IRAS 00450+7401 and the Mid-infrared Fade/Burst Cycle of R Coronae Borealis-type Stars
Artikel i vetenskaplig tidskrift, 2023

We present optical and infrared imaging and spectroscopy of the R Coronae Borealis-type (R Cor Bor) star IRAS 00450+7401. Optical spectra further confirm its classification as a cool R Cor Bor system, having a hydrogen-deficient carbon star spectral subclass of HdC5 or later. Mid-infrared spectroscopy reveals the typical ∼8 μm “hump” seen in other R Cor Bor stars and no other features. A modern-epoch spectral energy distribution shows bright emission from hot dust having T dust > 600 K. Historical infrared data reveal generally cooler dust color temperatures combined with long-term fading trends, but provide no discernible correlation between flux level and temperature. Investigating the most mid-infrared variable R Cor Bor stars found in IRAS, AKARI, and WISE data reveals similar fading trends, bursts that can show a factor of up to 10 change in flux density between epochs, and blackbody-fit dust color temperatures that span 400-1300 K. While some R Cor Bor stars such as IRAS 00450+7401 appear to undergo fade/burst cycles in the mid-infrared, significant gaps in temporal coverage prevent conclusively identifying any preferred timescale for their mid-infrared variability and circumstellar dust temperature changes.

Författare

William A. Burris

San Diego State University

C. Melis

Center for Astrophysics & Space Sciences

Allen W. Shafter

San Diego State University

Georgia Panopoulou

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik

E. L. Wright

University of California

John Della Costa

San Diego State University

Astronomical Journal

0004-6256 (ISSN) 1538-3881 (eISSN)

Vol. 166 2 40

Ämneskategorier

Astronomi, astrofysik och kosmologi

Atom- och molekylfysik och optik

Annan elektroteknik och elektronik

DOI

10.3847/1538-3881/acda93

Mer information

Senast uppdaterat

2023-07-26