All plots on this page are produced for a single electron events with pT of 30 GeV/c.

1. Input: one-electron events.
   Generated electrons have fixed pT and zVertex of -30, 0, or +30 cm, and uniform eta and phi distribution. Sample of high pT electrons thrown from different zVertex location over eta range [1,2] are shown here: Z=-30cm , Z=0cm , Z=+30cm.,

2. Assumptions about resolution of detectors.
   * Use: Vertex + new FGT + truncated TPC + ESMD

   
   Assumed location & resolution

   detector	assumed resolution	weight of the point	Remarks
   vertex	200 mu m in X,Y,Z	W=1/(200 mu m)^2	added as a hit
   FST	not used
   FGT	60 mu m in X,Y 10 mu in Z	W=1/(60 mu m)^2	4 disks (see plot) at Z=60,80,100,120 cm Rxy in [3,40] cm
   TPC	1 mm along arc 1 mm in Z	W=1/(1mm)^2	* drop padrow #1 and #13 * drop hits at |Z|>197 cm
   Endcap SMD mock hit *)	1.5 mm in X,Y,Z	W=1/(1.5 mm)^2	at xPoint of Geant helix w/ SMD plane

   *) Based on SMD response study by Jim

3. The following detector configuartions have been considered

   Config	Prim Vertex	FGT disks	TPC *)	Endcap SMD
   A	yes	1234	nH>=4	yes
   B	yes	123	nH>=4	yes
   C	yes	1 3	nH>=4	yes
   D	yes	1 2	nH>=4	yes
   E	yes	1	nH>=4	yes
   F	yes	none	nH>=4	yes
   G	yes	1234	nH>=4	no

   *) if nTPC hits<4 then whole TPC is ignored (all its hits).

4. Each of the detectors provide different # of fit points depending on zVertex, eta, and selected configuration.

   detector	Configurations
   FGT	all 4 disks, config=A,G	only disks 1+2, config=D
   TPC	config=A-G, Note, if nhit<4 TPC is ignored		-
   E-SMD	config=A-F
   sum	Circle fit is performed if nHitSum>=5, as marked by the red line.
   	all 4 disks, config=A,G	only disks 1+2, config=D

5. Quality of the reco 3D tracks (fit of circle+line) is defined based on a difference of the reco direction of primary track at the vertex vs. Geant track direction.

   Track reco efficiency is defined as the ratio of# of reco tracks (N1) w/
   * nFitP>=5, including vertex as a hit
   * delPhi<3 mrad
   * delTheta <3 mrad
   to the # of generated electrons (N0).

   Charge reco efficiency requiers additinal
   * the sign of the reco charge is correct. Track counter is N2.
   No cut on reco pT is imposed.

6. Resulting track, charge reco efficiency and contamination for electrons w/ pt=30 GeV/c.
   Note1, we do not want to be in the yellow sqare.
   Note2, the change of trend of the red data at eta=~2 comes from missing IST/HFT in the model. It will disapear once inner barrels are added.
   Note3, configurations listed in alphabetical order.

   track Eff= N1/N0	charg eff = N2/N0	wrong charge (N2-N1)/N1
   Config A, FGT=1234, ESMD=yes
   Config B, FGT=123, ESMD=yes
   Config C, FGT=1 3, ESMD=yes
   Config D, FGT=12, ESMD=yes
   Config E, FGT=1, ESMD=yes
   Config F, FGT=none, ESMD=yes
   Config G, FGT=1234, ESMD=no

7. Conclusions
   1. 4 GEM disks are the bare minimum to get reco tracks at eta <2.0 (compare config A with F or B)
   2. SMD hit does ot matter for track reco (G vs. A), but will matter for charge reco -below.
   3. Not much difference if used GFT disk 1+2 vs. 1+3 (C vs. D)

8. Next steps
   1. Increasy TPC hit threshold to 6 or more. Pileup in TPC will be hard to resolve.
   2. Add 2 GEM disks. Spread them over Z=[60,135] cm. It allows for some redundancy in fast detector only track reco.

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