Difference between revisions of "Run Plan for Kaon LT Luminosity Scan"

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Line 30: Line 30:
 
=== 1 - 55uA LH<sub>2</sub> ===
 
=== 1 - 55uA LH<sub>2</sub> ===
 
# LH<sub>2</sub> target (unchanged)
 
# LH<sub>2</sub> target (unchanged)
−
# '''Request 70uA'''; run at highest current available if we can't reach 70uA (likely)
+
# '''Request 55uA'''; run at highest current available if we can't reach 55uA (likely)
−
# '''If running at 70uA: switch OFF SHMS DCs''': expecting ~1MHz SHMS singles rate which will trip the DCs
+
# '''If running at 55uA: switch OFF SHMS DCs''': expecting ~1MHz SHMS singles rate which will trip the DCs
 
## '''Else: keep DCs ON and carefully monitor if running at lower current''': ~55uA is the highest current we know we should be able to run without issues in this setting, but it is currently unknown at which exact current between 55uA-60uA the DCs start to trip.
 
## '''Else: keep DCs ON and carefully monitor if running at lower current''': ~55uA is the highest current we know we should be able to run without issues in this setting, but it is currently unknown at which exact current between 55uA-60uA the DCs start to trip.
 
# Try to take a good 12min run with minimal trips
 
# Try to take a good 12min run with minimal trips
Line 40: Line 40:
  
 
=== 2 - C-1.5% Scan ===
 
=== 2 - C-1.5% Scan ===
 +
# '''Change target to C-1.5%'''
 
# '''REQUEST 55uA'''
 
# '''REQUEST 55uA'''
−
## '''Change target to C-1.5%'''
+
## run at highest current available if we can't reach 55uA
−
## '''Request 55uA'''; run at highest current available if we can't reach 65uA (likely)
+
## '''Ensure SHMS DCs are ON and carefully monitor'''
−
## '''Ensure SHMS DCs are ON and carefully monitor''': rate should be bit lower
 
 
### '''If tripping is an issue, turn SHMS DCs OFF'''
 
### '''If tripping is an issue, turn SHMS DCs OFF'''
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
Line 56: Line 56:
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
  
−
=== 3. - LH2 Scan (con't) ===
+
=== 3 - 30uA Dummy ===
 +
# '''Change target to Al Dummy'''
 +
# '''REQUEST 30uA'''
 +
## Try to take a good 12min run with minimal trips
 +
 
 +
=== 4. - LH2 Scan (con't) ===
 
# '''Change target to LH<sub>2</sub>'''
 
# '''Change target to LH<sub>2</sub>'''
 +
# '''REQUEST 55uA'''
 +
## (this is round 2 for this important run)
 +
## Try to take a good 12min run with minimal trips
 
# '''REQUEST 45uA'''
 
# '''REQUEST 45uA'''
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
Line 63: Line 71:
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
 
# '''REQUEST 15uA'''
 
# '''REQUEST 15uA'''
−
## Try to take a good 12min run with minimal trips
 
−
# '''REQUEST 5uA'''
 
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
 
# '''Repeat with only SHMS enabled'''
 
# '''Repeat with only SHMS enabled'''
Line 70: Line 76:
 
# '''Repeat with only HMS enabled'''
 
# '''Repeat with only HMS enabled'''
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
−
 
+
# '''REQUEST 5uA'''
−
=== 4 - 30uA Dummy ===
+
## '''Ensure both HMS and SHMS enabled again
−
# '''Change target to Al Dummy'''
 
−
# '''REQUEST 30uA'''
 
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
  
Line 81: Line 85:
  
 
Rotate HMS and change both HMS and SHMS current, and move in LH<sub>2</sub> target:
 
Rotate HMS and change both HMS and SHMS current, and move in LH<sub>2</sub> target:
 +
 +
'''BEAM OFF FOR SHMS MOMENTUM CHANGE'''
  
 
# ''P''<sub>HMS</sub> = -4.204 GeV/c ('''NEW''', pass through MOL)
 
# ''P''<sub>HMS</sub> = -4.204 GeV/c ('''NEW''', pass through MOL)
Line 89: Line 95:
 
=== 1 - LH<sub>2</sub> Scan ===
 
=== 1 - LH<sub>2</sub> Scan ===
 
# '''Change target to LH<sub>2</sub>'''
 
# '''Change target to LH<sub>2</sub>'''
−
# REQUEST 55uA
+
# '''REQUEST 55uA'''
 
## '''run at highest current available if we can't reach 55uA
 
## '''run at highest current available if we can't reach 55uA
 
## '''If running at 55uA: switch OFF SHMS DCs''': expecting ~1MHz SHMS singles rate which will trip the DCs
 
## '''If running at 55uA: switch OFF SHMS DCs''': expecting ~1MHz SHMS singles rate which will trip the DCs
 
### '''Else: keep DCs ON and carefully monitor if running at lower current''': ~40uA is the highest current we know we should be able to run without issues in this setting, but it is currently unknown at which exact current between 40uA-50uA the DCs start to trip.
 
### '''Else: keep DCs ON and carefully monitor if running at lower current''': ~40uA is the highest current we know we should be able to run without issues in this setting, but it is currently unknown at which exact current between 40uA-50uA the DCs start to trip.
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
−
# REQUEST 45uA
+
# '''REQUEST 45uA'''
 
## '''Ensure DCs are ON'''
 
## '''Ensure DCs are ON'''
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
−
# REQUEST 30uA
+
# '''REQUEST 30uA'''
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
−
# REQUEST 15uA
+
# '''REQUEST 15uA'''
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
−
# REQUEST 5uA
+
# '''REQUEST 5uA'''
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
  
−
=== 2 - C-1.5% Scan ===
+
=== 2 - 30uA Dummy ===
 +
# '''Change target to Al Dummy'''
 +
# '''REQUEST 30uA'''
 +
## Try to take a good 12min run with minimal trips
 +
 
 +
=== 3 - C-1.5% Scan ===
 
# '''Change target to C-1.5%'''
 
# '''Change target to C-1.5%'''
−
# REQUEST 55uA
+
# '''REQUEST 55uA'''
 
## run at highest current available if we can't reach 55uA
 
## run at highest current available if we can't reach 55uA
−
## '''Decide what to do with DCs''': should be able project from past runs what will happen
 
−
## '''If tripping is an issue, turn SHMS DCs OFF'''
 
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
−
# REQUEST 45uA
+
# '''REQUEST 45uA'''
−
## '''Decide what to do with DCs'''
 
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
−
## '''Ensure DCs are on'''
+
# '''REQUEST 30uA'''
−
# REQUEST 30uA
 
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
−
# REQUEST 15uA
+
# '''REQUEST 15uA'''
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
−
# REQUEST 5uA
+
# '''REQUEST 5uA'''
−
## Try to take a good 12min run with minimal trips
 
−
 
 
−
=== 3 - 30uA Dummy ===
 
−
# '''Change target to Al Dummy'''
 
−
# '''REQUEST 30uA'''
 
 
## Try to take a good 12min run with minimal trips
 
## Try to take a good 12min run with minimal trips
  
Line 135: Line 137:
 
# ''P''<sub>SHMS</sub> = 6.842 GeV/c ('''NEW''', pass through MOL)
 
# ''P''<sub>SHMS</sub> = 6.842 GeV/c ('''NEW''', pass through MOL)
 
# ''θ''<sub>SHMS</sub> = 6.49 deg (unchanged)
 
# ''θ''<sub>SHMS</sub> = 6.49 deg (unchanged)
 +
 +
* '''Reduce EDTM back to 10Hz'''
 +
* '''Set PS-5 back to 0''' (Else we won't be taking physics data!)
 +
* '''Set PS-1 to 13 or 14''' (Try to get close to 100Hz pre-scaled)
 +
* '''Set PS-3 to 5''' (Try to get close to 100Hz pre-scaled)
 +
* '''Ask for 50uA beam current (ensure SHMS raw singles rate below 700KHz!!!)'''
 +
* Resume taking 1h physics runs as usual

Latest revision as of 23:24, 15 October 2018

Goal

The electrons in the HMS will be used to monitor cryotarget boiling, while the positive polarity SHMS will be used to investigate the reliability of hadron tracking efficiencies at high rates. We will use three different targets:

  • standard 10cm LH2
  • C (z=1.5% RL) - maximum current 65uA
  • Al dummy - maximum current 40uA

Initial Setup

  1. Set PS1 and PS3 DAQ rates to 1.5kHz, to give a total rate to disk of about 3kHz.
  2. Increase EDTM trigger rate to 10kHz, to ensure that after prescaling there are 10k-100k EDTM events per run.
  3. Ensure the raster is on (2x2)

During scan

  1. Monitor number of EDTM events: to ensure 10k-100k events/run
  2. Try to get runs with minimum of beam trips: In particular, there might be a high number of trips due to the SHMS diffusor ion chambers at this small angle when running above 50uA. MCC can fix this by selectively changing the thresholds in the offending chambers. See here for more info. They should be aware of this.
  3. Be wary of DC HV trips in SHMS: we are at a small angle, for some of the higher currents we will have to switch off the HV for the SHMS DCs
  4. Use the highest current we can get: If MCC can't reach a current, we take data at the highest current that they can reach instead. This might mean we need to skip the some luminosity settings.

Sweep 1

0. Preparation

Rotate HMS to 12.50 degrees, everything else is unchanged.

  1. PHMS = -3.266 GeV/c (unchanged)
  2. θHMS = 12.50 deg (NEW)
  3. PSHMS = 6.842 GeV/c (unchanged)
  4. θSHMS = 6.49 deg (unchanged)

1 - 55uA LH2

  1. LH2 target (unchanged)
  2. Request 55uA; run at highest current available if we can't reach 55uA (likely)
  3. If running at 55uA: switch OFF SHMS DCs: expecting ~1MHz SHMS singles rate which will trip the DCs
    1. Else: keep DCs ON and carefully monitor if running at lower current: ~55uA is the highest current we know we should be able to run without issues in this setting, but it is currently unknown at which exact current between 55uA-60uA the DCs start to trip.
  4. Try to take a good 12min run with minimal trips

1b - Repeat above but with only SHMS enabled

1c - Repeat above but with only HMS enabled

2 - C-1.5% Scan

  1. Change target to C-1.5%
  2. REQUEST 55uA
    1. run at highest current available if we can't reach 55uA
    2. Ensure SHMS DCs are ON and carefully monitor
      1. If tripping is an issue, turn SHMS DCs OFF
    3. Try to take a good 12min run with minimal trips
  3. REQUEST 45uA
    1. Ensure SHMS DCs are ON
    2. Try to take a good 12min run with minimal trips
  4. REQUEST 30uA
    1. Try to take a good 12min run with minimal trips
  5. REQUEST 15uA
    1. Try to take a good 12min run with minimal trips
  6. REQUEST 5uA
    1. Try to take a good 12min run with minimal trips

3 - 30uA Dummy

  1. Change target to Al Dummy
  2. REQUEST 30uA
    1. Try to take a good 12min run with minimal trips

4. - LH2 Scan (con't)

  1. Change target to LH2
  2. REQUEST 55uA
    1. (this is round 2 for this important run)
    2. Try to take a good 12min run with minimal trips
  3. REQUEST 45uA
    1. Try to take a good 12min run with minimal trips
  4. REQUEST 30uA
    1. Try to take a good 12min run with minimal trips
  5. REQUEST 15uA
    1. Try to take a good 12min run with minimal trips
  6. Repeat with only SHMS enabled
    1. Try to take a good 12min run with minimal trips
  7. Repeat with only HMS enabled
    1. Try to take a good 12min run with minimal trips
  8. REQUEST 5uA
    1. Ensure both HMS and SHMS enabled again
    2. Try to take a good 12min run with minimal trips

Sweep 2

0. Preparation

Rotate HMS and change both HMS and SHMS current, and move in LH2 target:

BEAM OFF FOR SHMS MOMENTUM CHANGE

  1. PHMS = -4.204 GeV/c (NEW, pass through MOL)
  2. θHMS = 14.91 deg (NEW)
  3. PSHMS = 6.053 GeV/c (NEW)
  4. θSHMS = 6.49 deg (unchanged)

1 - LH2 Scan

  1. Change target to LH2
  2. REQUEST 55uA
    1. run at highest current available if we can't reach 55uA
    2. If running at 55uA: switch OFF SHMS DCs: expecting ~1MHz SHMS singles rate which will trip the DCs
      1. Else: keep DCs ON and carefully monitor if running at lower current: ~40uA is the highest current we know we should be able to run without issues in this setting, but it is currently unknown at which exact current between 40uA-50uA the DCs start to trip.
    3. Try to take a good 12min run with minimal trips
  3. REQUEST 45uA
    1. Ensure DCs are ON
    2. Try to take a good 12min run with minimal trips
  4. REQUEST 30uA
    1. Try to take a good 12min run with minimal trips
  5. REQUEST 15uA
    1. Try to take a good 12min run with minimal trips
  6. REQUEST 5uA
    1. Try to take a good 12min run with minimal trips

2 - 30uA Dummy

  1. Change target to Al Dummy
  2. REQUEST 30uA
    1. Try to take a good 12min run with minimal trips

3 - C-1.5% Scan

  1. Change target to C-1.5%
  2. REQUEST 55uA
    1. run at highest current available if we can't reach 55uA
    2. Try to take a good 12min run with minimal trips
  3. REQUEST 45uA
    1. Try to take a good 12min run with minimal trips
  4. REQUEST 30uA
    1. Try to take a good 12min run with minimal trips
  5. REQUEST 15uA
    1. Try to take a good 12min run with minimal trips
  6. REQUEST 5uA
    1. Try to take a good 12min run with minimal trips

Aftermath

Return spectrometers to production settings. Rotate HMS and change both HMS and SHMS current, and move in LH2 target:

  1. PHMS = -3.266 GeV/c (NEW)
  2. θHMS = 23.00 deg (NEW)
  3. PSHMS = 6.842 GeV/c (NEW, pass through MOL)
  4. θSHMS = 6.49 deg (unchanged)
  • Reduce EDTM back to 10Hz
  • Set PS-5 back to 0 (Else we won't be taking physics data!)
  • Set PS-1 to 13 or 14 (Try to get close to 100Hz pre-scaled)
  • Set PS-3 to 5 (Try to get close to 100Hz pre-scaled)
  • Ask for 50uA beam current (ensure SHMS raw singles rate below 700KHz!!!)
  • Resume taking 1h physics runs as usual
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