Gamma ray bursts and the origin of galactic positrons
arXiv:astro-ph/0405005 · doi:10.1016/j.physletb.2006.03.022
Abstract
A recent observation of the 511 keV electron-positron annihilation line from the Galactic bulge has prompted a debate on the origin of the galactic positrons responsible for this emission. Assuming equilibrium between annihilation and injection of positrons in the Galaxy, we investigate the possibility that positrons were produced by past gamma ray bursts (GRBs). We compare the positron annihilation rate inferred from the observed 511 keV line with the predicted injection rate due to electron-positron pairs leaking out of individual GRBs and those pairs produced by GRB photons in the dense molecular clouds at the Galactic center. We conclude that the proposed scenario is marginally consistent with observations, and can reproduce the observed normalization of the annihilation line only for higher-than-average values of the GRB rate in the Galaxy and/or the molecular clouds optical depth for pair production.
12 pages; substantial changes; to appear in Phys. Lett. B
References in corpus (21)
- Big Bang Nucleosynthesis (in "The Review of Particle Properties" 2004)
- Gamma-Ray Bursts: Progress, Problems & Prospects
- The all-sky distribution of 511 keV electron-positron annihilation emission
- Stringent Constraint on Galactic Positron Production
- Gamma-Ray Constraint on Galactic Positron Production by MeV Dark Matter
- Light Neutralino Dark Matter in the NMSSM
- Positron annihilation spectrum from the Galactic Center region observed by SPI/INTEGRAL
- Possible Evidence For Axino Dark Matter In The Galactic Bulge
- Unstable Relics as a Source of Galactic Positrons
- 511 KeV Photons From Color Superconducting Dark Matter
- INTEGRAL/SPI Limits on Electron-Positron Annihilation Radiation from the Galactic Plane
- Supernova explosions, 511 keV photons, gamma ray bursts and mirror matter
- Could electron-positron annihilation lines in the Galactic center result from pulsar winds?
- 511 keV line from Q balls in the Galactic Center
- GRBs and the 511 keV emission of the Galactic bulge
- 511 KeV photons from superconducting cosmic strings
- 511 keV Gamma Ray from Moduli Decay in the Galactic Bulge
- The Observed Galactic Annihilation Line. Possible Signature of the Cluster for Accreting Small Mass Black Holes
- Primordial Black Holes, Hawking Radiation and the Early Universe
- Galactic Center Molecular Clouds
- Search for a light dark matter annihilation signal in the Sagittarius Dwarf Galaxy
Cited by in corpus (33)
- The 511 keV emission from positron annihilation in the Galaxy
- Stringent Constraint on Galactic Positron Production
- Dark Matter Candidates: A Ten-Point Test
- A Natural Supersymmetric Model with MeV Dark Matter
- Wild at Heart:-The Particle Astrophysics of the Galactic Centre
- Constraints on Light Dark Matter From Core-Collapse Supernovae
- Continuum gamma-ray emission from light dark matter positrons and electrons
- Galactic 511 keV line from MeV millicharged dark matter
- Role of Galactic sources and magnetic fields in forming the observed energy-dependent composition of ultrahigh-energy cosmic rays
- TASI 2008 Lectures on Dark Matter
- Shedding Light on Dark Matter: A Faraday Rotation Experiment to Limit a Dark Magnetic Moment
- Signals from dark atom formation in halos
- Metastable dark matter mechanisms for INTEGRAL 511 keV rays and DAMA/CoGeNT events
- The 511 keV Excess and Primordial Black Holes
- Soft gamma-ray background and light Dark Matter annihilation
- A Comprehensive Search for Gamma-Ray Lines in the First Year of Data from the INTEGRAL Spectrometer
- Positrons and 511 keV radiation as tracers of recent binary neutron star mergers
- On the Origin of the 511 keV Emission in the Galactic Centre
- Exciting dark matter in the galactic center
- MeV Right-handed Neutrinos and Dark Matter
- Dark matter and Colliders searches in the MSSM
- Spectroscopy of a canonically quantized horizon
- The Sensitivity of Future Gamma-Ray Telescopes to Primordial Black Holes
- Can past gamma-ray bursts explain both INTEGRAL and ATIC/PAMELA/Fermi anomalies simultaneously?
- Abelian dark matter models for 511 keV gamma rays and direct detection
- Dark Matter: the Connection with Gamma-Ray Astrophysics
- Light superconducting strings in the Galaxy
- An Experiment to Search for Light Dark Matter in Low-Energy ep Scattering
- Ultrahigh-energy nuclei, photons, and magnetic fields
- Positron Annihilations at the Galactic Center: Generating More Questions Than Answers
- Primordial black holes in Randall-Sundrum: Cosmological signatures
- Cosmic connections: from cosmic rays to gamma rays, to cosmic backgrounds and magnetic fields
- Galactic Electron-Positron Annihilation Emission from X-Ray Binaries with Transient and Persistent Jets