RF upgrade for lifetime improvement

Increasing the RF voltage in order to raise the RF MA or installation of a 3^rd harmonic cavity for bunch lengthening are two options for increasing the Touschek lifetime. Higher voltage gains little lifetime, at least for the lattice mode investigated here. The harmonic cavity however, fighting Touschek effect at its origin instead of curing the consequences, would lengthen the bunch and correspondingly the Touschek lifetime by a factor of 4 and thus is the method of choice [9]. The following table displays results of Touschek and total lifetime assuming 4 mm gap insertions without and with a 3^rd harmonic cavity³:

Vrf	Touschek	Gas	Total
[MV]	[hrs]	[hrs]	[hrs]
2.6 [+3rd harm.cav.]	4.8 [19]	14	3.6 [8.1]
4.2 [+3rd harm.cav.]	5.9 [24]	14	4.2 [8.8]