Difference between revisions of "Fall 2016 LHRS optic plans"
From Hall A Wiki
(→Step L2: Delta Scan with Proton Elastic (with sieve slit)) |
(→Step L4: Proton Elastic Kinematics) |
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* Electron rates assume 9 carbon foils, only 37 out of 155 sieve holes per foil have events (~ 0.41 mSr acceptance), and 8% delta acceptance. | * Electron rates assume 9 carbon foils, only 37 out of 155 sieve holes per foil have events (~ 0.41 mSr acceptance), and 8% delta acceptance. | ||
* Electron rates assume 15 cm LH2 target, only 45 out of 155 sieve holes have events (~ 0.49 mSr acceptance), and 8% delta acceptance. | * Electron rates assume 15 cm LH2 target, only 45 out of 155 sieve holes have events (~ 0.49 mSr acceptance), and 8% delta acceptance. | ||
| − | * Adjust the prescale factors to keep the DAQ deadtime below 10%. | + | * <b>Adjust the prescale factors to keep the DAQ deadtime below 10%</b>. |
* <b>Before moving on to the next target, a GMp expert will determine online how many good electron events have been collected. </b> | * <b>Before moving on to the next target, a GMp expert will determine online how many good electron events have been collected. </b> | ||
<table border="1" style="width:80%"> | <table border="1" style="width:80%"> | ||
| Line 38: | Line 38: | ||
<td>2.217</td> | <td>2.217</td> | ||
<td>1.0</td> | <td>1.0</td> | ||
| − | <td> | + | <td>2 x 2 mm<sup>2</sup></td> |
<td>17.5</td> | <td>17.5</td> | ||
<td>0.20</td> | <td>0.20</td> | ||
| Line 50: | Line 50: | ||
==== Step L2: Delta Scan with Proton Elastic (with sieve slit)==== | ==== Step L2: Delta Scan with Proton Elastic (with sieve slit)==== | ||
| − | * Time estimate: | + | * Time estimate: 1.5 hours |
* Keep the 1-inch tungsten sieve-slit collimator on the front face of the left HRS. | * Keep the 1-inch tungsten sieve-slit collimator on the front face of the left HRS. | ||
| Line 64: | Line 64: | ||
<td>E<SUB>beam</SUB> (GeV)</td> | <td>E<SUB>beam</SUB> (GeV)</td> | ||
<td>k' (GeV)</td> | <td>k' (GeV)</td> | ||
| + | <td>LQ1 (A)</td> | ||
<td>Raster</td> | <td>Raster</td> | ||
<td>θ<SUB>e</SUB> (deg)</td> | <td>θ<SUB>e</SUB> (deg)</td> | ||
| Line 74: | Line 75: | ||
<td>2.217</td> | <td>2.217</td> | ||
<td>2.078</td> | <td>2.078</td> | ||
| − | <td> | + | <td>433.45</td> |
| + | <td>2 x 2 mm<sup>2</sup></td> | ||
<td>17.5</td> | <td>17.5</td> | ||
<td>-4</td> | <td>-4</td> | ||
<td>10,000 (2500 Hz with ps = 4) </td> | <td>10,000 (2500 Hz with ps = 4) </td> | ||
<td>10</td> | <td>10</td> | ||
| − | <td> | + | <td>1M events</td> |
</tr> | </tr> | ||
<tr> | <tr> | ||
<td>2.217</td> | <td>2.217</td> | ||
<td>2.038</td> | <td>2.038</td> | ||
| − | <td> | + | <td>425.11</td> |
| + | <td>2 x 2 mm<sup>2</sup></td> | ||
<td>17.5</td> | <td>17.5</td> | ||
<td>-2</td> | <td>-2</td> | ||
<td>10,000 (2500 Hz with ps = 4)</td> | <td>10,000 (2500 Hz with ps = 4)</td> | ||
<td>10</td> | <td>10</td> | ||
| − | <td> | + | <td>1M events</td> |
</tr> | </tr> | ||
<tr> | <tr> | ||
<td>2.217</td> | <td>2.217</td> | ||
<td>1.998</td> | <td>1.998</td> | ||
| − | <td> | + | <td>416.76</td> |
| + | <td>2 x 2 mm<sup>2</sup></td> | ||
<td>17.5</td> | <td>17.5</td> | ||
<td>0</td> | <td>0</td> | ||
<td>10,000 (2500 Hz with ps = 4)</td> | <td>10,000 (2500 Hz with ps = 4)</td> | ||
| − | <td> | + | <td>10</td> |
| − | <td> | + | <td>1M events</td> |
</tr> | </tr> | ||
<tr> | <tr> | ||
<td>2.217</td> | <td>2.217</td> | ||
<td>1.958</td> | <td>1.958</td> | ||
| − | <td> | + | <td>408.42</td> |
| + | <td>2 x 2 mm<sup>2</sup></td> | ||
<td>17.5</td> | <td>17.5</td> | ||
<td>+2</td> | <td>+2</td> | ||
<td>10,000 (2500 Hz with ps = 4)</td> | <td>10,000 (2500 Hz with ps = 4)</td> | ||
<td>10</td> | <td>10</td> | ||
| − | <td> | + | <td>1M events</td> |
</tr> | </tr> | ||
<tr> | <tr> | ||
<td>2.217</td> | <td>2.217</td> | ||
<td>1.918</td> | <td>1.918</td> | ||
| − | <td> | + | <td>400.08</td> |
| + | <td>2 x 2 mm<sup>2</sup></td> | ||
<td>17.5</td> | <td>17.5</td> | ||
<td>+4</td> | <td>+4</td> | ||
<td>10,000 (2500 Hz with ps = 4)</td> | <td>10,000 (2500 Hz with ps = 4)</td> | ||
<td>10</td> | <td>10</td> | ||
| − | <td> | + | <td>1M events</td> |
</tr> | </tr> | ||
</table> | </table> | ||
| Line 126: | Line 132: | ||
==== Step L3: Dummy Target Runs ==== | ==== Step L3: Dummy Target Runs ==== | ||
| − | * Go back to the ΔP = 0% elastic setting. Make sure the L-HRS P0 = 1. | + | * Go back to the ΔP = 0% elastic setting. Make sure the L-HRS P0 = 1.998 GeV. |
* Move the target to "15 cm Dummy" | * Move the target to "15 cm Dummy" | ||
| − | * Take | + | * Take L-HRS run with same setting as previous step. |
| − | * Take data with this setting for | + | * Take data with this setting for 10 minutes |
<br> | <br> | ||
<table border="1" style="width:80%"> | <table border="1" style="width:80%"> | ||
| Line 135: | Line 141: | ||
<td>E<SUB>beam</SUB> (GeV)</td> | <td>E<SUB>beam</SUB> (GeV)</td> | ||
<td>k' (GeV)</td> | <td>k' (GeV)</td> | ||
| + | <td>LQ1 (A)</td> | ||
<td>Raster</td> | <td>Raster</td> | ||
<td>θ<SUB>e</SUB> (deg)</td> | <td>θ<SUB>e</SUB> (deg)</td> | ||
<td>ΔP (%)</td> | <td>ΔP (%)</td> | ||
| − | <td>Rate [Hz] at | + | <td>Rate [Hz] at 10 μA</td> |
| − | <td> | + | <td>minutes at 10 μA</td> |
<td>Good Electrons</td> | <td>Good Electrons</td> | ||
</tr> | </tr> | ||
<tr> | <tr> | ||
<td>2.217</td> | <td>2.217</td> | ||
| − | <td>1. | + | <td>1.998</td> |
| − | <td> | + | <td>416.76</td> |
| + | <td>2 x 2 mm<sup>2</sup></td> | ||
<td>17.5</td> | <td>17.5</td> | ||
<td>0</td> | <td>0</td> | ||
| − | <td> | + | <td>460</td> |
| − | <td> | + | <td>10</td> |
| − | <td> | + | <td>270k events</td> |
</tr> | </tr> | ||
</table> | </table> | ||
| Line 156: | Line 164: | ||
<br> | <br> | ||
| − | ==== Step L4: | + | ==== Step L4: Proton Elastic Kinematics ==== |
* Time estimate: 1 hour | * Time estimate: 1 hour | ||
| − | * | + | * <b>Trained personnel will be required to remove the 1-inch tungsten sieve-slit collimator from the front face of the HRS</b>. |
| + | * <b>Hall A Technical staff will need to move the left HRS from 17.5 degrees to 42 degrees</b>. | ||
* If you need to increase the spectrometer momentum setting, make sure you cycle Q2 and Q3 as per the cycling procedure. | * If you need to increase the spectrometer momentum setting, make sure you cycle Q2 and Q3 as per the cycling procedure. | ||
| − | * | + | * Elastic electron rates assume 15 μA on 15 cm LH2 target, 5 mSr acceptance. |
| + | * Use the following prescale factors: ps1=1, ps2=1, ps3=1, ps8=100. All other triggers should have zero prescale factor. | ||
| + | * The 15 cm dummy and carbon pointing runs need to be taken at the elastic setting. So keep the momentum as is. | ||
* <b>A GMp expert will check the data quality.</b> | * <b>A GMp expert will check the data quality.</b> | ||
| − | |||
<table border="1" style="width:80%"> | <table border="1" style="width:80%"> | ||
<tr> | <tr> | ||
<td>Target</td> | <td>Target</td> | ||
| + | <td>Raster</td> | ||
<td>E<SUB>beam</SUB> [GeV]</td> | <td>E<SUB>beam</SUB> [GeV]</td> | ||
<td>P<sub>0</sub> [GeV/c]</td> | <td>P<sub>0</sub> [GeV/c]</td> | ||
| − | + | <td>θ<SUB>e</SUB> [deg]</td> | |
| − | <td>θ<SUB>e</SUB> [deg]</td> | + | <td>Q1 current [A]</td> |
<td>Q<SUP>2</SUP> [GeV<SUP>2</SUP>]</td> | <td>Q<SUP>2</SUP> [GeV<SUP>2</SUP>]</td> | ||
| − | <td> | + | <td> Electron Rate [Hz] at 60 μA</td> |
| − | + | <td><b>Minutes</b> at 60 μA</td> | |
| − | <td> | + | |
| − | + | ||
</tr> | </tr> | ||
<tr> | <tr> | ||
| − | <td> | + | <td>15 cm LH2</td> |
| + | <td>2 x 2 mm<sup>2</sup></td> | ||
<td>2.217</td> | <td>2.217</td> | ||
| − | <td>1. | + | <td>1.366</td> |
| − | <td> | + | <td>42.0</td> |
| − | <td> | + | <td>284.93</td> |
| − | <td>1. | + | <td>1.57</td> |
| − | <td>1. | + | <td>1700</td> |
| − | <td> | + | <td>10 (for 1M events)</td> |
| − | <td> | + | </tr> |
| − | <td> | + | <tr> |
| + | <td>15 cm Dummy</td> | ||
| + | <td>2 x 2 mm<sup>2</sup></td> | ||
| + | <td>2.217</td> | ||
| + | <td>1.366</td> | ||
| + | <td>42.0</td> | ||
| + | <td>284.93</td> | ||
| + | <td>1.57</td> | ||
| + | <td>55 at 40 μA</td> | ||
| + | <td>35 (115k events) </td> | ||
</tr> | </tr> | ||
<tr> | <tr> | ||
<td>Single Carbon</td> | <td>Single Carbon</td> | ||
| + | <td>Off</td> | ||
<td>2.217</td> | <td>2.217</td> | ||
| − | <td>1.0</td> | + | <td>1.366</td> |
| − | <td> | + | <td>42.0</td> |
| − | <td> | + | <td>284.93</td> |
| − | <td>1. | + | <td>1.57</td> |
| − | <td>1. | + | <td>200</td> |
| − | <td> | + | <td>10 (for 120k events)</td> |
| − | <td> | + | </tr> |
| − | <td> | + | </table> |
| + | <br> | ||
| + | |||
| + | == Step L5: LHRS 12C overlap white spectra with optics target == | ||
| + | |||
| + | * To be run during with R-HRS optics runs | ||
| + | * Make sure Raster is OFF | ||
| + | * Set prescale so that LT > 70% | ||
| + | * No need to cycle magnets when lowering momentum | ||
| + | |||
| + | <table border="1" style="width:80%"> | ||
| + | <tr> | ||
| + | <td>Target</td> | ||
| + | <td>Raster</td> | ||
| + | <td>E<SUB>beam</SUB> [GeV]</td> | ||
| + | <td>P<sub>0</sub> [GeV/c]</td> | ||
| + | <td>Q1 current [Amps]</td> | ||
| + | <td>θ<SUB>e</SUB> [deg]</td> | ||
| + | <td><b>Minutes</b> at 50 μA</td> | ||
| + | </tr> | ||
| + | <tr> | ||
| + | <td>Optics foils</td> | ||
| + | <td> OFF </td> | ||
| + | <td>2.217</td> | ||
| + | <td>1.080</td> | ||
| + | <td>225.277</td> | ||
| + | <td>42.0</td> | ||
| + | <td>20 (or > 1M events)</td> | ||
| + | </tr> | ||
| + | <tr> | ||
| + | <td>Optics foils</td> | ||
| + | <td> OFF</td> | ||
| + | <td>2.217</td> | ||
| + | <td>1.015 </td> | ||
| + | <td>211.719</td> | ||
| + | <td>42.0</td> | ||
| + | <td>20 (or > 1M events)</td> | ||
| + | </tr> | ||
| + | <tr> | ||
| + | <td>Optics foils</td> | ||
| + | <td> OFF</td> | ||
| + | <td>2.217</td> | ||
| + | <td> 0.954</td> | ||
| + | <td>198.995 </td> | ||
| + | <td>42.0</td> | ||
| + | <td>20 (or > 1M events)</td> | ||
| + | </tr> | ||
| + | <tr> | ||
| + | <td>Optics foils</td> | ||
| + | <td> OFF</td> | ||
| + | <td>2.217</td> | ||
| + | <td> 0.897 </td> | ||
| + | <td> 187.105 </td> | ||
| + | <td>42.0</td> | ||
| + | <td>20 (or > 1M events)</td> | ||
| + | </tr> | ||
| + | <tr> | ||
| + | <td>Optics foils</td> | ||
| + | <td> OFF </td> | ||
| + | <td>2.217</td> | ||
| + | <td> 0.843</td> | ||
| + | <td> 175.841</td> | ||
| + | <td>42.0</td> | ||
| + | <td>20 (or > 1M events)</td> | ||
| + | </tr> | ||
| + | <tr> | ||
| + | <td>Optics foils</td> | ||
| + | <td> OFF </td> | ||
| + | <td>2.217</td> | ||
| + | <td> 0.792</td> | ||
| + | <td> 165.203</td> | ||
| + | <td>42.0</td> | ||
| + | <td>20 (or > 1M events)</td> | ||
| + | </tr> | ||
| + | <tr> | ||
| + | <td>Optics foils</td> | ||
| + | <td> OFF </td> | ||
| + | <td>2.217</td> | ||
| + | <td> 0.745 </td> | ||
| + | <td> 155.400</td> | ||
| + | <td>42.0</td> | ||
| + | <td>20 (or > 1M events)</td> | ||
| + | </tr> | ||
| + | <tr> | ||
| + | <td>Optics foils</td> | ||
| + | <td> OFF </td> | ||
| + | <td>2.217</td> | ||
| + | <td> 0.700</td> | ||
| + | <td>146.013 </td> | ||
| + | <td>42.0</td> | ||
| + | <td>20 (or > 1M events)</td> | ||
</tr> | </tr> | ||
</table> | </table> | ||
<br> | <br> | ||
Latest revision as of 15:34, 17 October 2016
Contents
Step L1: Procedure with Sieve-slit
- Time estimate: 1 hour
* Trained personnel will be required to install the 1-inch tungsten sieve-slit collimator onto the front face of the HRS. * If you need to increase the spectrometer momentum setting, make sure you cycle Q2 and Q3 as per the cycling procedure. * Take sieve-slit runs with the multi-foil carbon target (optics) for the inelastic kinematics in the table. * Electron rates assume 9 carbon foils, only 37 out of 155 sieve holes per foil have events (~ 0.41 mSr acceptance), and 8% delta acceptance. * Electron rates assume 15 cm LH2 target, only 45 out of 155 sieve holes have events (~ 0.49 mSr acceptance), and 8% delta acceptance. * Adjust the prescale factors to keep the DAQ deadtime below 10%. * Before moving on to the next target, a GMp expert will determine online how many good electron events have been collected.
| Target | Ebeam [GeV] | P0 [GeV/c] | Raster | θe [deg] | Q2 [GeV2] | W [GeV] | Rate [Hz] at 60 μA | minutes at 60 μA | Good Electrons |
| Optics | 2.217 | 1.0 | Off | 17.5 | 0.20 | 1.72 | 540 | 32 | 1M events |
| 15 cm LH2 | 2.217 | 1.0 | 2 x 2 mm2 | 17.5 | 0.20 | 1.72 | 4600 | 10.0 | 2.7M events |
Step L2: Delta Scan with Proton Elastic (with sieve slit)
- Time estimate: 1.5 hours
* Keep the 1-inch tungsten sieve-slit collimator on the front face of the left HRS. * Take runs with the 15 cm liquid hydrogen target for the elastic kinematics in the table. * Wait until the left dipole reaches the desired momentum and is stable. * If you need to increase the spectrometer momentum setting, make sure you cycle Q2 and Q3 as per the cycling procedure. * Rate estimates only include elastic electrons and does not include rate from inelastic events or from the target endcaps. * Adjust the prescale factors to keep the DAQ deadtime below 10%. * The Q2 for these settings is 0.41 GeV2.
| Ebeam (GeV) | k' (GeV) | LQ1 (A) | Raster | θe (deg) | ΔP (%) | Rate [Hz] at 10 μA | minutes at 10 μA | Good Electrons |
| 2.217 | 2.078 | 433.45 | 2 x 2 mm2 | 17.5 | -4 | 10,000 (2500 Hz with ps = 4) | 10 | 1M events |
| 2.217 | 2.038 | 425.11 | 2 x 2 mm2 | 17.5 | -2 | 10,000 (2500 Hz with ps = 4) | 10 | 1M events |
| 2.217 | 1.998 | 416.76 | 2 x 2 mm2 | 17.5 | 0 | 10,000 (2500 Hz with ps = 4) | 10 | 1M events |
| 2.217 | 1.958 | 408.42 | 2 x 2 mm2 | 17.5 | +2 | 10,000 (2500 Hz with ps = 4) | 10 | 1M events |
| 2.217 | 1.918 | 400.08 | 2 x 2 mm2 | 17.5 | +4 | 10,000 (2500 Hz with ps = 4) | 10 | 1M events |
Step L3: Dummy Target Runs
- Go back to the ΔP = 0% elastic setting. Make sure the L-HRS P0 = 1.998 GeV.
- Move the target to "15 cm Dummy"
- Take L-HRS run with same setting as previous step.
- Take data with this setting for 10 minutes
| Ebeam (GeV) | k' (GeV) | LQ1 (A) | Raster | θe (deg) | ΔP (%) | Rate [Hz] at 10 μA | minutes at 10 μA | Good Electrons |
| 2.217 | 1.998 | 416.76 | 2 x 2 mm2 | 17.5 | 0 | 460 | 10 | 270k events |
Step L4: Proton Elastic Kinematics
- Time estimate: 1 hour
* Trained personnel will be required to remove the 1-inch tungsten sieve-slit collimator from the front face of the HRS. * Hall A Technical staff will need to move the left HRS from 17.5 degrees to 42 degrees. * If you need to increase the spectrometer momentum setting, make sure you cycle Q2 and Q3 as per the cycling procedure. * Elastic electron rates assume 15 μA on 15 cm LH2 target, 5 mSr acceptance. * Use the following prescale factors: ps1=1, ps2=1, ps3=1, ps8=100. All other triggers should have zero prescale factor. * The 15 cm dummy and carbon pointing runs need to be taken at the elastic setting. So keep the momentum as is. * A GMp expert will check the data quality.
| Target | Raster | Ebeam [GeV] | P0 [GeV/c] | θe [deg] | Q1 current [A] | Q2 [GeV2] | Electron Rate [Hz] at 60 μA | Minutes at 60 μA |
| 15 cm LH2 | 2 x 2 mm2 | 2.217 | 1.366 | 42.0 | 284.93 | 1.57 | 1700 | 10 (for 1M events) |
| 15 cm Dummy | 2 x 2 mm2 | 2.217 | 1.366 | 42.0 | 284.93 | 1.57 | 55 at 40 μA | 35 (115k events) |
| Single Carbon | Off | 2.217 | 1.366 | 42.0 | 284.93 | 1.57 | 200 | 10 (for 120k events) |
Step L5: LHRS 12C overlap white spectra with optics target
- To be run during with R-HRS optics runs
- Make sure Raster is OFF
- Set prescale so that LT > 70%
- No need to cycle magnets when lowering momentum
| Target | Raster | Ebeam [GeV] | P0 [GeV/c] | Q1 current [Amps] | θe [deg] | Minutes at 50 μA |
| Optics foils | OFF | 2.217 | 1.080 | 225.277 | 42.0 | 20 (or > 1M events) |
| Optics foils | OFF | 2.217 | 1.015 | 211.719 | 42.0 | 20 (or > 1M events) |
| Optics foils | OFF | 2.217 | 0.954 | 198.995 | 42.0 | 20 (or > 1M events) |
| Optics foils | OFF | 2.217 | 0.897 | 187.105 | 42.0 | 20 (or > 1M events) |
| Optics foils | OFF | 2.217 | 0.843 | 175.841 | 42.0 | 20 (or > 1M events) |
| Optics foils | OFF | 2.217 | 0.792 | 165.203 | 42.0 | 20 (or > 1M events) |
| Optics foils | OFF | 2.217 | 0.745 | 155.400 | 42.0 | 20 (or > 1M events) |
| Optics foils | OFF | 2.217 | 0.700 | 146.013 | 42.0 | 20 (or > 1M events) |
