1. Recent works on AMS
TANG Zhi-Cheng

2. Outline
Detector overview
Proton measurement

3. Detector overview
to check and monitor the situation and performance of AMS detector from fly data
Based on statistics of detector hit distribution and reco object distribution
Run automatically at CERN LSF

4. Accumulate data plots daily data rate accumulate events number
daily event number

5. AMS fly overview
Live time
No. of events
Fly time

6. Hits distribution of sub-detectors(1)

7. Hits distribution of sub-detectors(2)

8. Ecal reconstruction objects

9. Event count distributions of reco particles R > 20 GeV
Particle direction
(galactic coordinate)
AMS position
(geographic coordinate)

10. Proton spectrum: first try

11. Measurement schema data exposure time &event selection: selection
reco spetrum
data
selection
efficiency:
reco
spectrum
unfolding
incident
spectrum
geometry factor
proton spectrum

12. Event selection proton trigger path particle reconstruction selection
bit2 || bit5 ( FTC+Anti || FTC+FTE )
particle reconstruction selection
1 particle with track
beta>0 && charge=1
track selection
event.ntrk=1
layer8 && layer9
nhitY>=5 && nhitXY>=4
NoMSchi2 < *ln(R)
nTofCluster=4

13. Geomagnetic cut and livetime
cutoff=1.2×15 ×cos4(thetaM)
adjust according to binning
ignore events below cutoff
reduce exposure time for rigidity below cutoff
Live time
Exposure time

14. Preliminary Spectrum Selected Events Proton Event rate
Momentum distribution
Proton Event rate
Futher works includes efficiency, geometry factor,
and unfolding

15. Thanks