User name markowitz
Log entry time 04:03:51 on March11,2000
Entry number 36112
keyword=energy widthThe harp scan with the raster off gives a beam size of (x) by (y):
scanner5 120 by 170 microns
scanner6 100 by 86 microns.
Gilles tells me we "choose" the scanner 6 numbers normally. Assuming that the intrinsic beam width really is 100 by 86, then I look at the OTR.
The OTR has 4m dispersion and gives spot sizes of 270 microns by 170 microns (but rms values). At 04:00 am, I forget but let me assume FWHM=2*rms values, then sigma would be 230 by 144 microns. This disagrees with the 86 above, but I note that observationally the OTR was fluctuating second to second so let me assume the value is correct.
Then the OTR corresponds to a beam width of 144 (taken from y of the OTR) added in quadrature to the energy width of 180. If the beam width is 180 microns at a region of dispersion with 4m then the energy width is (180E-6/(4m))=4.5E-5 or 5E-5. This would be sigma.
Although this is not good enough for next year's hypernuclear experiment, it is probably about what the present experiment needs/requested.
FIGURE 1
FIGURE 2
