First Light with ALES: A 2-5 Micron Adaptive Optics Integral Field Spectrograph for the LBT

TL;DR

ALES is a pioneering 3-5 micron integral field spectrograph installed on the LBT, enabling enhanced exoplanet imaging and characterization in a wavelength range where self-luminous exoplanets are brightest.

Contribution

This paper introduces ALES, the first 3-5 micron integral field spectrograph for exoplanet imaging, with a modular design and successful first light at LBT in 2015.

Findings

First light achieved at LBT in June 2015

Operates in 3-5 micron range for exoplanet imaging

Modular optical design with new components

Abstract

Integral field spectrographs are an important technology for exoplanet imaging, due to their ability to take spectra in a high-contrast environment, and improve planet detection sensitivity through spectral differential imaging. ALES is the first integral field spectrograph capable of imaging exoplanets from 3-5$\mu$m, and will extend our ability to characterize self-luminous exoplanets into a wavelength range where they peak in brightness. ALES is installed inside LBTI/LMIRcam on the Large Binocular Telescope, taking advantage of existing AO systems, camera optics, and a HAWAII-2RG detector. The new optics that comprise ALES are a Keplerian magnifier, a silicon lenslet array with diffraction suppressing pinholes, a direct vision prism, and calibration optics. All of these components are installed in filter wheels making ALES a completely modular design. ALES saw first light at the LBT in June 2015.