TMO (Time-resolved AMO)

The TMO instrument (NEH 1.1), one of the three new LCLS-II instruments with a energy range from 0.25 to 2 keV, will support a wide range of science including gas phase photochemistry, attosecond electron dynamics, and the study of nanoscale systems. TMO will support an array of experimental techniques and features two X-ray focus positions. The NEH beamline 1.1 science end station, will be configured to take full advantage of both the high per pulse energy from the copper accelerator (120 Hz) as well as high average intensity and high repetition rate (1 MHz) from the superconducting accelerator.

Endstation Descriptions

The initial TMO focus spot or interaction point, IP1, is optimized for performing high energy, high resolution, time-but also angular-resolved photoelectron spectroscopic measurements. This interaction point features an array of standardizied, modular endstations. Depending on the photon energy, IP1 X-ray photon fluence can reach the high 10¹⁹ photons/cm² range with superconducting Linac, and high 10²⁰ photons/cm² range with copper accelerator at 120 Hz.

The second TMO focus spot (IP2) features the new Dynamic REAction Microscope (DREAM) endstation which is a reaction microscope (or COLTRIMS type) spectrometer as a standard configuration. A second set of focusing mirrors defocus the IP1 spot to produce sub-mircon x-ray focal spots. The reaction microscope techniques is well suited for accumulating data on the event-by-event basis at the rep rates in excess of 100 kHz fully utilizing the LCLS-II capabilities. Photon fluence in IP2 will reach beyond 10²¹ photons/cm² with superconducting Linac X-rays, while with copper accelerator it will be over 10²² photons/cm² at 120 Hz.

Pump-probe timing resolution of X-ray with optical laser pulses can be expected to exceed 10 fs for both endstations.