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These are some images with both sides of the LBT AO system in operation.

We also took some initial data with the apodizing phase plates.

Big step. We closed both AO loops last night, and found fringes. The tight images allowed us to see the three-lobe characteristic PSF at both 4.0 and 10.6 microns. Images are below.

The image above has a pixel scale of 11 mas. The short exposure image (0.087 s) was taken at 4 microns using the LMIRcam system within LBTI. Both AO systems were locked in mediocre seeing (~1.6").

The image above has a pixel scale of 18 mas. This is a short exposure image (0.029 s) taken at 10.6 microns. The two images above were taken essentially simultaneously (slight tweaking was done for a focus shift between the cameras). This illustrates the potential of LBTI to acquire simultaneous images from 2-25 microns.

The evening started out with a promise of clear skies.

We opened at 6:30 pm and started acquisition of a bright star for alignment, AO checkout, and focus. The winds were between 15 & 18 m/s.

Within moments the humidity was on the rise. Apparently a very moist airmass was passing overhead. Even though there were few clouds the humidity quickly reached 95% and we were again forced to close the dome. You could smell the moisture in the air if you stepped outside. The moisture was also very evedent on the all-sky camera which completely fogged over.

We were back open in about an hour. In the mean time we had the opportunity to sing HAPPY BIRTHDAY to Phil and enjoy cupcakes.

Seeing was terrible after we opened back up. However we did accomplish quite a bit:

SX AO System

√ Acquire star

√ Close loop (10 modes)

DX AO System

√ Acquire star

√ Close loop (200 modes)

NOMIC

√ Acquire both SX and DX stars

√ Focus

LMIRCam

√ Acquire DX & SX star

√ Focus

√ Phase

PhaseCam

√ First Light

√ Acquire fast frame data (phasing)

√ Acquire full frame data (acquisition)

Late Afternoon:

Arrived at the LBTO at 6pm with the night's activities in full swing. The dome was open and the observing team were finishing the fine alignment of the science camera. It is always impressive to be in the dome with the shutter doors open.

We spent a productive if not frustrating first part of the evening checking out the cameras, hunting for holes in the clouds, and debugging the AO operations. We had assistance from Doug Miller in Tucson, who with the help of Armando Richardi was able to get the SX side working. There were issues that were identified and our colleagues at Arcetri were just arriving at work to help out with the issues.

Unfortunately we were forced to closed the dome at 1:30 am due to high winds. The protocol is more than one gust over 22m/s in a 6 minute time window. The baseline wind speed was ~18m/s so I think that we were lucky to stay open as long as we did. It was a productive, but short night.

Picked up Jarron Leisenring at the airport on my way to the LBTO. Jarron is from Zurich ETH and has some science time this run.

While waiting at the grocery in Wilcox. I was noting the sky conditions above the Pinaleno Mountains.

We have 2 1/2 nights for commissioning and 1 1/2 night for science starting on the 9th.

We have a large contingent at the LBTO this time around.

April 9: Phil Hinz and Vanessa Bailey

April 10-14: Phil Hinz, Vanessa Bailey, Bill Hoffmann, Vidhya Vaithseewaran, Rafael Millan-Gabet, Jarron Leisenring, Tom McMahon

Schedule:

2 hours on April 9 to "wake up" the instrument. During this time Phil and Vanessa will work at bringing the SX AO Secondary online as well as checking the LMIRCamera, NOMIC, and PhaseCam.

LBTI has four nights allocated on the LBT from UT April 11 through UT April 14.

On UT April 11 we verified that the right side AO system was working, copointed the telescope, and equalized the pathlengths. We also saw first starlight on the NOMIC detector. We had to close for winds at around 1 am.

On UT April 12 we tested the left side AO system, but had to close almost immediately for humidity and winds.

Attached is the latest revision to the 'NIC Wheel Positions' PowerPoint file... v3.6. It includes the changes that were made to the NAC wheel, Beam Diverter slide, NOMIC filter wheels, NOMIC pupil wheel, NOMIC Field Stop slide, LMIRCam filter wheels, LMIRCam Field Stop wheel, and new pics of all the wheels. The changes were performed in the LBT cleanroom on March 19-23, 2012. The 'Comments' sections for each slide have been updated with the most recent changes to that slide.

Last week, Vanessa Bailey, Vidhya Vaitheeswaran and I aligned and calibrated the LBTI wavefront sensor on the left side of LBT. This involves putting a retroreflector at prime focus and using an artificial source to measure known deformation of the adaptive secondary with the wavefront sensor. With the help of Alfio Puglisi and Enrico Pinna, we successfully calibrated the system to correct up to 400 K-L modes. The graph below shows an analysis of the AO performance for the 400 modes. The red line shows artificial turbulence introduced into the system, and the white line is the residual left (in nm RMS wavefront error) after correction.

We also calibated the system for faint stars, so that we should be able to lock on guide stars down to R=16-17, based on experience with the FLAO system.

We did get a bit of on-sky time in January to test phasing of LBTI. Below is an image at 3.7 microns of a calibrator star after adjusting pathlengths to equalize the delay. This was a 30 ms exposure to freeze the seeing. AO was operating on one side, but the other side was seeing-limited. Unfortunately, the images are saturated, so it's difficult to see the PSF.

Over the December-February span we have begun testing the 8-13 micron science channel, referred to as the Nulling-Optimized Mid-Infrared Camera (NOMIC). Below is an early screenshot of an image. The scene is a pinhole grid in the focal plane. Dual-aperture PSF's can be seen, but vignetting in the pupil plane is limiting the image quality. This vignetting is in the process of being fixed. There are also minor clocking porblems with the detector, resulting in boundary effects between the 128 row x 512 column readout blocks.

I forgot to post the picture when it happened, but the LBTI platforms were completed in early March. These were the best models we could find (Manny Montoya, Mitch Nash, and Tom Connors).

Andy Skemer and T.J. Rodigas recently submitted the first two papers from LBTI data. The images below show the planetary system HR 8799 and the edge-on disk HD 15115.

We are on our first night of a four night block to continue testing LBTI, and taking single aperture science observations. Due to clouds and high winds, we have been unable to open.

So, we developed a procedure to align the interferometer to the telescope with the dome closed. The image below shows the two LBT pupils imaged in LMIRCam, centered in the pupils of the LBTI beamcombiner. The cold dome provides a temperature contrast at 4.8 microns, that makes it appear darker than the steel structure of the telescope.

Software servers have now mostly been integrated to the web interface. We have been testing these and other software changes, all in an attempt to keep ourself busy until the sky clears.

LBTI's November run was mostly weathered out, and our December run was completely lost to a series of snow storms. Something has to be done!

We must mobilize if we are to get any clear time. First, some sleep.

Josh Eisner and Peter Tuthill joined us last night. We intended to try out nonredundant aperture masking, but the skies did not cooperate. However, we made some progress on testing out the technique.

The approach masks off the telescope into discrete small apertures, and measures the visibility amplitude and phase for each pair of apertures. Peter has pioneered this approach on various telescopes, and Josh has been leading the effort here. We view this as an attractive "first light" mode for LBTI. It can work indpendently of the AO and will create images which utilize the full 22.6 m baseline of the interferometer.

The images below are those only an interferometrist could love. It shows the apertures inside LMIRCam and the power spectra (visibilities) that Peter derived from looking at an artificial source through these masks. They are exploring several mask designs, of which two are shown. The second image shows the PSF's he started from. The PSF had a significant defocus, which makes the single pinhole look like a binary. However, the power spectra appear to be measurable even for this case.

The next step is to get it working on the sky.

We had 9 inches of snow last night. This afternoon we climbed to the roof to survey the situation.

The roof has been heated since this morning, and its helping, but there is still ice all over the place.