1. Data Taking and Samples
2006
Increasing data taking frequency towards the end
Quasi full-time operation in the low-medium proton energy runs
Some data loss due to various hardware problems
PRC, April 2008

2. Measured Energy Spectrum & Fits
Syn. rad. peak
Measured E spectrum:
- Synchrotron radiation peak
- Black body
- Compton peak
- Bremstrahlung edge
* Each spectrum/bunch/~10s
* Matches with left/right
circular polarized laser
beam
Fits:
- Detector resolution + non-
linearity parameters
- Synchrotron radiation
- Bremstrahlung rate & flux
- Compton rate & flux
- e-beam polarization
Black body
Compton peak
Brem. edge
PRC, April 2008

3. One Example Comparison Cavity-TPOL
Every measurement
corresponds to 1 mn
0.9975±0.0020
PRC, April 2008

4. LPOL-TPOL-Cavity Comparison 2007
!!! All cavity results are still preliminary !!!
- Special rise-time data are not included
- Very short periods (<<1 h) are not shown
PRC, April 2008

5. Preliminary Systematic Studies
Source
dPe (%)
Laser polarization uncertainty
Laser circularity [MOCO position scan]
Laser power variation
Electronic Noise
Detector parameters
Calorimeter position scan in x & y
Synchrotron radiation cut
Blackbody temperature
Beam position scan
e beam energy uncertainty
Total (absolute)
≤1.2
Most of the errors
are conservatively
estimated.
Some of the error
sources are redundant (e.g. calo position scan
with beam position scan).
Error reduction is expected in the future with improved fitting program.
PRC, April 2008

6. Summary, Other Development and Plan
Majority of the cavity data analyzed
Preliminary (conservative) systematic studies performed (~1.2%)
Detailed MC simulation of the calorimeter response carried out
New description of the synchrotron radiation peak using MC input &
other improvements in the fitting program being tried
Final data analysis and precision expected before summer 2008
PRC, April 2008