The OPAL Discussion Forum

["Adelmann Andreas (PSI)" <andreas.adelmann AT psi.ch>]

Dear James, 

I've read through what the user manual has to say a few times and
believe it should be possible to specify mid-plane fields along with
3D RF using the BANDRF type, and an additional HDF5 input file.

Yes this is correct!

I cc: Hui, he is using this format (if I am not mistaken) and can give you better input on this.

I also opened an issue (BABDRF) please contribute. 

Cheers Andreas 

PS: please use next time opal AT lists.psi.ch.

On 9 Mar 2017, at 10:00, Chris Rogers <chris.rogers AT stfc.ac.uk> wrote:

Hi James,
I am not familiar with the BANDRF model. Andreas (cc) might be able to help. Just as a warning, if you would like to use the BANDRF together with SBEND3D, it will need a bit of jiggling in the code...

Cheers,
Chris


On 08/03/17 17:16, James Gerity wrote:

Chris,
 Sorry for the long radio silence on this, we ended up deciding to
scope back to a less ambitious model using only mid-plane fields until
we have need of 3D fields for focusing elements.

However, I do have another question for you. I'm interested in adding
3D RF fields to the model our group at Texas A&M has been working on,
to better capture the tapered geometry of our cavity of interest.
I've read through what the user manual has to say a few times and
believe it should be possible to specify mid-plane fields along with
3D RF using the BANDRF type, and an additional HDF5 input file.

Is there a specification of how the field data is stored in the H5Part
file format? I've poked around on the webside for H5Part a little and
found the H5Block structure [1], but the names that would be expected
for BANDRF are still unclear to me.  I've poked around a bit in the
OPAL source, but was wondering if you could point me to any
documentation on the subject.

Thanks,
James

[1] https://gitlab.psi.ch/H5hut/src/blob/master/doc/H5X_File_Format.txt

On Fri, Jan 27, 2017 at 12:04 PM, Chris Rogers <chris.rogers AT stfc.ac.uk> wrote:

Hi James,
Sorry the attachment seems to have gotten lost when Andreas sent the email
onto me. Is there any chance you could resend with the attachment?

Thanks,
Chris

On 20/01/17 07:53, Adelmann Andreas (PSI) wrote:

Hi James great that you are using OPAL.

Please repost this to opal AT lists.psi.ch you get a much larger
audience :-).

I cc: to Chris who wrote SBEND3D and surely can help you with that.


Cheers Andreas

On 19 Jan 2017, at 17:42, James Gerity <jgerity AT tamu.edu> wrote:

Dr. Adelmann,
I am trying to use OPAL to simulate transport in a cyclotron with
strong focusing, and would like to make use of the SBEND3D
functionality to specify the fields. I have some questions, and I've
tried to consult the OPAL manual, the source, and asked these
questions to Nate Pogue (one of our lab's alums), but have not yet
gotten the answers I need.

- Does SBEND3D use a local coordinate system, relative to the
beginning of the element? If so, how is this coordinate system
defined?

- Is the OPAL manual's description of the LENGTHUNITS correct? When
adding an SBEND3D, the diagnostic output from OPAL specifies the
lengths in both 'm' and 'mm,' it seems one of these is wrong and
confusing. I.e. `zini= -1.0000000000000000e+03 m; zfinal=
1.0000000000000000e+03 mm` for the input file attached.

As a test case, I have tried to propagate a beam through a simple π/6
sector (input files attached). However, the beam travels straight in
the initial direction, indicating to me that my element is either the
wrong size or placed incorrectly relative to the beam. Perhaps you can
shed some light on what I am misunderstanding about how this element
interacts with the global coordinate system.

Thanks,
James Gerity
<generate_fieldmap.py><sbend3D_test.in><testbend.bmap>

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--
ISIS Intense Beams Group

tel: +44 (0)1235 44 6983

Building R2,
Rutherford Appleton Laboratory,
Harwell Science and Innovation Campus,
Didcot.
OX11 0QX

Obama:
No matter what happens, the sun will rise in the morning.