Feedback on Version 5 of the Paper

[cyjwong]

In the paragraph before equation (6), there is a sentence which says that "Therefore, the number of turns N_turns is limited by the selected 10cm horizontal apertures x_max of the bending magnets" I believe 10cm is the aperture of the quads, and it is the quads, not the dipoles, that limit the number of turns.

I wonder if equation 6 is erroneous. From where delta_E is the energy loss per turn, and N*delta_E denotes the max. allowed energy loss. This divided by the total E should equal the max. allowed dispersive shift divided by the dispersion function. Hence the modified equation would be of the form:

In Table 3, I believe the bending radius and dispersion function of the 1 GeV s.c. case should be 0.33m rather than 0.83m

In the last sentence of the first paragraph in Discussion, it mentions a beam size of sigma_r = 5 micron. I am not sure I understand this correctly, because, according to Table 3, the beam size is at least 500 micron when the electron beam is circling the ring.

[ghost]

Hi Jonathan,

Where did you get this equation from? because in the last version I sent out formula 6 is different. (I got it from Brandon) na_pac_uspas_v5.pdf

Thanks for the bending radius and dispersion, that was indeed a typo.

[cyjwong]

Hi Marlene, I believe formula 6 in the latest version has an error, and the equations I showed are what I thought should be the correct form of formula 6.

The existing formula fails a dimensional analysis. The left hand side, N_turns, is dimensionless, whereas the right hand side has dimension (eV)^-1.

I am sorry for the confusing notation in my initial post. Capital-delta_E was meant to be the energy loss per turn.

Perhaps this would be clearer:

x_max - 2*delta-x is the maximum allowed dispersive shift. It should equal the dispersion function times the maximum allowed fractional energy loss. The maximum allowed energy loss equals the energy loss per turn times N_turn.

Rearranging the terms lead to:

[ghost]

you're right, thanks a lot!