This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision Next revision Both sides next revision | ||
tuning_the_s800_xdt [2015/10/26 12:00] pereira [Timing setup] |
tuning_the_s800_xdt [2015/10/26 14:01] pereira |
||
---|---|---|---|
Line 161: | Line 161: | ||
At present, there are three electronic " | At present, there are three electronic " | ||
- | * Although the ToF reference (" | ||
- | * Before going to the ToF modules, the OBJ and XFP signals are sent to a CANBERRA CFD 454 CFD in data U6 from the data-U6 patch panel (OBJ: patch panel #54, XFP: patch panel #1). (The exception is the OBJ signal into the MTDC) | ||
- | * MTDC: | ||
- | * Before getting into the MTDC, the OBJ, XFP, and E1 up signals in the MTDC go through a Mesytec MCFD | ||
- | * The OBJ signal into the MCFD comes directly from the detector via S3 patch panel #94 (i.e., there is no signal to check in data U6) | ||
- | * The XFP signal into the MCFD module comes from data-U6 patch panel #70, connected to the CANBERRA 454 CFD XFP output | ||
- | * SpecTcl calculates the OBJ-to-Focal-Plane and XFP-to-Focal-Plane ToFs by substracting the E1 up time (MTDC channel 15) to the OBJ time (MTDC channel 3) and the XFP time (MTDC channel 2) | ||
- | * The MTDC timing signals do not require external delay adjustments because the matching window is sufficiently wide | ||
- | * Tennelec TACs: | ||
- | * The OBJ **stop** signal to the " | ||
- | * The XFP **stop** signal to the " | ||
- | * Phillips TDC: | + | * Select SpecTcl window **S800_TOF.win** |
- | * The OBJ output signal from the CANBERRA 454 CFD is delayed with the low-noise delay boxes in data-U6, and sent to the TDC via patch panel #67 | + | * The three columns correspond to the **RF-FP** ToF (left), **OBJ-FP** (center), and **XFP-FP** (right) |
- | * The XFP output signal from the CANBERRA 454 CFD is delayed | + | * The first (top) row corresponds |
- | * SpecTcl calculates | + | * The second row corresponds to the MTDC with all the hits included |
+ | * The third row corresponds | ||
+ | * The fourth row corresponds to the ORTEC TACs. Note that there is not **RF-FP TAC** | ||
+ | * The two spectra in the fifth row corresponds | ||
+ | * 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 TDC start is sent from the ULM trigger module. Since the delay of the S800 trigger may be adjusted during XDT, the stop signals (e.g. from OBJ or XFP) will need to be re-adjusted. | + | {{: |
- | | + | |
- | * There are 4 TDC inspect channels | + | * Using the [[S800 DAQ tools# |
- | * The full range of the TDC is 400 ns | + | * Select the timing signals (Delay |
- | * Set each timing | + | * Adjust |
- | * TDCs of last 4 listed signals (including XF and object scintillators) are bypassed with cable delays inside | + | * Adjust |
- | * They can be inspected, however using the GUI | + | * In principle, the TACs delays don't need to be adjusted |
+ | ==== Checking Particle ID and rate at S800 FP ==== | ||
- | | + | * Select SpecTcl window **S800_PID.win** in directory **/ |
+ | | ||
+ | * The first (top) row corresponds to the Phillips | ||
+ | * The second row corresponds to the MTDC with just the first hit included | ||
+ | * The third row corresponds to the ORTEC TACs. Note that there is not **RF-FP TAC** | ||
+ | * You might need to adjust the limits of the spectra | ||
- | * Trigger the scope with the “Live Trigger” signal patched to data-U6 | + | {{: |
- | * There are 4 trigger inspect channels patched to data-U6 that can be assigned using the trigger GUI | + | |
- | * Examine the timing of each of the selectable listed signals with respect to the “Live Trigger” signal | ||
- | * There are 4 TDC inspect channels patched to data-U6 that can be assigned using the trigger GUI | ||
- | * The full range of the TDC is 400 ns | ||
- | * Set each timing to 200 ns | ||
- | * TDCs of last 4 listed signals (including XF and object scintillators) are bypassed with cable delays inside the vault and thus their delays cannot be controlled with the GUI | ||
- | * They can be inspected, however using the GUI | ||
+ | * Establish PID and measure rate | ||
+ | * Determine the blob that corresponds to the unreacted beam (refer to information on setting from A1900 FP) | ||
+ | * Take gates around the fragment of interest | ||
+ | * Measure the beam intensity the appropriate faraday cup | ||
+ | * Take a run on disk | ||
+ | * Measure the beam intensity again and calculate the average value | ||
+ | * In **[[s800 SpecTcl|SpecTcl GUI]], click **Attach to File** and select data file **run-xxxx-xx.evt** in directory **/ | ||
+ | * Check the run time and live time from the corresponding scaler file in directory **/ | ||
+ | * Calculate the rate and purity and compare with the value in the A1900 FP to determine the transmission | ||
- | * See [[http:// | ||
- | * The TDC delays can only be changed when the run control is stopped; must SAVE settings before starting run control not to overwrite adjustments being made | ||
- | * The “S800” trigger is from E1 up signal | ||
- | * Trigger the scope with the “Live Trigger” signal patched to data-U6 | ||
- | * There are 4 trigger inspect channels patched to data-U6 that can be assigned using the trigger GUI | ||
- | * Examine the timing of each of the selectable listed signals with respect to the “Live Trigger” signal | ||
- | * There are 4 TDC inspect channels patched to data-U6 that can be assigned using the trigger GUI | ||
- | * The full range of the TDC is 400 ns | ||
- | * Set each timing to 200 ns | ||
- | * TDCs of last 4 listed signals (including XF and object scintillators) are bypassed with cable delays inside the vault and thus their delays cannot be controlled with the GUI | ||
- | * They can be inspected, however using the GUI | ||
- | * Information | ||
- | * The signal delays controlled by the GUI (and not by cable delays) are not “pipelined” -– i.e., any new signals that arrive during the delay time of a previous signal are lost and thus deadtime is introduced into the system. | ||
- | * All of the trigger signals are not pipelined and are thus subject to deadtime | ||
- | ==== Checking Particle ID and rate at S800 FP ==== | ||
- | * Establish PID | ||
- | * Refer to information on setting from A1900 FP | ||
- | * dE-TOF | ||
- | * dE signal from Ion Chamber | ||
- | * TOF from XF or Object scintillator to S800 FP | ||
- | * Not necessary to implement dE- or TOF-based corrections | ||
- | * Document rate of fragment of interest with run to disk | ||
- | * Measure beam current with appropriate Faraday cups | ||
- | * Timed run | ||
==== Analysis line classic PPAC setup (Focus optics only) ==== | ==== Analysis line classic PPAC setup (Focus optics only) ==== | ||
+ | |||
* " | * " | ||
* Classic PPACs have rate limitations from pileups | * Classic PPACs have rate limitations from pileups | ||
Line 258: | Line 237: | ||
==== Setup beamline ==== | ==== Setup beamline ==== | ||
+ | |||
* Object and XF scintillators and intermediate image PPACs inserted if they will be used | * Object and XF scintillators and intermediate image PPACs inserted if they will be used | ||
* If Object scintillator will not be used, there is no reason to look at beam on it unless to debug a problem with the transmission | * If Object scintillator will not be used, there is no reason to look at beam on it unless to debug a problem with the transmission | ||
* Set spectrograph Brho for unreacted fragment | * Set spectrograph Brho for unreacted fragment | ||
+ | |||
==== Start scalers ==== | ==== Start scalers ==== | ||
+ | |||
* Use s800 account | * Use s800 account | ||
Line 280: | Line 262: | ||
=== Focused optics === | === Focused optics === | ||
+ | |||
* Expectations for A1900 FP to S800 FP transmission | * Expectations for A1900 FP to S800 FP transmission | ||
* 80% or better for mid-Z fragments | * 80% or better for mid-Z fragments | ||
Line 295: | Line 278: | ||
=== Matched optics === | === Matched optics === | ||
+ | |||
* Typically much more time is invested for optimizing optics for matched optics than for focused optics | * Typically much more time is invested for optimizing optics for matched optics than for focused optics | ||
Line 309: | Line 293: | ||
==== Setting up Reaction Settings ==== | ==== Setting up Reaction Settings ==== | ||
+ | |||
* Calculating reaction setting | * Calculating reaction setting | ||
* Center unreacted beam at S800 FP | * Center unreacted beam at S800 FP | ||
Line 333: | Line 318: | ||
==== Coincidences ==== | ==== Coincidences ==== | ||
+ | |||
* Overview | * Overview | ||
* Most experiments at the S800 involve setting up an auxiliary detector system (e.g. SeGA, HiRA, etc) to be used in coincidence with the standard detectors of the S800. | * Most experiments at the S800 involve setting up an auxiliary detector system (e.g. SeGA, HiRA, etc) to be used in coincidence with the standard detectors of the S800. | ||
Line 418: | Line 404: | ||
====== Dispersion Matching tuning ====== | ====== Dispersion Matching tuning ====== | ||
+ | |||
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, | ||