The OPAL Discussion Forum

[raoyn AT triumf.ca]

I forgot to say in my previous e-mail that the inital Delta p/p of this
particle is zero.

--
Yi-Nong


> Andreas,
>
> Further to Norman's e-mail, I  want to make it clearer as to what the
> issue is.
>
> What he did was a simple test to OPAL:  track a single particle through
> a 90 degrees
> magnetic S-bender with the fringe field turned off.  The initial X is
> -0.004m while initial
> PX is 0.  (Initial means at the  entrance of the magnet.)   The X,PX
> values were recorded
> at each step of the numerical integration up to the exit of the magnet.
> As a result of
> OPAL tracking,  X vs S appears to a cosine curve as expected (please
> look at Page 3 of
> Norman's summary "SBEND-results.pdf"), while PX vs S shows funny numbers
> near
> zero instead of a sine curve (see Page 7).   I don't understand this.
> We cannot figure out
> why from your source code.
>
> It makes no sense to track multiple particles if a single particle
> tracking does not give
> correct result.  We may have misunderstood something. Could you take a
> careful look at
> Norman's input and output files and help us out?
>
> Thanks in advance.
>
> Yi-Nong
>
>
> Norman Huang wrote:
>> Yi-Nong and I do not know how to interpret these SBEND results. Please
>> take a look at my test cases summary. Attached are the OPAL input file
>> (qf.in), Enge coefficient file (FAND1.T7), single particle tracking
>> data (particleInfo_Fringe.txt, particleInfo_NoFringe.txt)
>>
>> The 12 columns for the particleInfo files are:
>> Bx     By     Bz     X_ref     Y_ref     Z_ref     Px     Py
>> Pz     X_local     Y_local     Z_local
>>
>> Regards
>> Norman
>
>
>