Charge reco efficiency for 40 GeV e- using 6-disk FGT as on December 2007
Updated: December 15,2007

  1. Assumptions about resolution of detectors.
    * Use: Vertex, IST1+2, SSD, 6-disk FGT, truncated TPC(nHit>=5), ESMD
    detector assumed resolution weight of the point Remarks
    vertex 200 mu m in X,Y
    30 cm in Z
    W=1/(200 mu m)^2 added as a hit
    IST1 20 mum in r*phi
    0.5 mm in Z
    W=1/(20 mu m)^2 -
    IST2 0.5 mm in r*phi
    20 mum in Z
    W=1/(0.5 mm)^2 -
    SSD 20 mum in r*phi
    1 mm in Z
    W=1/(20 mu m)^2 -
    FGT 60 mu m in X,Y
    1 mm in Z
    W=1/(60 mu m)^2 6 disks
    hit reco eff=100%
    TPC 1 mm along arc
    1 mm in Z
    * drop padrow #1 and #13
    * drop hits at |Z|>197 cm
    * drop all hits if below 5
    Endcap SMD
    mock hit **)
    1.5 mm in X,Y
    5mm in Z
    W=1/(1.5 mm)^2 at xPoint of Geant helix
    w/ SMD plane

  2. 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.

  3. Sketch of possible FGT gometries, each consisting of 6 disks.
    * 'large-layout', disks encoded in UPGR13, Z1=60,..., Z6=150cm, DZ=18 cm, Rin=7.5cm, Rout=43 cm
    * 'realistic-layout', disks drawn in magenta, Z1=60,..., Z6=120cm, DZ=10 cm, Rin=~11.5cm, Rout=~38 cm
    * 'compact-layout', disks drawn in green, Z1=60,..., Z6=120cm, DZ=10 cm, Rin=~20cm, Rout=~38 cm

  4. Hits distribution, track, charge reco efficiencies for single electrons with ET of 40 GeV.
    1. DETAILS of : Z1=70,..., Z6=150cm, DZ=16 cm, Rin=11.5cm, Rout=37.6 cm
    2. DETAILS of : Z1=70,..., Z6=120cm, DZ=10 cm, Rin=11.5cm, Rout=37.6 cm
    3. DETAILS of : Z1=70,..., Z6=120cm, DZ=10 cm, Rin=18cm, Rout=37.6 cm
    4. DETAILS of : Z1=110,..., Z6=160cm, DZ=10 cm, Rin=11.5cm, Rout=37.6 cm