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

We report on Atacama Large Millimeter/submillimeter Array (ALMA) detectionsof molecular absorption lines in Bands 3, 6 and 7 toward four radio-loudquasars, which were observed as the bandpass and complex gain calibrators. Theabsorption systems, three of which are newly detected, are found to be Galacticorigin. Moreover, HCO absorption lines toward two objects are detected, whichalmost doubles the number of HCO absorption samples in the Galactic diffusemedium. In addition, high HCO to H13CO+ column density ratios are found,suggesting that the interstellar media (ISM) observed toward the twocalibrators are in photodissociation regions, which observationally illustratesthe chemistry of diffuse ISM driven by ultraviolet (UV) radiation. Theseresults demonstrate that calibrators in the ALMA Archive are potential sourcesfor the quest for new absorption systems and for detailed investigation of thenature of the ISM.

New Detections of Galactic Molecular Absorption Systems toward ALMA Calibrator Sources