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tuning_the_s800_xdt [2015/10/27 14:20]
pereira [Setting up Reaction Settings]
tuning_the_s800_xdt [2016/03/13 16:18]
pereira [FP scintillator setup]
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       * Expected "open" values for top and bottom slits are CT ~6.8 and CB ~3.2, respectively        * Expected "open" values for top and bottom slits are CT ~6.8 and CB ~3.2, respectively 
  
-  * Ensure that CRAD04 (typically connected to object scintillator) is enabled with a rate limit of **20 kHz** (CRAD04 looks at E1 up FP scintillator)+  * Ensure that CRAD04 is enabled with a rate limit of **20 kHz** (CRAD04 looks at E1 up FP scintillator)
  
   * Remember: S800 FP rate limit is **6 kHz**   * Remember: S800 FP rate limit is **6 kHz**
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           * End and Begin **[[s800 daq tools#Run Control Window|ReadoutGUI]]** to assert new trigger condition           * End and Begin **[[s800 daq tools#Run Control Window|ReadoutGUI]]** to assert new trigger condition
  
-  * Select **[[s800 SpecTcl|Spectcl]]** window **S800_SCINT.win**+  * Select **[[s800 SpecTcl|Spectcl]]** window **S800_SCINT.win** in directory **/user/s800/operations/spectcl/s800v7/Windows**. NOTE: Spectra definition files can be found in directory **/user/s800/operations/spectcl/s800v7/Definitions**. A good file with useful spectra is **s800xdt.tcl** 
  
   * Adjust **[[hv bias|bias]]** looking at 2D spectra **e1.deup_e1.dedown** (showing the parameters s800.fp.e1.de_down vs. s800.fp.e1.de_up) for the FP E1 scintillator   * Adjust **[[hv bias|bias]]** looking at 2D spectra **e1.deup_e1.dedown** (showing the parameters s800.fp.e1.de_down vs. s800.fp.e1.de_up) for the FP E1 scintillator
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-  * Select **[[s800 SpecTcl|Spectcl]]** window **S800_IC.win**+  * Select **[[s800 SpecTcl|Spectcl]]** window **S800_IC.win** 
  
   * Adjust pad gains   * Adjust pad gains
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           * They correspond to the non-dispersive position of the beam in the CRDCs.            * They correspond to the non-dispersive position of the beam in the CRDCs. 
  
-{{:wiki:CRDCS-example.png?850|CRDCs summary spectra}}+{{:wiki:CRDCS-example.png?850|S800_CRDCS.win SpecTcl window}}
  
  
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       * The three columns correspond to the **RF-FP** ToF (left), **OBJ-FP** (center), and **XFP-FP** (right)       * The three columns correspond to the **RF-FP** ToF (left), **OBJ-FP** (center), and **XFP-FP** (right)
       * The first (top) row corresponds to the Phillips TDC       * The first (top) row corresponds to the Phillips TDC
-      * The second row corresponds to the MTDC with all the hits included+      * The second row corresponds to the MTDC with all the hits included. Note that in a unreacted-beam setting, the first hit typically provides the "good" ToF (i.e. start and stop signals come from the same event) 
       * The third row corresponds to the MTDC with only the first hit       * The third row corresponds to the MTDC with only the first hit
       * The fourth row corresponds to the ORTEC TACs. Note that there is not **RF-FP TAC**       * The fourth row corresponds to the ORTEC TACs. Note that there is not **RF-FP TAC**
-      * The two spectra in the fifth row corresponds to the MTDC summary spectra of OBJ-FP and XFP-FP ToFs (zoomed in). The spectra show the ToF (vertical axis) vs. hit number (horizontal axis). In an unreacted setting, one expects to see the most of the "good" ToF peak recorded in the first hit+      * The two spectra in the fifth row corresponds to the MTDC summary spectra of OBJ-FP and XFP-FP ToFs (zoomed in). The spectra show the ToF (vertical axis) vs. hit number (horizontal axis). Note that in a unreacted-beam setting, the first hit typically provides the "good" ToF (i.e. start and stop signals come from the same event). This is not the case in a reaction setting, where the rates in the XFP and OBJ detectors are much higher than in the FP SCI 
       * An empty ToF spectrum means that either the delays are not right (and need to be adjusted) or the spectrum range is too narrow        * An empty ToF spectrum means that either the delays are not right (and need to be adjusted) or the spectrum range is too narrow 
       * The MTDC spectra should never be empty because the matching window is sufficiently wide (around 4000 ns)       * The MTDC spectra should never be empty because the matching window is sufficiently wide (around 4000 ns)
  
 {{:wiki:SpecTcl-e14019-run103.jpg?850|S800_ToF.win page}} {{:wiki:SpecTcl-e14019-run103.jpg?850|S800_ToF.win page}}
 +
 +  * Due to the multi-hit capability of the MTDC, we need to select the "good" MTDC ToF peak so that SpecTcl can search for the right hit (more details can be found [[Timing#MTDC|here]]):
 +      * Use the spectra **TOF.MTDC_RF**, **TOF.MTDC_OBJ**, and **TOF.MTDC_XFP** (second row in figure above) 
 +      * Using the cursor mouse, check the lower and higher limits defining the region in the MTDC ToF spectra with the "good" ToF peak. Do it for the three ToFs: RF-FP, OBJ-FP, and XFP-FP
 +      * Go to the **Variables** page in SpecTcl GUI and assign the limits to the following variables: 
 +              * **s800.fp.vmetdc.mtdc_objlow** and **s800.fp.vmetdc.mtdc_rfhigh** for RF-XFP
 +              * **s800.fp.vmetdc.mtdc_objlow** and **s800.fp.vmetdc.mtdc_rfhigh** for OBJ-XFP
 +              * **s800.fp.vmetdc.mtdc_xfplow** and **s800.fp.vmetdc.mtdc_xfphigh** for XFP-XFP
 +      * For each ToF, SpecTcl will search the hit number that fits in the selected region. The new MTDC ToF parameters are **s800.fp.vmetdc.mtdc_rf**, **s800.fp.vmetdc.mtdc_obj**, and **s800.fp.vmetdc.mtdc_xfp** 
  
   * If necessary, adjust delays:   * If necessary, adjust delays:
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       * Adjust the TDC delays of E1 up, down using the Delay GUI       * Adjust the TDC delays of E1 up, down using the Delay GUI
       * In principle, the TACs delays don't need to be adjusted       * In principle, the TACs delays don't need to be adjusted
 +
 +
 +  * Check the efficiencies of the Phillips TDC, TACs, and MTDC for the OBJ-FP and XFP-FP ToFs:
 +      * Make a gate on spectrum **IC.SUM** selecting the region of interest, and call it "IC"
 +      * Looking at the ToF spectra gated on "IC" compare the recorded events in the spectra with the number of events in the gate
 +      * The window file **S800_TOF_EFFICIENCY.win** includes all the spectra needed
  
  
 ==== Checking Particle ID and rate at S800 FP ==== ==== Checking Particle ID and rate at S800 FP ====
  
-  * Select SpecTcl window **S800_PID.win** in directory **/user/s800/operations/spectcl/Windows** +  * Select SpecTcl window **S800_PID.win** 
       * The three columns correspond to the PID determined with the **RF-FP** ToF (left), **OBJ-FP** (center), and **XFP-FP** (right)       * The three columns correspond to the PID determined with the **RF-FP** ToF (left), **OBJ-FP** (center), and **XFP-FP** (right)
-      * The first (top) row corresponds to the Phillips TDC +      * The first (top) row corresponds to PID spectra using the Phillips TDC 
-      * The second row corresponds to the MTDC with just the first hit included +      * The second row corresponds to PID spectra using the MTDC with __just the first hit included__ 
-      * The third row corresponds to the ORTEC TACs. Note that there is not **RF-FP TAC**+      * The third row corresponds to PID spectra using the MTDC including the correct hit corresponding to the good ToF peak (see previous section) 
 +      * The fourth row corresponds to PID spectra using the MTDC gated on the "good" ToF peak   
 +      * The fifth row corresponds to PID spectra using the ORTEC TACs. Note that there is not **RF-FP TAC**
       * You might need to adjust the limits of the spectra to get a good resolution       * You might need to adjust the limits of the spectra to get a good resolution
  
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   * Establish PID and measure rate   * Establish PID and measure rate
-      * Determine the blob that corresponds to the unreacted beam (refer to information on setting from A1900 FP)+      * Choose your favorite PID spectrum and determine the blob that corresponds to the unreacted beam (refer to information on setting from A1900 FP). Note: the PID using the first MTDC hit might be missing good events
       * Take gates around the fragment of interest       * Take gates around the fragment of interest
       * Measure the beam intensity the appropriate faraday cup       * Measure the beam intensity the appropriate faraday cup
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   * Reaction setting to FP    * Reaction setting to FP 
       * Start with Attenuator setting of unreacted beam and step up in intensity       * Start with Attenuator setting of unreacted beam and step up in intensity
-      * Set up beam blocker (labeled I255 Slitsin the S3 page of Barney, if necessary+      * If necessary, set up beam blocker looking at **CRDC1.RAWS** and/or **CRDC2.RAWS** SpecTcl spectra (see **S800_CRDCS.win** SpecTcl window shown above)  
 +          * Click on label **I255 Slits** in the S3 page of Barney
           * Expected "open" values for top and bottom slits are CT ~6.8 and CB ~3.2, respectively            * Expected "open" values for top and bottom slits are CT ~6.8 and CB ~3.2, respectively 
           * Expect to see unreacted beam if reaction setting is within +/- 3% of unreacted beam setting           * Expect to see unreacted beam if reaction setting is within +/- 3% of unreacted beam setting
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               * What experimenters want (e.g., if they want singles, the cut has to be more restrictive to limit acquisition deadtime)               * What experimenters want (e.g., if they want singles, the cut has to be more restrictive to limit acquisition deadtime)
           * Move blocker, decrease attenuator, repeat           * Move blocker, decrease attenuator, repeat
 +
 +      * If necessary, do the ToF corrections to improve the PID resolution (instructions [[During experiments#Particle identification corrections|here]])
  
  
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- 
- 
-====== Follow-up ====== 
- 
-  * Before leaving beam with experimenters 
-      * Set up current trip points on Linux HV controls 
-          * Values used for K-48 
-              * 5 for CRDC and Ion Chamber anodes and intermediate image ppacs 
-              * 50 for CRDC drifts 
-              * 80 for IC drift 
-          * Ensure alarms are running 
-              * Make sure Linux HV GUI alarms are enabled 
-              * Make sure threshold on isobutane level is set up (not currently connected to alarms because they give too many false alarms when communication is lost) 
-          * All logs are being recorded 
-              * There is no log file for biases controlled by Labview 
-              * Linux HV 
-              * LabView gas handling system 
-              * Note in logbook 
-                  * Scintillator biases 
-                  * IC gate biases 
-          * Post reference printouts for experimenters 
-              * HV status: a snapshot of HV GUI 
-              * Gas handling system status: a snapshot of LabView window 
- 
-  * Create window configuration with summing regions to make it easier for experimenters to track efficiency/performance of all detectors 
- 
-  * Setting up coincidences for additional reaction settings in an experiment 
-      * Do not need to redo coincidence settup if secondary beam does not change 
-      * Might need to redo coincidence setup if secondary beam changes drastically 
- 
-  * To watch during experiment 
-      * Look for isobutene running out – messes up data over several hours 
- 
-  * Implementing dE- or TOF-based corrections is part of EXR  
- 
-More detail needed 
- Minimum rates required for coincidence setup 
- Selection of appropriate substitute reactions for coincidence setup 
- How to feel comfortable that there will not be a problem with FP detector gases running out 
- Starting alarms 
- Starting logging 
  
  
  
tuning_the_s800_xdt.txt · Last modified: 2023/09/22 15:15 by swartzj