About

What is Gammapy?

Gammapy is an open-source Python package for gamma-ray analysis built on Numpy and Astropy.

It is used as core library for the Science Analysis Tool of Cherenkov Telescope Array Observatory (CTAO), and can be used to analyse data from existing gamma-ray telescopes.

Gammapy is a community-developed, open-source Python package for gamma-ray astronomy. It is an in-development affiliated package of Astropy that builds on the core scientific Python stack to provide tools to simulate and analyse the gamma-ray sky for telescopes such as CTAO, H.E.S.S., VERITAS, MAGIC, HAWC, SWGO and Fermi-LAT. Gammapy is a place for Python-coding gamma-ray astronomers to share their code and collaborate. Feature requests and contributions welcome!

Likelihood fitting of the morphology and spectra of gamma-ray sources (using iMinuit or UltraNest), multi-mission joint likelihood analysis, and physical SED modeling (e.g. Naima, GAMERA, AgnPy, JetSet), as well as the simulation of complex source models observed by different instruments, are among the key features currently available in Gammapy. In this context, Gammapy has many features on much broader scope: it also includes functionalities for data handling, background modeling, source detection, easy access to commonly used datasets and catalogs, statistical methods, EBL convolution, Dark Matter models, and even the simulation of Galactic source populations.

We are continuously expanding Gammapy's features with new analysis algorithms and enabling multi-wavelength and multi-messenger analyses. In parallel, we are working on the FAIRification of Gammapy to ensure that all Gammapy products are reusable and interoperable.

When using Gammapy for your publication, please follow the citation scheme presented in the acknowledgment page in order to support the Gammapy team.

Publications

A&A, 678, A157 (2023) - “Gammapy: A Python package for gamma-ray astronomy”
A&A, 632, A72 (2019) - “Validation of open-source science tools and background model construction in γ-ray astronomy”
A&A, 625, A10 (2019) - “Towards open and reproducible multi-instrument analysis in gamma-ray astronomy”
2017ICRC...35..766D - “Gammapy - A prototype for the CTA science tools”
2015ICRC…34..789D - “Gammapy: An open-source Python package for gamma-ray astronomy”

The full list of publications using Gammapy can be found with this link.

Awards and Prizes

Feb. 2022: Jury Prize of the Open Science Awards Ceremony during the Paris Open Science European Conference - OSEC Press Release
July 2021: Prize of the best poster for A. Donath during the 37th ICRC - ICRC announcement
June 2021: Adoption of Gammapy as Science Analysis Tool package by the CTAO - CTAO Press Release

Acknowledgements

We would like to thank the Astropy, Numpy, Scipy, IPython, Jupyter and Matplotlib communities for providing their packages which are invaluable to the development of Gammapy. We thank the GitHub team for providing us with an excellent free development platform. Thanks to JetBrains making PyCharm freely available for Gammapy development.

We would like to deeply thank all the Gammapy developers, experts and also users that have provided feedback and submitted bug reports. And we warmly thank all group leaders of the supporting institutes.

We thank also the funding support from various entities:

the Spanish Ministry of Science and Innovation and the Spanish Research State Agency (AEI) under grant PID2019-104114RB-C33/AEI/10.13039/501100011034,
the Institute of Cosmos Sciences University of Barcelona (ICCUB, Unidad de Excelencia “María de Maeztu”) through grant CEX2019-000918-M.
the French research ministry founding CTAO as Très Grande Infrastructure de Recherche,
the ESCAPE H2020 project, GA No 824064,
the Agence Nationale de la Recherche (ANR-17-CE31-0014, PECORA),
the German BMBF (ErUM) and DFG (SFBs 876 and 1491),
the Ramon y Cajal program through grant RYC-2020-028639-I,
the grant CEX2021-001131-S funded by MCIN/AEI/ 10.13039/501100011033,
the Spanish Ministerio de Ciencia e Innovacion (MICINN), the European Union - NextGenerationEU and PRTR through the programme Juan de la Cierva (grant FJC2020-046063-I), by the MICINN (grant PID2019-107847RB-C41), and from the CERCA program of the Generalitat de Catalunya,
the NASA contract NAS8-03060 (Chandra X-ray Center),
the Spanish Ministry of Universities through the Maria Zambrano Talent Attraction Programme, 2021–2023,
the Observatoire de Paris for its numerous grants through the Action Fédératrice CTA and the Action Pluri-annauelle Initiatrice "Astrophysique des hautes énergies",
the ASTERICS H2020 project (Astronomy ESFRI & Research Infrastructure Cluster), GA No 653477,
the Spanish MINECO/AEI projects: FPA2015-69210-C6-3-R, FPA2017-82729-C6-3-R, AYA2016-8089-P.

A special acknowledgment has to be given to our first lead developer, Christoph Deil, who started the Gammapy project and paved the way for its future success.

Communities

Gammapy team members are inserted into different communities, within research and experimental collaborations, and within Open Science alliances. They participate in the establishment of standards, best practice recommendations, data models, data formats, algorithms, etc.

The following table lists the communities in which we are inserted:

Open Science	Experiments
ESCAPE	CTAO
EVERSE	Fermi-LAT
GADF	H.E.S.S.
IVOA	MAGIC
NumFOCUS	SWGO
OSCARS	VERITAS
Research Data Alliance
SoftWare Heritage
VODF

Donate

Gammapy will always be 100% open source software, free for all to use and released under the liberal terms of the modified BSD license. We have a large number of contributors who volunteer their time to improve Gammapy, and some institutions give resources for the building of the CTAO Science Analysis Tool. So, financial resources are needed to run the project and accelerate its development (e.g. compliance with the FAIR4RS principles, the VO compliance, the multi-wavelength and multi-messenger features, parallelism, performance, etc). If you have found Gammapy useful in your work, research, please consider making a donation to the project commensurate with your resources. Any amount helps!

Donations are managed by the NumFOCUS foundation, which passes your contribution to the Gammapy project, and provides the Gammapy development team with basic administrative and legal services. NumFOCUS is a 501(c)3 non-profit foundation, so if you are subject to the US Tax law, your contributions are tax-deductible.