4B7A is a Medium Energy Beamline and locates at No.12 experimental hall. It is a bending magnet end station dedicated to medium-energy XAFS spectroscopy.It mainly consists of high vacuum measurement chamber, low vacuum measurement chamber, He gas environment measurement room, Transfer chamber, sample pretreatment device and MBE device. Usually two types of detection modes are in use for measuring XAFS of elements: partial fluorescence yield (PFY) and  total electron yield (TEY) . The energy range of this beamline is from 1.7keV to 5.8keV ,which covers the K-edge elements Si, P, S, Cl, Ar, K,Ca ,Ti and L-edge of of the rare earth elements. All of these elements play important roles in the fields of geoscience mcircumstance science, circumstance science and bioscience, and the clear understanding and comprehension about the nature of the substances formed by these elements are the key ones related to our national economic and social development.This beamline runs not only in the dedicated mode of synchrotron radiation but also in the  parasitic mode.

Supported techniques:

Mid-energy X-ray spectroscopy

Optical metrology

Scopes:

Environment science

Biology

Materials

Agriculture

X-ray metrology

Beamline equipments

13 element fluorescence detector

Cryogenic equipment

On-line annealing device

Beamline Specs

Source                                    BM

Monochromator Type         Si (111), InSb(111)  

Energy Range                       2050-5700 eV, 1700-3400 eV  

Flux (photons/sec)               10¹⁰ @ S K edge

Resolution (E/ΔE)                 7000

Beam Size (HxV)                    3mm×1mm