2,913 research outputs found
Recent progress in electron cyclotron radiative transport modelling of fusion plasmas in view of ITER and DEMO applications
Leptons from Dark Matter Annihilation in Milky Way Subhalos
Numerical simulations of dark matter collapse and structure formation show
that in addition to a large halo surrounding the baryonic component of our
galaxy, there also exists a significant number of subhalos that extend hundreds
of kiloparsecs beyond the edge of the observable Milky Way. We find that for
dark matter (DM) annihilation models, galactic subhalos can significantly
modify the spectrum of electrons and positrons as measured at our galactic
position. Using data from the recent Via Lactea II simulation we include the
subhalo contribution of electrons and positrons as boundary source terms for
simulations of high energy cosmic ray propagation with a modified version of
the publicly available GALPROP code. Focusing on the DM DM -> 4e annihilation
channel, we show that including subhalos leads to a better fit to both the
Fermi and PAMELA data. The best fit gives a dark matter particle mass of 1.2
TeV, for boost factors of 90 in the main halo and 1950-3800 in the subhalos
(depending on assumptions about the background), in contrast to the 0.85 TeV
mass that gives the best fit in the main halo-only scenario. These fits suggest
that at least a third of the observed electron cosmic rays from DM annihilation
could come from subhalos, opening up the possibility of a relaxation of recent
stringent constraints from inverse Compton gamma rays originating from the
high-energy leptons.Comment: 8 pages, 13 figures; added referenc
Cryopreservation of apices of in vitro plantlets of sugarcane (Saccharum sp. hybrids) using encapsulation/dehydration
Are focus and givenness prosodically marked in Kinyarwanda and Rwandan English?
This paper concentrates on whether systematic variations in pitch, intensity, and duration can be observed as a function of the focused or discourse-given status of a constituent in Kinyarwanda (Guthrie code JD.61), and a relatively recent variety of “New English” in contact with this Bantu language. Kinyarwanda is a tone language, in which the information-structural notion of focus has been reported to be expressed through changes in word order, with focus appearing clause-finally (Kimenyi 1988, Ndayiragije 1999, Ngoboka 2016). In contrast, Standard English is well-known for the prosodic boost associated with narrowly focused words and the prosodic reduction of post-focal items. Crosslinguistically, the prosodic expression of focus and givenness is progressively being considered a marked feature. Zerbian (2015a) predicts that it should not be found in a second language or a contact variety if it is not already present in the first language of a speaker or a group of speakers. Our study finds no evidence that information focus, exhaustive focus, or givenness systematically affect the prosody of Kinyarwanda. We also find no systematic effect of information structure in the variety of English spoken by our Rwandan participants, confirming that this is probably an area of English that is difficult to acquire
Electron-cyclotron absorption in high-temperature plasmas: quasi-exact analytical evaluation and comparative numerical analysis
Electron-temperature plasmas absorption in high-temperature plasmas: quasi-exact analytical evaluation and comparative numerical analysis
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