Power-Meter for Soft X-Ray Radiation
Absolute Measuring Instrument of Power on the Basis of High-Temperature Superconducting Thermometer as the Primary Standard Detector for Soft X-Ray Synchrotron Radiation
Tech Area / Field
- INF-SIG/Sensors and Signal Processing/Information and Communications
- INS-MEA/Measuring Instruments/Instrumentation
- PHY-SSP/Solid State Physics/Physics
8 Project completed
Senior Project Manager
Tyurin I A
Vavilov State Optical Institute (GOI), Russia, St Petersburg
- Budker Institute of Nuclear Physics, Russia, Novosibirsk reg., Akademgorodok\nVNIIEF, Russia, N. Novgorod reg., Sarov
- Universite de Caen / Groupe de Recherche en Informatique, Image, Automatique et Instrumentation de Caen, France, Caen\nLaboratoire National Henri Becquerel, France, Gif-sur-Yvette Cedex\nPhysikalisch-Technische Bundesanstalt / Laboratory of X-ray Radiometry, Germany, Berlin
Project summaryPurposes of the project
The purpose of the project is creation of a pilot model and preliminary certification of an absolute measuring instrument for soft X-ray synchrotron radiation power in the range from 150 up to 3000 eV (8 – 0.4 nm). The suggested absolute measuring instrument for X-ray power (AMIX) can be considered as a primary standard detector for calibration of any other types of detectors and investigation of optical properties of materials in soft X-ray range.
Staff in the field of research
Despite of few successful examples of the precision detectors development for the X-ray range of 150 – 3000 eV, the nomenclature of such detectors is rather limited, and the task of development of absolute detectors as primary standards for performance of metrology measurements both on SR and on other sources of radiation remains to be actual.
One of the ways of absolute registration of incident radiation power is transformation of radiant energy to the thermal one with subsequent measurement of the working element temperature. The present project suggests creation of liquid nitrogen-cooled absolute measuring instrument for X-ray power with electrical substitution of radiation power incident on it and with high-temperature superconducting (HTS) film to measure the temperature. The closest analogue for the suggested device is a radiometer cooled by liquid helium with electrical-substitution of radiation power and semiconductor temperature sensor (Synchrotron Radiation Electrical Substitution Radiometer - SYRES), which is successfully applied now at the synchrotron radiation source BESSY-2 by the PTB group (Berlin, Germany) to register soft X-ray radiation of a power not less than 1 mW accurate to 0.2% [1-3].
Influence of the project on progress in the given area
Thus, performance of the project will give a solution for one of the most actual problems of the modern metrology in the soft X-rays range, i.e. creation of a primary standard of the instrument to measure radiation power, which would allow one to carry out absolute calibration of secondary standards – detectors of any types which are now widely used in study of high-temperature plasma, physics of the Sun and other important directions connected with registration of soft X-ray radiation.
Competence of project participants
Authors of the project have rather extensive experience in designing and manufacturing reception devices on the basis of HTS bolometers for infrared area of spectrum, as well as in research of spectral and time parameters of X-ray radiation detectors with the use of synchrotron radiation and research of X-ray radiation interaction with condensed media. A number of their works on the specified questions are published. One of the results of performance of the project will be - the association of the existing technology of HTS bolometers with the techniques of detection and diagnostics of soft X-ray radiation.
Expected results and their application
The project will result in development of an absolute measuring instrument for X-ray radiation power with a sensitivity not worse than that of the foreign analogue for SR, (SYRES, Germany). However, our device has the better time characteristics and is cheaper in operation due to cooling with liquid nitrogen.
Soft X-ray radiation influence on the structural, noise and degradation properties of HTS films will be researched in the course of creation of the device.
The pilot model made as a result of the project will be mounted in Budker INP SB RAS on the metrology station stand using SR for absolute metrological calibrations for Russian and foreign organizations in the framework of international cooperation.
Expected characteristics of absolute measuring instrument of the power:
Spectral range 150 – 3000 eV (8 – 0.4 nm)
Operation temperature 85 – 90 K
Time constant 0.1 – 0.05 s
Equivalent noise power (NEP) 1.2 ґ 10–11 – 3.8 ґ 10-12 W/Hz1/2
Accuracy of measurements 0.2 – 1% at power of 1 mW
ISTC goals to be achieved
The suggested project meets completely meets ISTC goals since it allows scientists and other specialists occupied earlier in weapon development and manufacture to use their qualification in solution of applied problems of non-military orientation.
Scope of the work
Within the framework of the project it is supposed to carry out:
- Computational modeling of various operating modes of the AMIX and estimation of achievable parameters;
- Development of production methods for separate units of the AMIX;
- Manufacturing of the AMIX pilot model;
- Development and creation of the control electronics;
- Manufacture of stands for preliminary certification of the AMIX on pulsed sources of X-ray radiation at VNIIEF;
- Research of soft X-ray radiation influence on the properties of HTS films;
- Measurements of spectral, temporal and threshold parameters of the pilot AMIX model on pulsed sources of X-ray radiation at VNIIEF;
- Installation and carrying out of preliminary tests of the AMIX on a synchrotron radiation source at Budker INP.
Role of foreign collaborators
The foreign collaborator Dr. Gerhard Ulm (Germany) is a well-known expert will take part in developing main decisions of the project, connected with the methods of calibration on SR and discussion of the results obtained, in providing the cooperation of his organization in testing on the SR beam. His participation will be reflected in joint publications.
The foreign collaborator - Prof. Didier Robbes (France) is a well-known expert on HTS bolometers and radiometric measurements based on the use of different thermometers of HTS films and uncooled film materials. He will take part in the general support of the project and its discussion, development of main decisions, analysis of the suggested construction of the absolute power measuring instrument on the basis of HTS thermometer as a standard detector for soft X-ray synchrotron radiation. He will discuss the results of investigations obtained in the course of the project. His participation may be reflected in joint publications.
The foreign collaborator - Prof. Patrick E. Phelan (USA) a well-known expert on thermal processes in thin films at cryogenic temperatures, will take part in the general support of the project, in the discussion of how it is carried out, in analysis of results of thermophysical calculations and experiments at development of the absolute measuring instrument for SR power, and in the estimation of influence of electrical substitution equivalence on device accuracy. He will take part in the statement of investigations and analysis of the results obtained. Possible, his participation will be reflected in joint publications.
The foreign collaborator - Prof. Laszlo B. Kish (USA) a well-known expert on noise problems, will take part in the general support of the project, in its discussion, in development of basic decisions, in analysis of the noise and degradation parameters of epitaxial HTS films at interaction with soft X-ray synchrotron radiation, in definition of the set and parameters of diagnostic methods to be used. He will take part in the statement of research and analysis of the results obtained. His participation will be reflected in joint publications.
Methodology and scientific and technical approaches
The operating principle of the absolute measuring instrument for SR power consists in the following: X-ray photons, being absorbed in the substance of the substrate, transfer their power to it as thermal power which is in turn replaced by the electrical power of the heater. High sensitivity of the AMIX is achieved due to the high temperature coefficient of resistance of the HTS film and low level of noise in the superconducting transition region at liquid nitrogen temperatures.
The active negative electrothermal feedback mode will be used for reduction of the time constant, expansion of the dynamic range and improvement of temperature stability of the HTS thermometer.
The influence of equivalence of substitution of absorbed SR power with that of the heater, instability of temperature in the cryostat, and the level of excessive flicker-noise of the HTS film on the AMIX accuracy will be investigated.
In the course of research of SR influence on the properties of epitaxial HTS films, the structural characteristics will be investigated, the frequency and temperature dependence of excess flicker noise will be measured in the temperature range of 77-300 K and frequency range of 1 Hz - 10 kHz, before and after impact of X-ray radiation.
In the course of estimation of AMIX efficiency as a standard detector for X-ray radiation the following will be investigated and taken into account: total external reflection, penetration of radiation through the substrate and photo-stimulated electron emission from the receiving surface of the sensitive element.
Research of soft X-rays influence on properties of HTS films, measurements of temporal and spectral characteristics of the pilot AMIX model will be carried out using X-rays sources of VNIIEF and Budker INP SB RAS.
Preliminary tests of the AMIX on synchrotron radiation are supposed to be carried out on the VEPP-3 storage ring at Budker INP SB RAS.
The International Science and Technology Center (ISTC) is an intergovernmental organization connecting scientists from Kazakhstan, Armenia, Tajikistan, Kyrgyzstan, and Georgia with their peers and research organizations in the EU, Japan, Republic of Korea, Norway and the United States.
ISTC facilitates international science projects and assists the global scientific and business community to source and engage with CIS and Georgian institutes that develop or possess an excellence of scientific know-how.