MMR Technologies

Micro Cooler for X-Ray

MMR's Model K20XR is a compact thermal stage designed for variable-temperature studies of solid and powder samples in a variety of X-ray diffractometer systems. This thermal stage allows collection of X-ray diffraction data over a range of angles close to 90° in either horizontal or vertical mounting positions. By sliding the beryllium window up the body of the chamber, the sample, mounted in a sealed capillary on the cold stage, can be aligned optically with the beam. The window is then slid back into place and the chamber evacuated.


This system includes a unique X-ray diffraction vacuum chamber, a Joule-Thomson refrigerator, a sophisticated programmable temperature controller with intelligent keyboard/display, an accessory kit for beam blocking and attenuation of unwanted scattered X-rays, and an accessory kit required for operation with nitrogen gas over the temperature range of 70K to 730K.


Additional requirements include 99.998% pure nitrogen gas, a gas pressure regulator to deliver gas at 1800 psi (122 atm), and a vacuum pump to provide vacuum insulation (5 mTorr) of the refrigerator and sample in the vacuum chamber. The intelligent keyboard/display allows temperature to be set, read and ramped from one temperature to another. A computer is required to interface (RS-232C or IEEE 488) to the programmable temperature controller for software control of temperature and data acquisition.


  • Cylindrical Beryllium Window: Slides out of the way, allows easy alignment of sample
  • Sample-mounting Spring Clip: Accommodates sample capillaries of various sizes
  • Compact Size: Easily mounted in a goniometer, can be rotated during measurements
  • Operating Temperature: 80 K to 730 K
  • Temperature Stability: ±0.1 K with K-20 Programmable Controller
  • Temperature Response: 1 K/sec
  • Cooling Capacity: 250 mW at 85 K with nitrogen; 500 mW with Ar at 90 K
  • Cold pad size: 14 mm x 10 mm
  • Gas Consumption: 2.0 liters/min (STP)
  • Operating Pressure: 1800 psia
  • Weight of Cold Stage: 170g (6 oz)