Difference between revisions of "HRS Checkout (Experts)"
From Hall A Wiki
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</table> | </table> | ||
<ol> | <ol> | ||
| − | <li> With the above kinematics, take a run (at least 100K events or | + | <li> With the above kinematics, take a run (at least 100K events or 15 minutes) and verify that all detector channels are working. |
<li> Using the same run, produce a ROOT tree, and do the following: make a spectrum of x vs. y at the focal plane. What you should see is a "spider" with 5 legs. The non-straightness of the central legs indicates there is an offset in the Z or Y direction. If you don't see a "spider" or something resembling it, then of of the polarities of the HRS magnets is set wrong (or a magnet is off). | <li> Using the same run, produce a ROOT tree, and do the following: make a spectrum of x vs. y at the focal plane. What you should see is a "spider" with 5 legs. The non-straightness of the central legs indicates there is an offset in the Z or Y direction. If you don't see a "spider" or something resembling it, then of of the polarities of the HRS magnets is set wrong (or a magnet is off). | ||
<li> Check that the signals are well timed. | <li> Check that the signals are well timed. | ||
Revision as of 15:55, 26 October 2014
The detector checkout is best done using a fairly uniform illumination, which is provided for by 20 μA on the central Carbon target at the following kinematics:
E' = 2.918 GeV, θ = 22.8 degrees (W2 = 2.40 GeV, Q2 = 3.33 GeV2). The HRS electron rates should be about 90 Hz.
| Ebeam [GeV] | P0 [GeV/c] | θe [deg] | Collimator | Target | Fast Raster X x Y |
Beam Current | Trigger |
| 7.3 | 2.918 | 22.8 | None | Single Carbon | off | 20 μA | S0&&S2m |
- With the above kinematics, take a run (at least 100K events or 15 minutes) and verify that all detector channels are working.
- Using the same run, produce a ROOT tree, and do the following: make a spectrum of x vs. y at the focal plane. What you should see is a "spider" with 5 legs. The non-straightness of the central legs indicates there is an offset in the Z or Y direction. If you don't see a "spider" or something resembling it, then of of the polarities of the HRS magnets is set wrong (or a magnet is off).
- Check that the signals are well timed.
- Determine correct thresholds.
- Verify all scalers are incrementing.
- Check for double pulsing and time the wire chamber signals.
- Are the scintillator signals for on scale in the scintillator ADCs?
- PID threshold checks.
