1. |
|
|
2. |
- Abbondanno, U, et al.
(författare)
-
The data acquisition system of the neutron time-of-flight facility n_TOF at CERN
- 2005
-
Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 538:1-3, s. 692-702
-
Tidskriftsartikel (refereegranskat)abstract
- The n_TOF facility at CERN has been designed for the measurement of neutron capture, fission and (n, xn) cross-sections with high accuracy. This requires a flexible and-due to the high instantaneous neutron flux-almost dead time free data acquisition system. A scalable and versatile data solution has been designed based on 8-bit flash-ADCs with sampling rates up to 2 GHz and 8 Mbyte memory buffer. The software is written in C and C++ and is running on PCs equipped with RedHat Linux.
|
|
3. |
- Litaudon, X., et al.
(författare)
-
Development of steady-state scenarios compatible with ITER-like wall conditions
- 2007
-
Ingår i: Plasma Physics and Controlled Fusion. - 0741-3335 .- 1361-6587. ; 49:12B, s. B529-B550
-
Tidskriftsartikel (refereegranskat)abstract
- A key issue for steady-state tokamak operation is to determine the edge conditions that are compatible both with good core confinement and with the power handling and plasma exhaust capabilities of the plasma facing components (PFCs) and divertor systems. A quantitative response to this open question will provide a robust scientific basis for reliable extrapolation of present regimes to an ITER compatible steady-state scenario. In this context, the JET programme addressing steady-state operation is focused on the development of non-inductive, high confinement plasmas with the constraints imposed by the PFCs. A new beryllium main chamber wall and tungsten divertor together with an upgrade of the heating/fuelling capability are currently in preparation at JET. Operation at higher power with this ITER-like wall will impose new constraints on non-inductive scenarios. Recent experiments have focused on the preparation for this new phase of JET operation. In this paper, progress in the development of advanced tokamak (AT) scenarios at JET is reviewed keeping this long-term objective in mind. The approach has consisted of addressing various critical issues separately during the 2006-2007 campaigns with a view to full scenario integration when the JET upgrades are complete. Regimes with internal transport barriers (ITBs) have been developed at q(95) similar to 5 and high triangularity, 3 (relevant to the ITER steady-state demonstration) by applying more than 30 MW of additional heating power reaching beta(N) similar to 2 at B(o) similar to 3.1 T. Operating at higher 6 has allowed the edge pedestal and core densities to be increased pushing the ion temperature closer to that of the electrons. Although not yet fully integrated into a performance enhancing ITB scenario, Neon seeding has been successfully explored to increase the radiated power fraction (up to 60%), providing significant reduction of target tile power fluxes (and hence temperatures) and mitigation of edge localized mode (ELM) activity. At reduced toroidal magnetic field strength, high beta(N) regimes have been achieved and q-profile optimization investigated for use in steady-state scenarios. Values of beta(N) above the 'no-wall magnetohydrodynamic limit' (beta(N) similar to 3.0) have been sustained for a resistive current diffusion time in high-delta configurations (at 1.2 MA/1.8 T). In this scenario, ELM activity has been mitigated by applying magnetic perturbations using error field correction coils to provide ergodization of the magnetic field at the plasma edge. In a highly shaped, quasi-double null X-point configuration, ITBs have been generated on the ion heat transport channel and combined with 'grassy' ELMs with similar to 30 MW of applied heating power (at 1.2 MA/2.7 T, q(95) similar to 7). Advanced algorithms and system identification procedures have been developed with a view to developing simultaneously temperature and q-profile control in real-time. These techniques have so far been applied to the control of the q-profile evolution in JET AT scenarios.
|
|
4. |
|
|
5. |
- Cortes-Perez, O., et al.
(författare)
-
Bragg difraction of optical guided waves by spin-dipole waves in double layer ferromagnetic wave guides
- 2008
-
Ingår i: Revista mexicana de física. - 0035-001X. ; 54:5, s. 376-381
-
Tidskriftsartikel (refereegranskat)abstract
- The peculiarities of the Bragg diffraction of optical guided waves (OGWs) by spin-dipole waves (SDWs) in a new ferrite heterostructure, based on Bi3Fe5O12(BIG) thin film deposited on a standard YIG/GGG (a Yttrium Iron Garnet thin film over a Galium Gadolinum Garnet substrate) sample, is presented. It is shown that the efficiency of waveguide magnetooptic interaction between OGWs and SDWs in BIG/YIG/GGG can be 4-14 times larger than in the standard YIG/GGG waveguide, even in the case when the interacting waves are localized in YIG waveguide layer.
|
|
6. |
- Cortés-Pérez, O., et al.
(författare)
-
Difracción de Bragg de ondas ópticas guiadas por ondas de dipolo de spin en guías de onda ferromagnéticas de doble capa
- 2008
-
Ingår i: Revista Mexicana de Fisica. - 0035-001X. ; 54:5, s. 376-381
-
Tidskriftsartikel (refereegranskat)abstract
- The peculiarities of the Bragg diffraction of optical guided waves (OGWs) by spin-dipole waves (SDWs) in a new ferrite heterostructure, based on Bi3Fe5O12(BIG) thin film deposited on a standard YIG/GGG (a Yttrium Iron Garnet thin film over a Galium Gadolinum Garnet substrate) sample, is presented. It is shown that the efficiency of waveguide magnetooptic interaction between OGWs and SDWs in BIG/YIG/GGG can be 4-14 times larger than in the standard YIG/GGG waveguide, even in the case when the interacting waves are localized in YIG waveguide layer.
|
|
7. |
|
|
8. |
- Franco, R, et al.
(författare)
-
Partners for adenosine A1 receptors
- 2005
-
Ingår i: Journal of molecular neuroscience : MN. - 0895-8696. ; 26:2-3, s. 221-231
-
Tidskriftsartikel (refereegranskat)
|
|
9. |
|
|
10. |
- Garcia-Cortes, Alberto, et al.
(författare)
-
Raman scattering and Nd3+ laser operation in NaLa(WO4)(2)
- 2007
-
Ingår i: IEEE Journal of Quantum Electronics. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9197 .- 1558-1713. ; 43:1, s. 157-167
-
Tidskriftsartikel (refereegranskat)abstract
- The continuous-wave laser operation of Nd-doped tetragonal NaLa(WO4)(2) crystal is studied at room temperature by optical pumping in the spectral region overlapping AlGaAs diode laser emission. This crystal has inhomogenously broadened optical bands. From the room-temperature spectroscopic parameters determined it is found that the optimum Nd concentration for the F-4(3/2) -> I-4(J) laser channels must be in the 3-5 at.% range. For J = 11/2 and 13/2 channels (lambda approximate to 1.06 and 1.3 mu m) the most favourable polarization configuration is parallel to the crystallographic c axis, while for J = 9/2 little polarization dependence of the laser efficiency is predicted. Laser operation was achieved with a 3.35 at.% Nd-doped sample grown by the Czochralski method. The laser operation was tested in an hemispherical optical cavity pumped by a Ti:sapphire laser. Stimulated emission at lambda = 1056 nm was achieved for a wide spectral pumping range, lambda = 790-820 nm. Stimulated Raman scattering was achieved in the picosecond regime with an efficiency similar to that of monoclinic KY(WO4)(2) reference compound.
|
|