1) g11  10% background

Tracking efficiency:  64.6%

(exactly one track in central 6x6 mm area at front tracker and back tracker)

Ambiguous events:     0%

(more than one track in central 20x200 mm)

2) g12   25% background

Tracking efficiency:  55.6%
Ambiguous events:     0%

3) g13   50% background

Tracking efficiency:  39.3%
Ambiguous events:     0.14%

4) g14   100% background

Tracking efficiency:  18.1%
Ambiguous events:     3.1%

Parameters (for reference/expert use):

number replayed = 5000

search_depth = 12
3d_ampcorr_maxmiss = 4
3d_ampcorr_nsigma = 0.18
3d_chi2_conflevel = 1e-6
3d_maxmiss = 4
maxmiss  = 3
maxpat   = 1000
maxslope = 0.1
chi2_conflevel = 1e-6
xp.res       = 7e-5
maxclustsiz  = 4
adc.min      = 200
split.frac   = 0.1
maxhits      = 1000
maxsamp      = 3
adc.sigma    = 0.2