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At the Whipple Observatory on Mount Hopkins in Arizona, we have installed and successfully operated a prototype astro-comb wavelength calibrator, based on a Ti:sapphire laser frequency comb, for the TRES high-resolution astrophysical spectrograph.  We are currently developing an astro-comb operating in the green part of the spectrum, to be integrated with the HARPS-North spectrograph in the Canary Islands.  The accuracy of astrophysical spectroscopy, e.g., to detect small, Earth-like exoplanets, will be improved by more than an order of magnitude by such astro-comb wavelength calibrators.
 
In our labs at the Harvard Center for Brain Science, we are developing and applying powerful new imaging tools for brain science -- including functionalized electron microscopy using multi-color cathodoluminescence to determine both the structure and function of brain circuits with individual synapse resolution. This image illustrates the fluorescence of ~10 micron natural diamond grit under 350 nm UV excitation.
 
The open-access, low-field MRI system is located at the Martinos Center for Biomedical Imaging at Massachusetts General Hospital and focuses on spin-polarized materials and their use as magnetic tracers in vivo.
 
Confocal image demonstrating uptake of fluorescent nanodiamonds containing nitrogen-vacancy color centers by live human embryonic kidney (HEK) cells in culture. These nanodiamonds do not bleach under extended optical illumination, unlike organic fluorophores.
 
Ron Walsworth and Chih-Hao Li are shown adjusting a Ti:sapphire laser frequency comb, which can be used to improve the accuracy and stability of wavelength calibration of astrophysical spectrographs by up to two orders of magnitude. This astro-comb will provide a key advance in the resolution of changes in astrophysical Doppler shifts and redshifts, and thus may allow the discovery of Earth-like planets and new measurements of astrophysical dynamics relevant to cosmology.