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SubjectSAD Update. V1.0.10.4a01 Bug in EMIT, etc.
Article No767
Date: 2010/01/16(Sat) 11:35:05
ContributorK. Oide
Dear Users:

1. It was found that the routine in the emittance calculation has not taken the momentum closed orbit into account in the estimation of the quantum excitation of the momentum beam matrix, i.e. <px^2>, {px py>, <px p>, etc. Thus the error becomes huge when the momentum closed orbit (i.e. orbit angle) is large as in a solenoid with orbit angle. This bug has been there almost from the beginning of the emittance calculation in SAD, probably around 1988. This bug only affects EMIT and Emittance[] and has no effect in optics calculation or tracking with radiation.

2. Now APERT takes keywords AX, AY, DX, DY to scrape particles with the condition

(x - DX)^2/AX^2 + (y - DY)^2/AY^2 >= 1 .

If either AX == 0 or AY ==0 (default), the scraping with AX, AY is not effective. If both AX and AY are nonzero, then scraping with DX1, DX2, DY1, DY2 are ineffective when DX1==DX2 or DY1==DY2.

3. Now an APERT element can be inserted in a solenoid region.

SubjectRe: SAD Update. V1.0.10.4a07
Article No768
Date: 2010/01/19(Tue) 06:15:07
ContributorK. Oide
Dear Users,

1. Due to the change in 1.0.10.4a00, the calculated emittance for a chicane becomes almost same no matter it is expressed by ANGLE or K0. Then an error was found in a term in the damping matrix, related to E1 and E2. It has been corrected in the new version, 1.0.10.4a07, then the agreement between ANGLE and K0 becomes complete.