Identifying the Radio Bubble Nature of the Microwave Haze

Abstract

Using 7-year data from the Wilkinson Microwave Anisotropy Probe I identify a sharp "edge" in the microwave haze at high Galactic latitude (35 deg < |b| < 55 deg) that is spatially coincident with the edge of the "Fermi Haze/Bubbles". This finding proves conclusively that the edge in the gamma-rays is real (and not a processing artifact), demonstrates explicitly that the microwave haze and the gamma-ray bubbles are indeed the same structure observed at multiple wavelengths, and strongly supports the interpretation of the microwave haze as a separate component of Galactic synchrotron (likely generated by a transient event) as opposed to a simple variation of the spectral index of disk synchrotron. In addition, combining these data sets allows for the first determination of the magnetic field within a radio bubble using microwaves and gamma-rays by taking advantage of the fact that the inverse Compton gamma-rays are primarily generated by scattering of CMB photons at these latitudes, thus minimizing uncertainty in the target radiation field. Assuming uniform volume emissivity, I find that the magnetic field within our Galactic microwave/gamma-ray bubbles is ~5 muG above 6 kpc off of the Galactic plane.

6 pages, 5 figures; submitted to ApJL

References in corpus (5)

• Giant Gamma-ray Bubbles from Fermi-LAT: AGN Activity or Bipolar Galactic Wind?
• The Fermi Bubbles: Giant, Multi-Billion-Year-Old Reservoirs of Galactic Center Cosmic Rays
• Inverse Compton Origin of the Hard X-Ray and Soft Gamma-Ray Emission from the Galactic Ridge
• Extended Anomalous Foreground Emission in the WMAP 3-Year Data
• Constraining Spinning Dust Parameters with the WMAP Five-Year Data

Cited by in corpus (19)

• A Unified Model of the Fermi Bubbles, Microwave Haze, and Polarized Radio Lobes: Reverse Shocks in the Galactic Center's Giant Outflows
• The Fermi Bubbles as Starburst Wind Termination Shocks
• The Fermi Bubbles: Gamma-ray, Microwave, and Polarization Signatures of Leptonic AGN Jets
• Planck Intermediate Results. IX. Detection of the Galactic haze with Planck
• A Hadronic-Leptonic Model for the Fermi Bubbles: Cosmic-Rays in the Galactic Halo and Radio Emission
• Planck intermediate results. XXIII. Galactic plane emission components derived from Planck with ancillary data
• Multi-wavelength Emission from the Fermi Bubble I. Stochastic acceleration from Background Plasma
• Fermi bubble edges: spectrum and diffusion function
• A Latitude-Dependent Analysis of the Leptonic Hypothesis for the Fermi Bubbles
• Dark matter implications of the WMAP-Planck Haze
• Fermi bubbles: high latitude X-ray supersonic shell
• Unveiling the Fermi Bubbles origin with MeV photon telescopes
• The spectral index of polarized diffuse Galactic emission between 30 and 44 GHz
• Fermi bubbles: the collimated outburst needed to explain forward-shock edges
• A Perturbative Analysis of Synchrotron Spectral Index Variation over Microwave Sky
• Testing the dark matter origin of the WMAP-Planck Haze with radio observations of Spiral Galaxies
• Possible counterpart signal of the Fermi bubbles at the cosmic-ray positrons
• Fermi-bubble bulk and edge analysis reveals dust, cooling breaks, and cosmic-ray diffusion, facilitating a self-consistent model
• Detection of polarized Fermi-bubble synchrotron and dust emission