Two modes behavior of vortex oscillations in spin-transfer nanocontacts subject to in-plane magneticfields

Vortex oscillations induced by dc currents (Idc) through a metallic nanocontact subject to in-plane magnetic fields (Hext) are studied by measuring voltage power spectra. Two oscillations modes exist: at large Idc the oscillation frequency (fosc) is substantially insensitive to Hext, whereas at low Idc, fosc decreases with Hext increasing. At intermediate Idc the two modes coexist. This behavior is ascribed to the magnetic states of the device ferromagnetic layers: in the first mode vortices are formed in both layers while in the second mode one layer is in a vortex state while the other is in a quasiuniform state

Two modes behavior of vortex oscillations in spin-transfer nanocontacts subject to in-plane magnetic fields

Vortex oscillations induced by dc currents (Idc) through a metallic nanocontact subject to in-plane magnetic fields (Hext) are studied by measuring voltage power spectra. Two oscillations modes exist: at large Idc the oscillation frequency (fosc) is substantially insensitive to Hext, whereas at low Idc, fosc decreases with Hext increasing. At intermediate Idc the two modes coexist. This behavior is ascribed to the magnetic states of the device ferromagnetic layers: in the first mode vortices are formed in both layers while in the second mode one layer is in a vortex state while the other is in a quasiuniform state

International comparison of activity measurements of radon 222: EURAMET Project n°1475 – EURAMET.RI(II)-S8.Rn-222

International audienceAn international comparison of activity per unit volume of 222Rn (EURAMET project N° 1475, registered in KCDB as supplementary comparison EURAMET.RI(II)-S8.Rn-222) was organised in 2019 within the framework of the European project MetroRADON. The LNE-LNHB is the pilot of the comparison. Samples of 222Rn gas provided by the LNE-LNHB were sent to the participants and were measured using various techniques. The reference value is the power moderated mean (PMM) (Pommé, 2013) of the seven submitted results

Determination of the 151Sm half-life

New measurements have been undertaken to determine the half-life of 151Sm. A pure 151Sm solution was obtained after chemical separation from a samarium solution resulting from the dissolution of an irradiated samarium sample. The concentration of 151Sm in the solution was measured by mass spectrometry, combined with the isotope dilution technique. The activity of the solution was measured by liquid scintillation counting by six European laboratories as part of an international comparison. These combined results lead to a half-life of T1/2 = 94.6(6) a.JRC.D.4-Standards for Nuclear Safety, Security and Safeguard

Results of the EURAMET.RI(II)- S7.Sm-151 supplementary comparison (EURAMET Project 1292)

An international comparison of the activity standardisation of the relatively long-lived gamma-ray emitter 151Sm has been recently completed. A total of six laboratories measured a solution prepared by CEA/LNHB and CEA/LANIE. Aliquots of the master solution were standardized in terms of activity per mass unit by participant laboratories using 2 different techniques. The results of the comparison can be used as the basis for establishing equivalence among the laboratories. The activity measurements of this comparison are part of the joint research project “Metrology for Radioactive Waste Management” of the European Metrology Research Programme (EMRP). One aim of this project is a new determination of the 151Sm half-life.JRC.D.4-Standards for Nuclear Safety, Security and Safeguard