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[en] Electron spectra were obtained during two rocket flights into pulsating aurora from Southend, Saskatchewan. The first rocket launched at 1143:24 UT on February 15, 1980 flew into an aurora of background intensity 275 R of N2+ 4278 A and showing regular pulsations with about a 17 s period. Electron spectra of Maxwellian energy distributions were observed with an average E0 = 1.5 keV, rising to 1.8 keV during the pulsations. There was one-to-one correspondence between the electron energy modulation and the observed optical pulsations. The second rocket, launched at 1009:10 UT on February 23, flew into a diffuse auroral surface of intensity 800 R of N2+ 4278 A and with somewhat irregular pulsations. The electron spectra were again of Maxwellian energy distribution with an average E0 = 1.8 keV increasing to 2.1 keV during the pulsations. The results from these flights suggest that pulsating auroras occurring in the morning sector may be quite commonly excited by low energy electrons. The optical pulsations are due to periodic increases in the energy of the electrons with the source of modulation in the vicintiy of the geomagnetic equatorial plane. (auth)
[en] The Barium-GEOS rocket was launched from Esrange 20.20:10 UT on September 24, 1979 during the expansion phase of a magnetic substorm. Electron and positive ion measurements were performed with detectors looking in different directions relative the rocket spin axis with high angular resolution (2x20) in the energy range 70 eV - 21 KeV. Peaked electron energy spectra were observed during most of the flight. Highly collimated electron fluxes (within 10 degrees) were often seen at the energy level just below the peak energy. Most of the observed features of the electron distribution are found to be consistent with an acceleration mechanism including a parallel potential difference. The characteristic energy is found to increase and the number density to decrease as the accelerating voltage increases. This is in good agreement with a theory predicting that the potential drop is built up as a consequence of a magnetospheric dynamo requiring a current of a certain magnitude to flow along the magnetic field lines
[en] Observations of electrons precipitating from the Magnetosphere to the Ionosphere under a variety of auroral conditions suggest that the velocity distributions are formed by energy diffusion. Two possibilities are considered to account for the diffusion. It results either following electron acceleration through a potential difference, or as a consequence of plasma turbulence that accelerates electrons stochastically. It is found that the latter more readily accounts for the observations
[en] Results from the first two Substorm-GEOS rockets are presented. These rockets, as well as the third one, were launched from ESRANGE on January 27, 1979 into different substorm phases. The first rocket went into an active pre-breakup evening arc and the second one into a breakup close to magnetic midnight. Electron spectra of downcoming particles measured by a narrow energy bandwith detector show very narrow energy peaks as soon as the integral energy fluxes are high. These peaks always show populations of two different characteristic energies above the peak energy. One of the populations has properties similar to those found in the boundary layer plasma and the other one seems to be of plasma sheet origin. The plasma sheet like population is also seen where there are no signs of energy peaks, for example equatorward of the arc. The boundary layer plasma is exclusively connected with the signatures of acceleration
[en] The results of investigation of the temperature dependence of CdGa2Se4 absorption coefficient in the polarized radiation at 5–300 K and that of the emission intensity at 4.2–77 K are presented. The changes observed for the polarization dependence of absorption coefficient and the radiation intensity with decreasing temperature are attributed to a different velocity of motion of states of the valence-band top Γ3 + Γ4 and Γ2 with changing tetragonal compression.
[en] The energy spread primary electron beams produced by the electron guns used in full current spectroscopy (FCS) exceeds 1 eV. Therefore no peculiarities having energy width more than 0.1-0.9 eV can be determined in FC-spectra. In this paper the method that allows to extract the real form of FC with energy resolution 0.1 eV is described. (author)
[en] In November 2017, the DAMPE collaboration announced their first measurement of the electron spectrum between energies of 25 GeV and 4.6 TeV, including a narrow peak at ∼1.4 TeV with marginal significance. However, this feature is not observed in the larger statistic H.E.S.S. spectrum reported a few month earlier in the ICRC 2017. In this work, we perform a likelihood ratio method to test whether the DAMPE excess is compatible with the preliminary H.E.S.S. spectrum. By assuming the performance of the H.E.S.S. analysis is smooth with the electron energy, a CL upper limit on a stable DAMPE-like signal is set at of the DAMPE excess flux. The further investigation will rely on the formal publication of H.E.S.S. spectrum and higher statistic spectrum of DAMPE in the future.