Deciphering the Dipole Anisotropy of Galactic Cosmic Rays
Abstract
Recent measurements of the dipole anisotropy in the arrival directions of Galactic cosmic rays (CRs) indicate a strong energy dependence of the dipole amplitude and phase in the TeV-PeV range. We argue here that these observations can be well understood within standard diffusion theory as a combined effect of (i) one or more local sources at Galactic longitude 12 0 ° ≲l ≲30 0 ° dominating the CR gradient below 0.1-0.3 PeV, (ii) the presence of a strong ordered magnetic field in our local environment, (iii) the relative motion of the solar system, and (iv) the limited reconstruction capabilities of ground-based observatories. We show that an excellent candidate of the local CR source responsible for the dipole anisotropy at 1-100 TeV is the Vela supernova remnant.
- Publication:
-
Physical Review Letters
- Pub Date:
- October 2016
- DOI:
- 10.1103/PhysRevLett.117.151103
- arXiv:
- arXiv:1605.06446
- Bibcode:
- 2016PhRvL.117o1103A
- Keywords:
-
- Astrophysics - High Energy Astrophysical Phenomena;
- High Energy Physics - Experiment;
- High Energy Physics - Phenomenology
- E-Print:
- version published in Phys. Rev. Lett. 117, 151103 (2016)