Riccardo De Maria

p_t and delta dependence in twiss are problematic when h!=k0. Here an example: ``` ss: sequence,l=1; m: multipole,knl={0},angle=0.15,at=0; endsequence; ``` is a thin multipole with no field and curvature. Effectively,...

dipole issue in twiss with k0!=h and/or deltap!=0

1

In twiss the dipole map is calculated by tmsect using h and dh as parameters defined by: ```fortran if (sk0 .ne. 0) then- f_errors(0) = f_errors(0) + (sk0*el - angle)...

Differently from twiss, track does not support the delta_s parameter: https://github.com/MethodicalAcceleratorDesign/MAD-X/blob/8695bd422dc403a01aa185e9fea16603bbd5b3e1/src/trrun.f90#L3348 where deltae is pt from the start command https://github.com/MethodicalAcceleratorDesign/MAD-X/blob/8695bd422dc403a01aa185e9fea16603bbd5b3e1/src/mad_track.c#L295 while deltap is taken from the delta parameter in track:...

First twiss gives wrong dqmin

3

``` In [25]: mad = Madx(stdout=False) ...: mad.call('hllhc15_noerrors_nobb/sequence.madx') ...: mad.use('lhcb1') ...: print( mad.twiss().summary.dqmin ) ...: mad.sequence.lhcb1.expanded_elements[7].ksl = [0, 1e-4] ...: print( mad.twiss().summary.dqmin ) ...: print( mad.twiss().summary.dqmin ) ...: 1.357027643e-10 0.0001892528266...

twiss energy loss does not take the gamma of the closed orbit correctly into account.

2

Reported by Jacqueline and Tobias. A term (1+delta) in https://github.com/MethodicalAcceleratorDesign/MAD-X/blob/master/src/twiss.f90#L3912 appear to be missing. Similarly to #1082

It should be possible to remove the warnings by using the IEEE interface (reported by S. Berg)

NOTSIMPLE option in APERTURE looks broken

1

Report by Massimo and Gustave

KSI silently ignored for solenoids with L>0

5

SOLO: SOLENOID, L = 2., KSI = 0.001; succeds but KSI is ignored

issue with combined function magnet and emit

1

The attached script gets 2 different emittance values (diff by about factor 2) when changing the k1 in the dipole just by 1.5e-16 m^{-2} (which does not even change tunes...