transverse x x' update with csr
Posted: 13 Jan 2020, 01:13
Dear all,
Hello, I am currently studying the csr effects, and using the very simple case, I am trying to understand how transverse coordinates x and x' are changed with the csr effects.
In this case, I set CSRCSBEND with 'LINEARIZE = 1' to force the matrix calculation and 'STEADY_STATE = 1' for the simple calculation.
In addition, in order to reduce some noises from the bin setting, I used number of bins of 200 instead of 600 with the number of particles of 400k.
And then, using particle_output_file, I checked the output of each step.
I think the main reason of the shift of the centroid is due to the R16 * delta where delta is updated fractional energy spread by CSR.
Therefore, I made matlab script to recalculate this, but I could not get any shift of the centroid of x and x'.
I suspect I put something wrong in my calculations.
In the script, 6D phase space (x, x', y, y', p, t) was re-arranged by the order of time 't', and with respect to time (other information x, x', y, y', delta are following each particle's time) and then CSR energy change was calculated using Saldin's equation.
Then, I calculated updated fractional energy spread 'delta_updated' and then finally put this term to the transfer matrix calculation with arranged 6D phase space data with respect to the time. For instance, x_f = R16 * x_i + R26 * x'_i + R16 * delta_updated; sector bending magnet, where x_i and x'_i are the previous phase space components (before entering next step).
Could you please let me know how the transverse components x and x' (or px, canonical momentum) are updated during the energy change due to CSR in ELEGANT?
It would be very useful if I understand the process of the update of the transverse component due to the csr for the future study...
Thank you very much.
Best,
Seongyeol
Hello, I am currently studying the csr effects, and using the very simple case, I am trying to understand how transverse coordinates x and x' are changed with the csr effects.
In this case, I set CSRCSBEND with 'LINEARIZE = 1' to force the matrix calculation and 'STEADY_STATE = 1' for the simple calculation.
In addition, in order to reduce some noises from the bin setting, I used number of bins of 200 instead of 600 with the number of particles of 400k.
And then, using particle_output_file, I checked the output of each step.
I think the main reason of the shift of the centroid is due to the R16 * delta where delta is updated fractional energy spread by CSR.
Therefore, I made matlab script to recalculate this, but I could not get any shift of the centroid of x and x'.
I suspect I put something wrong in my calculations.
In the script, 6D phase space (x, x', y, y', p, t) was re-arranged by the order of time 't', and with respect to time (other information x, x', y, y', delta are following each particle's time) and then CSR energy change was calculated using Saldin's equation.
Then, I calculated updated fractional energy spread 'delta_updated' and then finally put this term to the transfer matrix calculation with arranged 6D phase space data with respect to the time. For instance, x_f = R16 * x_i + R26 * x'_i + R16 * delta_updated; sector bending magnet, where x_i and x'_i are the previous phase space components (before entering next step).
Could you please let me know how the transverse components x and x' (or px, canonical momentum) are updated during the energy change due to CSR in ELEGANT?
It would be very useful if I understand the process of the update of the transverse component due to the csr for the future study...
Thank you very much.
Best,
Seongyeol