Articles (en)

World Metrology Day 2019


World Metrology Day is an annual celebration of the signature of the Metre Convention on 20 May 1875 by representatives of seventeen nations.

Metrology, the science of measurement, plays a central role in scientific discovery and innovation, industrial manufacturing and international trade, in improving the quality of life and in protecting the global environment.

The theme for World Metrology Day 2019 is: The International System of Units – Fundamentally better. This theme was chosen because in November 2018, the General Conference on Weights and Measures agreed one of the largest changes to the International System of Units (the SI) since its inception…
(source BIPM and OIML)

More information on World Metrology Day website.

World Metrology Day 2018


World Metrology Day is an annual celebration of the signature of the Metre Convention on 20 May 1875 by representatives of seventeen nations.

Metrology, the science of measurement, plays a central role in scientific discovery and innovation, industrial manufacturing and international trade, in improving the quality of life and in protecting the global environment.

The theme for World Metrology Day 2018 is Constant evolution of the International System of Units. This theme was chosen because in November 2018, the General Conference on Weights and Measures is expected to agree one of the largest changes to the International System of Units (the SI) since its inception…
(source BIPM and OIML)

More information on World Metrology Day website.

Revision of the SI

At its 25th meeting (November 2014) the CGPM adopted a Resolution on the future revision of the International System of Units. This Resolution built on the CGPM’s previous Resolution (2011), which took note of the CIPM’s intention to propose a revision of the SI and set out a detailed roadmap towards the future changes.

In the revised SI four of the SI base units – namely the kilogram, the ampere, the kelvin and the mole – will be redefined in terms of constants; the new definitions will be based on fixed numerical values of the Planck constant (h), the elementary charge (e), the Boltzmann constant (kB), and the Avogadro constant (NA), respectively. Further, the definitions of all seven base units of the SI will also be uniformly expressed using the explicit-constant formulation, and specific mises en pratique will be drawn up to explain the realization of the definitions of each of the base units in a practical way.
(source BIPM)

More information on the BIPM website.

Marie Curie 150 years (1867-2017)

Born 150 years ago in Poland, Marie Curie was the first woman to teach in higher education, but above all she was the only one to receive two Nobel Prizes: the first in physics in 1903, with her husband Pierre, and the second in chemistry in 1911.
She manufactured and certified the first radium standard and, during the First World War, she contributed to the development of medical imaging by setting up radiological cars that travelled across the battlefields to detect shrapnel from wounded soldiers.
She perfectly represents all the perseverance and skill needed to study radioactivity and its applications.

Find some information about her life in the following links:
A short biography on Franceinfo.fr: Marie Curie, the first woman to win a Nobel Prize (fr)
An article by Bert M. Coursey in Applied Radiation and Isotopes: A reflection on the 150th anniversary of the birth of Marie Curie
On francetvéducation.fr: Curies’ first research on radioactivity (fr)
On FranceInter.fr: Sur les épaules de Darwin – Discovering radioactivity (March 26, 2016 broadcast)
Check out the Curie Museum’s 2017/2018 cultural programme dedicated to the 150th anniversary of Marie Curie.
First report by Marie Curie to the Académie des sciences on April 12, 1898: Radiation emitted by uranium and thorium compounds (fr)

Q spectrometry

Background
Isotopic analysis of actinides is commonly used in the nuclear fuel cycle or for the control of the Nuclear Non-Proliferation Treaty. Current conventional techniques, mass and alpha spectrometry, are sometimes limited by spectral interferences. The objective is therefore to develop a new technique for the analysis of total decay energy by spectrometry. Thanks to the high resolution of the magnetic calorimeters developed at LNHB, it will be possible to distinguish and quantify all alpha-emitting actinides present.

Achievements
A prototype magnetic calorimeter was developed and tested with a 210Po electro-deposited source integrated into a silver absorber. The measurement of the spectrum of total decay energy was obtained in the 10 mK dilution refrigerator.

Major results
The spectrum obtained showed a resolution of 0.9 keV at an energy of 5.4 MeV, a resolution one order of magnitude better than that of a semiconductor alpha detector. This detector thus offers one of the best performance in the world in terms of resolution.
The aim is now to demonstrate performance on mixtures of actinides and to simplify the integration of sources in absorbers in order to bring this technique towards a competitive use compared to the usual techniques.