Difference between revisions of "Spectrometer Optics 2pass 48p8d"

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==== Procedure with Sieve-slit ====
 
==== Procedure with Sieve-slit ====
−
* Time estimate: 10 hours
+
* Time estimate: 11 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.
 
  * Take a sieve slit run with the multi-foil carbon target for the inelastic kinematics in the table.
 
  * 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.
 
  * 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.
 
 
  * Electron rates assume 5 carbon foils, only 37 out of 155 sieve holes per foil have events (~ 0.4 mSr acceptance), and 8% delta acceptance.
 
  * Electron rates assume 5 carbon foils, only 37 out of 155 sieve holes per foil have events (~ 0.4 mSr acceptance), and 8% delta acceptance.
 
  * Electron rates assume 2 aluminum foils, only 43 out of 155 sieve holes per foil have events (~ 0.47 mSr acceptance), and 8% delta acceptance.
 
  * Electron rates assume 2 aluminum foils, only 43 out of 155 sieve holes per foil have events (~ 0.47 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.
 
<table border="1"  style="width:80%">
 
<table border="1"  style="width:80%">
 
   <tr>
 
   <tr>
Line 88: Line 88:
 
     <td>3.5</td>
 
     <td>3.5</td>
 
     <td>4 (for 50k events)</td>
 
     <td>4 (for 50k events)</td>
 +
  </tr>
 +
  <tr>
 +
    <td>15 cm LH2</td>
 +
    <td>2.301</td>
 +
    <td>0.75</td>
 +
    <td>153.36</td>
 +
    <td>48.74</td>
 +
    <td>1.18</td>
 +
    <td>1.617</td>
 +
    <td>20.0</td>
 +
    <td>1 (for 72k events)</td>
 
   </tr>
 
   </tr>
 
</table>
 
</table>
Line 93: Line 104:
  
 
==== Delta Scan with Proton Elastic ====
 
==== Delta Scan with Proton Elastic ====
−
* Time estimate: 3-4 hours
+
* Time estimate: 3 hours
  
−
  * Trained personnel will be required to remove the 1-inch lead sieve-slit collimator onto the front face of the HRS.
+
  * Trained personnel will be required to remove the 1-inch tungsten sieve-slit collimator from the front face of the HRS.
 
  * Take a run with the 15 cm liquid hydrogen target for the elastic kinematics in the table.
 
  * Take a run with the 15 cm liquid hydrogen target for the elastic kinematics in the table.
 
  * There will be a time lapse between settings until the right dipole reaches the desired momentum and is stable.
 
  * There will be a 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.
 
  * 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 inelastic rate or rate from the target endcaps.  
 
  * Rate estimates only include elastic electrons and does not include inelastic rate or rate from the target endcaps.  
−
  * The Q<sup>2</sup> for these settings is 1.65 GeV<sup>2</sup>.
+
  * The Q<sup>2</sup> for these settings is 1.96 GeV<sup>2</sup>.
  
 
<table border="1"  style="width:80%">
 
<table border="1"  style="width:80%">
Line 106: Line 117:
 
     <td>E<SUB>beam</SUB> (GeV)</td>
 
     <td>E<SUB>beam</SUB> (GeV)</td>
 
     <td>k' (GeV)</td>  
 
     <td>k' (GeV)</td>  
 +
    <td>Right Q1 Current [A]</td>
 
     <td>&theta;<SUB>e</SUB> (deg)</td>
 
     <td>&theta;<SUB>e</SUB> (deg)</td>
 
     <td>&Delta;P (%)</td>
 
     <td>&Delta;P (%)</td>
 
     <td> Rate [Hz] at 20 &mu;A</td>
 
     <td> Rate [Hz] at 20 &mu;A</td>
−
     <td> minutes for 240k events at 20 &mu;A</td>
+
     <td> minutes for 220k events at 20 &mu;A</td>
 
   </tr>
 
   </tr>
 
   <tr>
 
   <tr>
−
     <td>2.057</td>
+
     <td>2.301</td>
−
     <td>1.224</td>  
+
     <td>1.304</td>
 +
    <td>266.64</td>
 
     <td>48.74</td>
 
     <td>48.74</td>
 
     <td>-4</td>
 
     <td>-4</td>
−
     <td>339</td>
+
     <td>176</td>
−
     <td>12</td>
+
     <td>21</td>
 
   </tr>
 
   </tr>
 
   <tr>
 
   <tr>
−
     <td>2.057</td>
+
     <td>2.301</td>
−
     <td>1.201</td>  
+
     <td>1.279</td>
 +
    <td>261.53</td>
 
     <td>48.74</td>
 
     <td>48.74</td>
 
     <td>-2</td>
 
     <td>-2</td>
−
     <td>339</td>
+
     <td>176</td>
−
     <td>12</td>
+
     <td>21</td>
 
   </tr>
 
   </tr>
 
   <tr>
 
   <tr>
−
     <td>2.057</td>
+
     <td>2.301</td>
−
     <td>1.177</td>  
+
     <td>1.254</td>
 +
    <td>256.42</td>
 
     <td>48.74</td>
 
     <td>48.74</td>
 
     <td>0</td>
 
     <td>0</td>
−
     <td>339</td>
+
     <td>176</td>
−
     <td>12</td>
+
     <td>21</td>
 
   </tr>
 
   </tr>
 
   <tr>
 
   <tr>
−
     <td>2.057</td>
+
     <td>2.301</td>
−
     <td>1.154</td>  
+
     <td>1.229</td>
 +
    <td>251.3</td>
 
     <td>48.74</td>
 
     <td>48.74</td>
 
     <td>+2</td>
 
     <td>+2</td>
−
     <td>339</td>
+
     <td>176</td>
−
     <td>12</td>
+
     <td>21</td>
 
   </tr>
 
   </tr>
 
   <tr>
 
   <tr>
−
     <td>2.057</td>
+
     <td>2.301</td>
−
     <td>1.131</td>  
+
     <td>1.203</td> 
 +
    <td>245.99</td>
 
     <td>48.74</td>
 
     <td>48.74</td>
 
     <td>+4</td>
 
     <td>+4</td>
−
     <td>339</td>
+
     <td>176</td>
−
     <td>12</td>
+
     <td>21</td>
 
   </tr>
 
   </tr>
 
</table>
 
</table>
−
 
+
<br>
−
For each &Delta;P (%) setting, we want to take 3 runs with different Q1 currents:
+
−
 
+
−
For &Delta;P = -4%, we want the following Q1 currents:
+
−
<ol>
+
−
<li> -5%: 247.6764 A</li>
+
−
<li> -4%: 250.2835 A</li>
+
−
<li> +5%: 273.7476 A</li>
+
−
</ol>
+
−
 
+
−
For &Delta;P = -2%, we want the following Q1 currents:
+
−
<ol>
+
−
<li> -5%: 243.0224 A</li>
+
−
<li> -4%: 245.5805 A</li>
+
−
<li> +5%: 268.6037 A</li>
+
−
</ol>
+
−
 
+
−
For &Delta;P = 0%, we want the following Q1 currents:
+
−
<ol>
+
−
<li> -5%: 238.1660 A</li>
+
−
<li> -4%: 240.6730 A</li>
+
−
<li> +5%: 263.2361 A</li>
+
−
</ol>
+
−
 
+
−
For &Delta;P = +2%, we want the following Q1 currents:
+
−
<ol>
+
−
<li> -5%: 233.5119 A</li>
+
−
<li> -4%: 235.9699 A</li>
+
−
<li> +5%: 258.0921 A</li>
+
−
</ol>
+
−
 
+
−
For &Delta;P = +4%, we want the following Q1 currents:
+
−
<ol>
+
−
<li> -5%: 228.8579 A</li>
+
−
<li> -4%: 231.2669 A</li>
+
−
<li> +5%: 252.9482 A</li>
+
−
</ol>
+
  
 
==== Proton Elastic Run and Dummy Target Runs====
 
==== Proton Elastic Run and Dummy Target Runs====
  
−
* Go back to the &Delta;P = 0% elastic setting. Make sure the L-HRS P0 = 1.177 GeV and Q1 current = 240.6730 A (-4%)
+
* Go back to the &Delta;P = 0% elastic setting. Make sure the R-HRS P0 = 1.254 GeV and Q1 current = 256.42 A (-4%)
−
* Take data with this setting for 1 hour
+
* Take data with this setting for 1-2 hours
 
<br>
 
<br>
 
<table border="1"  style="width:80%">
 
<table border="1"  style="width:80%">
Line 205: Line 186:
 
   </tr>
 
   </tr>
 
  <tr>
 
  <tr>
−
     <td>2.057</td>
+
     <td>2.301</td>
−
     <td>1.177</td>  
+
     <td>1.254</td>  
 
     <td>48.74</td>
 
     <td>48.74</td>
 
     <td>0</td>
 
     <td>0</td>
−
     <td>339</td>
+
     <td>176</td>
−
     <td>~ 60 mins </td>
+
     <td>~ 105 mins </td>
 
   </tr>
 
   </tr>
 
</table>
 
</table>
Line 216: Line 197:
 
<br>  
 
<br>  
 
* Move the target to "Dummy"
 
* Move the target to "Dummy"
−
* Take L-HRS run with same setting as previous step. We need at least 200 K events.
+
* Take R-HRS run with same setting as previous step. We need at least 200 K events.

Latest revision as of 19:39, 22 January 2016

Procedure without Sieve-slit

  • Time estimate: 1 hour
* Take a run at the following kinematics without the sieve-slit collimator.
* Start with initial right HRS spectrometer tune with the SOS quad in place of right Q1.
* If you need to increase the spectrometer momentum setting, make sure you cycle Q2 and Q3 as per the cycling procedure.
* Electron rates assume 5 carbon foils or 2 Al dummy foils, 5 mSr acceptance, and 8% delta acceptance.
* A GMp expert will check the data quality and decide, if the right HRS tune needs to be adjusted to change the size of the acceptance.
* This process will be repeated until the spectrometer tune is satisfactory.
Target Ebeam [GeV] P0 [GeV/c] Right Q1 Current [A] θe [deg] Q2 [GeV2] W [GeV] Rate [Hz] at 20 μA minutes for 50k events at 20 μA
Optics 2.301 0.75 153.36 48.74 1.18 1.617 70.5 12
4 cm Dummy 2.301 0.75 153.36 48.74 1.18 1.617 37.4 22


Procedure with Sieve-slit

  • Time estimate: 11 hours
* Trained personnel will be required to install the 1-inch tungsten 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.
* Electron rates assume 5 carbon foils, only 37 out of 155 sieve holes per foil have events (~ 0.4 mSr acceptance), and 8% delta acceptance.
* Electron rates assume 2 aluminum foils, only 43 out of 155 sieve holes per foil have events (~ 0.47 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.
Target Ebeam [GeV] P0 [GeV/c] Right Q1 Current [A] θe [deg] Q2 [GeV2] W [GeV] Rate [Hz] at 20 μA hours at 20 μA
Optics 2.301 0.75 153.36 48.74 1.18 1.617 5.6 5 (for 100k events)
4 cm Dummy 2.301 0.75 153.36 48.74 1.18 1.617 3.5 4 (for 50k events)
15 cm LH2 2.301 0.75 153.36 48.74 1.18 1.617 20.0 1 (for 72k events)


Delta Scan with Proton Elastic

  • Time estimate: 3 hours
* Trained personnel will be required to remove the 1-inch tungsten sieve-slit collimator from the front face of the HRS.
* Take a run with the 15 cm liquid hydrogen target for the elastic kinematics in the table.
* There will be a 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 inelastic rate or rate from the target endcaps. 
* The Q2 for these settings is 1.96 GeV2.
Ebeam (GeV) k' (GeV) Right Q1 Current [A] θe (deg) ΔP (%) Rate [Hz] at 20 μA minutes for 220k events at 20 μA
2.301 1.304 266.64 48.74 -4 176 21
2.301 1.279 261.53 48.74 -2 176 21
2.301 1.254 256.42 48.74 0 176 21
2.301 1.229 251.3 48.74 +2 176 21
2.301 1.203 245.99 48.74 +4 176 21


Proton Elastic Run and Dummy Target Runs

  • Go back to the ΔP = 0% elastic setting. Make sure the R-HRS P0 = 1.254 GeV and Q1 current = 256.42 A (-4%)
  • Take data with this setting for 1-2 hours


Ebeam (GeV) k' (GeV) θe (deg) ΔP (%) Rate [Hz] at 20 μA minutes for 1M events at 20 μA
2.301 1.254 48.74 0 176 ~ 105 mins


  • Move the target to "Dummy"
  • Take R-HRS run with same setting as previous step. We need at least 200 K events.
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