Upper Limits for Emissions in the Coma of Comet 67P/Churyumov-Gerasimenko Near Perihelion as Measured by Rosetta's Alice Far-Ultraviolet Spectrograph

Abstract

The Alice far-UV imaging spectrograph (700-2050 A) acquired over 70,000 spectral images during Rosetta's 2-year escort mission, including over 20,000 in the months surrounding perihelion when the comet activity level was highest. We have developed automated software to fit and remove ubiquitous H, O, C, S, and CO emissions from Alice spectra, along with reflected solar continuum and absorption from gaseous H2O in the comet's coma, which we apply to a "grand sum" of integrations taken near perihelion. We present upper limits on the presence of one ion and 17 neutral atomic species for this time period. These limits are compared to results obtained by other Rosetta instruments where possible, as well as to CI carbonaceous chondrites and solar photospheric abundances.

arXiv comment9 pages, 3 figures; Astronomical Journal, in press

References in corpus (17)

• The chemical composition of the Sun
• Abundances of the elements in the solar system
• Measurements of the Near-Nucleus Coma of Comet 67P/Churyumov-Gerasimenko with the Alice Far-Ultraviolet Spectrograph on Rosetta
• Evolution of CO${}_2$, CH${}_4$, and OCS abundances relative to H${}_2$O in the coma of comet 67P around perihelion from Rosetta/VIRTIS-H observations
• Alice: The Rosetta Ultraviolet Imaging Spectrograph
• The birth and growth of a solar wind cavity around a comet -- Rosetta observations
• Krypton isotopes and noble gas abundances in the coma of comet 67P/Churyumov-Gerasimenko
• Surface localization of gas sources on comet 67P/Churyumov-Gerasimenko based on DFMS/COPS data
• The Fourth Positive System of Carbon Monoxide in the Hubble Space Telescope Spectra of Comets
• Atomic Data Revisions for Transitions Relevant to Observations of Interstellar, Circumgalactic, and Intergalactic Matter
• The Nature and Frequency of the Gas Outbursts in Comet 67P/Churyumov-Gerasimenko observed by the Alice Far-ultraviolet Spectrograph on Rosetta
• Evidence for depletion of heavy silicon isotopes at comet 67P/Churyumov-Gerasimenko
• H${}_2$O and O${}_2$ Absorption in the Coma of Comet 67P/Churyumov-Gerasimenko Measured by the Alice Far-Ultraviolet Spectrograph on Rosetta
• FUV Spectral Signatures of Molecules and the Evolution of the Gaseous Coma of Comet 67P/Churyumov-Gerasimenko
• Ultraviolet Observations of Coronal Mass Ejection Impact on Comet 67P/Churyumov-Gerasimenko by Rosetta Alice
• Stellar Occultation by Comet 67P/Churyumov-Gerasimenko Observed with Rosetta's Alice Far-Ultraviolet Spectrograph
• Rosetta Alice Ultraviolet Spectrograph Flight Operations and Lessons Learned