Run 19 Capabilities

TMO capabilities for Run 19

The new Time-resolved Atomic, Molecular and Optical Science instrument (TMO) will provide access to the first Interaction Point (IP1) in Run 19. TMO is optimized to support AMO science, strong-field, and nonlinear science areas. A new variable gap undulator system will be used, providing horizontal polarization for photon energies from 250 eV to 2100 eV, with pulse energies expected to be in the 0.1 to 5 mJ range. In Run 19, TMO will operate with the 120 Hz copper accelerator. Ultra short pulses (XLEAP) should be available for user proposals. Proposals should target experiments using up to 120 Hz beam delivery.

Key Performance Parameters for Run 19

TMO will operate in Run 19 with the following performance parameters.   




Repetition Rate (Hz)

Up to 120, (1, 10, 30, 60, 120) 

Energy Range (eV)

270 - 2100

Pulse Duration (fs)

≤ 40; plus XLEAP capability (see below)

Spot size range, FWHM (um)

1.0 - 100


Linear, horizontal 

Single Pulse Energy (mJ)

Up to 4

Two Bunch, Two Color Mode


Split Undulator

Available, includes XLEAP
Minimal delay depends on setup. 


XLEAP Parameter


XLEAP Pulse Duration (fs)

≤ 0.6

Pulse Energy, single shot (µJ)

25 - 75 (single pulse), ~10 uJ /pulse for split undulator.

Bandwidth FWHM (eV)

4 - 8



Run 19 proposals using XLEAP should be consistent with using single X-ray pulse delivery. LCLS intends to commission dual sub-femtosecond pulses with tunable energy and delay, but this is not guaranteed for Run 19. If the two pulse attosecond operation is successfully developed, the option to use attosecond pulse pairs may be presented during the run. Users should assume added risk and prepare for extended tune up periods.  Note, that on soft X-ray two-pulse operation for Run 19, two pulse modes will be limited in delay range. Accessible delays will be between +5 fs and +1000 fs.  For more information, please contact James Cryan ( or Peter Walter (


Optical Laser Parameter


Wavelength (nm) 

266, 400, 800, 1200 - 2300*

Pulse Duration at 800 nm (fs) FWHM

< 50

Repetition rate (Hz)

Variable to 120 Hz, shot on demand

Peak intensity on target  for 800 nm (W/cm2)


Variable energy attenuation factor (800 nm)

0 - 10

Polarization (2300 nm and below)

beamline y, beamline x, or circular

Focus diameter for 800  (um)

50 to 100 

“Goose” laser on-off trigger available

0-100% duty cycle

*IR wavelengths out to ~5 microns are possible in run 19, but depending on the pulse energy and bandwidth requirements this may require a separate laser setup that is not considered a standard configuration.  For more information on the available laser parameters, please contact Mike Glownia (

TMO spectrometers for Run 19 in IP1

For more information, please contact Peter Walter

Double Sided VMI

Ref: Osipov, et. al., (2018). The LAMP instrument at the Linac Coherent Light Source free-electron laser. Review of Scientific Instruments,
Standard Config:

  • Dual skimmed molecular beam with CW or pulsed valve (E-L or parker), horizontal orientation
  • Double-sided Velocity map imaging spectrometer
    • Electron VMI: DE/E < 10%, max KE ~100 eV, MCP/Phosphor screen with CCD
    • Ion VMI: MCP with delay-line anode (Quad)

Coaxial VMI 

Ref:  Cryan, J., et. al., (2018). A co-axial velocity map imaging spectrometer for electrons. AIP Advances,

Standard Config:

  • Skimmed molecular beam source (1 skimmer), vertical orientation
  • Velocity Map Imaging Spectrometer MCP/Phosphor screen with CCD
    • Electrons: DE/E < 10%, max KE 600 eV

Magnetic Bottle 

For Run19 TMO will provide a 2m long magnetic bottle electron spectrometer.

Standard Config:

  • Gas targets introduced through gas needle
  • 2m flight tube with retardation section, >50% collection efficiency
    • Expected Resolution: DE/E < 1%
    • Retardation capabilities upto 1 keV.   
    • Ion extraction plates 


For Run 19 TMO can provide a ETF11B electron time of flight spectrometer. This can be attached to either LAMP or cVMI endstation, either in the interaction region or downstream.

Resolution: DE/E ~ 1%, 45 deg collection angle


Not Available in Run19

  • DREAM (IP2)
  • Photon imaging detectors
  • Cookiebox aka MRCOFFEE