Search

In the d-electron system YFe2Ge2, an unusually high and temperature dependent Sommerfeld ratio of the specific heat capacity C /T ∼ 100 mJ/(mol K2) and an anomalous power law temperature dependence of the electrical resistivity signal Fermi liquid breakdown, probably connected to a close-by quantum critical point. Full resistive transitions and DC diamagnetic screening fractions of up to 80% suggest that pure samples of YFe2Ge2 superconduct below 1.8 K. (© 2014 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim)

On 8/27/96 from 8 to 10:36 UT the POLAR satellite crossed the dayside cusp and observed very energetic ionospheric O ≤ +2 ions which had a magnetic moment spectrum, M(E) that followed a power law. Later at 14:45 to 15:30 UT the satellite passed through the ring current at 15–16 MLT where the O ≤ +2 ions again had a M(E) power law form but with a spectral amplitude that was two orders of magnitude lower. During this period from 8 to 16 UT there were no magnetic storms as Dst had an average value of ∼ −5 nT. The comparison of the fluxes at constant M means that the energetic ions in the cusp cannot have a source in the ring current. Arguments are given that the comparison of these sequential measurements of M(E) are valid and that a new mechanism is needed for producing these energetic ionospheric ions observed in the cusp.

A possible cusp acceleration mechanism has been investigated during a major geomagnetic storm on May 4, 1998 when the magnetosphere was compressed and eroded. At 5:00–12:05 UT, the WIND spacecraft was about 213 R E upstream from the Earth, the GEOTAIL was in the post dusk magnetosheath, and the POLAR traveled in its outbound orbit from the equatorial radiation belt to the high-altitude dayside cusp and crossed the magnetopause into the magnetosheath. Many instances of in situ ion energization (to >MeV) were observed by POLAR during this period. Simultaneous observations indicated that no comparable flux was observed by WIND. Ion fluxes measured by POLAR were higher than that measured by GEOTAIL, indicating ion source regions near or within the magnetosphere. The measured ions show some interesting features: (1) In the radiation belt, in the magnetopause boundary layer, and in the dayside cusp, most 1– 200 keV / e fluxes were around pitch angles of 90°; while in the magnetosheath, the fluxes came from a broad hemispherical direction between ∼sunward and earthward. (2) At around 6:00 UT, the MeV ion flux was lower in the magnetosheath than in the adjacent magnetosphere. (3) There were two CEP (cusp energetic particle) events with 2–3 orders of magnitudes enhancements of MeV ion fluxes. (4) The MeV ions in one CEP event had a peak flux higher than that of the intense outer radiation belt in the equatorial plane. (5) The 100 keV / e O ions which originated from the ionosphere were observed in both the outer cusp and the magnetopause boundary layer. (6) There were no large magnetic field fluctuations upstream before the bow shock. These observations suggest a likely source of substantial particle energization exists in the cusp region.

A new acceleration and possible trapping region of the magnetosphere has been discovered by the POLAR spacecraft through the observations of the cusp energetic particle (CEP) events. The events were detected in the dayside high-altitude cusp and were associated with a dramatic decrease and large fluctuations in the local magnetic field strength. These events could last for hours, in which the measured helium ions had energies up to 8 MeV (Chen, 1997a, 1998). A fundamental question to be addressed is the origins of the cusp energetic ions. Simultaneous observations indicated that the ion fluxes in the CEP events were higher than that in both upstream and downstream from the bow shock. We have determined the power spectra of the local magnetic field turbulence calculated over the September 18, 1996 CEP event periods for fluctuations in the ultra-low frequency (ULF) ranges, corresponding to periods of about 0.33–500 seconds. It is found that the mirror parameter, defined as the ratio of the square root of the integration of the parallel turbulent spectral component over the ULF ranges to the local mean field, is correlated with the intensity of the MeV helium flux. A statistical study of the CEP events indicated that the MeV helium flux was also proportional to the difference between the maximum and the minimum magnetic field in the event. These results represent a discovery that the high-altitude dayside cusp is a new acceleration and possible trapping region of the magnetosphere.

New observations from the NASA GGS POLAR satellite of cusp energetic particle [CEP] events indicate that the mechanism(s) in the dayside cusp accelerate the solar wind plasma to 100s and 1000s of kiloelec-tronvolts energies. The mechanism seems to be active much of the time but is impulsive in nature with an event having a lifetime of 45–60 minutes. This mechanism is capable of producing an energetic particle layer that straddles the magnetopause along the flanks of the magnetosphere. These energetic particles can enter the magnetosphere as a result of gradients in the magnetic field and the resultant drifts they cause; ions entering along the dawn flank drifting to the west and electrons entering along the dusk flank drifting east will carry a current. Since these particles will drift to distances less than six earth radii in the nightside equatorial plane, their variations in time probably control the dynamics of the magnetosphere in the range 6

A major geomagnetic storm occurred at 5:00-12:05 UT on May 4, 1998. During this period, the magnetosphere was compressed and eroded; POLAR traveled in its outbound orbit from the equatorial radiation belt to the cusp and crossed the magnetopause into the magnetosheath. Two CEP-like (Cusp Energetic Particle) events with two to three orders of magnitudes enhancements of MeV ion fluxes were measured. The first event had a peak flux higher than that of the intense outer radiation belt in the equatorial plane. The shape of the measured energy spectra (in the unit of keV/e) were ion species dependent. For He+/He++ ratio at 18-269 keV/e, the difference between the radiation belt and the magnetosheath can be by a factor of as large as 62. In the magnetosheath, the 18-269 keV/e ion composition are variable, indicating a mass dependent acceleration process. These MeV ions may be energized by a mechanism in the cusp responsible for the CEP events previously reported.

Observations made by the Polar satellite have shown that plasma of solar wind/magnetosheath origin is rammed into the high altitude polar cusp creating a diamagnetic cavity of large dimensions. The Earth’s dipole field can be excluded from this region in a turbulent manner with the magnitude of the field strength reaching close to zero nT at times. At such times energetic particles are produced in this region in intensities which exceed those measured in the trapping regions of the magnetosphere beyond L =6.5. These particles can then flow back out of the cusp along field lines that form the magnetopause. A fraction of these particles can enter the magnetosphere along the magnetopause on the dusk and dawn flanks. Due to existing gradients in the geomagnetic field, cusp accelerated ions can enter the magnetosphere along the dawn flank and electrons along the dusk flank. For those particles entering near the geomagnetic equatorial plane with pitch angles close to ninety degrees, they will drift along contours of constant magnetic field strength reaching deep into the nightside inner magnetosphere. From observations made by the Polar, ATS-6, and ISEE satellites it is argued that this cusp source appears to be capable of providing energetic ions to the magnetosphere and possibly energetic electrons which form the source population of the subsequent radial diffusion and formation of the radiation belts.

In 1996, the POLAR spacecraft discovered a new phenomenon called a cusp energetic particle (CEP) event, in which the He ions had energies up to 8 MeV. A total of 75 CEP events have been reported (Chen et al., 1998). The CEP events showed six unusual features: (1) They were detected in the high altitude dayside cusp; (2) large fluxes of energetic (> 20 keV) ions were observed for periods of hours where such “trapped” ions should not be stably trapped; (3) the associated magnetic field was turbulent and greatly depressed appearing to reach a null value in many cases; (4) the 1–200 keV/e helium ions are He++; (5) compared to O>+2, the O

The Charge and Mass Magnetospheric Ion Coimposition Experiment (CAMMICE) on the board the POLAR spacecraft observed more than 70 cusp energetic particle (CEP) eventin 1996. All of these events were associated with a decrease in the magnitude of the local magnetic field measured by the Magnetic Field Experiment (MFE) on POLAR. This is an important discovery, which reveals six interesting features for the CEP events: (1) They all were detected in the dayside at high latitude near apogee; (2) their energies were in excess of 2.4 MeV; (3) an individual CEP event could last for hours; (4) the event-averaged intensity of 1–200 keV/e helium was anticorrelated with the magnitude of the local geomagnetic field but correlated with the turbulent magnetic energy density; (5) the events were associated with an enhancement of the low frequency electromagnetic noise; and (6) a possible seasonal variation was found for the occurence of the events with a maximum in September. The measured high charges state of helium and oxygen ions in the CEP events indicates a solar source for these particles. A possible explanation is that the energetic helium ions are energized from lower energy helium by a local acceleration mechanism associated within the high-altitude dayside cusp. These observations represent a discovery of a major acceleration region of the magnetosphere.

A study of geomagnetically confined helium ions in the range 0.52–8.2 MeV ion kinetic energy was made with the CAMMICE Heavy Ion Telescope (HIT) during April–October 1996. Much of the year 1996 was remarkably geomagnetically quiescent with absence of major magnetic storms, large shock transits through the magnetosphere, or penetration injection events. Indeed, between two minor magnetic “storms” on January 13 (DST minimum ∼ −88 nT) and October 23 ( D ST minimum ∼ −110 nT) 1996 there was a long geomagnetically relatively undisturbed time period with D ST excursions in the few tens of nT at most. Using the POLAR ephemeris data, it was found that the nominal L -parameter location of the radial peaks in helium ion fluxes varied considerably with azimuthal location around the Earth, i.e., with magnetic local time (MLT), to be observed at L =2.7−2.6 respectively in the dawn sector (near MLT∼5 hr) and typically a nominal L -parameter farther out in the dusk sector (near MLT∼17 hr). The empirical helium ion anisotropy could be reasonably approximated by an unambiguous sin n α 0 dependence (where α 0 is equatorial pitch angle) only fairly close to the geomagnetic equator, at equatorial pitch angles α 0 > 45°. For smaller equatorial pitch angles, the distribution was often seen to be flatter than describable by this relation alone. There may be several interacting causes of these observed features, including (1) effects of differences between the real geomagnetic field and the model field (IGRF 95) used in the POLAR ephemeris, (2) consequences of coupling between ion transport dynamics, spectra and exospheric interactions, and (3) possibly also real physical effects of the azimuthally asymmetric geoelectric field in conjunction with large gradients in the helium ion distribution function. Further work is needed to delineate the relative importance of these influences on the structure of radiation belt helium ions.

We present Polar plasma wave data during cusp energetic particle (CEP) events at 6-9 R(sub E). These data suggest the presence of coherent electrostatic structures that are highly localized and that have typical velocities on the order of hundreds to thousands of kilometers per second along the ambient magnetic field. Some of the wave signatures are solitary waves and some are wave packets. The Polar wave instrument also provides evidence that some of the bursts of electromagnetic waves (with frequencies of a few hundred Hz and just below the electron cyclotron frequency around 800 Hz to 1-2 kHz) that are observed are coher&nt and propagating both up and down the field lines. Electron cyclotron harmonic (ECH) waves are often detected but their duration is usually short (less than 1 second). Low Frequency (less than 1 kHz), broadband, bursty electromagnetic waves are also present. The Polar wave data results are used to obtain a better understanding of the macro/microphysics during a CEP event that takes place on September 11, 1996, by correlating various Polar (approximately 7.0 R(sub E)) and Akebono (approximately 1.4 R(sub E)) data while both spacecraft are in or near the cusp/cleft region and nearly on the same field line, and magnetometer data from the Canadian Intermagnet and Canopus ground stations, which lie near the base of the magnetic footprint passing through Polar. Solar wind and magnetic field data from the interplanetary medium and magnetosheath are provided by the Geotail and IMP-8 satellites, respectively. Some of the cusp waves may be indicators of the reconnection process taking place through the cusp, the result of mixing of magnetosheath with magnetospheric plasma, and the consequence of an anisotropic electron population in a depressed magnetic field. The low frequency electromagnetic waves are still under study to determine their role, if any, in the heating and acceleration of the MeV He ions during CEP events.

A new magnetospheric phenomenon called a cusp energetic particle (CEP) event was observed by the POLAR spacecraft. CEP events were detected in the dayside polar cusp near the apogee of POLAR and could last for hours, in which the measured helium ions had energies up to 8 MeV [Chen et al., 1997a, 1998]. A fundamental question is where do the cusp MeV ions come from? To answer this question, we have compared the ion flux in the CEP events with that in both the upstream and the downstream from the bow shock and found that bow shock acceleration cannot explain the measured ion flux in the CEP events. We have further determined the power spectra of the local magnetic field turbulence calculated over the September 18, 1996 CEP event periods for fluctuations in the ultra-low frequency (ULF) ranges, corresponding to periods of about 0.33–500 seconds. It is found that the integrated power of the turbulent spectra over the ULF ranges is correlated with the intensity of the MeV helium flux. These new results provides the first direct observation evidence that the high-altitude dayside cusp is a new acceleration region of the magnetosphere.

We report on the POLAR/ CEPPAD discovery of a trapped, 60°

The Charge and Mass Magnetospheric Ion Composition Experiment (CAMMICE) on board the Polar spacecraft observed 75 energetic particle events in 1996 while the satellite was at apogee. All of these events were associated with a decrease in the magnitude of the local magnetic field measured by the Magnetic Field Experiment (MFE) on Polar. These new events showed several unusual features: (1) They were detected in the dayside polar cusp near the apogee of Polar with about 79% of the total events in the afternoonside and 21% in the morningside; (2) an individual event could last for hours; (3) the measured helium ion had energies up to and many times in excess of 2.4 MeV; (4) the intensity of 1-200 KeV/e helium was anticorrelated with the magnitude of the local geomagnetic field but correlated with the turbulent magnetic energy density; (5) the events were associated with an enhancement of the low-frequency magnetic noise, the spectrum of which typically extends from a few hertz to a few hundreds of hertz as measured by the Plasma Wave Instrument (PWI) on Polar; and (6) a seasonal variation was found for the occurrence rate of the events with a maximum in September. These characterized a new phenomenon which we are calling cusp energetic particle (CEP) events. The observed high charge state of helium and oxygen ions in the CEP events indicates a solar source for these particles. Furthermore, the measured 0.52-1.15 MeV helium flux was proportional to the difference between the maximum and the minimum magnetic field in the event. A possible explanation is that the energetic helium ions are energized from lower energy helium by a local acceleration mechanism associated with the high-altitude dayside cusp. These observations represent a potential discovery of a major acceleration region of the magnetosphere.

On August 27, 1996, a two-hour energetic heavy ion event (∼ 1 MeV) was detected at 8:25 UT at apogee (∼ 9 R e and an invariant latitude of ∼ 80°), by the Charge and Mass Magnetospheric Ion Composition Experiment onboard POLAR. The event, with a maximum spin averaged peak flux of ∼ 150 particles/(cm 2 -sr-s-MeV), showed three local peaks corresponding to three localized regions; the ion pitch angle distributions in the three regions were different from an isotropic distribution and different from each other. No comparable flux was observed by the WIND spacecraft. The appearance of lower energy He ++ and O >+2 during the event period indicates a solar source for these particles. From region 1 to 2 to 3, the helium energy spectra softened. A distorted magnetic field with three local minima corresponding to the three He peak fluxes was also observed by POLAR. A possible explanation is that the energetic He ions were energized from lower energy helium by a local acceleration mechanism that preferred smaller rigidity ions in the high altitude polar cusp region.

The recent discovery of energetic particles trapped in the cusp (CEP) in close association with diamagnetic cavities (CDC) strongly suggest a new location for particle acceleration. Such an acceleration region has long been sought as the mysterious source of outer radiation belt electrons (ORBE) and ring current ions (RCI). In this paper we present some theoretical support for the acceleration mechanism and estimate that the quadrupole cusp may be the most powerful accelerator in geospace. If so, then the CEP/CDC may provide a useful predictor of the injection of ORBE/RCI fluxes that are detrimental to geosynchronous spacecraft.

The survey and evaluation of existing public parking facilities were carried out, which had important practical significance to resolve conflicts over demand and supply of parking facilities. Taking Huizhou downtown as a study area, we surveyed parking facilities mainly by daily observing and recording. Parking facilities supply, characteristics, and demand were analysed by calculating parking utilization and turnover rate. Based on GIS, the distance-based and time-based accessibility of parking facilities were analysed to evaluate spatial distribution. The results indicated that a large spatial difference in supply and characteristics of parking was shown in public parking facilities of Huizhou downtown and that the parking demand was large. Furthermore, there existed imbalance in spatial distribution of parking facilities in Huizhou downtown area. Our study suggested that it was imbalanced and irrational between parking facilities supply and parking demand, that the planning of parking facilities was inadequate and that management system was incomplete.

The paper calculates yearly averaged power spectra of interplanetary magnetic field turbulence at 1 AU over the period 1965-1988 for fluctuations in the frequency range 5.8 x 10 exp -6 to 4.6 x 10 exp -5 Hz, corresponding to periods of 6-48 hr. The amplitudes of the spectra vary with the sunspot cycle and are inversely correlated with the intensity of about 10-GeV cosmic rays. The observed spectra are used to calculate a lower limit to the cosmic ray scattering mean free path employing resonant magnetostatic quasi-linear theory for both 'slab' and isotropic geometries of the turbulence. The mean free paths thus obtained are typically about 0.1 AU in the slab model and about 0.3 AU in the isotropic model, but they are not significantly correlated with the modulated galactic cosmic ray intensity recorded by neutron monitors. It is inferred that the scattering processes described by resonant magnetostatic theory play, at best, a very minor role in the solar modulation of about 10-GeV cosmic rays.

[1] We examine 6 years of cusp crossings by the Polar spacecraft to determine the size and solar wind dependence of cusp diamagnetic cavities (CDCs) and energetic particle events (CEPs). Both are frequently observed (about 50% of the time spent in the cusp). Neither shows a strong statistical dependence on upstream conditions beyond variations in the cusp itself. CEPs are found throughout the cusp, peaking near the magnetopause. CDCs are primarily found near local noon and close to the magnetopause, forming an extended region against the magnetopause.

became observable in the energy window of Polar were transported from the high-latitude magnetopause to the inner magnetosphere when the convection electric field was strong. When the convection electric field was weak, the ions were reflected toward the distant tail. The O 6+ ions that became observable in the energy window of Geotail were sufficiently transported from the low-latitude magnetopause to the near-Earth magnetotail regardless of the strength of the convection electric field. The observational facts may be adequately explained in terms of ion transport paths depending on the convection electric field with different entry points.

Directing towards the characteristics and importance of copper strips surface inspection, this paper proposes a copper strips surface inspection system based on artificial intelligence from the standpoint of artificial intelligence. It uses computer vision to capture defects images, uses Hu invariant moments as the eigenvectors and uses BP neural network based on genetic algorithm combined with expert system to train and learn the samples. The trained weights are used to diagnose as the knowledge base and a copper surface defects inspection system based on intelligent fusion is constructed . The experimental results proved that intelligent fusion model can compliment all kinds of intelligent models and has a better performance than single model on copper strips surface inspection.

[1] We examine Polar data for several high-altitude cusp crossings to characterize “Cusp Diamagnetic Cavities” (CDCs). In particular, we determine the relationship between the magnetic field and thermal pressure of the local plasma. The cusp is characterized by high density and the presence of stagnant solar wind plasma throughout. The CDCs represent a distinct region within the cusp, possessing a depressed and turbulent magnetic field in addition to the other cusp properties. We find the CDCs are colocated with “Cusp Energetic Particle” (CEP) events. In CDCs, depressions in the field are strongly correlated to local enhancements in plasma density and thus pressure, supporting the “diamagnetic” label. No correlation between field and plasma is found in the cusp outside of the CDC. The colocation of CDCs and CEP events suggests constraints on the origin of CEPs.

In this paper, novel video transmission architecture is proposed to meet the error robust requirement of wireless video communications. This architecture uses user-defined protocol to provide efficient bandwidth access from wireless link. By taking the time-varying wireless channel condition and video codec characteristics into account, first, we present an end-to-end transport architecture for video streaming over wireless network. Second, we adopt channel of Bernoulli channel model from application layers of 3G networks. And we propose a dynamically estimate the time-varying wireless network condition through estimate of throughout, RTT and merit of packet delay time. Third, we use H.264 as an experiment platform. A data partition scheme is also used to enhance error resilience performance. This architecture is also suitable for various motion compensation based standards like H.261, H.263 series, MPEG-1, MPEG-2, MPEG-4. The simulation results show our strategies can significantly improve the robustness of wireless video transmission.

Recently, it becomes more important to ensure the quality of the products as copper strip manufacturing has been highly developed. The most difficult problem in process control and automatic inspection is classification of surface defects, so we develop an improved RBF (radial basis function) neural network classifier based on SVM (support vector machine) to automatically learn complicated defect patterns and use pseudo Zernike moment invariant as the defect feature. The optimal initial parameters of RBF network are gained through SVM, which has resolved the problems in traditional methods, e.g. long learning time, and easily getting into local minimum, etc. Furthermore, a BP learning algorithm is presented to adjust these hidden node parameters as well as the weights of the SVM-RBF. The experimental results show that the method is effective.

Some new thiosemicarbazones have been synthesized by condensation reaction of substituted 1-phenacyl-1,2,4-triazoles and-benzotriazoles with thiosemicarbazide, which underwent cyclization with acetic anhydride to give a series of substituted thiadiazoline derivatives in good yields. Their structures were confirmed by elemental analysis, IR, 1H NMR, and MS.

[1] Observations on October 30, 1978 show the ISEE 1 spacecraft passing though the high-altitude dayside northern cusp region from roughly 16:00 to 18:30 UT, during a slow solar wind period (∼380 km/s). More than two orders of magnitude enhancements of the cusp energetic particle (CEP) fluxes are observed along with a depressed and turbulent local magnetic field and both ionospheric and solar wind plasma. The clock angle of the local magnetic field is different from that of the IMF, implying that the spacecraft was indeed inside the magnetosphere. The observed variations of the pitch angle distributions provide a unique opportunity to determine the structure of the cusp. The CEP fluxes were measured at about 8.5 hours MLT when the IMF had both an 8–10 nT duskward and southward component. The dawnside location of the cusp under these IMF conditions is unexpected by the existing models. No obvious time-energy dispersion is measured for the CEP fluxes. The time evolution of the phase space density as the spacecraft crossed the cusp boundary layer exhibits a positive gradient pointed to the high-altitude cusp, indicating a probable cusp source of the energetic particles. Through a careful analysis of the data available, we report the first detailed study of the equatorial orbiting ISEE 1 spacecraft passing through the high altitude cusp region.

The cusp energetic particles (CEP) have been observed in the dayside high-altitude cusp region, showing orders of the magnitude increase of ion intensities with energies from 20 keV up to 10 MeV. Associated with these charged particles are large diamagnetic cavities with significant fluctuations of the local magnetic field strength. The CEPs may provide a answer to a long-standing unsolved fundamental issue about the origin of upstream energetic ions. On June 28, 1999, the WIND spacecraft (near the forward libration point) observed a sudden increase (by more than one order of magnitude) of the solar wind pressure at about 4:45 UT and an upstream ion event at 5:23–5:45 UT, the INTERBALL-1 spacecraft located just upstream of the bow shock in the morningside measured an upstream ion event from 5:16 UT to 6:00 UT, the GEOTAIL spacecraft in the afternoonside near the bow shock detected an upstream ion event from 5:50 UT to 6:16 UT, while the POLAR satellite at 7 hours of magnetic local time detected an energetic particle event in the high-altitude region associated with turbulent diamagnetic cavities from 5:12 UT to 6:30 UT. Energetic oxygen ions of both ionospheric and solar wind origin were observed by the POLAR spacecraft during this event period. The energetic ions and the associated turbulent magnetic field are very similar to what was found in the high-altitude dayside cusp region. It is argued that the bow shock is not the main source of energetic ions in these upsteam events since their energy spectra are independent of the solar wind velocity and their intensities are independent of the bow shock geometry and solar wind pressure. The event onset was first detected in the cusp by POLAR at 5:12 UT, then near the bow shock in the morningside by INTERBALL-1, and then in far the upstream by WIND. The measured energetic ion intensity decreased with increasing distance from the cusp before 5:42 UT. At 5:50 UT, GEOTAIL detected the event onset that showed an energy dispersion, suggesting a drift effect. These observational facts together with the IMF directions suggest that these upstream energetic ions most likely came from the cusp.

Recently, large diamagnetic cavities with a size of as large as 6 Re have been observed in the dayside high-altitude cusp regions. Associated with these cavities are charged particles with energies from 20 keV up to 10 MeV. Their seed population is a mixture of ionospheric and solar wind particles. The energetic ion intensity, charge composition, energy spectrum, and phase space density observed in the high-altitude dayside cusp have been compared with that measured in the outer radiation belt over an energy range of 1-200 keV/e for protons and He ++ ions and of 41-200 keV/e for O + ions. It is found that (1) the shape of ion energy spectra in the cusp is different from that in the outer radiation belt, (2) the ion phase space densities in the outer radiation belt are organized by magnetic moment, and (3) the ion phase space density of both He ++ and O + in the cusp are higher than that in the outer radiation belt at a given magnetic moment. These results suggest that (1) the measured cusp energetic ions cannot be explained by simple transport from an outer radiation belt (or ring current) source; rather, (2) a nonadiabatic energization process would be required to relate the cusp energetic ion population to the belt ion population, and (3) cusp energetic particles are potentially an additional independent source of the charged particles in the outer radiation belt.

[1] On 28 June 1999 the Wind spacecraft (near the forward libration point) observed a large solar wind pressure spike from 0445 UT to 0600 UT. The Polar satellite at 7 hours magnetic local time detected an energetic particle event in the high-altitude region associated with turbulent diamagnetic cavities from 0512 UT to 0627 UT. The particles and cavities are very similar to those that were previously found in the high-altitude dayside cusp region. They are independent of both the solar wind velocity and the interplanetary magnetic field (IMF) vectors. The enhancements of the magnetic field fluctuations in the ultra-low frequency range measured by the Wind were also observed by the Polar. Most of the time, during the event period, the IMF had a duskward component, suggesting that cusp diamagnetic cavities also existed in the postnoon sector in the Northern Hemisphere. Energetic ions of both ionospheric origin and solar wind origin were observed by the Polar spacecraft during this event period. The He++/H+ ratio in the diamagnetic cavities was a factor of four higher than in the quasi-trapping region before the event onset, while the He+/He++ ratio in the cavities was more than one order of the magnitude lower. In this event, the measured cusp ions had energies up to 4 MeV. No clear relationship between the cusp energetic ion flux and the IMF cone angle was found. The Interball 1 spacecraft located just upstream of the bow shock in the prenoon sector measured an upstream ion event from about 0516 UT to 0600 UT. The onset of the energetic ions observed by Interball 1 in the upstream event was the same for different energies; the ion energy spectra were independent of the solar wind velocity and their intensities were independent of the bow shock geometry and the solar wind density. The energetic ion event onset was first detected in the cusp by Polar at 0512 UT, then near the bow shock in the prenoon by Interball 1 at 0516 UT, and then in the far upstream by Wind at 0523 UT. The measured energetic ion intensity decreased with increasing distance from the cusp diamagnetic cavities. These observational facts together with the IMF directions suggest that (1) this large solar wind pressure event produced an extremely large diamagnetic cavity (>10 RE) within the magnetosphere, (2) the bow shock was not the main source of both the cusp and upstream energetic ions, and (3) the upstream energetic ions most likely came from the cusp.

The high-altitude dayside cusp is an extremely dynamic region in geospace. Compared to the equatorial magnetosheath, orders of magnitudes enhancements of energetic ions (from 40 keV to MeV) of both the solar wind and the ionospheric origins have been observed in the high-altitude dayside cusp. These measured cusp energetic ions were associated with a dramatic decrease and large fluctuations in the local magnetic field strength. One important question is where are these ions going? Previous studies suggested that the cusp plasma may enter into the magnetopause boundary layer and that no obvious ion heating was observed inside the high-latitude boundary layer (HLBL). During high solar wind pressure periods when the magnetosphere was compressed, the POLAR spacecraft might travel through the magnetopause boundary layer and the sheath-like region. Recent POLAR observations indicated that the energetic ions in the dayside magnetopause/magnetosheath boundary layers were a mixture of ions of solar wind and ionospheric origins, similar as in the cusp. Further comparisons of the ion energy spectra, the ion charge state composition, and the ion anisotropies suggest a likely source for the HLBL energetic ions exists in the cusp region.

[1] The paper by Trattner et al. [2001, hereinafter referred to as TETAL] reanalyzes the data of Chen et al. [1998, hereinafter referred to as CFS] and attempts to prove two statements: first, that the energetic ions observed in the cusp by CFS were actually accelerated at the bow shock and then transported to the cusp, and second, that the detected ions are not accelerated locally. Quoting TETAL's abstract, “An alternative explanation for the energetic particle events is that they are accelerated at the quasi-parallel bowshock, then transported downstream and enter the cusp along newly reconnected field lines or some other solar wind entry mechanism… No local acceleration is required to explain the observed CEP events up to 150 keV/e.” We object that neither assertion of TETAL is defensible on theoretical or experimental grounds. Indeed we find the conclusions of the paper are flawed by both statistical and logical errors. In section 1 we outline the logical flaws, in section 2 we outline the misuse of the scientific method, in section 3 we outline the improper use of statistics, and in section 4 we outline the mishandling of spacecraft data. Finally, in section 5 we apply the scientific method of hypothesis testing to the two theories, arguing that given complete ignorance of the data, the hypotheses of CFS are preferable to TETAL.

[1] Extremely large diamagnetic cavities with a size of as large as 6 RE have been observed in the dayside high-altitude cusp regions. These diamagnetic cavities were associated with strong magnetic field turbulence. Associated with these cavities are >40 keV ions that are more typical of the trapped ring current and radiation belt populations than the solar wind. The charge state distribution of these cusp cavity ions was indicative of their seed populations being a mixture of ionospheric and solar wind particles. In April 1999, the cusp diamagnetic cavities were observed by the Polar spacecraft almost in every orbit, indicating that such cavities are always there day by day. Some of the diamagnetic cavities were independent of the interplanetary magnetic field directions, suggesting that the cusp diamagnetic cavities are different from the magnetospheric sash predicted by MHD simulations. During a high solar wind pressure period on 21 April 1999, the Polar spacecraft observed lower energetic (>20 keV/e) ion fluxes in the dayside high-latitude magnetosheath than that in the neighboring cusp cavities. By their geometry cusp magnetic field lines are connected to all of the magnetopause boundary layers. These energetic particles in the cusp diamagnetic cavity together with the cusp's connectivity probably have significant global impacts on the geospace environment.

[1] From a study of the 4 May 1998 storm event, Chang et al. [2001] (hereinafter referred to as CETAL01) suggested that ‘‘ions are accelerated at the quasi-parallel bow shock to energies as high as 1 MeVand subsequently transported into the magnetosheath during this event’’ and mentioned that ‘‘This is confirmed by a comparison of energetic ion fluxes simultaneously measured in the magnetosheath and at the quasi-parallel bow shock when both regions are likely connected by the magnetic field lines’’ (see their Abstract). After an inspection of the measured energetic ion data, however, one finds that CETAL01 have misplotted the observed ion energy spectrum in the ‘‘magnetosheath’’ (near the cusp) to lower energy which brings it in closer agreement to the flux measured near the quasi-parallel bow shock, making their analysis suspect. In fact, simultaneous measurements at this time indicate that (1) the energetic ion flux near the cusp was about one order of magnitude higher than that near the quasi-parallel bow shock, (2) the energetic ion time signatures were seen first near the cusp then near the bow shock, and (3) the energetic ion flux observed near the bow shock was independent of bow shock geometry. Each of these three facts is sufficient to demonstrate that the quasi-parallel bow shock was not the main source of the energetic ions near the cusp during this event. [2] CETAL01 stated that ‘‘A comparison of Interball and Polar ion spectra can potentially falsify our bow shock source hypothesis and is now the focus of our analysis.’’ In Figure 11 of CETAL01, accordingly, they compared the energetic ion flux measured by Interball near the quasiparallel bow shock with that measured by Polar near the cusp during the interval 1101–1142 UT on 4 May 1998, where their Polar/CEPPAD energetic ion data (open circles in their Figure 11) were taken only from the ion sensor that was looking 90 from the Polar spin axis. Our Figure 1 replots the Interball data (stars) and the Polar/CEPPAD data (open squares) for the same time interval. Comparing Figure 11 of CETAL01 to our Figure 1, we find that they have misplotted the CEPPAD ion energy spectrum near the cusp to the lower energies which reduces the difference between Interball and Polar ion fluxes. A closer inspection of their Figure 11 suggests that for each energy interval (channel) near the cusp they used the lower energy threshold to represent it without taking into account the effective energy passband [McKinnon and Fritz, 1976] of the steep energy spectrum, and the resulting energy spectrum near the cusp shown in their Figure 11 is thus lower than the actually observed spectrum as shown in our Figure 1. [3] This is not the only case where CETAL01 misplotted the observed ion energy spectrum around the cusp to lower than the actually observed spectrum, for in an earlier paper, Chang et al. [1998] (hereinafter referred to as CETAL98) misplotted the MICS (Magnetospheric Ion Composition Sensor) lower energy limit from 1 keV/e to 0.6 keV/e which brought the cusp fluxes into better alignment with ‘‘bow shock ion spectra,’’ and in addition, misplotted the HIT (Heavy Ion Telescope) helium data point in the cusp below the actual observed value of 0.22 He ions (cm-srs-keV/e) 1 at 0837:40-0845:00 UT on 27 August 1996 [CETAL98, Figure 3]. Based upon such misplotted data, CETAL01 stated in their introduction that CETAL98 ‘‘showed that cusp energetic ion spectra (

Recently, a new magnetospheric phenomenon, CEPevent has been discovered. This discovery has created a great avenue for the Sun-Earth connection investigations. CEP events were detected in the high-altitude cusp for hours at a time, and each of the events is associated with a dramatic decrease and large fluctuations in the local magnetic field strength. Associated with these cavities are ions with energies from 40 keV up to 8 MeV that are more typical of the trapped ring current and radiation belt populations than the solar wind. By their geometry cusp magnetic field lines are connected to all of the magnetopause boundary layers and these cusp particles will form an energetic particle layer on the magnetopause. The intensities of the energetic ions were observed to increase by as large as four orders of the magnitudes during the cusp crossings, indicating the dayside high-altitude cusp is a key region for transferring the solar wind energy, mass, and momentum into the Earth’s magnetosphere. The charge state distribution of these cusp ions is indicative of their seed populations being a mixture of the ionospheric and the solar wind particles. These CEP events together with the cusp’s connectivity have significant global impacts on the geospace environment research and have been shedding light on the long-standing unsolved fundamental issue about the origins of the energetic particles in the ring current and in the upstream ion events. New observational facts demonstrate that these cusp energetic ions drift into the nightside plasma sheet along closed field lines, populate the dayside magnetopause boundary layer along closed/open field lines, and escape into the upstream and downstream regions along open field lines.

The white balance tester is an instrument that adjusts the white balance for color TVs, monitors, and PC displays. We have designed a new white balance tester for use directly at the production line. It picks up the R (Red), G (Green), and B (Blue) signals for the screen using color sensors, compares the signals with the data previously stored in the internal memory, displays their differences with LED bars in the compare mode or displays x y Y, u v Y, JND (just noticeable difference) as well as correlated color temperature in the numerical mode. A built-in TV signal generator sets the luminance of the adjusting screen to the brightness of the reference white screen automatically. A 16-bit single chip microcomputer processes the measured values and controls the output levels of the TV signal generator.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Neutron monitor data recorded at Thule, Greenland, and McMurdo, Antarctica, are used to determine the cosmic-ray north-south anisotropy over the period 1961-1988. This anisotropy shows an 11 yr sunspot cycle variation, but it does not exhibit a dependence upon the direction of the Sun's magnetic dipole. The north-south anisotropy together with the two components of the diurnal anisotropy comprise a three-dimensional anisotropy, from which we extract detailed new information on the radial and latitudinal gradients of cosmic-ray density and the cosmic-ray scattering mean free path near Earth. We find that the bidirectional latitude gradient reverses sign with the solar magnetic polarity reversal, in accord with the predictions of drift theory, and its magnitude is generally larger during negative solar polarity than during positive polarity

Data from five neutron monitor stations and one ionization-chamber station are employed to determine the variation of the cosmic-ray diurnal anisotropy over a time span exceeding 50 years. The amplitude of the diurnal anisotropy varies with a period of one sunspot cycle, while the phase varies with a period of two sunspot cycles. Using minimum-variance analysis, it is shown that the principal axis of variation of the anisotropy is nearly aligned with the mean magnetic field, in agreement with earlier conclusions of Forbush. These results provide new information on the long-term variation of cosmic-ray gradients. Taking nominal values for the parallel and perpendicular diffusion coefficients, it is found that the value of the radial gradient during epochs of negative solar magnetic polarity is persistently larger than during positive polarity epochs, while the bidirectional latitude gradient reverses sign with the solar magnetic polarity reversal. The behavior of both gradients favors the drift theory during solar minimum periods. 70 refs.

The cosmic ray diurnal anisotropy is determined separately in toward and away sectors of the interplanetary magnetic field through analysis of neutron monitor records spanning the period 1953–1988. We suggest that the dominant cause of differences (between sectors) of the anisotropy is a unidirectional latitude gradient, which is indicative of a north-south asymmetry in the solar modulation of cosmic rays. The magnitude of the latitude gradient deduced from the observations is typically of the order of 0.7%/AU, and its direction varies in a manner not obviously related to either the 11-year sunspot cycle or the 22-year solar magnetic cycle. Further support for the reality of a unidirectional gradient is provided by an analysis of the cosmic ray density segregated according to sector polarity. The density is found to differ significantly in the two sector types, and the amount of difference is correlated with the concurrently measured unidirectional latitude gradient in the expected manner. We examine two hypotheses to account for a north-south asymmetry of solar modulation: (1) that the asymmetric modulation results from a north-south asymmetry in the winding angle of the interplanetary magnetic field spiral and (2) that the asymmetric modulation is related to a corresponding north-south asymmetry of solar activity as indicated by sunspot number. Both hypotheses are consistent with the data, suggesting that multiple factors may give rise to north-south asymmetric solar modulation.

The power law form of the two-point galaxy correlation function ξ, and a relationship between ξ and the three-point correlation function ζ, are derived theoretically. These derivations provide a theoretical basis for expressions that heretofore have been based solely upon observations of galaxy or cluster clustering.

The theoretical form of the four-point galaxy correlation function is, for the first time, derived directly from the BBGKY equations by the method of separating variables. It has the same form as that deduced from observations. The same approach is extended to five- and six-point galaxy correlation functions. A one-to-one correspondence between n -point tree symbols and n -point galaxy correlation functions is established to develop the general theoretical forms of galaxy n -point correlation functions. This theory lends further support to the continuous clustering hierarchy picture for the galaxy distribution, and for the idea that there is a remarkably simple underlying statistical pattern.