Modeling of diffuse auroral emission at Mars: Contribution of MeV protons

AbstractIn gradual Solar Energetic Particle (SEP) events, shock waves driven by coronal mass ejections (CMEs) play a major role in accelerating particles, and the energetic particle flux enhances substantially when the shock front passes by the observer. Such enhancements are historically referred to as Energetic Storm Particle (ESP) events, but it remains unclear why ESP time profiles vary significantly from event to event. In some cases, energetic protons are not even clearly associated with shocks. Here, we report an unusual, short-duration proton event detected on 5 June 2011 in the compressed sheath region bounded by an interplanetary shock and the leading edge of the interplanetary CME (or ICME) that was driving the shock. While < 10 MeV protons were detected already at the shock front, the higher-energy (> 30 MeV) protons were detected about four hours after the shock arrival, apparently correlated with a turbulent magnetic cavity embedded in the ICME sheath region.

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SPALLATION YIELDS FROM HIGH ENERGY PROTON BOMBARDMENT OF HEAVY ELEMENTS

Canadian Journal of Physics ◽

10.1139/p57-003 ◽

1957 ◽

Vol 35 (1) ◽

pp. 21-37 ◽

Cited By ~ 15

Author(s):

J. D. Jackson

Keyword(s):

Cross Sections ◽

High Energy ◽

Heavy Elements ◽

Collective Effects ◽

Comparison With Experiment ◽

Energy Proton ◽

Stringent Test ◽

Neutron Evaporation ◽

Nuclear Processes ◽

Mev Protons

The Monte Carlo calculations of McManus and Sharp (unpublished) for the prompt nuclear processes occurring upon bombardment of heavy elements by 400 Mev. protons are combined with a description of the subsequent neutron evaporation to determine spallation cross sections for comparison with experiment. The model employed is a schematic one which suppresses the detailed characteristics of individual nuclei, but gives the over-all behavior to be expected. Many-particle and collective effects such as alpha particle emission and fission are ignored. The computed cross sections are presented in a variety of different graphical forms which illustrate quantitatively the qualitative picture of high energy reactions first given by Serber (1947). The calculations are in general agreement with existing data when fission is not an important effect, but the agreement does not imply a very stringent test of the various features of the model.

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Micro-PIXE with 3.5 MeV protons for the study of low copper concentrations in atherosclerotic artery

Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms ◽

10.1016/j.nimb.2021.04.001 ◽

2021 ◽

Vol 497 ◽

pp. 34-38

Author(s):

M.D. Ynsa ◽

J. Ripoll-Sau ◽

T. Osipowicz ◽

M.B.H. Breese ◽

Minqin Ren

Keyword(s):

Mev Protons

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Anomalous Beam Transport through Gabor (Plasma) Lens Prototype

Applied Sciences ◽

10.3390/app11104357 ◽

2021 ◽

Vol 11 (10) ◽

pp. 4357

Author(s):

Toby Nonnenmacher ◽

Titus-Stefan Dascalu ◽

Robert Bingham ◽

Chung Lim Cheung ◽

Hin-Tung Lau ◽

...

Keyword(s):

Cost Effective ◽

Stable Operation ◽

High Electron ◽

Beam Transport ◽

Focusing Effect ◽

Energy Proton ◽

Diocotron Instability ◽

Strong Focusing ◽

Axis Rotation ◽

Mev Protons

An electron plasma lens is a cost-effective, compact, strong-focusing element that can ensure efficient capture of low-energy proton and ion beams from laser-driven sources. A Gabor lens prototype was built for high electron density operation at Imperial College London. The parameters of the stable operation regime of the lens and its performance during a beam test with 1.4 MeV protons are reported here. Narrow pencil beams were imaged on a scintillator screen 67 cm downstream of the lens. The lens converted the pencil beams into rings that show position-dependent shape and intensity modulation that are dependent on the settings of the lens. Characterisation of the focusing effect suggests that the plasma column exhibited an off-axis rotation similar to the m=1 diocotron instability. The association of the instability with the cause of the rings was investigated using particle tracking simulations.

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Positron emitter depth distribution in PMMA irradiated with 130 MeV protons measured using TOF-PET detectors.

IEEE Transactions on Radiation and Plasma Medical Sciences ◽

10.1109/trpms.2021.3084953 ◽

2021 ◽

pp. 1-1

Author(s):

Mythra Varun Nemallapudi ◽

Atiq Rahman ◽

Augustine Ei-Fong Chen ◽

Shih-Chang Lee ◽

Chih-Hsun Lin ◽

...

Keyword(s):

Depth Distribution ◽

Positron Emitter ◽

Pet Detectors ◽

Mev Protons ◽

Tof Pet

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Cloud Cover and Aurora Contamination at Dome A in 2017 from KLCAM

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3824 ◽

2020 ◽

Author(s):

Xu Yang ◽

Zhaohui Shang ◽

Keliang Hu ◽

Yi Hu ◽

Bin Ma ◽

...

Keyword(s):

Cloud Cover ◽

Emission Lines ◽

Austral Winter ◽

Site Testing ◽

Dome A ◽

Astronomical Observations ◽

Auroral Emission ◽

Long Term Monitoring ◽

Term Monitoring

Abstract Dome A in Antarctica has many characteristics that make it an excellent site for astronomical observations, from the optical to the terahertz. Quantitative site testing is still needed to confirm the site’s properties. In this paper, we present a statistical analysis of cloud cover and aurora contamination from the Kunlun Cloud and Aurora Monitor (KLCAM). KLCAM is an automatic, unattended all-sky camera aiming for long-term monitoring of the usable observing time and optical sky background at Dome A. It was installed at Dome A in January 2017, worked through the austral winter, and collected over 47,000 images over 490 days. A semi-quantitative visual data analysis of cloud cover and auroral contamination was carried out by five individuals. The analysis shows that the night sky was free of clouds for 83 per cent of the time, which ranks Dome A highly in a comparison with other observatory sites. Although aurorae were detected somewhere on an image for nearly 45 per cent of the time, the chance of a point on the sky being affected by an aurora is small. The strongest auroral emission lines can be filtered out with customized filters.

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