Interaction of CME/ICME with HSS solar wind from coronal holes: case study

TL;DR

This study investigates how coronal hole high-speed streams interact with CMEs/ICMEs, revealing that such interactions can cause deflections and modifications in solar wind streams, affecting space weather predictions.

Contribution

It provides a detailed case study analysis of CME/ICME and HSS interactions during specific Carrington rotations, highlighting the impact on solar wind behavior.

Findings

Interaction can cause significant HSS deflection from the Sun-Earth line.

Different interaction scenarios lead to varied solar wind signatures.

Coronal hole passage with nearby CMEs influences solar wind parameters.

Abstract

In this paper we look for traces of interaction of CME/ICME with high-speed stream (HSS) of solar wind from coronal hole (CH) for two serial Carrington rotations (CRs) during December 2011 - January 2012. We analyze two cases. (1) In CR 2118 instead of predicted arrival of HSS the signatures of ICME with modified back side and compressed slow stream were observed. (2) In CR 2119 the predicted HSS was observed in time, and after arrival of preceding ICME. Our analysis shows that difference of these cases can be explained by different interactions between HSS and CME, which in the first case result in significant deflection of HSS of solar wind from the Sun-Earth line. Thus, the CH passage through the central meridian with simultaneous occurrence of CMEs in the nearby located sources can result in interaction between HSS and CME streams, deflection of the HSS stream aside of the ecliptic and changes in parameters of the solar wind.