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arXiv · 1509.00129

First Light Results from the Hermes Spectrograph at the AAT

Andrew Sheinis·Borja Anguiano·Martin Asplund·Carlos Bacigalupo·Sam Barden·Michael Birchall·Joss Bland-Hawthorn·Jurek Brzeski·Russell Cannon·Daniela Carollo·Scott Case·Andrew Casey·Vladimir Churilov·Couch Warrick·Robert Dean·Gayandhi De Silva·Valentina D'Orazi·Ly Duong·Tony Farrell·Kristin Fiegert·Kenneth Freeman·Frost Gabriella·Luke Gers·Michael Goodwin·Doug Gray·Andrew Green·Ron Heald·Jeroen Heijmans·Michael Ireland·Damien Jones·Prajwal Kafle·Stefan Keller·Urs Klauser·Yuriy Kondrat·Janez Kos·Jon Lawrence·Steve Lee·Slavko Mali·Sarah Martell·Darren Mathews·Don Mayfield·Stan Miziarski·Rolf Muller·Naveen Pai·Robert Patterson·Ed Penny·David Orr·Katharine Schlesinger·Sanjib Sharma·Keith Shortridge·Jeffrey Simpson·Scott Smedley·Greg Smith·Darren Stafford·Nicholas Staszak·Minh Vuong·Lewis Waller·Elizabeth Wylie de Boer·Pascal Xavier·Jessica Zheng·Ross Zhelem·Daniel Zucker·Tomaz Zwitter
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Abstract

The High Efficiency and Resolution Multi Element Spectrograph, HERMES, is a facility-class optical spectrograph for the Anglo-Australian Telescope (AAT). It is designed primarily for Galactic Archaeology, the first major attempt to create a detailed understanding of galaxy formation and evolution by studying the history of our own galaxy, the Milky Way. The goal of the GALAH survey is to reconstruct the mass assembly history of the Milky Way through a detailed chemical abundance study of one million stars. The spectrograph is based at the AAT and is fed by the existing 2dF robotic fiber positioning system. The spectrograph uses volume phase holographic gratings to achieve a spectral resolving power of 28,000 in standard mode and also provides a high-resolution mode ranging between 40,000 and 50,000 using a slit mask. The GALAH survey requires an SNR greater than 100 for a star brightness of V ?= 14 in an exposure time of one hour. The total spectral coverage of the four channels is about 100 nm between 370 and 1000 nm for up to 392 simultaneous targets within the 2-degree field of view. HERMES has been commissioned over three runs, during bright time in October, November, and December 2013, in parallel with the beginning of the GALAH pilot survey, which started in November 2013. We present the first-light results from the commissioning run and the beginning of the GALAH survey, including performance results such as throughput and resolution, as well as instrument reliability.

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Andrew Sheinis, Borja Anguiano, Martin Asplund, Carlos Bacigalupo, Sam Barden, Michael Birchall, Joss Bland-Hawthorn, Jurek Brzeski, Russell Cannon, Daniela Carollo, Scott Case, Andrew Casey, Vladimir Churilov, Couch Warrick, Robert Dean, Gayandhi De Silva, Valentina D'Orazi, Ly Duong, Tony Farrell, Kristin Fiegert, Kenneth Freeman, Frost Gabriella, Luke Gers, Michael Goodwin, Doug Gray, Andrew Green, Ron Heald, Jeroen Heijmans, Michael Ireland, Damien Jones, Prajwal Kafle, Stefan Keller, Urs Klauser, Yuriy Kondrat, Janez Kos, Jon Lawrence, Steve Lee, Slavko Mali, Sarah Martell, Darren Mathews, Don Mayfield, Stan Miziarski, Rolf Muller, Naveen Pai, Robert Patterson, Ed Penny, David Orr, Katharine Schlesinger, Sanjib Sharma, Keith Shortridge, Jeffrey Simpson, Scott Smedley, Greg Smith, Darren Stafford, Nicholas Staszak, Minh Vuong, Lewis Waller, Elizabeth Wylie de Boer, Pascal Xavier, Jessica Zheng, Ross Zhelem, Daniel Zucker, Tomaz Zwitter. 2015-09-01. First Light Results from the Hermes Spectrograph at the AAT. https://doi.org/10.1117/12.2234334

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