Table 1 The training variables (data label), v1, v2, v3, v4, v5, and v6, with respect to the electron properties (input data), p1, p2, p3, p4, p5 and p6, are listed, including the upper maximum and lower minimum limits for all parameters and their physical definitions.

From: Toward fully automated UED operation using two-stage machine learning model

Variable

Min

Max

Unit

Formula

Description

Beam properties

Formula

Description

v1

0

5

μm

xoff

x-jitter

p1

avg(x)

x-position

v2

0

5

μm

yoff

y-jitter

p2

avg(y)

y-position

v3

30

220

μm

σr

Spot size

p3

std(x')

x-divergence

v4

− 0.025

0.025

 

∆VRF/ VRF

RF amplitude jitter

p4

std(y')

y-divergence

v5

5

60

degree

θgun

RF phase

p5

∆G

Energy spread

v6

0

0.4

 

I / Imax

Solenoid factor

p6

G

Energy

  1. Compared to the RF synchronization (θgun) and fluctuations (∆VRF / VRF), the laser pulse duration (σt) and total charge (Qtot) are more stable and fixed in the GPT simulation.