Table 2. Parameters of the LCLS II injector.

Parameter	Value	Unit
Drive laser
Beam charge Q	100	pC
Laser temporal profile	Flat-top
Flat-top FWHM	32.91	ps
Flat-top edge width	2	ps
Transverse r.m.s. size	0.1923	mm
Thermal emittance	0.1923	µm
VHF gun
RF frequency of gun	186	MHz
Maximum acceleration gradient	20.04	MV m−1
Injection phase	−6.5959†	degree‡
Buncher
RF frequency of buncher	1.3	GHz
Maximum acceleration gradient	1.7942	MV m−1
Acceleration phase	−80.2745	degree
Cavity position	0.8093	m
Eight-cavity cryomodule
First cavity position	3.3428	m
RF frequency of cavity	1.3	GHz
Maximum gradient of 1st cavity §	15.8	MV m−1
Acceleration phase of 1st cavity	−4	degree
Maximum gradient of 2nd/3rd cavities	0	MV m−1
Maximum gradient of 4th cavity	28	MV m−1
Acceleration phase of 4th cavity	0	degree
Maximum gradient of 5th–8th cavities	32	MV m−1
Acceleration phase of 5th–8th cavities	0/0/1.25/6	degree

^†Relative phase to the maximum acceleration.

^‡Degree in the corresponding cavity RF frequency.

^§The gradient refers to the maximum gradient in the cavity and the average gradient can be estimated by the energy gain over the whole cavity.