Difference between revisions of "Spectrometer Optics First pass 48p75d"

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(→‎Integration with LHRS plan)
(→‎Step R5: Procedure without Sieve-slit)
 
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Line 9: Line 9:
 
<td> LHRS step </td>
 
<td> LHRS step </td>
 
<td> RHRS step </td>
 
<td> RHRS step </td>
−
<td> Approximate RHRS beam time</td>  
+
<td> Approximate beam time</td>  
 
<td> Goals</td>
 
<td> Goals</td>
 
<td> Status</td>
 
<td> Status</td>
Line 16: Line 16:
 
<td>L1 (sieve)</td>
 
<td>L1 (sieve)</td>
 
<td>R1 (sieve)</td>
 
<td>R1 (sieve)</td>
−
<td> 6h   </td>
+
<td> 3h   </td>
 
<td> 60 uA DIS with sieve slit on optics foils and LH2</td>
 
<td> 60 uA DIS with sieve slit on optics foils and LH2</td>
−
<td><b></b></td>
+
<td><b>L1 Completed</b><br>R1 in progress</td>
 
</tr>
 
</tr>
 
<tr>
 
<tr>
 
<td> L2 (sieve)</td>
 
<td> L2 (sieve)</td>
 
<td> </td>
 
<td> </td>
−
<td> 3h </td>
+
<td> 1-2h </td>
 
<td> Elastic Delta Scan on LH2, 10 uA</td>
 
<td> Elastic Delta Scan on LH2, 10 uA</td>
−
<td><b></b></td>
+
<td><b>Completed</b></td>
 
</tr>
 
</tr>
 
<tr>
 
<tr>
Line 32: Line 32:
 
<td> 3-4h </td>
 
<td> 3-4h </td>
 
<td> Elastic Delta Scan on LH2, 60 uA</td>
 
<td> Elastic Delta Scan on LH2, 60 uA</td>
−
<td> </td>
+
<td><b>Completed</b> </td>
 
</tr>
 
</tr>
 
<tr>
 
<tr>
−
<td> </td>
+
<td> L3 (sieve)</td>
 
<td> R3 (no sieve)</td>
 
<td> R3 (no sieve)</td>
 
<td> 1h </td>
 
<td> 1h </td>
 
<td> Elastic dummy  </td>
 
<td> Elastic dummy  </td>
−
<td> </td>
+
<td><b>R3 completed</b><br>L3 skipped</td>
 
</tr>
 
</tr>
 
<tr>
 
<tr>
−
<td> </td>
+
<td> L4 (no sieve) </td>
 
<td> R4 (no sieve)</td>
 
<td> R4 (no sieve)</td>
 
<td> 1h </td>
 
<td> 1h </td>
−
<td> DIS  on single carbon and optics </td>
+
<td> LHRS: elastic LH2, 60 uA<br>
−
<td></td>
+
RHRS: DIS  on single carbon and optics, 60 uA</td>
−
</tr>
+
<td><b>R4 Completed</b><br>L4 not started</td>
−
<tr>
+
−
<td> L4 (sieve) </td>
+
−
<td> R5 (no sieve)</td>
+
−
<td> 5h </td>
+
−
<td> Tungsten wire <br>
+
−
(Needs D. Mekins as wire operator)<br>
+
−
(Needs A. Camsonne as sieve operator)</td>
+
−
<td></td>
+
 
</tr>
 
</tr>
 +
 
</table>
 
</table>
 
<br>
 
<br>
Line 63: Line 56:
  
 
==== Step R1: Procedure with Sieve-slit ====
 
==== Step R1: Procedure with Sieve-slit ====
−
* Time estimate: 6 hours
+
* Time estimate: 3 hours
  
 
  * Trained personnel will be required to install the 1-inch tungsten sieve-slit collimator onto the front face of the HRS.
 
  * Trained personnel will be required to install the 1-inch tungsten sieve-slit collimator onto the front face of the HRS.
Line 76: Line 69:
 
     <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>RQ1</td>
 
     <td>Raster</td>
 
     <td>Raster</td>
 
     <td>&theta;<SUB>e</SUB> [deg]</td>
 
     <td>&theta;<SUB>e</SUB> [deg]</td>
Line 88: Line 82:
 
     <td>2.217</td>
 
     <td>2.217</td>
 
     <td>1.0</td>
 
     <td>1.0</td>
 +
    <td>200.41</td>
 
     <td><b>Off</b></td>
 
     <td><b>Off</b></td>
 
     <td>48.75</td>
 
     <td>48.75</td>
Line 100: Line 95:
 
     <td>2.217</td>
 
     <td>2.217</td>
 
     <td>1.0</td>
 
     <td>1.0</td>
−
     <td>3x3 mm<sup>2</sup></td>
+
     <td>200.41</td>
 +
    <td>2 x 2 mm<sup>2</sup></td>
 
     <td>48.75</td>
 
     <td>48.75</td>
 
     <td>1.51</td>
 
     <td>1.51</td>
Line 124: Line 120:
 
   <tr>
 
   <tr>
 
     <td>E<SUB>beam</SUB> (GeV)</td>
 
     <td>E<SUB>beam</SUB> (GeV)</td>
−
     <td>k' (GeV)</td>  
+
     <td>k' (GeV)</td>
 +
    <td>RQ1</td>
 
     <td>Raster</td>
 
     <td>Raster</td>
 
     <td>&theta;<SUB>e</SUB> (deg)</td>
 
     <td>&theta;<SUB>e</SUB> (deg)</td>
Line 135: Line 132:
 
     <td>2.217</td>
 
     <td>2.217</td>
 
     <td>1.277</td>
 
     <td>1.277</td>
−
     <td>3x3 mm<sup>2</sup></td>
+
     <td>255.93</td>
 +
    <td>2 x 2 mm<sup>2</sup></td>
 
     <td>48.75</td>
 
     <td>48.75</td>
 
     <td>-4</td>
 
     <td>-4</td>
Line 144: Line 142:
 
   <tr>
 
   <tr>
 
     <td>2.217</td>
 
     <td>2.217</td>
−
     <td>1.253</td>  
+
     <td>1.253</td>
−
     <td>3x3 mm<sup>2</sup></td>
+
     <td>251.11</td>
 +
    <td>2 x 2 mm<sup>2</sup></td>
 
     <td>48.75</td>
 
     <td>48.75</td>
 
     <td>-2</td>
 
     <td>-2</td>
Line 154: Line 153:
 
   <tr>
 
   <tr>
 
     <td>2.217</td>
 
     <td>2.217</td>
−
     <td>1.228</td>  
+
     <td>1.228</td>
−
     <td>3x3 mm<sup>2</sup></td>
+
     <td>246.10</td>
 +
    <td>2 x 2 mm<sup>2</sup></td>
 
     <td>48.75</td>
 
     <td>48.75</td>
 
     <td>0</td>
 
     <td>0</td>
Line 164: Line 164:
 
   <tr>
 
   <tr>
 
     <td>2.217</td>
 
     <td>2.217</td>
−
     <td>1.204</td>  
+
     <td>1.204</td>
−
     <td>3x3 mm<sup>2</sup></td>
+
     <td>241.29</td>
 +
    <td>2 x 2 mm<sup>2</sup></td>
 
     <td>48.75</td>
 
     <td>48.75</td>
 
     <td>+2</td>
 
     <td>+2</td>
Line 174: Line 175:
 
   <tr>
 
   <tr>
 
     <td>2.217</td>
 
     <td>2.217</td>
−
     <td>1.179</td>
+
     <td>1.179</td>
−
     <td>3x3 mm<sup>2</sup></td>
+
     <td>236.28</td>
 +
    <td>2 x 2 mm<sup>2</sup></td>
 
     <td>48.75</td>
 
     <td>48.75</td>
 
     <td>+4</td>
 
     <td>+4</td>
Line 196: Line 198:
 
     <td>E<SUB>beam</SUB> (GeV)</td>
 
     <td>E<SUB>beam</SUB> (GeV)</td>
 
     <td>k' (GeV)</td>  
 
     <td>k' (GeV)</td>  
 +
    <td>RQ1</td>
 
     <td>Raster</td>  
 
     <td>Raster</td>  
 
     <td>&theta;<SUB>e</SUB> (deg)</td>
 
     <td>&theta;<SUB>e</SUB> (deg)</td>
Line 205: Line 208:
 
  <tr>
 
  <tr>
 
     <td>2.217</td>
 
     <td>2.217</td>
−
     <td>1.228</td>  
+
     <td>1.228</td>
−
     <td>3x3 mm<sup>2</sup></td>
+
     <td>246.10</td>
 +
    <td>2 x 2 mm<sup>2</sup></td>
 
     <td>48.75</td>
 
     <td>48.75</td>
 
     <td>0</td>
 
     <td>0</td>
Line 243: Line 247:
 
     <td>2.217</td>
 
     <td>2.217</td>
 
     <td>1.0</td>
 
     <td>1.0</td>
−
     <td>173.808</td>
+
     <td>200.41</td>
 
     <td>48.75</td>
 
     <td>48.75</td>
 
     <td>1.51</td>
 
     <td>1.51</td>
Line 255: Line 259:
 
     <td>2.217</td>
 
     <td>2.217</td>
 
     <td>1.0</td>
 
     <td>1.0</td>
−
     <td>173.808</td>
+
     <td>200.41</td>
 
     <td>48.75</td>
 
     <td>48.75</td>
 
     <td>1.51</td>
 
     <td>1.51</td>
Line 266: Line 270:
 
<br>
 
<br>
  
−
==== Step R5: Cross-wire Target Run ====
+
==== Step R5: Procedure without Sieve-slit ====
−
* Time estimate: 5 hours (includes access to install wire target and left HRS Sieve-slit)
+
−
 
+
−
* After the above runs are completed, ask for the target group (call Dave Meekins) to insert the cross-wire target (we are not allowed to do it).
+
−
* '''Target expert will need to go to the Hall and manually move the target in position, so ask for controlled access before starting this step''' 
+
−
* At the same time have the Techs or A. Camsonne install the left HRS sieve-slit.  <b>The right HRS sieve-slit remains off</b>.
+
−
* Take a run with the cross-wire target with 2x2 mm<sup>2</sup> rastered beam, and verify that the beam is centered on the cross-wire target using spot++.
+
−
* If the beam in not centered, then ask MCC to move the beam until the rastered beam spot is centered on the wires.
+
−
* Once beam is centered on the cross-wire target, have MCC turn off the raster.  Make sure the spectrometers still have rates above cosmics by checking <br>the scaler rates.
+
−
* Take a run with the with <b>raster off</b> for both LHRS and RHRS.
+
−
* Electron rates assume 200 &mu;m of tungsten. For LHRS, the rate is only for the central hole of the sieve slit (~ 0.023 mSr acceptance), and 8% delta acceptance.
+
−
* <b>A GMp expert will determine when enough good electron events have been collected.</b>
+
−
 
+
 
<table border="1"  style="width:80%">
 
<table border="1"  style="width:80%">
−
   <tr>
+
   <tr>
−
    <td>Spectrometer</td>
+
 
     <td>Target</td>
 
     <td>Target</td>
−
    <td>Sieve Slit</td>
 
 
     <td>Raster</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>&theta;<SUB>e</SUB> [deg]</td>
+
     <td>Right Q1 Current [A]</td>
−
     <td>Q<SUP>2</SUP> [GeV<SUP>2</SUP>]</td>
+
     <td>&theta;<SUB>e</SUB> [deg]</td>
−
     <td>W [GeV]</td>
+
     <td>Minutes</td>
−
    <td>Rate [Hz] at 1 &mu;A</td>
+
−
    <td>minutes at 1 &mu;A</td>
+
−
    <td> Good Electrons</td>
+
−
  </tr>
+
−
  <tr>
+
−
    <td>Right HRS</td>
+
−
    <td>200 &mu;m tungsten wire</td>
+
−
    <td><b>OUT</b></td>
+
−
    <td><b>Off</b></td>
+
−
    <td>2.301</td>
+
−
    <td>0.75</td>
+
−
    <td>48.74</td>
+
−
    <td>1.18</td>
+
−
    <td>1.617</td>
+
−
    <td>3.28</td>
+
−
    <td>30</td>
+
−
    <td>5.9k events</td>
+
−
  </tr>
+
−
  <tr>
+
−
    <td>Left HRS</td>
+
−
    <td>200 &mu;m tungsten wire</td>
+
−
    <td><b>IN</b></td>
+
−
    <td><b>Off</b></td>
+
−
    <td>2.301</td>
+
−
    <td>1.0</td>
+
−
    <td>16.63</td>
+
−
    <td>0.19</td>
+
−
    <td>1.769</td>
+
−
    <td>1.3</td>
+
−
    <td>30</td>
+
−
    <td>2.3k events</td>
+
 
   </tr>
 
   </tr>
 +
  <tr>
 +
    <td>15cm LH2</td>
 +
    <td>2 x 2 mm<sup>2</sup></td>
 +
    <td>2.217</td>
 +
    <td>1.204</td>
 +
    <td>241.29</td>
 +
    <td>48.75</td>
 +
    <td>Run parallel with LHRS optics step L4</td>
 +
  </tr>
 
</table>
 
</table>
−
<br>
 
−
* After finishing this step ask for Controlled access and call the target expert to move the wire-target out of the way. Also call Hall-A Tech on-call to remove the R-HRS sieve-slit.
 
−
<br>
 

Latest revision as of 15:55, 17 October 2016

If you have questions call Vince Sulkosky or Kalyan Allada, Numbers are on white board


Integration with LHRS plan

LHRS step RHRS step Approximate beam time Goals Status
L1 (sieve) R1 (sieve) 3h 60 uA DIS with sieve slit on optics foils and LH2 L1 Completed
R1 in progress
L2 (sieve) 1-2h Elastic Delta Scan on LH2, 10 uA Completed
R2 (no sieve) 3-4h Elastic Delta Scan on LH2, 60 uA Completed
L3 (sieve) R3 (no sieve) 1h Elastic dummy R3 completed
L3 skipped
L4 (no sieve) R4 (no sieve) 1h LHRS: elastic LH2, 60 uA
RHRS: DIS on single carbon and optics, 60 uA		 R4 Completed
L4 not started


See Left HRS Optics Run Plan

Step R1: Procedure with Sieve-slit

  • Time estimate: 3 hours
* 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.
* 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] RQ1 Raster θe [deg] Q2 [GeV2] W [GeV] Rate [Hz] at 60 μA hours at 60 μA Good Electrons
Optics 2.217 1.0 200.41 Off 48.75 1.51 1.287 14 2 100k events
15 cm LH2 2.217 1.0 200.41 2 x 2 mm2 48.75 1.51 1.287 40.0 1.0 144k events


Step R2: Delta Scan with Proton Elastic (without sieve slit)

  • Time estimate: 3-4 hours
* Trained personnel will be required to remove the 1-inch tungsten sieve-slit collimator from the front face of the HRS.
* Take runs with the 15 cm liquid hydrogen target for the elastic kinematics in the table.
* There will be about a 40 minute time lapse between settings until the right 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. 
* The Q2 for these settings is 1.86 GeV2.
Ebeam (GeV) k' (GeV) RQ1 Raster θe (deg) ΔP (%) Rate [Hz] at 60 μA minutes at 60 μA Good Electrons
2.217 1.277 255.93 2 x 2 mm2 48.75 -4 650 10 390k events
2.217 1.253 251.11 2 x 2 mm2 48.75 -2 650 10 390k events
2.217 1.228 246.10 2 x 2 mm2 48.75 0 650 20 780k events
2.217 1.204 241.29 2 x 2 mm2 48.75 +2 650 10 390k events
2.217 1.179 236.28 2 x 2 mm2 48.75 +4 650 10 390k events


Step R3: Dummy Target Runs

  • Go back to the ΔP = 0% elastic setting. Make sure the R-HRS P0 = 1.228 GeV.
  • Move the target to "15 cm Dummy"
  • Take R-HRS run with same setting as previous step.
  • Take data with this setting for 1 hour


Ebeam (GeV) k' (GeV) RQ1 Raster θe (deg) ΔP (%) Rate [Hz] at 40 μA hours at 40 μA Good Electrons
2.217 1.228 246.10 2 x 2 mm2 48.75 0 19.5 1 70k events


Step R4: Procedure without Sieve-slit

  • Time estimate: 1 hour
* Take a run at the following kinematics without the sieve-slit collimator.
* If you need to increase the spectrometer momentum setting, make sure you cycle Q2 and Q3 as per the cycling procedure.
* Electron rates assume 9 carbon foils or 1 single carbon foil, 5 mSr acceptance, and 8% delta acceptance.
* A GMp expert will check the data quality.
Target Ebeam [GeV] P0 [GeV/c] Right Q1 Current [A] θe [deg] Q2 [GeV2] W [GeV] Rate [Hz] at 60 μA minutes at 60 μA Good Electrons
Optics 2.217 1.0 200.41 48.75 1.51 1.287 250 15 220k events
Single Carbon 2.217 1.0 200.41 48.75 1.51 1.287 56 15 50k events


Step R5: Procedure without Sieve-slit

Target Raster Ebeam [GeV] P0 [GeV/c] Right Q1 Current [A] θe [deg] Minutes
15cm LH2 2 x 2 mm2 2.217 1.204 241.29 48.75 Run parallel with LHRS optics step L4
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