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[ Identification | Description | Input parameters | Links ]

The ISIS_MERLIN Instrument


  • Site: ISIS
  • Author: Rob Bewley
  • Origin: ISIS (UK)
  • Date: May 2017.


Merlin has been in user operation since 2008. It was designed to be a high intensity, medium energy
resolution spectrometer that would complement the high-resolution MAPS spectrometer, and replace
the HET spectrometer. Merlin's design exploited recent advances in technology with a supermirror
guide to enhance flux, as well as 3 m long position-sensitive detectors in a vacuum, making it
ideal for the study of single crystals. The detector bank covers a massive \pi steradians of solid
angle with an angular range from -45 to 135 degrees in the horizontal plane, and \pm 30 degrees in
the vertical plane. This allows large swathes of Q,\omega space to be accessed in a single run.

Since 2014, Merlin has been running in event mode, and by using the new Gd chopper combined with a
disk chopper, it is able to run in repetition-rate multiplication (RRM) mode, allowing users to
simultaneously measure with several incident energies.

Input parameters

Parameters in boldface are required; the others are optional.
E_minmeVlowest energy sampled [meV]1.0
E_maxmeVhighest energy sampled [meV]2000.0
mfloatm value of guides3.0
E_focmeVenergy selected by chopper [meV]80.0
nu_hzHzfrequency of chopper rotation [Hz]200.0
typeintchopper package selected sloppy chopper = 1, B chopper = 2, Gd chopper = 33


[ Identification | Description | Input parameters | Links ]

Generated on 2024-01-03 11:47:43

Last Modified: Tuesday, 16-Apr-2024 20:05:21 CEST
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