Towards open and reproducible multi-instrument analysis in gamma-ray astronomy

Abstract

The analysis and combination of data from different gamma-ray instruments involves the use of collaboration proprietary software and case-bycase methods. The effort of defining a common data format for high-level data, namely event lists and instrument response functions (IRFs), has recently started for very-high-energy gamma-ray instruments, driven by the upcoming Cherenkov Telescope Array (CTA). In this work we implemented this prototypical data format for a small set of MAGIC, VERITAS, FACT, and H.E.S.S. Crab nebula observations, and we analyzed them with the open-source gammapy software package. By combining data from Fermi-LAT, and from four of the currently operating imaging atmospheric Cherenkov telescopes, we produced a joint maximum likelihood fit of the Crab nebula spectrum. Aspects of the statistical errors and the evaluation of systematic uncertainty are also commented upon, along with the release format of spectral measurements. The results presented in this work are obtained using open-access on-line assets that allow for a long-term reproducibility of the results.

Towards Multi-Instrument and ReproducibleGamma-Ray Analysis

“…This will allow any user to reproduce the results in an interactive environment. For more details we refer the reader to our full paper [1] and to our online repository https://github.com/open-gamma-ray-astro/joint-crab…”

“…The resulting spectral energy distributions are shown in figure 2, together with a theoretical model taken from [13]. For a full table of results we refer to our paper [1].…”

“…This proceeding summarizes the most important results of our previously published paper entitled Towards open and reproducible multi-instrument analysis in gamma-ray astronomy [1]. Combining images from multiple astronomical facilities is key to unravel some of the mysteries of modern astrophysics.…”

Toward a Public MAGIC Gamma-Ray Telescope Legacy Data Portal

“…It is then clear that besides an event list (time energy direction) ancillary information must be annexed to enable scientists from within and outside the community to reproduce scientific results with MAGIC data. As an intermediate step to releasing the full event list, an activity that is ongoing within MAGIC [4], DL3 MAGIC data were produced for the project in Ref. [4].…”

“…As an intermediate step to releasing the full event list, an activity that is ongoing within MAGIC [4], DL3 MAGIC data were produced for the project in Ref. [4]. MAGIC can share high level products from publications, these comprise e.g.…”