  In a thorough study, we investigate the origin of a remarkable plasma and
magnetic field configuration observed in situ on June 22, 2011 near L1, which
appears to be a magnetic ejecta (ME) and a shock signature engulfed by a solar
wind high-speed stream (HSS). We identify the signatures as an Earth-directed
coronal mass ejection (CME), associated with a C7.7 flare on June 21, 2011, and
its interaction with a HSS, which emanates from a coronal hole (CH) close to
the launch site of the CME. The results indicate that the major interaction
between the CME and the HSS starts at a height of 1.3 Rsun up to 3 Rsun. Over
that distance range, the CME undergoes a strong north-eastward deflection of at
least 30 degrees due to the open magnetic field configuration of the CH. We
perform a comprehensive analysis for the CME-HSS event using multi-viewpoint
data (from the Solar TErrestrial RElations Observatories, the Solar and
Heliospheric Observatory and the Solar Dynamics Observatory), and combined
modeling efforts (nonlinear force-free field modeling, Graduated Cylindrical
Shell CME modeling, and the Forecasting a CMEs Altered Trajectory ForeCAT
model). We aim at better understanding its early evolution and interaction
process as well as its interplanetary propagation and related in situ
signatures, and finally the resulting impact on the Earth's magnetosphere.
