Conference Room SAD


[Thread display] [Reply] [New arrival display] [Word search] [Notes] [管理用]

No. 1134
Title SAD beam-pipe aperture for SuperKEKB
Date : 2020/03/19(Thu) 14:42:39
Name Andrii Natochii   <natochii@hawaii.edu>
URL
Dear all,
May I ask you about particle tracking for the beam background study at the SuperKEKB:
We define beam-pipe aperture for each ring (LER/HER) as the following:

==============================================================================================
==============================================================================================
(* Set aperture *)
(* global aperture setting *)
Scan[(LINE["AX",#]=0.045;LINE["AY",#]=0.045;LINE["DX",#]=Twiss["DX",#];LINE["DY",#]=Twiss["DY",#];)&,LINE["NAME","AP.*"]];
(* ZVQLC3RP: 26.23m upstream, ZVQLC3LP: 27.50m downstram from IP *)
Scan[(LINE["AX",#]=0.040;LINE["AY",#]=0.040;LINE["DX",#]=Twiss["DX",#];LINE["DY",#]=Twiss["DY",#];)&,
Select[LINE["NAME","AP.*"],(LINE["POSITION","ZVQLC3RP"]<LINE["POSITION",#]<LINE["POSITION","ZVQLC3LP"])&]];
==============================================================================================
==============================================================================================

Here we use twiss parameters DX/DY for the center of the aperture ellipse. Do you know why?
As I understand, it must be 0. Because we need to apply aperture with respect to the design orbit which seats at DX=0 DY=0. Isn’t it? As far as I know Twiss[“DX”] returns an offset between design and closed orbits.
Thanks in advance.

Best regards,
Andrii

- Related List tree (Click ▼ to display all articles in a thread.)


- Reply Form (Reply to the above using the following.)
Name
E-Mail
Subject
Message
URL
Password (alphanumeric characters within 8)
Subscribe Key (Enter the number of the right image) Post key


- Modify or delete a contributeted article using the following form. -
Do No Password

- WebForum -