Overview
Beam line 7-3 is a high flux wiggler side-station optimized for x-ray absorption spectroscopy (XANES and EXAFS) in the 5.5–40 keV range, dedicated for x-ray absorption spectroscopy and EXAFS measurements on dilute biological systems. A dedicated LHe cryostat allows for routine low temperature measurements. The unfocused beam on BL7-3 is ideal for samples especially susceptible to radiation damage, such as high-valent intermediates and other oxidized species.
The station features a double-crystal Si(220) monochromator with energy resolution up to 10-5 (ΔE/E)and small vertical entrance slits to reduce intensity glitches. Equipment includes a Canberra 30-element Ge detector for dilute samples, a passivated implanted planar silicon (PIPS) semiconductor detector for fluorescence detection, ionization chambers for transmission data, and LHe cryostats for maintaining samples at ~10 K (10-100 K default configuration, 4-200 K with LHe dewar.
Source: 20-pole, 2-Tesla wiggler side station, 0.8 mrad acceptance
Status —
Beamline Parameters —
| Energy Range | Resolution ΔE/E | Spot Size | Flux | |
|---|---|---|---|---|
| Unfocused | 5500-40000 eV | 1 x 10-4 | 2 x 12 mm2 | 2 x 1012 |
Optics —
| Monochromator: |
|---|
| Si(220), ϕ = 0o & 90o. double-crystal, variable-exit geometry |
Source —
Instrumentation —
| Detectors | Canberra 30-element germanium solid state detector with Xspress3X electronics. Passivated implanted planar silicon (PIPS) semiconductor detector. Ionization chambers. |
|---|---|
| Ancillary | Soller slits and scatter guards, sample shutter to alleviate beam damage, automatic scan queueing for multiple samples/multiple spots on samples. Oxford Helium cryostat, cooled either by closed-cycle cooled He gas loop (10-100 K) or by open-cycle liquid He dewar (4-200 K) |
Sample Environment —
| Standard Cryostat | Sample temperature ~10 K: |
|---|---|
| Single solid sample | |
| 4-slot solid sample cassette | |
| Single solution sample | |
| 5-slot solution sample cassette | |
| Mossbauer cups |
Absorption —
| 762 microns Be, 205 microns C |
|---|
Publications
Publications
Highlights
Science Highlights
We are in the process of porting over science highlights from our previous system. You can access new highlights and a portion or our catalog here.
For science highlights dated before 2021 visit this site. Use the filters to narrow down your search by year and beam line.