Spectrometer Optics
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Revision as of 13:10, 14 October 2014 by Vasulk (Talk | contribs) (New page: ==== Procedure with Sieve-slit ==== * A Hall A Tech may be required to install the 2-inch lead sieve-slit collimator onto the front face of the HRS. * Take a sieve slit run with the mult...)
Procedure with Sieve-slit
* A Hall A Tech may be required to install the 2-inch lead sieve-slit collimator onto the front face of the HRS. * Take a sieve slit run with the multi-foil carbon target for the inelastic kinematics in the table. * If you need to increase the spectrometer momentum setting, make sure you cycle Q2 and Q3 as per the cycling procedure. * Repeat the above with the beam position shifted so that you see a vertical shift by one row. * Rates assume 5 carbon foils, only 9 out of 25 sieve holes have events (~ 0.146 mSr acceptance), and 9% delta acceptance.
| Ebeam [GeV] | P0 [GeV/c] | θe [deg] | Q2 [GeV2] | W [GeV] | Rate [Hz] at 20 μA | minutes for 100k events at 20 μA |
| 7.3 | 3.200 | 19.0 | 2.5 | 2455 | 15 | 110 |
| 7.3 | 2.019 | 19.0 | 1.6 | 3030 | 24 | 70 |
Alternative rates with 1-inch tungsten sieve slit: * Assumes that 49 out of the 63 holes are seen (~ 0.52 mSr acceptance); however, the acceptance is reduced by 85%,
since not all foils will see all holes. * Rates assume 5 carbon foils and 9% delta acceptance.
| Ebeam [GeV] | P0 [GeV/c] | θe [deg] | Q2 [GeV2] | W [GeV] | Rate [Hz] at 20 μA | minutes for 200k events at 20 μA |
| 7.3 | 3.056 | 19.0 | 2.4 | 2533 | 58 | 58 |
