Differences

This shows you the differences between two versions of the page.

--- task:k500_generaltuning [2025/07/08 10:38] – lange
+++ task:k500_generaltuning [2025/07/08 11:05] (current) – lange
@@ Line 3: / Line 3: @@
 For the most part, all devices may be tuned to maximize the beam transmission. There are only a handful of devices that we don't tune: dee phases and trim coils (besides bumps). There are however devices that are more common to tune.
-== Standard K500 Tuning Devices ==
+=== Standard K500 Tuning Devices ===
 For a normal, quick tuneup of the k500, tune the following while sending beam to FC2007:
   * Dee voltages K5DVR_A/B/C
@@ Line 13: / Line 13: @@
 It is often useful to go through these devices multiple times since the effects of many devices are interrelated.
-== Injection Line Tuning ==
+=== Injection Line Tuning ===
-It is best the tune the injection line devices on accelerated beam, either on FC2007 or on the main probe inside the machine. In this configuration, you may be sure that the beam you are measuring is the correct one and not an analog. You will also be optimizing the beam for injection/extraction into the K500, rather than just beam transport to the end of the injection line. At this point, all devices may be tuned. Suggest to start with correctors, then focusing elements. Iteration is necessary. If time permits, it may help to quad center. This must be done using viewers.
+It is best the tune the injection line devices on accelerated beam, either on FC2007 or on the main probe inside the machine. In this configuration, you may be sure that the beam you are measuring is the correct one and not an analog. You will also be optimizing the beam for injection/extraction into the K500, rather than just beam transport to the end of the injection line. At this point, all devices may be tuned. Suggest to start with correctors, then focusing elements. Iteration is necessary. If time permits, it may help to quad center. This must be done using viewers. It is important to send beam into the k500 to see if the changes actually helped injection efficiency.
+=== Extraction Tuning ===
+Tuning the k500 extraction is best done during initial beam setup. It is not a short term tuning activity, and is not the first thing to try when restoring a saveset. During this process extraction drive positions for the deflectors E1 and E2, mag channels M1-M8, and compensating bars C1 and C2, as well as deflector voltages should all be adjusted. These devices should be changed in conjunction with adjustments to the main field and the bumps/dees. The primary goal is to improve transmission into the extraction channel and from there to the faraday cup FC2007. While doing this, minimize the beam current lost on the main probe scraper jfjfjfjf and the m-channels MGCH-ALL. Some pitfalls to be aware of:
+  * Some m-channels may be intentionally out of the beam path. M3, M4N and M4W, and M7N and M7W may be out. Check the beam calculations and/or look at their positions compared to drives up/downstream.
+  * Moving the m-channels can move the beam position at D2007. It is necessary to check the viewer to see if the beam is centered. If the beam is near the edge of the faraday cup, it will read high but this is artificially inflated.
+  * The beamspot shape may change. This could affect transmission to SEE.
+=== HEBT Tuning ===
+From limited experience, here are a few suggestions for adjusting the HEBT
+  * Begin from scaled focusing elements and these may be close to what is needed.
+  * Quad centering in the first HEBT section may be productive. Do this on the viewer D???? and the stub faraday cup.
+  * Adjust the dipoles to maximize beam current to FC2192 and/or center on viewer D2191. The correctors after the dipoles should be able to be set to 0.
+  * With small beam optics, you may need to adjust the 1st four quads to maximize transmission. The beam size out of the cyclotron may be different.