Modelling the March 2012 solar events and their impacts at Voyager 1 in the vicinity of the heliopause

[摘要] Using our three dimensional (3D) time-dependent kinematic HAFSS model we propagate the March 2012 solar events from the Sun to Voyager 1 (V1) to investigate if these solar events could be responsible for the V1 April-May 2013 Plasma Wave Spectrometer (PWS) measurements of enhanced 2-3 kHz signals. These PWS measurements provided the basis for the confirmation that V1 entered the interstellar medium (ISM). These enhanced PWS signals also were associated with significantly increased plasma densities consistent with expectations for the ISM. The origin of these enhanced plasma densities was attributed to the April-May 2013 arrival at the heliopause of the disturbances associated with the March 2012 solar events. Using HAFSS we propagate from the Sun the March 2012 solar wind ambient background and the solar wind impulsive events for comparisons with in-situ spacecraft measurements at Earth, V1 (at 34 degrees North), and Voyager 2 (at 30 degrees South). The in-situ measurements of the March 2012 events were obtained over a wide range in radial distance, longitude, and latitude. This emphasizes the importance of using a 3D time-dependent model that originates at the Sun. From our analyses we conclude that the March 2012 solar events could have been responsible for the April-May 2013 V1 enhanced plasma wave signals and their associated increased plasma densities measured by the PWS indicating V1 was in the ISM.

[发布机构] Carmel Research Center, Santa Monica; CA; 90406, United States^1;University of Alaska, Fairbanks; AK; 99775, United States^2;New Mexico State University, Las Cruces; NM; 88003, United States^3;Bangor University, Bangor; LL57 2TT, United Kingdom^4

[效力级别] 天文学 [学科分类] 天文学(综合)

[关键词] Impulsive Events;In-situ measurement;Interstellar mediums;Measurements of;Radial distance;Threedimensional (3-d);Time dependent;Time-dependent models