2011/03/31 by R. G. Arendt, J. V. George, J. G. Staguhn +17
Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Bolometer #Crab Nebula #Flattening #Millimeter #Nebula #Radio Astronomy Observations and Technology #Spectral index #Spectral resolution #Submillimeter Array #Supernova remnant #Synchrotron #astro-ph.GA
paper · pdf · doi:10.1088/0004-637x/734/1/54
Accepted for publication in the ApJ
arxiv created 2011/03/31 · openalex publication_date 2011/05/24 · arxiv updated 2015/05/27 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
We present results of 2 mm observations of the Crab Nebula, obtained using the Goddard-IRAM Superconducting 2 Millimeter Observer (GISMO) bolometer camera on the IRAM 30 m telescope. Additional 3.3 mm observations with the MUSTANG bolometer array on the Green Bank Telescope are also presented. The integrated 2 mm flux density of the Crab Nebula provides no evidence for the emergence of a second synchrotron component that has been proposed. It is consistent with the radio power-law spectrum, extrapolated up to a break frequency of log (ν b [GHz]) = 2.84 ± 0.29 or ν b = 695 +651 − 336 GHz. The Crab Nebula is well resolved by the ∼16 7 beam (FWHM) of GISMO. Comparison to radio data at comparable spatial resolution enables us to confirm significant spatial variation of the spectral index between 21 cm and 2 mm. The main effect is a spectral flattening in the inner region of the Crab Nebula, correlated with the toroidal structure at the center of the nebula that is prominent in the near-IR through X-ray regime.