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- Galactic cosmic rays (2)
- Radial diffusion (2)
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- AFFINITIES (1)
- Astronomy & Astrophysics (1)
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- DINITROAROMATIC RADICAL-ANIONS (1)
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Articles 1 - 11 of 11
Full-Text Articles in Physics
Metastable Anions Of Dinitrobenzene: Resonances For Electron Attachment And Kinetic Energy Release, A. Mauracher, S. Denifl, A. Edtbauer, M. Hager, M. Probst, Olof E. Echt, T. D. Maerk, P. Scheier, T. A. Field, K. Graupner
Metastable Anions Of Dinitrobenzene: Resonances For Electron Attachment And Kinetic Energy Release, A. Mauracher, S. Denifl, A. Edtbauer, M. Hager, M. Probst, Olof E. Echt, T. D. Maerk, P. Scheier, T. A. Field, K. Graupner
Physics & Astronomy
Attachment of free, low-energy electrons to dinitrobenzene (DNB) in the gas phase leads to DNB as well as several fragment anions. DNB, (DNB-H), (DNB-NO), (DNB-2NO), and (DNB-NO(2)) are found to undergo metastable (unimolecular) dissociation. A rich pattern of resonances in the yield of these metastable reactions versus electron energy is observed; some resonances are highly isomer-specific. Most metastable reactions are accompanied by large average kinetic energy releases (KER) that range from 0.5 to 1.32 eV, typical of complex rearrangement reactions, but (1,3-DNB-H)(-) features a resonance with a KER of only 0.06 eV for loss of NO. (1,3-DNB-NO)(-) offers a rare …
Gcr Access To The Moon As Measured By The Crater Instrument On Lro, A. W. Case, Harlan E. Spence, M. J. Golightly, J. C. Kasper, J. B. Blake, J. E. Mazur, L. W. Townsend, C. J. Zeitlin
Gcr Access To The Moon As Measured By The Crater Instrument On Lro, A. W. Case, Harlan E. Spence, M. J. Golightly, J. C. Kasper, J. B. Blake, J. E. Mazur, L. W. Townsend, C. J. Zeitlin
Physics & Astronomy
[1] Recent modeling efforts have yielded varying and conflicting results regarding the possibility that Earth's magnetosphere is able to shield energetic particles of >10 MeV at lunar distances. This population of particles consists of galactic cosmic rays as well as energetic particles that are accelerated by solar flares and coronal mass ejections. The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) onboard the Lunar Reconnaissance Orbiter is in orbit about the Moon and is thus able to directly test these modeling results. Over the course of a month, CRaTER samples the upstream solar wind as well as various regions …
Evolving Outer Heliosphere: Large-Scale Stability And Time Variations Observed By The Interstellar Boundary Explorer, D. J. Mccomas, M. Bzowski, P. Frisch, G. B. Crew, M. A. Dayeh, R. Demajistre, H. O. Funsten, S. A. Fuselier, M. Gruntman, P. Janzen, M. A. Kubiak, G Livadiotis, Eberhard Moebius, D. B. Reisenfeld, Nathan A. Schwadron
Evolving Outer Heliosphere: Large-Scale Stability And Time Variations Observed By The Interstellar Boundary Explorer, D. J. Mccomas, M. Bzowski, P. Frisch, G. B. Crew, M. A. Dayeh, R. Demajistre, H. O. Funsten, S. A. Fuselier, M. Gruntman, P. Janzen, M. A. Kubiak, G Livadiotis, Eberhard Moebius, D. B. Reisenfeld, Nathan A. Schwadron
Physics & Astronomy
The first all-sky maps of Energetic Neutral Atoms (ENAs) from the Interstellar Boundary Explorer (IBEX) exhibited smoothly varying, globally distributed flux and a narrow "ribbon" of enhanced ENA emissions. In this study we compare the second set of sky maps to the first in order to assess the possibility of temporal changes over the 6 months between views of each portion of the sky. While the large-scale structure is generally stable between the two sets of maps, there are some remarkable changes that show that the heliosphere is also evolving over this short timescale. In particular, we find that (1) …
Studies Of Insulating Superconductors, Shawna M. Hollen, J C. Joy, Maura Lynch, H Q. Nguyen, M D. Stewart Jr, J Shainline, Aijun Yin, J M. Xu, J M. Valles Jr.
Studies Of Insulating Superconductors, Shawna M. Hollen, J C. Joy, Maura Lynch, H Q. Nguyen, M D. Stewart Jr, J Shainline, Aijun Yin, J M. Xu, J M. Valles Jr.
Physics & Astronomy
No abstract provided.
Structure And Oscillatory Multilayer Relaxation Of The Bismuth (100) Surface, J. Sun, J. Wang, J. Wells, Y. M. Koroteev, G. Bihlmayer, E. V. Chulkov, Ph Hofmann, Karsten Pohl
Structure And Oscillatory Multilayer Relaxation Of The Bismuth (100) Surface, J. Sun, J. Wang, J. Wells, Y. M. Koroteev, G. Bihlmayer, E. V. Chulkov, Ph Hofmann, Karsten Pohl
Physics & Astronomy
We present a combined experimental and theoretical study of the surface structure of single crystal Bi(100) via scanning tunneling microscopy (STM), low-energy electron diffraction intensity versus energy (LEED-IV) analysis and density functional theory (DFT). We find that the surface is unreconstructed and shows an unusually large oscillatory multilayer relaxation down to the sixth layer. This unexpected behavior will be explained by a novel mechanism related to the deeply penetrating electronic surface states. STM reveals wide (100) terraces, which are separated by two-layer high steps in which the shorter of the two interlayer spacings is terminating this surface, consistent with the …
Modeling Radiation Belt Radial Diffusion In Ulf Wave Fields: 2. Estimating Rates Of Radial Diffusion Using Combined Mhd And Particle Codes, Chia-Lin L. Huang, Harlan E. Spence, Mary K. Hudson, Scot R. Elkington
Modeling Radiation Belt Radial Diffusion In Ulf Wave Fields: 2. Estimating Rates Of Radial Diffusion Using Combined Mhd And Particle Codes, Chia-Lin L. Huang, Harlan E. Spence, Mary K. Hudson, Scot R. Elkington
Physics & Astronomy
[1] Quantifying radial transport of radiation belt electrons in ULF wave fields is essential for understanding the variability of the trapped relativistic electrons. To estimate the radial diffusion coefficients (DLL), we follow MeV electrons in realistic magnetospheric configurations and wave fields calculated from a global MHD code. We create idealized pressure-driven MHD simulations for controlled solar wind velocities (hereafter referred to as pressure-driven Vx simulations) with ULF waves that are comparable to GOES data under similar conditions, by driving the MHD code with synthetic pressure profiles that mimic the pressure variations of a particular solar wind velocity. The ULF wave …
Modeling Radiation Belt Radial Diffusion In Ulf Wave Fields: 1. Quantifying Ulf Wave Power At Geosynchronous Orbit In Observations And In Global Mhd Model, Chia-Lin L. Huang, Harlan E. Spence, Howard J. Singer, W. Jeffrey Hughes
Modeling Radiation Belt Radial Diffusion In Ulf Wave Fields: 1. Quantifying Ulf Wave Power At Geosynchronous Orbit In Observations And In Global Mhd Model, Chia-Lin L. Huang, Harlan E. Spence, Howard J. Singer, W. Jeffrey Hughes
Physics & Astronomy
[1] To provide critical ULF wave field information for radial diffusion studies in the radiation belts, we quantify ULF wave power (f = 0.5–8.3 mHz) in GOES observations and magnetic field predictions from a global magnetospheric model. A statistical study of 9 years of GOES data reveals the wave local time distribution and power at geosynchronous orbit in field-aligned coordinates as functions of wave frequency, solar wind conditions (Vx, ΔPd and IMF Bz) and geomagnetic activity levels (Kp, Dst and AE). ULF wave power grows monotonically with increasing solar wind Vx, dynamic pressure variations ΔPd and geomagnetic indices in a …
Galactic Cosmic Ray Radiation Hazard In The Unusual Extended Solar Minimum Between Solar Cycles 23 And 24, Nathan A. Schwadron, A. J. Boyd, K. Kozarev, M. Golightly, Harlan E. Spence, L. W. Townsend, M. Owens
Galactic Cosmic Ray Radiation Hazard In The Unusual Extended Solar Minimum Between Solar Cycles 23 And 24, Nathan A. Schwadron, A. J. Boyd, K. Kozarev, M. Golightly, Harlan E. Spence, L. W. Townsend, M. Owens
Physics & Astronomy
[1] Galactic cosmic rays (GCRs) are extremely difficult to shield against and pose one of the most severe long-term hazards for human exploration of space. The recent solar minimum between solar cycles 23 and 24 shows a prolonged period of reduced solar activity and low interplanetary magnetic field strengths. As a result, the modulation of GCRs is very weak, and the fluxes of GCRs are near their highest levels in the last 25 years in the fall of 2009. Here we explore the dose rates of GCRs in the current prolonged solar minimum and make predictions for the Lunar Reconnaissance …
Parameterizations Of The Linear Energy Transfer Spectrum For The Crater Instrument During The Lro Mission, L. W. Townsend, Y. M. Charara, N. Delauder, M. Pourarsalan, J. A. Anderson, C. M. Fisher, Harlan E. Spence, Nathan A. Schwadron, M. J. Golightly, F. A. Cucinotta
Parameterizations Of The Linear Energy Transfer Spectrum For The Crater Instrument During The Lro Mission, L. W. Townsend, Y. M. Charara, N. Delauder, M. Pourarsalan, J. A. Anderson, C. M. Fisher, Harlan E. Spence, Nathan A. Schwadron, M. J. Golightly, F. A. Cucinotta
Physics & Astronomy
[1] The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument was launched as part of the Lunar Reconnaissance Orbiter (LRO) spacecraft in June 2009. Its purpose is to measure the linear energy transfer (LET) spectrum in lunar orbit as an aid in determining risks to human crews on future lunar missions. Part of the preparations for the mission involved estimating the LET spectrum for the anticipated environment that the instrument is likely to see during the 1 year operational phase of the LRO mission. Detailed estimates of LET spectra in the six silicon detectors and two tissue equivalent …
Further Analysis Of A Cooper Pair Insulator, Shawna M. Hollen, H Q. Nguyen, M D. Stewart Jr, J Shainline, Aijun Jin, J M. Valles Jr.
Further Analysis Of A Cooper Pair Insulator, Shawna M. Hollen, H Q. Nguyen, M D. Stewart Jr, J Shainline, Aijun Jin, J M. Valles Jr.
Physics & Astronomy
No abstract provided.
Earth‐Moon‐Mars Radiation Environment Module Framework, Nathan A. Schwadron, L. Townsend, K. Kozarev, M. A. Dayeh, F. Cucinotta, M. Desai, M. Golightly, D. Hassler, R. Hatcher, M. Y. Kim, A. Posner, M. Pourarsalan, Harlan E. Spence, R. K. Squier
Earth‐Moon‐Mars Radiation Environment Module Framework, Nathan A. Schwadron, L. Townsend, K. Kozarev, M. A. Dayeh, F. Cucinotta, M. Desai, M. Golightly, D. Hassler, R. Hatcher, M. Y. Kim, A. Posner, M. Pourarsalan, Harlan E. Spence, R. K. Squier
Physics & Astronomy
[1] We are preparing to return humans to the Moon and setting the stage for exploration to Mars and beyond. However, it is unclear if long missions outside of low-Earth orbit can be accomplished with acceptable risk. The central objective of a new modeling project, the Earth-Moon-Mars Radiation Exposure Module (EMMREM), is to develop and validate a numerical module for characterizing time-dependent radiation exposure in the Earth-Moon-Mars and interplanetary space environments. EMMREM is being designed for broad use by researchers to predict radiation exposure by integrating over almost any incident particle distribution from interplanetary space. We detail here the overall …