momentum aperture bug for linacs

Moderators: michael_borland, soliday

Post Reply
michael_borland
Posts: 1927
Joined: 19 May 2008, 09:33
Location: Argonne National Laboratory
Contact:

momentum aperture bug for linacs

Post by michael_borland » 27 Aug 2011, 13:34

A bug was reported by Norio Nakamura (KEK) for the momentum_aperture command. Basically, if acceleration or deceleration is involved (e.g., RFCA with CHANGE_P0=1), the results are incorrect. It is unclear right now when this bug was introduced.

A workaround is to insert ENERGY elements to force the central momentum to the correct, fixed values.

For those who build from source, the corrected code is attached. This will appear in the next release in a few weeks.

--Michael
Attachments
momentumAperture.c
(30.48 KiB) Downloaded 1333 times

michael_borland
Posts: 1927
Joined: 19 May 2008, 09:33
Location: Argonne National Laboratory
Contact:

Re: momentum aperture bug for linacs

Post by michael_borland » 29 Aug 2011, 08:57

I found a similar bug in the Touschek scattering simulation for linacs. Corrected code is attached.

--Michael
Attachments
touschekScatter.c
(45.08 KiB) Downloaded 1367 times

michael_borland
Posts: 1927
Joined: 19 May 2008, 09:33
Location: Argonne National Laboratory
Contact:

Re: momentum aperture bug for linacs

Post by michael_borland » 29 Aug 2011, 17:22

michael_borland wrote:I found a similar bug in the Touschek scattering simulation for linacs. Corrected code is attached.

--Michael
Actually, this wasn't so much a bug as a missing feature in the released version.

--Michael

michael_borland
Posts: 1927
Joined: 19 May 2008, 09:33
Location: Argonne National Laboratory
Contact:

Re: momentum aperture bug for linacs

Post by michael_borland » 07 Sep 2011, 14:30

These bugs are fixed in version 24.1.

--Michael

Post Reply