Last Gasp? No, First GASP!

In July, Gemini South hosted a new visiting instrument, the Galway Astronomical Stokes Polarimeter (GASP). GASP is a unique instrument, unlike anything else on Gemini. This ultra-high-speed imaging polarimeter simultaneously measures both linear and circular

polarisation on times scales down to 0.5 msec. This provides a means to measure magnetic field geometry and strength, as well as asymmetries in radiation production and transmission, in sources ranging from active galactic nuclei to compact binary systems and neutron stars. Fast polarimetry permits the team to study stochastic or periodic variability on short timescales, and Gemini has the light-collecting capability to allow very short integration times.

For this first visit, the schedule was quite compressed, with assembly in Chile, integration to the telescope (including the installation of their own GPS system to permit accurate timing for the very fast observations), and the science time allocated by the ITAC all compressed into just a few days. This was made possible by the outstanding instrument team, PI Andy Shearer and Nicholas Devaney (both from NUI Galway) and Christian Gouiffès (CEA Saclay), and by the dedicated and skilled staff at Gemini South, led by Electronics Engineer Assistant Mariah Birchard, Science Fellow Erik Dennihy, and including Javier Fuentes, Manuel Gomez, Vicente Vergara and their teams.

With the success of this project, we hope to be able to invite GASP back in the future for more exciting electromagnetic exploration!