DICKE’S SUPERRADIANCE IN ASTROPHYSICS. II. THE OH 1612 MHz LINE

Journal Article · Thu Sep 01 04:00:00 EDT 2016 · Astrophysical Journal

DOI:https://doi.org/10.3847/0004-637X/828/1/57· OSTI ID:22667458

Rajabi, Fereshteh; Houde, Martin ^[1]

---

1. Department of Physics and Astronomy, The University of Western Ontario, London, ON, N6A 3K7 (Canada)

We apply the concept of superradiance that was introduced by Dicke in 1954 to the OH molecule 1612 MHz spectral line, which is often used for the detection of masers in the circumstellar envelopes of evolved stars. Because the detection of 1612 MHz OH masers in the outer shells of envelopes of these stars implies the existence of a population inversion and a high level of velocity coherence, and that these are two necessary requirements for superradiance, we investigate whether superradiance can also happen in these regions. Superradiance is characterized by high-intensity, spatially compact, burst-like features taking place over timescales on the order of seconds to years, depending on the size and physical conditions present in the regions harboring such sources of radiation. Our analysis suggests that superradiance provides a valid explanation for previous observations of intensity flares detected in that spectral line for the U Orionis Mira star and the IRAS 18276-1431 preplanetary nebula.

• OSTI ID: 22667458
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 828; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ASTROPHYSICS
COMPACTS
DETECTION
MASERS
MHZ RANGE
MOLECULES
POPULATION INVERSION
STARS
SUPERRADIANCE
VELOCITY