Following the interstellar magnetic field from the heliosphere into space with polarized starlight

15th Annual International Astrophysics Conference: "The Science of Ed Stone: Celebrating his 80th Birthday"

物理学;天文学

Frisch, P.C.^1 ; Berdyugin, A.B.^2 ; Piirola, V.^2 ; Magalhaes, A.M.^3 ; Seriacopi, D.B.^3 ; Ferrari, T.^3 ; Santos, F.P.^4 ; Schwadron, N.A.^5 ; Funsten, H.O.^6 ; McComas, D.J.^7 ; Heiles, C.E.^8

Department of Astronomy and Astrophysics, University of Chicago, Chicago

IL

60637, United States^1

Tuorla Observatory, Finnish Centre for Astronomy with ESO, University of Turku, Finland^2

Inst. de Astronomia, Geofisica e Ciencias Atmosfericas, Universidade de Sao Paulo, Sao Paulo, Brazil^3

Center for Interdisciplinary Exploration and Research in Astrophysics, Department of Physics and Astronomy, Northwestern University, Evanston

IL

60208, United States^4

Space Science Center, University of New Hampshire, NH

03824, United States^5

Los Alamos National Laboratory, Los Alamos

NM

87544, United States^6

Princeton Plasma Physics Lab, Princeton University, Princeton

NJ

08543, United States^7

Astronomy Department, University of California, CA

94720, United States^8

关键词: Data accuracy;    High probability;    Interstellar clouds;    Interstellar dust;    Interstellar magnetic fields;    Linearly polarized;    Position angle;    Statistical probability;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/767/1/012010/pdf
DOI  :  10.1088/1742-6596/767/1/012010

学科分类：天文学(综合)

来源: IOP

【 摘 要 】

Starlight linearly polarized by aligned interstellar dust grains provides the necessary data for tracing the structure of the very local interstellar magnetic field (ISMF). Two methods have been developed to recover the ISMF direction from polarized starlight, using data from an ongoing polarization survey. Both methods rely on the probability distribution function for polarized light. Method 1 calculates the ISMF direction from polarization position angles regardless of the data accuracy, while Method 2 relies on high-probability data points. The ISMF directionBibex recovered by Method 1 corresponds to the closest ISMF to the heliosphere, traced by the center of the IBEX Ribbon arc. Method 2 reveals a new direction for the more distant ISMF, Bnew, toward l=41.1° ± 4.1° and b= 25.8° ± 3.0°, which differs by 30.4° ± 5.6° from the IBEX ISMF direction. Polarizations of filament stars that are located within 25° of a pole of Bnew, where background polarizations would be minimal, show the highest statistical probabilities of tracing the filament ISMF. The IBEX ISMF direction orders the kinematics of interstellar clouds within 15 pc, and Bnewmust therefore dominate beyond 15 pc. These new data are consistent with the location of the Sun in the rim of an expanding superbubble shell associated with the evolved Loop I superbubble.