tuning_the_s800_xdt
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tuning_the_s800_xdt [2015/10/26 14:18] pereira [Setting Optimization] |
tuning_the_s800_xdt [2015/10/30 10:25] pereira [Setting up Reaction Settings] |
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| * Expected " | * Expected " | ||
| - | * Ensure that CRAD04 | + | * 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** | ||
| Line 55: | Line 55: | ||
| * Adjust MCFD threshold: | * Adjust MCFD threshold: | ||
| - | * Open configuration file **MCFD16.tcl** in **/user/s800/ | + | * Using the [[s800 daq tools# |
| * The OBJ signal feeding this module is not patched out to data U6 | * The OBJ signal feeding this module is not patched out to data U6 | ||
| - | * The OBJ signal from MCFD-16 module goes to the Mesytec | + | * The OBJ signal from MCFD module goes to the Mesytec |
| * Make sure that the threshold of the XFP MCFD channel is reasonable. Rates in scaler channels XFP.Scint and XFP.MCFD.Scint should be comparable | * Make sure that the threshold of the XFP MCFD channel is reasonable. Rates in scaler channels XFP.Scint and XFP.MCFD.Scint should be comparable | ||
| * Adjust MCFD OBJ threshold looking at scalers. The ratio of OBJ to XFP scaler rates (channels OBJ.MCFD.Scint and XFP.MCFD.Scint) should reflect the transmission of the cocktail beam | * Adjust MCFD OBJ threshold looking at scalers. The ratio of OBJ to XFP scaler rates (channels OBJ.MCFD.Scint and XFP.MCFD.Scint) should reflect the transmission of the cocktail beam | ||
| Line 74: | Line 74: | ||
| * 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 **/ |
| * 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 | ||
| Line 94: | Line 94: | ||
| - | * Select **[[s800 SpecTcl|Spectcl]]** window **S800_IC.win** | + | * Select **[[s800 SpecTcl|Spectcl]]** window **S800_IC.win** |
| * Adjust pad gains | * Adjust pad gains | ||
| Line 155: | Line 155: | ||
| * 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. | ||
| - | {{: | + | {{: |
| Line 165: | Line 165: | ||
| * 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 " |
| * 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). | + | * 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). |
| * 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) | ||
| {{: | {{: | ||
| + | |||
| + | * Due to the multi-hit capability of the MTDC, we need to select the " | ||
| + | * Use the spectra **TOF.MTDC_RF**, | ||
| + | * Using the cursor mouse, check the lower and higher limits defining the region in the MTDC ToF spectra with the " | ||
| + | * 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**, | ||
| * If necessary, adjust delays: | * If necessary, adjust delays: | ||
| Line 180: | Line 189: | ||
| * 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 " | ||
| + | * Looking at the ToF spectra gated on " | ||
| + | * 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 **/ | + | * 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 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 " | ||
| + | * 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 | ||
| Line 195: | Line 212: | ||
| * Establish PID and measure rate | * Establish PID and measure rate | ||
| - | * Determine | + | * Choose your favorite PID spectrum and determine |
| * 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 | ||
| Line 258: | Line 275: | ||
| - | ====== Dispersion Matching | + | ====== Dispersion Matching |
| In the dispersion-matching optics, the S800 focal point is achromatic, i.e. the position of the beam in the dispersive direction does not depend on the momentum. As a consequence, | In the dispersion-matching optics, the S800 focal point is achromatic, i.e. the position of the beam in the dispersive direction does not depend on the momentum. As a consequence, | ||
| Line 286: | Line 303: | ||
| | | ||
| * The leftmost peak corresponds to reactions with H. The central peak are reaction with C. The goal of the tweak is to make these peaks as narrow as possible | * The leftmost peak corresponds to reactions with H. The central peak are reaction with C. The goal of the tweak is to make these peaks as narrow as possible | ||
| - | * Open the NCS application **QtKM** in the Applications Menu. Open file **BLSetup_A1900.gkm**. The magnetic elements that are typically tweaked with the knob box seating | + | * Open the NCS application **QtKM** in the Applications Menu. Open file **BLSetup_A1900.gkm**. The magnetic elements that are typically tweaked with the knob box sitting |
| | | ||
| * The two figures below show the spectrum **CRDC1.XG!FOI-AFP-BFP** before (top) and after (bottom) the dispersion-matching tuning for a typical experiment. Be aware that the width given by SpecTcl for the selected peak is not too reliable. It is more convenient to do a real gaussian fit. Unfortunatelly this is not an option included in the current version of SpecTcl. That's why some device physicists prefer SpecTk for this type of tuning | * The two figures below show the spectrum **CRDC1.XG!FOI-AFP-BFP** before (top) and after (bottom) the dispersion-matching tuning for a typical experiment. Be aware that the width given by SpecTcl for the selected peak is not too reliable. It is more convenient to do a real gaussian fit. Unfortunatelly this is not an option included in the current version of SpecTcl. That's why some device physicists prefer SpecTk for this type of tuning | ||
| Line 310: | Line 327: | ||
| * 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, | + | * If necessary, set up beam blocker |
| + | * Click on label **I255 Slits** in the S3 page of Barney | ||
| + | * Expected " | ||
| * 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 | ||
| * Should have to move only one of the two blockers unless charge states are present | * Should have to move only one of the two blockers unless charge states are present | ||
| - | * A graphic tool is available to help (not yet calibrated) | ||
| * Try to cut only as much as necessary; depends on | * Try to cut only as much as necessary; depends on | ||
| * What rate limits allow | * What rate limits allow | ||
| * 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# | ||
| Line 333: | Line 353: | ||
| * Probably smaller typical S800 delay needed for HiRA | * Probably smaller typical S800 delay needed for HiRA | ||
| * An example of experiments where auxiliary detectors are not used and, thus, setting up coincidence timing is not an issue are the experiments with tritons run by the charge exchange group | * An example of experiments where auxiliary detectors are not used and, thus, setting up coincidence timing is not an issue are the experiments with tritons run by the charge exchange group | ||
| - | * It is not clear whether coincidence setup gets logged as “XDT” or “EXR” | + | |
| * Choice of setting to be used for coincidence timing setup | * Choice of setting to be used for coincidence timing setup | ||
| * The reaction of interest for the experiment can be used to setup coincidences only if the rate of coincidences is high enough | * The reaction of interest for the experiment can be used to setup coincidences only if the rate of coincidences is high enough | ||
| Line 367: | Line 386: | ||
| - | |||
| - | |||
| - | ====== 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/ | ||
| - | |||
| - | * 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
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