MeV-UED Endstations

Solid State (Materials) & Warm Dense Matter (Single Shot) Endstation
Sample motion	5-axis sample motion Transverse to beam: X (horz): 50 mm (5 um resolution) Y (vert): 25 mm (0.1 um resolution) Along beam: Z (horz): 25 mm (5 um resolution) Rotations: Yaw (about Y): +/- 45 degrees Pitch (about X): +/- 45 without cooling; +/- 15 with cooling.
Sample Cooling	30 - 300 K
Diagnostics	Frosted YAG for electron/laser overlap Single-crystal gold for q reference Si temperature sensor Bi for time-zero reference
Sample mounting	TEM mesh grids TEM Si3N4 membranes Si3N4 membrane arrays (contact)
Vacuum	<1 x10^-7 Torr

Solid State (Materials) & Warm Dense Matter (Single Shot) Endstation

Sample motion

5-axis sample motion
Transverse to beam:
    X (horz): 50 mm (5 um resolution)
    Y (vert): 25 mm (0.1 um resolution)
Along beam:
    Z (horz): 25 mm (5 um resolution)
Rotations:
    Yaw (about Y): +/- 45 degrees
    Pitch (about X): +/- 45 without cooling;
                                    +/- 15 with cooling.

Sample Cooling

30 - 300 K

Diagnostics

Frosted YAG for electron/laser overlap
Single-crystal gold for q reference
Si temperature sensor
Bi for time-zero reference

Sample mounting

TEM mesh grids
TEM Si3N4 membranes
Si3N4 membrane arrays (contact)

Vacuum

<1 x10^-7 Torr

UED Gas Phase Endstation
Sample Temperature Range	Sample reservoir: RT - 100 °C (flow cell) & RT - 150 °C (pulsed nozzle) Transport line : RT - 80 °C (flow cell) & RT - 180 °C (pulsed nozzle) Pulsed nozzles : RT - 200 °C Flow cell: RT to ~ 100 °C
Sample Vapor Pressure Requirement	> 100 torr at 150 °C for pulsed valves > 0.5 torr at RT for flow cell (3 to 4 mm path length)
Sample Reservoir Size	100 mL (e.g. standard 2.75 CF nipple)
Buffer Gas (optional)	Helium, 5 bar for Parker general valve
Nozzle Properties	Pulsed, up to 180 Hz 100 - 200 µm orifice Typical opening time: 100 - 300 µs
Gas Jet Size (FWHM)	200-400 µm
Nozzle motion	3-axis translational motion X (Horizontal in lab, perpendicular to beam propagation direction): 2" Y (Vertical in lab): 2" Z (Horizontal in lab, beam propagation direction): 2"
Cold Trap Temperature	< 100 K
Diagnostics	Frosted YAG for electron/laser overlap Single-crystal Au/Si for Q reference and time zero reference (within 400 fs)
Pump-probe propagation angle	~2°
Vacuum	Operation condition: Flow cell operates at 1-10 Torr Background pressure ~1e-5 - 1e-4
Gas Line Material	Stainless Steel
Nozzle Puppet/Seal Materials	Vespel (Parker general valve; series 9) Polyimide (for high repetition rate valves)
Flow cell materials	(1) Stainless steel (2) Macor ceramic
Q range	0.5 to 12 Å^-1
Q resolution (FWHM)	0.17 Å^-1
Time resolution (FWHM)	150 fs
Pump Wavelength	200 nm, 266 nm, 400 nm, 800nm, 240 nm - 2 µm tunable
Delay Stage Range	2 ns
Delay Stage Resolution	7 fs

UED Gas Phase Endstation

Sample Temperature Range

Sample reservoir: RT - 100 °C (flow cell) & RT - 150 °C (pulsed nozzle)
Transport line : RT - 80 °C (flow cell) & RT - 180 °C (pulsed nozzle)
Pulsed nozzles : RT - 200 °C
Flow cell: RT to ~ 100 °C

Sample Vapor Pressure Requirement

> 100 torr at 150 °C for pulsed valves
> 0.5 torr at RT for flow cell (3 to 4 mm path length)

Sample Reservoir Size

100 mL (e.g. standard 2.75 CF nipple)

Buffer Gas (optional)

Helium, 5 bar for Parker general valve

Nozzle Properties

Pulsed, up to 180 Hz
100 - 200 µm orifice
Typical opening time: 100 - 300 µs

Gas Jet Size (FWHM)

200-400 µm

Nozzle motion

3-axis translational motion
X (Horizontal in lab, perpendicular to beam propagation direction): 2"
Y (Vertical in lab): 2"
Z (Horizontal in lab, beam propagation direction): 2"

Cold Trap Temperature

< 100 K

Diagnostics

Frosted YAG for electron/laser overlap
Single-crystal Au/Si for Q reference and time zero reference (within 400 fs)

Pump-probe propagation angle

~2°

Vacuum

Operation condition:
Flow cell operates at 1-10 Torr
Background pressure ~1e-5 - 1e-4

Gas Line Material

Stainless Steel

Nozzle Puppet/Seal Materials

Vespel (Parker general valve; series 9)
Polyimide (for high repetition rate valves)

Flow cell materials

(1) Stainless steel (2) Macor ceramic

Q range

0.5 to 12 Å^-1

Q resolution (FWHM)

0.17 Å^-1

Time resolution (FWHM)

150 fs

Pump Wavelength

200 nm, 266 nm, 400 nm, 800nm, 240 nm - 2 µm tunable

Delay Stage Range

2 ns

Delay Stage Resolution

7 fs

MeV-UED Contact Info

Mike Minitti

Director, MeV-UED
(650) 926-7427
minitti@slac.stanford.edu

Joel England

UED Accelerator Lead
(650) 926-3706
england@slac.stanford.edu

Alex Reid

UED Instrument Lead
(650) 926-7467
alexhmr@slac.stanford.edu

Xiaozhe Shen

UED Facility R&D Lead
(650) 926-2899
xshen@slac.stanford.edu

Ming-Fu Lin

Associate Staff Scientist
(650) 926-2586
mfucb@slac.stanford.edu

Matthias Hoffmann

Laser Scientist
(650) 926-4446
hoffmann@slac.stanford.edu

Patrick Kramer

Laser Scientist
(650) 926-5148
pkramer@slac.stanford.edu

Xinxin Cheng

Associate Staff Scientist
xcheng@slac.stanford.edu

Fuhao Ji

Research Associate
(650) 926-4678
fuhaoji@slac.stanford.edu

Stephen Weathersby

UED Area Manager
(650) 926-3890
spw@slac.stanford.edu