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BL18: General-Purpose Powder Diffractometer

Date: 2017-03-15

Instrument Contact: Dr. HE Lunhua 

Email: lhhe@ihep.ac.cn 


The general-purpose powder diffractometer (GPPD) is the first powder diffractometer at the China Spallation Neutron Source (CSNS). It aims to provide a high-resolution, good-intensity instrument for users to study crystallographic and magnetic structures. The best resolution is better than 0.2% at high-angle detector bank. The neutron flux at the sample position is at the order of 107 n/s/cm2. The joint beam commissioning among accelerators, target station and instruments started in the China Spallation Neutron Source (CSNS) on November 1, 2017. 



1. Best resolution Δd/d ~0.2 %.

2. ~ mimutes for a diffraction histogram used by Rietveld refinement on ~ 1-g-weight sample

3. Easily loading the ancillary equipment such as cryostat, furnace and pressure cell




Moderator DPHM(20 K)
Bandwidth(Δλ) 4.5 Å
Max. Beam Size 40(h)×20(w) mm
Flux at sample position ~107 n/cm2/s
Guide Taper focus, m=3
Source to sample distance L1 30 m