Use of an extremely large telescope for HTRA

Investigative studies have designed concept instruments for a proposed 42 m European Extremely Large Telescope (E-ELT) facility suite. An ELT will aid, at its most basic level, detection of the faintest stellar sources and instrinsic features, and detailed quantitative analysis of relatively bright sources. The development of such a telescope thus plays to the strengths of high time resolution (HTR) detectors which provide single photon detection capabilities and or extremely high refresh rates-they can maximize detection of faint sources through photon counting and they can cope with the high photon flux from relatively bright objects building up extremely high S N. Specific considerations and fast detectors then need to be adopted into the ELT design to accommodate high time resolution astrophysics (HTRA) efficiently. No one instrument or detector can cover all HTRA timescales (nanoseconds to seconds and slower), and a dedicated facility HTRA instrument on the ELT is unlikely as yet, but chosen facility instruments can include HTRA options in their packages. Currently there are numerous HTRA options in existing telescope facilities around the world as well as many visiting HTRA instruments. This demonstrates an active HTRA community with worldwide support and interest in HTRA observation capabilities, which underscores the need for HTR capabilities to be designed into the ELT.