Constraining the Properties of the Multicomponent Local Interstellar Medium: MHD-kinetic Modeling Validated by Voyager and New Horizons Data
Year: 2024
Type: article
Abstract: We introduce the first solar-cycle simulations from our 3D, global MHD-plasma/kinetic-neutrals model, where both hydrogen and helium atoms are treated kinetically, while electrons and helium ions are described as individual fluids. Using Voyager/PWS observations of electron density up to 160 au from the Sun for validation of several different global models, we conclude that the current estimates for the proton density in the local interstellar medium (LISM) need a revision. Our findings indicate that the commonly accepted value of 0.054 cm−3 may need to be increased to values exceeding 0.07 cm−3. We also show how different assumptions regarding the proton velocity distribution function in the outer heliosheath may affect the global solution. A new feature revealed by our simulations is that the helium ion flow may be significantly compressed and heated in the heliotail at heliocentric distances exceeding ∼400 au. Additionally, we identify a Kelvin–Helmholtz instability at the boundary of the slow and fast solar wind in the inner heliosheath, which acts as a driver of turbulence in the heliotail. These results are crucial for inferring the properties of the LISM and of the global heliosphere structure.
Institution: University of Alabama in Huntsville
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,400
Awards: G7998775681, G8612546295, THE PLANNED PERIOD OF PERFORMANCE IS NOVEMBER 1 2017 THROUGH OCTOBER 31 2019. THE FOLLOWING ACTIVITIES WILL BE PERFORMED DURING THE EXTENDED MISSION BY PRINCETON. A. PROVIDE PI LEADERSHIP OF THE IBEX SCIENCE EFFORT THROUGHOUT THE EXTENDED MISSION B. MANAGE THE PRINCETON SCIENCE EFFORT THROUGHOUT THE EXTENDED MISSION C. PREPARE AND SUBMIT QUARTERLY TECHNICAL PROGRESS REPORTS D. SUPPORT TEAM TELECONS 1 TO 2 TIMES PER MONTH E. ATTEND SCIENCE TEAM MEETINGS AND SCIENTIFIC CONFERENCES AS CALLED BY THE PI F. DEVELOP ALGORITHMS AND SOFTWARE AS REQUEST BY THE PI IN SUPPORT OF IBEX DATA ANALYSIS OR THEORY EFFORTS G. ANALYZE AND PUBLISH IBEX INVESTIGATION SCIENCE DATA H. RECEIVE AND ANALYZE PAYLOAD SCIENCE DATA; WORK WITH THE IBEX TEAM TO DEVELOP MODELS ALGORITHMS ETC. TO ANALYZE THE SCIENCE DATA; PUBLISH IBEX SCIENCE RESULTS; SUPPORT THE ARCHIVAL OF SCIENCE DATA, Collaborative Research: Travel Supplement for Frontera's "Multi-scale, MHD-Kinetic Modeling of the Solar Wind and its Interaction with the Local Interstellar Medium"
OpenAlex ID: W4403181600