Exciting times for LUCI1! After receiving its first light corrected by the Ground Layer Adaptive Optics ARGOS system (see our previous post), LUCI1 was again on the spot for a few nights of commissioning in Adaptive Optics (AO) mode, this time with a full AO correction not limited to low atmospheric layers of the atmosphere.
Much work was done by the LUCI team to reach this important step. LUCI1 was retrofitted with a new detector (the same as in LUCI2) in the Fall of 2015. A new camera (N30) was also installed, designed to provide the image quality and sampling required to exploit the exquisite resolution delivered by the LBT adaptive secondary mirrors. LUCI1 looks much alike LUCI2, though its N30 camera is made of glass mirrors instead of metal mirrors for the LUCI2 N30 camera.
The LBT adaptive secondaries were unavailable for most of the last semester and came back on the telescope late in 2015 (left side – SX) and in early February (right side – DX). Thanks to the combined efforts of LBTO staff and the Arcetri AO team, the SX secondary was back in service and a first set of LUCI1 NCPA (non common path aberrations) measurements was determined just before the LUCI1-AO commissioning run. The commissioning was therefore a mix of AO checkout and LUCI1-AO observations.
The image of M5 above was taken with LUCI1 and FLAO in Ks-band on March 21 2016. Integration time is 11min. The brightest star in the field, with an R+I magnitude of 10.4, was used as reference star for the AO correction. The AO correction was obtained with 153 modes. Ambient seeing was around 0.9”. The images close to the reference star have a FWHM of around 66mas.
Interestingly enough, as seen in the above graph, the image quality is pretty constant over a ~17″ radius from the AO reference star.
The next LUCI1 commissioning run is scheduled for April 2016. Stay tuned…
The following step will be to return to LUCI2, which saw first AO light in early 2015 (see here), for commissioning of its AO spectroscopic mode.
With the addition of AO and ARGOS modes, coupled with routine binocular observations, we expect that the LUCIs will be heavily in use by early 2017, and will be a major contributor to the scientific productivity of the Observatory.
Congratulations go to the LUCI team for an excellent work in the midst of the adaptive secondaries struggles of these past months, and to the LBTO and Arcetri AO teams for their support!