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تسجيل مستخدم جديدConfirming interstellar C$_{60}^+$ using the Hubble Space Telescope
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Recent advances in laboratory spectroscopy lead to the claim of ionized Buckminsterfullerene (C60+) as the carrier of two diffuse interstellar bands (DIBs) in the near-infrared. However, irrefutable identification of interstellar C60+ requires a match between the wavelengths and the expected strengths of all absorption features detectable in the laboratory and in space. Here we present Hubble Space Telescope (HST) spectra of the region covering the C60+ 9348, 9365, 9428 and 9577 {AA} absorption bands toward seven heavily-reddened stars. We focus in particular on searching for the weaker laboratory C60+ bands, the very presence of which has been a matter for recent debate. Using the novel STIS-scanning technique to obtain ultra-high signal-to-noise spectra without contamination from telluric absorption that afflicted previous ground-based observations, we obtained reliable detections of the (weak) 9365, 9428 {AA} and (strong) 9577 {AA} C60+ bands. The band wavelengths and strength ratios are sufficiently similar to those determined in the latest laboratory experiments that we consider this the first robust identification of the 9428 {AA} band, and a conclusive confirmation of interstellar C60+.
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The laboratory gas phase spectrum recently published by Campbell et al. has reinvigorated attempts to confirm the presence of the C$_{60}^+$ cation in the interstellar medium, thorough an analysis of the spectra of hot, reddened stars. This search is
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In 2015, Campbell et al. (Nature 523, 322) presented spectroscopic laboratory gas phase data for the fullerene cation, C$_{60}^+$, that coincide with reported astronomical spectra of two diffuse interstellar band (DIB) features at 9633 and 9578 AA. I
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