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arXiv · 0807.0164

Imaging the dense stellar cluster R136 with VLT-MAD

M. A. Campbell·C. J. Evans·J. Ascenso·A. J. Longmore·J. Kolb·M. Gieles·J. Alves
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Abstract

We evaluate the performance of the Multi-conjugate Adaptive optics Demonstrator (MAD) from H and Ks imaging of 30 Doradus in the Large Magellanic Cloud. Maps of the full-width half maximum (FWHM) of point sources in the H and Ks images are presented, together with maps of the Strehl ratio achieved in the Ks-band observations. Each of the three natural guide stars was at the edge of the MAD field-of-view, and the observations were obtained at relatively large airmass (1.4-1.6). Even so, the Strehl ratio achieved in the second pointing (best-placed compared to the reference stars) ranged from 15% to an impressive 30%. Preliminary photometric calibration of the first pointing indicates 5 sigma sensitivities of Ks=21.75 and H=22.25 (from 22 and 12 min exposures, respectively).

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M. A. Campbell, C. J. Evans, J. Ascenso, A. J. Longmore, J. Kolb, M. Gieles, J. Alves. 2008-07-01. Imaging the dense stellar cluster R136 with VLT-MAD. https://doi.org/10.1117/12.788964

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