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2017

Selected Works

Life Sciences

Articles 1 - 3 of 3

Full-Text Articles in Physics

Beyond 3 Au From The Sun: The Hypervolatiles Ch4, C2h6, And Co In The Distant Comet C/2006 W3 (Christensen), Boncho P. Bonev, Geronimo L. Villanueva, Michael A. Disanti, Hermann Boehnhardt, Manuela Lippi, Erika L. Gibb, Lucas Paganini, Michael J. Mumma May 2017

Beyond 3 Au From The Sun: The Hypervolatiles Ch4, C2h6, And Co In The Distant Comet C/2006 W3 (Christensen), Boncho P. Bonev, Geronimo L. Villanueva, Michael A. Disanti, Hermann Boehnhardt, Manuela Lippi, Erika L. Gibb, Lucas Paganini, Michael J. Mumma

Erika Gibb

Comet C/2006 W3 (Christensen) remained outside a heliocentric distance (R h) of 3.1 au throughout its apparition, but it presented an exceptional opportunity to directly sense a suite of molecules released from its nucleus. The Cryogenic Infrared Echelle Spectrograph at ESO-VLT detected infrared emissions from the three "hypervolatiles" (CO, CH4, and C2H6) that have the lowest sublimation temperatures among species that are commonly studied in comets by remote sensing. Even at R h = 3.25 au, the production rate of each molecule exceeded those measured for the same species in a number of other comets, although these comets were observed …


The Composition Of Comet C/2012 K1 (Panstarrs) And The Distribution Of Primary Volatile Abundances Among Comets, Nathan X. Roth, Erika L. Gibb, Boncho P. Bonev, Michael A. Disanti, Michael J. Mumma, Geronimo L. Villanueva, Lucas Paganini Mar 2017

The Composition Of Comet C/2012 K1 (Panstarrs) And The Distribution Of Primary Volatile Abundances Among Comets, Nathan X. Roth, Erika L. Gibb, Boncho P. Bonev, Michael A. Disanti, Michael J. Mumma, Geronimo L. Villanueva, Lucas Paganini

Erika Gibb

On 2014 May 22 and 24 we characterized the volatile composition of the dynamically new Oort cloud comet C/2012 K1 (PanSTARRS) using the long-slit, high resolution (λ/Δλ ≈ 25,000) near-infrared echelle spectrograph (NIRSPEC) at the 10 m Keck II telescope on Maunakea, Hawaii. We detected fluorescent emission from six primary volatiles (H2O, HCN, CH4, C2H6, CH3OH, and CO). Upper limits were derived for C2H2, NH3, and H2CO. We report rotational temperatures, production rates, and mixing ratios (relative to water). Compared with median abundance ratios for primary volatiles in other sampled Oort cloud comets, trace gas abundance ratios in C/2012 K1 …


A Sonic Net Excludes Birds From An Airfield: Implications For Reducing Bird Strike And Crop Losses, John P. Swaddle, Dana L. Moseley, Mark H. Hinders, Elizabeth P. Smith Feb 2017

A Sonic Net Excludes Birds From An Airfield: Implications For Reducing Bird Strike And Crop Losses, John P. Swaddle, Dana L. Moseley, Mark H. Hinders, Elizabeth P. Smith

John Swaddle

Collisions between birds and aircraft cause billions of dollars of damages annually to civil, commercial, and military aviation. Yet technology to reduce bird strike is not generally effective, especially over longer time periods. Previous information from our lab indicated that filling an area with acoustic noise, which masks important communication channels for birds, can displace European Starlings (Sturnus vulgaris) from food sources. Here we deployed a spatially controlled noise (termed a “sonic net”), designed to overlap with the frequency range of bird vocalizations, at an airfield. By conducting point counts, we monitored the presence of birds for four weeks before …