English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The first identification of the argonium ion (ArH+) towards the Crab Nebulasupernova remnant was proclaimed by the Herschel in the sub-millimeter andfar-infrared domain. Very recently the discovery of the hydro-helium cation(HeH+) in the planetary nebula (NGC 7027) has been reported by using the SOFIA.The elemental abundance of neon is much higher than that of the argon. However,the presence of neonium ions (NeH+) is yet to be confirmed in space. Though thehydroxyl radicals (OH) are very abundant either in neutral or in the cationicform, hydroxyl cations of such noble gases (i.e., ArOH+, NeOH+, and HeOH+) areyet to be identified in space. Here, we employ a spectral synthesis code toexamine the chemical evolution of the hydride and hydroxyl cations of thevarious isotopes of Ar, Ne, and He in the Crab Nebula filament and calculatetheir line emissivity and intrinsic line surface brightness. We successfullyexplain the observed surface brightness of two transitions of ArH+ (617 and1234 GHz), one transition of OH+ (971 GHz), and one transition of H2 (2.12micrometer). We also explain the observed surface brightness ratios betweenvarious molecular and atomic transitions. We find that our model reproduces theoverall observed features when a hydrogen number density of ~10^4-10^6 cm^-3and a cosmic-ray ionization rate per H2 of ~10^-11-10^-10 s^-1 are chosen. Wediscuss the possibility of detecting some hydride and hydroxyl cations in theCrab and diffuse cloud environment. Some transitions of these molecules arehighlighted for future astronomical detection.

Exploring the Possibility of Identifying Hydride and Hydroxyl Cations of Noble Gas Species in the Crab Nebula Filament