| 1. |
- Fernandez, J. L. Abelleira, et al.
(författare)
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A Large Hadron Electron Collider at CERN
- 2012
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Ingår i: Journal of Physics G. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 39:7
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Tidskriftsartikel (refereegranskat)
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| 2. |
- Bugaev, K. A., et al.
(författare)
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Going beyond the second virial coefficient in the hadron resonance gas model
- 2018
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Ingår i: Nuclear Physics A. - : ELSEVIER SCIENCE BV. - 0375-9474 .- 1873-1554. ; 970, s. 133-155
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Tidskriftsartikel (refereegranskat)abstract
- We develop a novel formulation of the hadron resonance gas model which, besides a hard-core repulsion, explicitly accounts for the surface tension induced by the interaction between the particles. Such an equation of state allows us to go beyond the Van der Waals approximation for any number of different hard-core radii. A comparison with the Carnahan Starling equation of state shows that the new model is valid for packing fractions 0.2-0.22, while the usual Van der Waals model is inapplicable at packing fractions above 0.1-0.11. Moreover, it is shown that the equation of state with induced surface tension is softer than the one of hard spheres and remains causal at higher particle densities. The great advantage of our model is that there are only two equations to be solved and neither their number nor their form depend on the values of the hard-core radii used for different hadronic resonances. Such an advantage leads to a significant mathematical simplification compared to other versions of truly multi-component hadron resonance gas models. Using this equation of state we obtain a high-quality fit of the ALICE hadron multiplicities measured at the center-of-mass energy 2.76 TeV per nucleon and we find that the dependence of chi(2)/ndf on the temperature has a single global minimum in the traditional hadron resonance gas model with the multi-component hard-core repulsion. Also we find two local minima of chi(2)/ndf in the model in which the proper volume of each hadron is proportional to its mass. However, it is shown that in the latter model a second local minimum located at higher temperatures always appears far above the limit of its applicability. (C) 2017 Elsevier B.V. All rights reserved.
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| 3. |
- Johansson, Martin, et al.
(författare)
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SLAC FACET-II positron damping ring magnet design
- 2016
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Ingår i: IPAC 2016 - Proceedings of the 7th International Particle Accelerator Conference. - 9783954501472 ; , s. 1154-1156
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Konferensbidrag (refereegranskat)abstract
- The FACET-II facility, currently being designed at SLAC, will contain a small 20 m circumference, 335 MeV, positron damping ring. The ring has to fit in the existing linac tunnel, meaning that a compact lattice with short distances between magnets is required. The detailed magnet design is done in Opera-3d, with a finite element model of a full damping ring arc being simulated. This article presents this magnet design in a relatively early stage, with iteration between magnet and lattice design currently in progress.
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| 4. |
- Yakimenko, Iryna, et al.
(författare)
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Bound states, electron localization and spin correlations in low-dimensional GaAs/AlGaAs quantum constrictions
- 2013
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Ingår i: Journal of Physics. - : Institute of Physics Publishing (IOPP). - 0953-8984 .- 1361-648X. ; 25:7, s. 072201-
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Tidskriftsartikel (refereegranskat)abstract
- We analyze the occurrence of local magnetization and the effects of electron localization in different models of quantum point contacts (QPCs) using spin-relaxed density functional theory (DFT/LSDA) by means of numerical simulations. In the case of soft confinement potentials the degree of localization is weak and we therefore observe only traces of partial electron localization in the middle of the QPC. In the pinch-off regime there is, however, distinct accumulation at the QPC edges. At the other end, strong confinement potential, low-electron density in the leads and top or implant gates favor electron localization. In such cases one may create a variety of electron configurations from a single localized electron to more complex structures with multiple rows and Wigner lattices.
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