Significance in Gamma Ray Astronomy with Systematic Errors

Abstract

The influence of systematic errors on the calculation of the statistical significance of a $\gamma$-ray signal with the frequently invoked Li and Ma method is investigated. A simple criterion is derived to decide whether the Li and Ma method can be applied in the presence of systematic errors. An alternative method is discussed for cases where systematic errors are too large for the application of the original Li and Ma method. This alternative method reduces to the Li and Ma method when systematic errors are negligible. Finally, it is shown that the consideration of systematic errors will be important in many analyses of data from the planned Cherenkov Telescope Array.

Accepted for publication in Astroparticle Physics

References in corpus (16)

• Design Concepts for the Cherenkov Telescope Array
• Observations of the Crab Nebula with H.E.S.S
• Background Modelling in Very-High-Energy gamma-ray Astronomy
• TeV Gamma-Ray Sources from a Survey of the Galactic Plane with Milagro
• Search for a Dark Matter annihilation signal from the Galactic Center halo with H.E.S.S
• Performance of the MAGIC stereo system obtained with Crab Nebula data
• Monte Carlo design studies for the Cherenkov Telescope Array
• H.E.S.S. observations of the supernova remnant RX J0852.0-4622: shell-type morphology and spectrum of a widely extended VHE gamma-ray source
• HESS Observations and VLT Spectroscopy of PG 1553+113
• Observation of TeV Gamma Rays from the Crab Nebula with Milagro Using a New Background Rejection Technique
• VERITAS Observations of a Very High Energy Gamma-ray Flare from the Blazar 3C 66A
• Anisotropy studies around the galactic centre at EeV energies with the Auger Observatory
• Statistical Issues in Astrophysical Searches for Particle Dark Matter
• Limits, discovery and cut optimization for a Poisson process with uncertainty in background and signal efficiency: TRolke 2.0
• A generalized likelihood ratio test statistic for Cherenkov telescope data
• Handling Systematic Uncertainties and Combined Source Analyses for Atmospheric Cherenkov Telescopes

Cited by in corpus (7)

• The population of TeV pulsar wind nebulae in the H.E.S.S. Galactic Plane Survey
• WIMP searches with gamma rays in the Fermi era: challenges, methods and results
• VERITAS Observations of the Galactic Center Region at Multi-TeV Gamma-Ray Energies
• Significance of an excess in a counting experiment: assessing the impact of systematic uncertainties and the case with Gaussian background
• Statistical Tools for Imaging Atmospheric Cherenkov Telescopes
• The Making of Catalogues of Very-High-Energy γ-ray Sources
• Extending the Li&Ma method to include PSF information