The alpha-relaxation time τ is deﬁned as the time where the normalized coherent intermediate-scattering function decays to a value of 1/e, evaluated at the closest discrete wave number to q = 18 nm−1 , the approximate location of the ﬁrst peak in the static structure factor.
Fractional Stokes-Einstein and Debye-Stokes-Einstein relations in a network forming liquid
Marsch et al. (1982) interpreted vαp > 0 as a consequence of the wave acceleration that favors alpha particles, and vαp < 0 as a signature of the solar wind being driven primarily by the electrostatic ﬁeld since alpha particles experience only half the electric force that protons do.
Angular momentum transport and proton-alpha differential streaming in the solar wind
Third, the compressional waves accompanying large amplitude Alfv´en waves may help convert the free energy that derives from the differential streaming into alpha heating, thereby reducing vαp (Kaghashvili et al. 2003).
Angular momentum transport and proton-alpha differential streaming in the solar wind
Previous computations involving ion cyclotron waves indicate that, in the case of neutral heating, the alpha particles tend to ﬂow slower than protons (see the dispersionless case in Fig.1 of Hu & Habbal 1999).
Angular momentum transport and proton-alpha differential streaming in the solar wind
Then at t = 0 the wave-function ψ(r, t) of the alpha-particle will be concentrated within a spherical potential wall around the point r = 0 where the nucleus is found.
A Simple Solution of the Arrival Time Problem
How to deduce from it the time distribution of the clicks of the alpha-detector? In order to concentrate on the time behaviour alone without complexities of the angular distribution we assume isotropic initial conditions which lead to spherically symmetric wave-function ψ(r, t).
A Simple Solution of the Arrival Time Problem
We can describe a uranium nucleus by a wave-function including an outgoing alpha-particle wave which determines the probability that the nucleus will decay tomorrow.
A Quantum Past
For example, the wave functions with bin=1.45 fm would give a good description for the alpha-particle core of 6He, but they are spatially much too compressed to describe the halo neutrons of 6He.
Realistic effective interactions for halo nuclei
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