Connectivity Between Solar Energetic Particle Observations and Their Solar Sources: The Event on 14 August 2010

We analyze one of the first multi-spacecraft solar energetic particle (SEP) events of solar cycle 24 to assess the reliability of models currently used to determine the connectivity between the sources of SEPs at the Sun and spacecraft located in the inner heliosphere. This SEP event was observed on 14 August 2010 by near-Earth spacecraft, STEREO-A (at 0.96 AU from the Sun and 80° west of Earth) and STEREO-B (at 1.07 AU and 72° east of Earth). The SEP event occurred in association with a C4.4 flare at N13W54 (as seen from Earth) and a fast ( 1200 km s-1) halo coronal mass ejection (CME). Whereas near-Earth observers were magnetically connected to the site of the active region, the other spacecraft observing SEPs remained poorly connected to the active region. We discuss the properties of the phenomena associated with the solar eruption as seen in extreme ultraviolet and white-light images collected by SOHO, SDO and STEREO that allow us to specify the extent of the coronal shock associated with the CME and whether the SEPs observed at the three heliospheric locations were accelerated and injected by the shock. Alternatively, we study whether transport mechanisms in the solar corona and/or interplanetary space explain the arrival of particles to those spacecraft poorly connected to the particle sources. Finally, we discuss whether the large-scale physics-based prediction models of the heliosphere, currently used by the Space Weather Forecast Offices at NOAA and NASA/GSFC, provide a good description for the connectivity of each spacecraft with the particle sources in interplanetary space.