other neighbor (3 rd )  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) Size of the highestpeak Signal[line], fake[dash] # of peaks vs the size [only in fake sample] #of signal peak found [cross] and fakes vs peak height

15 (IV) Peaks of the PR histogram with only T2  Only T2 hits For a given track  1) MC: Only the MC hits  2) fake: Remove the MC hits of this particle. (random peaks) Method:  Peak in one bin (1 st row)  Add neighbor bin to highest (2 nd )  Add the other neighbor (3 rd )  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? Size of the highestpeak Signal[line], fake[dash] # of peaks vs the size [only in fake sample] #of signal peak found [cross] and fakes vs peak height

16 (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 T2  Feed 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

17 Conclusions and plans:  The Trg (Trigger) Forward Tracking Status:  Is in the “new” Trg code structure  It is working! Planes  Efficiency 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 1 st 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 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 T1,2,3  Signal 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?)