| 1. |
|
|
| 2. |
- Hoppe, Mathias, 1993, et al.
(författare)
-
Modeling synchrotron radiation images of runaway electrons
- 2017
-
Ingår i: 15th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- One of the most powerful means of studying runaway electrons in tokamaks is by measuring the synchrotron radiation they emit. In many current experiments, visible light and IR cameras are used to study the synchrotron radiation spot, and spectrometers measure the synchrotron radiation spectrum. Due to the strong dependence on the particle energy, pitch angle and radial position in both the synchrotron spot and spectrum, these can be used to extract valuable information about the runaway electron distribution function. Obtaining accurate information about the runaway electron distribution function from synchrotron radiation measurements however, requires both the magnetic field, camera location and camera spectral range to be handled properly and taken into account. In this contribution we present the synthetic synchrotron diagnostic SOFT (Synchrotron-detecting Orbit Following Toolkit) which simulates the synchrotron radiation from a population of runaway electrons whose energy, pitch angle and radial location are known in the outer midplane. By following the guiding-center orbits of the population, effects arising due to the inhomogeneity of the magnetic field are incorporated, which we show have significant effects on both the synchrotron radiation spot and spectrum.As an application of SOFT, we try to reproduce asynchrotron image from one discharge in the Alcator C-Mod tokamak. By taking measured parameters of the Alcator C-Mod discharge, a distribution function is obtained with the Fokker-Planck solver CODE, for which the emitted synchrotron radiation can then be simulated in SOFT, which shows good agreement. With SOFT, an interpretation for the synchrotron radiation spot observed in experiment can be given, and the characteristic comet shape of the Alcator C-Mod synchrotron radiation spot is shown to be the result of the vertical placement of the camera, together with the narrow set of pitch angles possessed by the particles, as well as their radial distribution.
|
|
| 3. |
- Huffman, JE, et al.
(författare)
-
Rare and low-frequency variants and their association with plasma levels of fibrinogen, FVII, FVIII, and vWF
- 2015
-
Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 126:11, s. E19-E29
-
Tidskriftsartikel (refereegranskat)abstract
- Twelve independent, novel, low-frequency (n = 2) and rare (n = 10) genetic variants were associated with fibrinogen, FVII, FVIII, or vWF. Nine were within previously associated genes, and 3 novel candidate genes (KCNT1, HID1, and KATNB1) were confined to cohorts of African ancestry.
|
|
| 4. |
- Tinguely, RA, et al.
(författare)
-
Synchrotron emission in Alcator C-Mod: spectra at three magnetic fields, visible camera images, and polarization data
- 2017
-
Ingår i: 59th Annual Meeting of the APS Division of Plasma Physics. ; , s. JP11.00096-
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Alcator C-Mod's high magnetic field allows runaway electron synchrotron emission to be observed in the visible wavelength range. Visible spectrometers were used to measure synchrotron spectra at three magnetic fields: 2.7, 5.4, and 7.8 T. Both a test-particle model and kinetic solver CODE (COllisional Distribution of Electrons) explore the energy evolution of the runaway population and the impact of magnetic-field-dependent synchrotron radiation as a power loss mechanism. Additionally, distortion-corrected visible camera images capture the spatial distribution and evolution of synchrotron emission in C-Mod. Initial results show good agreement between experiment and the new synthetic diagnostic SOFT (Synchrotron-detecting Orbit-Following Toolkit). Finally, a first look at synchrotron polarization data is presented.
|
|
