1. The focusing mirror system
TOF
Reflecting
inside
direct &
reflected
Low material
budget
Minimize
detector area (~1 m2/sector)
interference with FTOF
spherical (elliptical) mirror within gap volume for backward refl.
plane mirror just beyond radiator for forward reflections
Preliminary studies with mirrors (to reduce instrumented area):
- focalization capabilities shown
- ring patterns for positive and negative mesons at different angles and momenta reconstructed
Different scenarios (refractive index, radiator thickness, mirror geometry) are being explored

2. Hit prob >
Hit prob

3. Unidentified events:
reduced by better treatment of unwanted events
(i.e. muon from meson decay)
Mismatch in number of N p.e.:
wrong seed assignment
Protons weird probability:
feature of the LH definition close to the threshold

4. Direct ring example: Hit prob > 3 10-3 Hit prob
200 trials per point
Aerogel:
- n=1.06
- thick. increasing
with radius: cm
Mirror: 14-25o
PMTs: UBA
Hit prob

5. Hybrid ring example: Hit prob > 3 10-3 Hit prob
200 trials per point
Aerogel:
- n=1.06
- thick. increasing
with radius: cm
Mirror: 14-25o
PMTs: UBA
Hit prob

6. Average N p.e. : Mirror 14-25o PMTs: UBA
200 trials per point
Aerogel:
- n=1.06
- thick. increasing
with radius: cm
N p.e. > 5 for reflected rings
N p.e. > 12 for direct rings

7. LHp-LHk,p : Mirror 14-25o PMTs: UBA
200 trials per point
Aerogel:
- n=1.06
- thick. increasing
with radius: cm
Low angles more challenging
Possibly due to limited
number of trials
Protons benefit the small
number of unfired PMTs
whit expected signal
(P is small when C=0) -

8. Average N p.e. : Mirror 14-25o PMTs: UBA
200 trials per point
Aerogel:
- n=1.06
- thick. increasing
with radius: cm
Mandatory for positive hadrons
Benefit for negative hadrons
at large angles and small energy
Big dot = studies show
in the previous slide

9. Average N p.e. : PMTs: UBA Mirror 14-25o Mirror 14-35o
Worse for positive hadrons
Better for negative hadrons

10. LHp-LHk,p : PMTs: UBA Mirror 14-25o Mirror 14-35o
Worse for positive hadrons
Better for negative hadrons

11. Average N p.e. : PMTs: UBA 200 trials per point Aerogel: - n=1.06
- thick. increasing
with radius: cm
Mirror up to 35o:
Worse for positive hadrons
Better for negative hadrons

12. Average N p.e. : Mirror 14-25o PMTs: UBA
Aer. thick cm
n=1.06
Aer. thick cm
n=1.03 gives less photons regardeless the increase
thickness due to same assumed transmission length

13. LHp-LHk,p : Mirror 14-25o PMTs: UBA
n=1.03
Aer. thick cm
n=1.06
Aer. thick cm
n=1.03 still good due to the larger Cherenkov angle separation

14. Average N p.e. : PMTs: UBA 200 trials per point Aerogel: - n=1.06
- thick. increasing
with radius: cm
n=1.06 better for patter
recognition in the presence
of backgrouns

15. Wrong ID example: Hit prob > 3 10-3 Hit prob 200 trials per point
Aerogel:
- n=1.06
- thick. increasing
with radius: cm
Mirror: 14-25o
PMTs: UBA
Hit prob