Towards a mid-infrared L band up-conversion interferometer: first on-sky sensitivity test on a single arm. Issue 3 (14th March 2019)

• Record Type: Journal Article
• Authors: Lehmann, Lucien; Grossard, Ludovic; Delage, Laurent; Reynaud, François; Chauvet, Mathieu; Bassignot, Florent; Martinache, Frantz; Morand, Frédéric; Rivet, Jean-Pierre; Schmider, François-Xavier; Vernet, David
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 485:Issue 3(2019)
• Page Start: 3595
• Page End: 3599
• Publication Date: 2019-03-14
• Subjects: instrumentation: detectors -- instrumentation: high angular resolution -- techniques: interferometric; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stz729
• Languages: English
• ISSNs: 0035-8711

Abstract

Abstract: We report on the first on-sky sensitivity test on a single arm of the Astronomical Light Optical Hybrid Analysis (ALOHA) instrument, an uncooled up-conversion interferometer in the L band (3.5 $\mu$ m). Despite a low coupling efficiency (in the range of 1 per cent) between the 1-m class telescope and our instrument, we detect a magnitude L mag = 2.8 star with a signal-to-noise ratio SNR = 2.7 over a 30 min integration time and with a spectral resolution λ/Δλ = 100. As the ALOHA project aims to shift light from the L band to the near-infrared, the use of very low loss silica optical fibres is an important step towards fibre-linked very long-baseline interferometry in the mid-infrared.