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Study on Test-Mass Charging for Taiji Gravitational Wave Observatory
Han, Ruilong; Cai, Minghui; Yang, Tao +8 more
Taiji is proposed as a space-based gravitational wave (GW) observatory consisting of three spacecraft in a heliocentric orbit meanwhile with the distance of 3 million kilometers ahead of the Earth at about 20°. Free-falling test masses (TMs) are a key component of the interferometer for space-based GW detection in the 0.1mHz-1 Hz frequency range. …
Long-Term Variation of the Galactic Cosmic Ray Radiation Dose Rates
Qin, G.; Shen, Z. -N.; Lyu, D.
In this work, a model for calculating the galactic cosmic rays (GCRs) radiation dose rate is developed. The model is based on a GCR modulation model, which is established by Shen and Qin, and the fluence-dose conversion coefficients (FDCCs) published by the International Commission on Radiological Protection (ICRP). With the model, the radiation a…
Neural Networks for Operational SYM-H Forecasting Using Attention and SWICS Plasma Features
Muñoz, Pablo; Cid, Consuelo; Collado-Villaverde, Armando
In this work, we present an Artificial Neural Network for operational forecasting of the SYM-H geomagnetic index up to 2 hr ahead using the Interplanetary Magnetic Field, the solar wind plasma features and previous SYM-H values. Former works that forecast the SYM-H index use data measured by ACE, in particular from the MAG and SWEPAM instruments. …
A Surrogate Model for Studying Solar Energetic Particle Transport and the Seed Population
Schwadron, Nathan A.; Baydin, Atilim Guneş; Poduval, Bala
The high energy particles originating from the Sun, known as solar energetic particles (SEPs), contribute significantly to the space radiation environment, posing serious threats to astronauts and scientific instruments on board spacecraft. The mechanism that accelerates the SEPs to the observed energy ranges, their transport in the inner heliosph…
Improving Multiday Solar Wind Speed Forecasts
Arge, C. N.; Henney, C. J.; Dayeh, M. A. +4 more
We analyze the residual errors for the Wang-Sheeley-Arge (WSA) solar wind speed forecasts as a function of the photospheric magnetic field expansion factor (fp) and the minimum separation angle (d) in the photosphere between the footpoints of open field lines and the nearest coronal hole boundary. We find the map of residual speed error…
A Multi-Purpose Heliophysics L4 Mission
Solanki, S. K.; Arge, C. N.; Henney, C. J. +13 more
The Earth-Sun Lagrangian point 4 is a meta-stable location at 1 AU from the Sun, 60° ahead of Earth's orbit. It has an uninterrupted view of the solar photosphere centered on W60, the Earth's nominal magnetic field connection to the Sun. Such a mission on its own would serve as a solar remote sensing observatory that would oversee the entire solar…
MHD Modeling of the Background Solar Wind in the Inner Heliosphere From 0.1 to 5.5 AU: Comparison With In Situ Observations
Wang, C.; Li, H.; Guo, X. C. +4 more
The accurate prediction of solar wind conditions in the interplanetary space is crucial in the context of both scientific research and technical applications. In this study, we simulate the solar wind throughout the heliosphere from 0.1 to 5.5 astronomical units (AU) with our improved heliospheric magnetohydrodynamics (MHD) model during the time p…
Improving Predictions of High-Latitude Coronal Mass Ejections Throughout the Heliosphere
Rodriguez, L.; Poedts, S.; Scolini, C. +2 more
Predictions of the impact of coronal mass ejections (CMEs) in the heliosphere mostly rely on cone CME models, whose performances are optimized for locations in the ecliptic plane and at 1 AU (e.g., at Earth). Progresses in the exploration of the inner heliosphere, however, advocate the need to assess their performances at both higher latitudes and…
Modeling observations of solar coronal mass ejections with heliospheric imagers verified with the Heliophysics System Observatory
Rodriguez, L.; Zhang, T. L.; Möstl, C. +19 more
We present an advance toward accurately predicting the arrivals of coronal mass ejections (CMEs) at the terrestrial planets, including Earth. For the first time, we are able to assess a CME prediction model using data over two thirds of a solar cycle of observations with the Heliophysics System Observatory. We validate modeling results of 1337 CME…
Earth-Moon-Mars Radiation Environment Module framework
Schwadron, N. A.; Posner, A.; Dayeh, M. A. +11 more
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 nu…