User name R. Michaels
Log entry time 09:23:14 on October16,2005
Entry number 157092
keyword=dipole scan, upwardsDipole scan, going UP. This is our usual scan, and we do the
"detune algorithm" described in halog 157053 (see also 156713).
dP (%) ... P (MeV) ... Spectr. DAQ Run
0 ....... 3123.4 .... 2857 .... baseline
2 % ..... 3186 ...... 2858
... repeat .......... 2859 .... better PS factor (want T4s)
4 % ..... 3248 ...... 2860
8 % ..... 3373 ...... 2861
... repeat .......... 2862 .... set PS for T4 = 1
12 % .... 3498....... 2863
15 % .... 3592 ...... 2864
20 % .... 3748 ...... 2865
After this, we switch to HAPPEX DAQ and step back to 0%.
Ask for 50 uA.
dP ...... P ..... HAPPEX run
20 % .... 3748 .... 5659
15 % .... 3592 .... 5660
12 % .... 3498 .... 5661
8 % ..... 3373 .... 5662
4 % ..... 3248 .... 5663
2 % ..... 3186 .... 5664
0 % ..... 3123.4 .. 5665 ... 50 uA at nominal setting of experiment
Rescattering function plotted in fig 1.
An upper limit to the delta background can be estimated.
Using the inelastic spectra (subtracting radiative tail) the
integrated delta resonance is less than 2% of the elastic peak,
see halog 157053. At that dP the rescattering is less than 1e-3.
So, the background from delta is < 2e-5. We expected it to be
very small for this low Q2. As for the disagreement
between counting and integrating, I would not get too excited yet.
For one thing I need to recheck counting mode analysis; but in
general the integrating method is most reliable for known reasons.
Scan finished.
NOTE: I did *NOT* cycle Q2, Q3.
FIGURE 1
