GR1(A) + software Kromek

The Kromek GR1 is a high-performance gamma-ray spectrometer utilizing a 1cm³ CZT detector. It is completely self-contained, with built-in preamplifier, shaping amplifier, baseline restorer, pulse height digitizer, and HV supply.

The GR1 only uses USB power supply. Optional PEO delivers the GR1 with Windows tablet.

Free software K-Spect

GR1 and GR1A – Kromek + MultiSpec software

The CZT spectrometer GR1 from Kromek is available with free K-Spect software and optionally expandable with the advanced MultiSpect software.

Advanced model GR1-A

in-Situ monitoring

The GR1-A is the advanced version of the GR1.
With extra inputs and outputs the operational flexibility is even greater.
The GR1-A has been specially developed for specific applications in nuclear research and scientific research (see below).

GR1 application and subject areas:

Nuclear safety

  • medical;
  • industry;
  • safety services;
  • laboratories;
  • radiation safety;
  • in-Situ monitoring;
  • nucleair spectroscopy;
  • nucleair industry.


  • high spectral resolution;
  • high efficiency;
  • easy to use;
  • minimal power supply;
  • multi-spectra display (GR1-A).


  • super compact;
  • energy resolution: <2,5% FWHM @ 662 keV;
  • K-Spect software;
  • CZT semiconductor detector (1x1x1 cm);
  • energy range: 30 keV to 3 MeV;
  • extensive nuclide library (416 isotopes);
  • MCX -connection (GR1-A);
  • MCA gate input (GR1-A);
  • timing output (GR1-A);
  • MultiSpect software (GR1-A).

CZT: high resolution spectroscopy at room temperature

CZT (Cadmium Zink Telluride) is a room temperature semiconductor that directly converts x-ray or gamma-ray photons into electrons. CZT is a unique semiconductor compared with other scintillator detectors, in that CZT operates at room temperature and can process >10 million photons /second/mm². Additionally, CZT’s spectroscopic resolution (2%) clearly out performs any commercially available scintillator detector on price/quality.

How does it work?

CZT detectors are fabricated with very thin metalized electrode geometries deposited on the detector surfaces. These electrodes are then electrically biased creating a difference in electrical potential within the detector volume. When ionizing radiation interacts with the CZT crystal, electron hole pairs are created in proportion to the energy of the incoming radiation.

The negatively charged electrons and positively charged holes then migrate to the oppositely charged electrode where they are collected. The resulting charge pulse is then detected by the preamplifier, which produces a voltage pulse whose height is proportional to the incident energy of the incoming photon. The signal from the preamplifier is then fed into a shaping amplifier that converts the signal into a Gaussian pulse and amplifies it. The signal can then be fed into a standard counting system or Multi Channel Analyzer (MCA) to generate the characteristic spectrum for the incoming photons.

 CZT versus NaI resolution

CZT versus similar spectroscopic detectors

Source: Gamma-ray detectors for non-destructive analyses, P.A. Russo and D.T. Vo (read full article here)
*CZT-detector from Kromek

Wilt u meer weten over de GR1 product serie?
Download de GR1 datasheet of neem contact op met één van onze productspecialisten.

Also read: CZT-based products available at PEO

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Vichi, S., Infantino, A., Cicoria, G., Pancaldi, D., Mostacci, D., Lodi, F., & Marengo, M. (2016). An innovative gamma-ray spectrometry system using a compact and portable CZT detector for radionuclidic purity tests of PET radiopharmaceuticals. Radiation Effects and Defects in Solids Incorporating Plasma Science and Plasma Technology, 171(9-10), 726-735. doi:10.1080/10420150.2016.1253090

CZT detectorradionuclidic purityquality controlradiopharmaceuticals




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