Wild at Heart: the particle astrophysics of the Galactic Centre

摘要: We consider the high-energy astrophysics of inner ∼200 pc Galaxy. Our modelling this region shows that supernovae exploding here every few thousand years inject enough power to (i) sustain steady-state, in situ population cosmic rays (CRs) required generate region's non-thermal radio and TeV γ-ray emission; (ii) drive a powerful wind advects particles out Galactic Centre; (iii) supply low-energy CRs whose Coulombic collisions temperature ionization rate anomalously warm envelope H 2 detected throughout Central Molecular Zone; (iv) accelerate primary electrons which provide extended, emission seen over ∼150 scales above below plane (the Centre lobe); (v) protons heavier ions which, advected very large (up ∼ 10 kpc), recently identified Wilkinson Microwave Anisotropy Probe (WMAP) haze corresponding Fermi haze/bubbles. bounds average magnetic field amplitude degrees Galaxy range 60 < B/μG 400 (at 2σ confidence) even likely do not have time penetrate into cores dense molecular clouds before removes them from region. This latter finding apparently disfavours scenarios - starburst-like environment act substantially modify conditions star formation. speculate we identify plays crucial role advecting positrons nucleus bulge, thereby explaining extended morphology 511 keV line emission. present extensive appendices reviewing environmental Centre, deriving formation supernova rates there, setting prior evidence exists, supporting notion fast outflow