Contact Info

Physicist
Lawrence Livermore National Laboratory

Tel:  (925) 422-2102
Fax:  (925) 422-1796

ammons1 [at] llnl [dot] gov

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Finding the Most Massive Cosmic Telescopes

Through gravitational lensing, massive galaxy clusters can magnify more distant background galaxies into detectability.  Finding the most massive galaxy clusters providing the most optimal field of high magnification is a critical goal for future high-redshift galaxy searches.  But can the best fields for this purpose be chance alignments of clusters at different redshifts, rather than single clusters?  Using Luminous Red Galaxies (LRG) as a proxy for unseen mass, we have selected a catalog of multiple-cluster beams providing extended fields of high magnification ideal for magnifying distant sources into detectability.

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Adaptive Optics Instrumentation

I research adaptive optics (AO) techniques for large telescopes, including tomographic adaptive optics.  I have used a scaled-down testbed simulator of a high-order tomographic AO system to obtain good visible-light image quality (Strehl = 20%) on a simulated 10-meter telescope, using a tomographic architecture with multiple laser guide stars.  

Our team has installed a visible light AO system on the 1-meter Nickel telescope at Lick Observatory to prove several enabling technologies on-sky, including (1) MEMS deformable mirror operation, (2) open-loop operation of wavefront sensors, and (3) use of uplink LGS correction to lower total required laser power.

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