1. |
|
|
2. |
- Abolins, M., et al.
(författare)
-
The ATLAS Data Acquisition and High Level Trigger system
- 2016
-
Ingår i: Journal of Instrumentation. - 1748-0221. ; 11
-
Tidskriftsartikel (refereegranskat)abstract
- This paper describes the data acquisition and high level trigger system of the ATLAS experiment at the Large Hadron Collider at CERN, as deployed during Run 1. Data flow as well as control, configuration and monitoring aspects are addressed. An overview of the functionality of the system and of its performance is presented and design choices are discussed.
|
|
3. |
|
|
4. |
- Soloviev, A. A., et al.
(författare)
-
Fast electron generation using PW-class PEARL facility
- 2011
-
Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Saunders Elsevier. - 0168-9002 .- 1872-9576. ; 653:1, s. 35-41
-
Tidskriftsartikel (refereegranskat)abstract
- We use a PW-class PEARL facility to study fast electron beam generation during high intensity laser pulse interaction with a supersonic gas jet. We show that electron beams with several hundreds of MeV and relatively large charges, of hundreds of pC and more, can be effectively produced without any guiding structures. PIC simulations also confirm the obtained experimental data and provide optimized conditions of laser–plasma interaction for high-charged beam production.
|
|
5. |
- Ahlström, A. P., et al.
(författare)
-
Historically unprecedented global glacier decline in the early 21st century
- 2015
-
Ingår i: Journal of Glaciology. - 0022-1430 .- 1727-5652. ; 61:228, s. 745-
-
Tidskriftsartikel (refereegranskat)abstract
- Observations show that glaciers around the world are in retreat and losing mass. Internationally coordinated for over a century, glacier monitoring activities provide an unprecedented dataset of glacier observations from ground, air and space. Glacier studies generally select specific parts of these datasets to obtain optimal assessments of the mass-balance data relating to the impact that glaciers exercise on global sea-level fluctuations or on regional runoff. In this study we provide an overview and analysis of the main observational datasets compiled by the World Glacier Monitoring Service (WGMS). The dataset on glacier front variations (similar to 42 000 since 1600) delivers clear evidence that centennial glacier retreat is a global phenomenon. Intermittent readvance periods at regional and decadal scale are normally restricted to a subsample of glaciers and have not come close to achieving the maximum positions of the Little Ice Age (or Holocene). Glaciological and geodetic observations (similar to 5200 since 1850) show that the rates of early 21st-century mass loss are without precedent on a global scale, at least for the time period observed and probably also for recorded history, as indicated also in reconstructions from written and illustrated documents. This strong imbalance implies that glaciers in many regions will very likely suffer further ice loss, even if climate remains stable.
|
|
6. |
- Belotelov, V. I., et al.
(författare)
-
Magnetophotonic intensity effects in hybrid metal-dielectric structures
- 2014
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 89:4, s. 045118-
-
Tidskriftsartikel (refereegranskat)abstract
- The magneto-optical properties of a hybrid metal-dielectric structure consisting of a one-dimensional gold grating on top of a magnetic waveguide layer are studied experimentally and theoretically. It is demonstrated that a magnetic field applied in the longitudinal configuration (in the plane of the magnetic film and perpendicular to the slits in the gold grating) to the metal-dielectric structure modifies the field distribution of the optical modes and thus changes the mode excitation conditions. In the optical far field, this manifests in the alteration of the optical transmittance or reflectance when the structure becomes magnetized. This magneto-optical effect is shown to represent a novel class of effects related to the magnetic-field-induced modification of the Bloch modes of the periodic hybrid structure. That is why we define this effect as "longitudinal magnetophotonic intensity effect" (LMPIE). The LMPIE has two contributions, odd and even in magnetization. While the even LMPIE is maximal for the light polarized perpendicular to the grating slits (TM) and minimal for the orthogonal polarization (TE), the odd LMPIE takes maximum values at some intermediate polarization and vanishes for pure TM and TE polarizations. Two principal modes of the magnetic layer - TM and TE - acquire in the longitudinal magnetic field additional field components and thus turn into quasi-TM and quasi-TE modes, respectively. The largest LMPIE is observed for excitation of the antisymmetrical quasi-TE mode by TM-polarized light. The value of the LMPIE measured for the plasmonic structure with a magnetic film of Bi2Dy1Fe4Ga1O12 composition is about 1% for the even effect and 2% for the odd one. However, the plasmonic structure with a magnetic film with a higher concentration of bismuth (Bi2.97Er0.03Fe4Al0.5Ga0.5O12) gives significantly larger LMPIE: even LMPIE reaches 24% and odd LMPIE is 9%. Enhancement of the magneto-optical figure of merit (defined as the ratio of the specific Faraday angle of a magnetic film to its absorption coefficient) of the magnetic films potentially causes the even LMPIE to exceed 100% as is predicted by calculations. Thus, the nanostructured material described here may be considered as an ultrafast magnetophotonic light valve.
|
|
7. |
- Belotelov, V. I., et al.
(författare)
-
Plasmon-mediated magneto-optical transparency
- 2013
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 4, s. 2128-
-
Tidskriftsartikel (refereegranskat)abstract
- Magnetic field control of light is among the most intriguing methods for modulation of light intensity and polarization on sub-nanosecond timescales. The implementation in nanostructured hybrid materials provides a remarkable increase of magneto-optical effects. However, so far only the enhancement of already known effects has been demonstrated in such materials. Here we postulate a novel magneto-optical phenomenon that originates solely from suitably designed nanostructured metal-dielectric material, the so-called magneto-plasmonic crystal. In this material, an incident light excites coupled plasmonic oscillations and a waveguide mode. An in-plane magnetic field allows excitation of an orthogonally polarized waveguide mode that modifies optical spectrum of the magneto-plasmonic crystal and increases its transparency. The experimentally achieved light intensity modulation reaches 24%. As the effect can potentially exceed 100%, it may have great importance for applied nanophotonics. Further, the effect allows manipulating and exciting waveguide modes by a magnetic field and light of proper polarization.
|
|
8. |
- Toropov, A. A., et al.
(författare)
-
Magneto-photoluminescence studies of Cd(Mn)Se/Zn(Mn)Se diluted magnetic nanostructures
- 2001
-
Ingår i: Physica. E, Low-Dimensional systems and nanostructures. - 1386-9477 .- 1873-1759. ; 10:1-3, s. 362-367
-
Tidskriftsartikel (refereegranskat)abstract
- We report on cw and time-resolved photoluminescence (PL) studies of Cd(Mn)Se/Zn(Mn)Se diluted magnetic semiconductor nanostructures grown by molecular beam epitaxy. Excitonic PL intensity, decay time and Zeeman splitting have been studied systematically as a function of Cd(Mn)Se nominal thickness, Mn concentration and sample design. Wave function mapping has been performed, evidencing the formation of semi-magnetic quantum disk islands in the samples with thick enough Cd(Mn)Se insertions. ⌐ 2001 Elsevier Science B.V.
|
|
9. |
- Baikov, V. A., et al.
(författare)
-
Conservation laws for two-phase filtration models
- 2014
-
Ingår i: Communications in nonlinear science & numerical simulation. - : Elsevier. - 1007-5704 .- 1878-7274. ; 19:2, s. 383-389
-
Tidskriftsartikel (refereegranskat)abstract
- The paper is devoted to investigation of group properties of a one-dimensional model of two-phase filtration in porous medium. Along with the general model, some of its particular cases widely used in oil-field development are discussed. The Buckley-Leverett model is considered in detail as a particular case of the one-dimensional filtration model. This model is constructed under the assumption that filtration is one-dimensional and horizontally directed, the porous medium is homogeneous and incompressible, the filtering fluids are also incompressible. The model of "chromatic fluid" filtration is also investigated. New conservation laws and particular solutions are constructed using symmetries and nonlinear self-adjointness of the system of equations.
|
|
10. |
- Cantwell, C. D., et al.
(författare)
-
Nektar plus plus : An open-source spectral/hp element framework
- 2015
-
Ingår i: Computer Physics Communications. - : Elsevier BV. - 0010-4655. ; 192, s. 205-219
-
Tidskriftsartikel (refereegranskat)abstract
- Nektar++ is an open-source software framework designed to support the development of high-performance scalable solvers for partial differential equations using the spectral/hp element method. High-order methods are gaining prominence in several engineering and biomedical applications due to their improved accuracy over low-order techniques at reduced computational cost for a given number of degrees of freedom. However, their proliferation is often limited by their complexity, which makes these methods challenging to implement and use. Nektar++ is an initiative to overcome this limitation by encapsulating the mathematical complexities of the underlying method within an efficient C++ framework, making the techniques more accessible to the broader scientific and industrial communities. The software supports a variety of discretisation techniques and implementation strategies, supporting methods research as well as application-focused computation, and the multi-layered structure of the framework allows the user to embrace as much or as little of the complexity as they need. The libraries capture the mathematical constructs of spectral/hp element methods, while the associated collection of pre-written PDE solvers provides out-of-the-box application-level functionality and a template for users who wish to develop solutions for addressing questions in their own scientific domains. Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland No. of lines in distributed program, including test data, etc.: 1052456 No. of bytes in distributed program, including test data, etc.: 42851367 External routines: Boost, PFTW, MPI, BLAS, LAPACK and METIS (www.cs.umn.edu) Nature of problem: The Nektar++ framework is designed to enable the discretisation and solution of time-independent or time-dependent partial differential equations. Running time: The tests provided take a few minutes to run. Runtime in general depends on mesh size and total integration time.
|
|
11. |
- Suturin, S. M., et al.
(författare)
-
Role of gallium diffusion in the formation of a magnetically dead layer at the Y3Fe5O12/Gd3Ga5O12 epitaxial interface
- 2018
-
Ingår i: PHYSICAL REVIEW MATERIALS. - : AMER PHYSICAL SOC. - 2475-9953. ; 2:10
-
Tidskriftsartikel (refereegranskat)abstract
- We have clarified the origin of a magnetically dead interface layer formed in yttrium iron garnet (YIG) films grown at above 700 degrees C onto a gadolinium gallium garnet (GGG) substrate by means of laser molecular beam epitaxy. The diffusion-assisted formation of a Ga-rich region at the YIG/GGG interface is demonstrated by means of composition depth profiling performed by x-ray photoelectron spectroscopy, secondary ion mass spectroscopy, and x-ray and neutron reflectometry. Our finding is in sharp contrast to the earlier expressed assumption that Gd acts as a migrant element in the YIG/GGG system. We further correlate the presence of a Ga-rich transition layer with considerable quenching of ferromagnetic resonance and spin wave propagation in thin YIG films. Finally, we clarify the origin of the enigmatic low-density overlayer that is often observed in neutron and x-ray reflectometry studies of the YIG/GGG epitaxial system.
|
|
12. |
|
|
13. |
- Yakovlev, S. L., et al.
(författare)
-
Asymptotic Solution of A Multichannel Scattering Problem with A Nonadiabatic Coupling
- 2018
-
Ingår i: Theoretical and mathematical physics. - 0040-5779 .- 1573-9333. ; 195:3, s. 874-885
-
Tidskriftsartikel (refereegranskat)abstract
- We consider a multichannel scattering problem in an adiabatic representation. We assume that the nonadiabatic coupling matrix has a nontrivial value at large internuclear separations, and we construct asymptotic solutions at large internuclear distances. We show that these solutions up to the first order of the perturbation theory are identical to the asymptotic solutions of the reprojection approach, which was previously proposed as a means for solving the electron translation problem in the context of the Born-Oppenheimer method.
|
|
14. |
- Castillo Tapia, Pilar, et al.
(författare)
-
Mode propagation in glide-symmetric dielectric-filled corrugated waveguides
- 2021
-
Ingår i: 2021 IEEE International Symposium on Antennas and Propagation and North American Radio Science Meeting, APS/URSI 2021 - Proceedings. - : Institute of Electrical and Electronics Engineers Inc.. ; , s. 1984-1985
-
Konferensbidrag (refereegranskat)abstract
- Glide symmetry in periodic structures introduces several advantages such as low dispersion, wider stopbands, and higher levels of anisotropy. Here, we propose the use of glide symmetry in dielectric-filled corrugated rectangular waveguides. The operation of these filled waveguides is studied by means of a multimodal transfer-matrix approach that carries out a Bloch analysis of the corresponding unit cell to obtain the dispersion diagram of the structure (both the phase shift and the attenuation rate). In this specific configuration, glide symmetry is found to provide a wider backward passband below the cutoff of the non-corrugated housing waveguide.
|
|
15. |
- Rajaei, Hossein, et al.
(författare)
-
Catalogue of the lepidoptera of Iran
- 2023
-
Ingår i: Integrative Systematics. - : Stuttgart State Museum of Natural History. - 2628-2380. ; 6:SP1, s. 121-459
-
Tidskriftsartikel (refereegranskat)
|
|
16. |
- Volkov, Mikhail Vladimirovich, et al.
(författare)
-
Adiabatic versus diabatic approach to multichannel Coulomb scattering for mutual neutralisation reaction H+ + H- -> H*(2) -> H(1) + H(n)
- 2015
-
Ingår i: Chemical Physics. - : Elsevier BV. - 0301-0104 .- 1873-4421. ; 462, s. 57-64
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper it is demonstrated that the split-potential driven Schrodinger approach to two-body Coulomb multichannel quantum scattering in a diabatic framework presented by us in a previous paper (Volkov et al., 2011) also can be formulated within an adiabatic framework. The new formulation of the theory is numerically realised using finite element discrete variable representation. The method is applied to a realistic model of the fundamental mutual neutralisation reaction H+ + H- -> H*(2) -> H(1) + H(n) described in terms of the seven lowest (1)Sigma(+)(g) electronic states of the H-2 molecule. The obtained cross sections are in good agreement with other methods applied to the same model.
|
|
17. |
- Volkov, M. V., et al.
(författare)
-
Investigation of scattering processes in quantum few-body systems involving long-range interaction by the complex-rotation method
- 2013
-
Ingår i: Physics of Atomic Nuclei. - 1063-7788 .- 1562-692X. ; 76:2, s. 188-195
-
Tidskriftsartikel (refereegranskat)abstract
- The complex-rotation method adapted to solving the multichannel scattering problem in the two-body system where the interaction potential contains the long-range Coulomb components is described. The scattering problem is reformulated as the problem of solving a nonhomogeneous Schrodinger equation in which the nonhomogeneous term involves a Coulomb potential cut off at large distances. The incident wave appearing in the nonhomogeneous term is a solution of the Schrodinger equation with longrange Coulomb interaction. This formulation is free from approximations associated with a direct cutoff of Coulomb interaction at large distances. The efficiency of this formalism is demonstrated by considering the example of solving scattering problems in the alpha-alpha and p-p systems.
|
|
18. |
- Volkov, Mikhail V., et al.
(författare)
-
Potential splitting approach to multichannel Coulomb scattering : The driven Schrodinger equation formulation
- 2011
-
Ingår i: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947 .- 1094-1622. ; 83:3, s. 032722-
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper we suggest an approach for the multichannel Coulomb scattering problem. The Schrodinger equation for the problem is reformulated in the form of a set of inhomogeneous equations with a finite-range driving term. The boundary conditions at infinity for this set of equations have been proven to be purely outgoing waves. The formulation presented here is based on splitting the interaction potential into a finite-range core part and a long-range tail part. The conventional matching procedure coupled with the integral Lippmann-Schwinger equations technique is used in the formal theoretical basis of this approach. The reformulated scattering problem is suitable for application in the exterior complex scaling technique: the practical advantage is that after complex scaling, the problem is reduced to a boundary problem with zero boundary conditions. The Coulomb wave functions are used only at a single point; if this point is chosen to be at a sufficiently large distance, on using the asymptotic expansion of Coulomb functions, one may completely avoid the Coulomb functions in the calculations. The theoretical results are illustrated with numerical calculations for two models.
|
|