CSR Entrance Wakefield ( drift to bend )
Posted: 18 Apr 2019, 14:12
Dear Elegant Team:
I'm running CSR simulation on a simple lattice using a low-charge beam.
The lattice consists of a CSRdrift(D1), a CSRCSbend (B1), then CSRdrfit(D2).
My goal is to see the plot CSR wake seen by the bunch,
So for B1 I specified the "OUTPUT_FILE" filename,
and for D1 and D2 I specified the "STUPAKOV_OUTPUT" filenames. (See the lte file I attached)
After running ELEGANT, B1 and D2 both generate a file containing the CSR wake data, but D1 does NOT.
It's fair to note that CSR wake is absent in the initial drift D1, BUT what happens to the entrance wake when the head of the bunch enters the bend? In the 2002 Proceeding paper by G.Stupakov and P.Emma figure 1, this was referred as the entrance wake. And I wonder how to access this wake from Elegant. ( On the other hand, it is clear that Elegant calculates the "exit wake", which can be accessed from the output data file from D2. )
Another question is that, what exactly is the"DeltaGamma" quantity from the output files from B1 and D2? (see the two images I attached ) In the documentation for CSRdrift (https://ops.aps.anl.gov/manuals/elegant ... ode72.html ), it seems to imply the quantity is the unitless wake W(s) in G.Stupakov's formulas. I'd like to confirm that this DeltaGamma(s) is actually W(s), without extra normalization factors.
Another side question... is it possible to superimpose a WATCH in the middle of the CSRCSBEND? If not, what's a good way to access beam information in the middle of en element?
Thanks a lot.
Sincerely,
William
I'm running CSR simulation on a simple lattice using a low-charge beam.
The lattice consists of a CSRdrift(D1), a CSRCSbend (B1), then CSRdrfit(D2).
My goal is to see the plot CSR wake seen by the bunch,
So for B1 I specified the "OUTPUT_FILE" filename,
and for D1 and D2 I specified the "STUPAKOV_OUTPUT" filenames. (See the lte file I attached)
After running ELEGANT, B1 and D2 both generate a file containing the CSR wake data, but D1 does NOT.
It's fair to note that CSR wake is absent in the initial drift D1, BUT what happens to the entrance wake when the head of the bunch enters the bend? In the 2002 Proceeding paper by G.Stupakov and P.Emma figure 1, this was referred as the entrance wake. And I wonder how to access this wake from Elegant. ( On the other hand, it is clear that Elegant calculates the "exit wake", which can be accessed from the output data file from D2. )
Another question is that, what exactly is the"DeltaGamma" quantity from the output files from B1 and D2? (see the two images I attached ) In the documentation for CSRdrift (https://ops.aps.anl.gov/manuals/elegant ... ode72.html ), it seems to imply the quantity is the unitless wake W(s) in G.Stupakov's formulas. I'd like to confirm that this DeltaGamma(s) is actually W(s), without extra normalization factors.
Another side question... is it possible to superimpose a WATCH in the middle of the CSRCSBEND? If not, what's a good way to access beam information in the middle of en element?
Thanks a lot.
Sincerely,
William