TY  - JOUR
A1  - Klein, Markus
A1  - Rama, Juliane
T1  - Time asymptotics of e(-ith(kappa)) for analytic matrices and analytic perturbation theory
JF  - Asymptotic analysis
N2  - In quantum mechanics the temporal decay of certain resonance states is associated with an effective time evolution e(-ith(kappa)), where h(.) is an analytic family of non-self-adjoint matrices. In general the corresponding resonance states do not decay exponentially in time. Using analytic perturbation theory, we derive asymptotic expansions for e(-ith(kappa)), simultaneously in the limits kappa -> 0 and t -> infinity, where the corrections with respect to pure exponential decay have uniform bounds in one complex variable kappa(2)t.
 In the Appendix we briefly review analytic perturbation theory, replacing the classical reference to the 1920 book of Knopp [Funktionentheorie II, Anwendungen und Weiterfuhrung der allgemeinen Theorie, Sammlung Goschen, Vereinigung wissenschaftlicher Verleger Walter de Gruyter, 1920] and its terminology by standard modern references. This might be of independent interest.
KW  - resonances
KW  - exponential decay
KW  - long-time corrections
KW  - Fermi golden rule
KW  - analytic perturbation theory
Y1  - 2014
U6  - https://doi.org/10.3233/ASY-141226
SN  - 0921-7134
SN  - 1875-8576
VL  - 89
IS  - 3-4
SP  - 189
EP  - 233
PB  - IOS Press
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Del Corpo, Alfredo
A1  - Vellante, Massimo
A1  - Zhelavskaya, Irina
A1  - Shprits, Yuri Y.
A1  - Heilig, Balazs
A1  - Reda, Jan
A1  - Pietropaolo, Ermanno
A1  - Lichtenberger, Janos
T1  - Study of the average ion mass of the dayside magnetospheric plasma
JF  - Journal of geophysical research : Space physics
N2  - The investigation of heavy ions dynamics and properties in the Earth's magnetosphere is still an important field of research as they play an important role in several space weather aspects. We present a statistical survey of the average ion mass in the dayside magnetosphere made comparing plasma mass density with electron number density measurements and focusing on both spatial and geomagnetic activity dependence. Field line resonance frequency observations across the European quasi-Meridional Magnetometer Array, are used to infer the equatorial plasma mass density in the range of magnetic L-shells 1.6-6.2. The electron number density is derived from local electric field measurements made on Van Allen Probes using the Neural-network-based Upper-hybrid Resonance Determination algorithm. The analysis is conducted separately for the plasmasphere and the plasmatrough during favorable periods for which both the plasma parameters are observed simultaneously. We found that throughout the plasmasphere the average ion mass is similar or equal to 1 amu for a wide range of geomagnetic activity conditions, suggesting that the plasma mainly consist of hydrogen ions, without regard to the level of geomagnetic activity. Conversely, the plasmatrough is characterized by a variable composition, highlighting a heavy ion mass loading that increases with increasing levels of geomagnetic disturbance. During the most disturbed conditions, the average radial structure shows a broad maximum around 3-4 Earth radii, probably correlated with the accumulation of oxygen ions near the plasmapause. Those ions are mostly observed in the post-dawn and pre-dusk longitudinal sectors.
KW  - magnetospheric average ion mass
KW  - magnetospheric plasma spatial
KW  - distribution
KW  - oxygen torus
KW  - geomagnetic activity dependence
KW  - field line
KW  - resonances
Y1  - 2022
U6  - https://doi.org/10.1029/2022JA030605
SN  - 2169-9380
VL  - 127
IS  - 10
PB  - American Geophysical Union
CY  - Washington, DC
ER  -