We report on a variety of standard techniques used by New Horizons includinga solar ultraviolet occultation, ultraviolet airglow observations, andhigh-phase look-back particulate search imaging to search for an atmospherearound Pluto's large moon Charon during its flyby in July 2015. Analyzing thesedatasets, no evidence for a present day atmosphere has been found for 14potential atomic and molecular species, all of which are now constrained tohave pressures below 0.3 nanobar, as we describe below, these are much morestringent upper limits than the previously available 15-110 nanobar constraints(e.g., Sicardy et al. 2006); for example, we find a 3$\sigma$ upper limit foran N$_2$ atmosphere on Charon is 4.2 picobars and a 3$\sigma$ upper limit forthe brightness of any atmospheric haze on Charon of I/F=2.6x10$^{-5}$. A radiooccultation search for an atmosphere around Charon was also conducted by NewHorizons but will be published separately by other authors.
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