Elegant users forum

Ji-Gwang,

I can't duplicate the problem with version 2022.0. I've attached my files.

--Michael

Chao, This is outside my expertise, but I understand that there are various methods to transform a digital filter into an analog equivalent and vice-versa. In our 2015 IPAC paper on rf feedback, my colleague Tim Berenc recommends using a bilinear transform. The reference is to M. Santina et al. W. S...

Ji-Gwang,

Thanks for the lattice file. Can you also post the .ele file?

--Michael

The problem is that the tracking.ele file isn't constructed correctly to generate the .twi file. See the attachment for a file that should work. (Basically, requesting a twiss output file during an optimization isn't supported. It has to be done after the optimization in a second sequence.) --Michael

Perhaps this post will help
viewtopic.php?f=9&t=857

--Michael

The reason for this is that your beam line contains dipole magnets with small bending radii. There are sextupole-like terms present in such magnets due to the small radius of curvature of the coordinate system. This results in distortion of the phase space, which shows up as a small centroid error. ...

Ji-Gwang,

There may have been some changes in orbit correction methods that affect your simulation. However, without the files I can't tell.

Please upload all the files necessary to reproduce the problem.

--Michael

Ji-Gwang,

The problem is that Pelegant can't read ASCII files using parallel I/O. Just convert the files to binary form: --Michael

The 40-cm depth is defined by the D2 element, which defines the drift space between the last quadrupole and the end of the beamline.

--Michael

Using the Java or Tcl/Tk SDDS editor is a good approach. One can also use "sddsconvert -ascii <filename>" and then edit the file with any text editor; its a good idea to use sddscheck to validate the file after editing by hand.

--Michael