Vol 21, No 10 (2021) / Cui

The low cosmic-ray density in the Polaris Flare

Zhi-Wei Cui, Rui-Zhi Yang, Bing Liu

Abstract

We reported the γ-ray observation towards the giant molecular cloud Polaris Flare. Together with the dust column density map, we derived the cosmic ray (CR) density and spectrum in this cloud. Compared with the CR measured locally, the CR density in the Polaris Flare is significantly lower and the spectrum is softer. Such a different CR spectrum reveals either a rather large gradient of CR distribution in the direction perpendicular to the Galactic plane or a suppression of CR inside molecular clouds.

Keywords


gamma rays: ISM, (ISM:) cosmic rays, ISM: clouds

Full Text:

PDF


DOI: https://doi.org/10.1088/1674-4527/21/10/246

Refbacks

  • There are currently no refbacks.