0000000000460525

AUTHOR

Jens Jensen

showing 3 related works from this author

Energy-loss straggling of 2-10 MeV/u Kr ions in gases

2013

Measurements have been performed on a time-of-flight setup at the Jyväskylä K130 cyclotron, aiming at energy-loss straggling of heavy ions in gases. Theoretical predictions based on recently developed theory as well as an empirical interpolation formula predict that straggling can be more than ten times higher than Bohr straggling in the MeV/u regime. Our measurements with up to 9.3 MeV/u Kr ions on He, N2, Ne and Kr targets confirm this feature. Our calculations show the relative contributions of linear straggling, bunching including packing, and charge exchange. Our results for stopping cross sections are compatible with values from the literature. Funding Agencies|EU||Academy of Finland …

PhysicsEnergy lossCyclotronPhysics::Medical Physics7. Clean energy01 natural sciencesAtomic and Molecular Physics and Optics010305 fluids & plasmaslaw.inventionIonBohr modelNuclear physicssymbols.namesakelawAtomic and Molecular CollisionsTeknik och teknologier0103 physical sciencessymbolsEngineering and TechnologyAtomic physics010306 general physicsAtomien ja molekyylien törmäyksetCharge exchange
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Energy loss and straggling of MeV Si ions in gases

2017

We present measurements of energy loss and straggling of Si ions in gases. An energy range from 0.5 to 12 MeV/u was covered using the 6 MV EN tandem accelerator at ETH Zurich, Switzerland, and the K130 cyclotron accelerator facility at the University of Jyväskylä, Finland. Our energy-loss data compare well with calculation based on the SRIM and PASS code. The new straggling measurements support a pronounced peak in He gas at around 4 MeV/u predicted by recent theoretical calculations. The straggling curve structure in the other gases (N2, Ne, Ar, Kr) is relatively flat in the covered energy range. Although there is a general agreement between the straggling data and the theoretical calculat…

Nuclear and High Energy PhysicsRange (particle radiation)Energy lossta114Chemistryenergy lossPhysics::Medical PhysicsCyclotronTandem acceleratorcharge exchangeenergy-loss stragglingIonlaw.inventionNuclear physicslawAtomic physicsInstrumentationCharge exchangeNuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
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Experimental and theoretical investigation of Cr1-xScxN solid solutions for thermoelectrics

2016

The ScN- and CrN-based transition-metal nitrides have recently emerged as a novel and unexpected class of materials for thermoelectrics. These materials constitute well-defined model systems for investigating mixing thermodynamics, phase stability, and band structure aiming for property tailoring. Here, we demonstrate an approach to tailor their thermoelectric properties by solid solutions. The trends in mixing thermodynamics and densities-of-states (DOS) of rocksalt-Cr1-xScxN solid solutions (0 ≤ x ≤ 1) are investigated by first-principles calculations, and Cr1-xScxN thin films are synthesized by magnetron sputtering. Pure CrN exhibits a high power factor, 1.7 × 10−3 W m−1 K−2 at 720 K, en…

Condensed matter physicsChemistryGeneral Physics and Astronomy02 engineering and technology021001 nanoscience & nanotechnologyThermoelectric materials01 natural sciencesDelocalized electronElectrical resistivity and conductivitySeebeck coefficient0103 physical sciencesThermoelectric effectThin film010306 general physics0210 nano-technologyElectronic band structureSolid solutionJournal of Applied Physics
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