Experimental Station 15-2 | Stanford Synchrotron Radiation Lightsource

Beamline 15-2 is an undulator experimental station dedicated to advanced hard x-ray spectroscopy. The end station is equipped with sub-corehole lifetime resolution x-ray emission spectrometers (a 7-crystal Johann spectrometer and a 8 crystal von Hamos instrument) as well as a high-throughput and high energy resolution (0.3eV) 40-crystal low-q x-ray Raman spectrometer. The end-station also incorporates a high-power MHz repetition laser together with fast diodes and FPGA electronics enabling laser pump x-ray probe time-resolved spectroscopies (~75ps time resolution) using the camshaft bunch (~20mA) of SPEAR3. Advanced sample environments including electrochemical cells, thermal catalysis reactors, cryostats, continuous flow liquid jets, microfluidic mixers and other in situ environments enable a multipurpose scientific program across catalysis, energy science, biochemistry, environmental science as well as actinides research.

Status

Open

Supported Techniques

Pump-Probe

X-ray Absorption Spectroscopy

Resonant inelastic x-ray scattering

X-ray emission spectroscopy

X-ray RAMAN spectroscopy

Main Scientific Disciplines

Bioscience

Catalysis

Energy Science

Materials Sciences

Beam Line Specifications

Source

87 period in vacuum undulator

	Energy Range	Resolution ΔE/E	Spot Size	Flux	Angular Acceptance
Focused	4800-18200	1.0-15 10^-5	5x35um2 (or 100x700um2)	~3x10¹³ ph/s (Si111) ~ 4x10¹² ph/s (Si311)	N/A
Unfocused	18000-24000	10^-4	500x2000um2	~ 4x10¹¹ ph/s (Si311)	N/A

Optics

M1 KB mirrors: Bent single crystal KB mirrors for a vertical and horizontal beam focusing. Rh and Si stripes provide selectable cutoffs at 11keV and 18.2 keV, respectively.

Monochromator: LN2 cooled, Si(111), ϕ = 0o , Si(311), ϕ = 0o. double-crystal.

Absorption

127um Be

Instrumentation

7-crystal XES spectrometer (http://dx.doi.org/10.1063/1.4803669 (link is external)) 40-crystal XRS (http://dx.doi.org/10.1063/1.4704458 (link is external))
8-crystal von-hamos XES spectrometer (https://doi.org/10.1063/1.4737630 (link is external))
Detectors: multiple single element Vortex solid-state; PIPS diodes, APD diodes, ionization chambers, Pilatus, and Eiger-X.
Cryostat: Oxford LHe cryostat (4-200 K)
Other: Integrated fast shutter system and variable filters to alleviate radiation damage. High power and high rep rate laser: Amplitude Tangerine 50W Colby time-delay unit Teledyne Wavemaster 816ZI-B oscilloscope 16 GHz, 80 GS/s) Teledyne ADQ-14bit 4-channel digitizer card (1GSPS/channel).

Sample Environment

Ambient pressure experiments, He chamber(s), flexibility with various in-situ setups including electrochemical cells and thermal reactors for operando catalysis, liquid samples and liquid jets, high pressure. Dedicated LHe cryostat (4-200 K).

Minimum sample requirement (in terms of concentration): Typically, end-station can measure sub-100umol concentrations and sub monolayer materials. Feasibility depends strongly on the technique and the scientific question. Please contact responsible scientific staff for guidance.

Data Acquisition and Analysis

SPEC, PyMCA, Matlab, Python

Beam Line Phone

650-926-5115. On-site Users: Contact the Duty Operator at 9-926-4040

Beam Line Contact

Content Owner: N Stojanovic | Last updated: 12/11/2022