Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

# High-energy particle acceleration in the shell of a supernova remnant

## Abstract

A significant fraction of the energy density of the interstellar medium is in the form of high-energy charged particles (cosmic rays)1. The origin of these particles remains uncertain. Although it is generally accepted that the only sources capable of supplying the energy required to accelerate the bulk of Galactic cosmic rays are supernova explosions, and even though the mechanism of particle acceleration in expanding supernova remnant (SNR) shocks is thought to be well understood theoretically2,3, unequivocal evidence for the production of high-energy particles in supernova shells has proven remarkably hard to find. Here we report on observations of the SNR RX J1713.7 - 3946 (G347.3 - 0.5), which was discovered by ROSAT4 in the X-ray spectrum and later claimed as a source of high-energy γ-rays5,6 of TeV energies (1 TeV = 1012 eV). We present a TeV γ-ray image of the SNR: the spatially resolved remnant has a shell morphology similar to that seen in X-rays, which demonstrates that very-high-energy particles are accelerated there. The energy spectrum indicates efficient acceleration of charged particles to energies beyond 100 TeV, consistent with current ideas of particle acceleration in young SNR shocks.

This is a preview of subscription content, access via your institution

## Relevant articles

• ### Recent Developments in Particle Acceleration at Shocks: Theory and Observations

Space Science Reviews Open Access 05 May 2022

• ### The interstellar medium in young supernova remnants: key to the production of cosmic X-rays and $\gamma$-rays

Astrophysics and Space Science Open Access 23 June 2021

• ### Brilliant petawatt gamma-ray pulse generation in quantum electrodynamic laser-plasma interaction

Scientific Reports Open Access 24 March 2017

## Access options

$32.00 All prices are NET prices. ## References 1. Longair, M. S. High Energy Astrophysics Vol. 2, Stars, the Galaxy and the Interstellar Medium 2nd edn (Cambridge Univ. Press, Cambridge, 2002) 2. Drury, L. O'C, Aharonian, F. A. & Völk, H. J. The gamma-ray visibility of supernova remnants. A test of cosmic-ray origin. Astron. Astrophys. 287, 959–971 (1994) 3. Naito, T. & Takahara, F. High-energy gamma-ray emission from supernova remnants. J. Phys. G 20, 477–486 (1994) 4. Pfeffermann, E. & Aschenbach, B. in Röntgenstrahlung from the Universe (eds Zimmermann, H. U., Truemper, J. E. & Yorke, H.) 267–268 (Report 263, MPE, Garching, 1996) 5. Muraishi, H. et al. Evidence for TeV gamma-ray emission from the shell type SNR RX J1713.7–3946. Astron. Astrophys. 354, L57–L61 (2000) 6. Enomoto, R. et al. The acceleration of cosmic-ray protons in the supernova remnant RX J1713.7–3946. Nature 416, 823–826 (2002) 7. Hinton, J. A. (H.E.S.S. Collaboration) The status of the HESS project. N. Astron. Rev. 48, 331–337 (2004) 8. Hofmann, W. (H.E.S.S. Collaboration) in Proc. 28th ICRC (Tsukuba) (eds Kajita, T., Asaoka, Y., Kawachi, A., Matsubara, Y. & Sasaki, M.) 2811–2814 (Univ. Academy Press, Tokyo, 2003) 9. Weekes, T. C. et al. Observation of TeV gamma rays form the Crab nebula using the atmospheric Cerenkov imaging technique. Astrophys. J. 342, 379–395 (1989) 10. Aharonian, F. A. et al. The time averaged TeV energy spectrum of Mkn 501 of the extraordinary 1997 outburst as measured with the stereoscopic Cherenkov telescope system of HEGRA. Astron. Astrophys. 349, 11–28 (1999) 11. Bernlöhr, K. et al. The optical system of the H.E.S.S. imaging atmospheric Cherenkov telescopes, Part I: layout and components of the system. Astropart. Phys. 20, 111–128 (2003) 12. Vincent, P. et al. Proc. 28th ICRC (Tsukuba) (eds Kajita, T., Asaoka, Y., Kawachi, A., Matsubara, Y. & Sasaki, M.) 2887–2990 (Univ. Academy Press, Tokyo, 2003) 13. Tanimori, T. et al. Discovery of TeV gamma rays from SN 1006: Further evidence for the supernova remnant origin of cosmic rays. Astrophys. J. 497, L25–L28 (1998) 14. Masterson, C. (H.E.S.S. Collaboration) in Proc. 28th ICRC (Tsukuba) (eds Kajita, T., Asaoka, Y., Kawachi, A., Matsubara, Y. & Sasaki, M.) 2323–2326 (Univ. Academy Press, Tokyo, 2003) 15. Aharonian, F. A. et al. Evidence for TeV gamma ray emission from Cassiopeia A. Astron. Astrophys. 370, 112–120 (2001) 16. Berezhko, E. G., Pühlhofer, G. & Völk, H. J. Gamma-ray emission from Cassiopeia A produced by accelerated cosmic rays. Astron. Astrophys. 400, 971–980 (2003) 17. Slane, P. et al. Nonthermal X-ray emission from the shell-type supernova remnant G347.3–0.5. Astrophys. J. 525, 357–367 (1999) 18. Ellison, D. C., Slane, P. & Gaensler, P. M. Broadband observations and modeling of the shell-type supernova remnant G347.3–0.5. Astrophys. J. 563, 191–201 (2001) 19. Uchiyama, Y., Aharonian, F. A. & Takahashi, T. Fine-structure in the nonthermal X-ray emission of SNR RX J1713.7–3946 revealed by Chandra. Astron. Astrophys. 400, 567–574 (2003) 20. Laming, J. M. A thermal model for the featureless X-ray emission from SN 1006? Astrophys. J. 499, 309–314 (1998) 21. Aharonian, F. A., Drury, L. O'C. & Völk, H. J. GeV/TeV gamma-ray emission from dense molecular clouds overtaken by supernova shells. Astron. Astrophys. 285, 645–647 (1994) 22. Fukui, Y. et al. Discovery of interacting molecular gas toward the TeV gamma-ray peak of the SNR G 347.3–0.5. Publ. Astron. Soc. Jpn 55, L61–L64 (2003) 23. Cassam-Chenaï, A. et al. XMM-Newton observations of the supernova remnant RX J1713.7–3946 and its central source. Astron. Astrophys. (in the press) 24. Koo, B., Kang, J. & McClure-Griffiths, N. in Young Neutron Stars and Their Environments (eds Camilo, F. & Gaensler, B. M.) IAU Symp. 85–86 (Astronomical Society of the Pacific, San Francisco, 2004) 25. Uchiyama, Y., Takahashi, T. & Aharonian, F. A. Flat spectrum X-ray emission from the direction of a molecular cloud associated with SNR RX J1713.7–3946. Publ. Astron. Soc. Jpn 54, L73–L77 (2002) Download references ## Acknowledgements The support of the Namibian authorities and of the University of Namibia in facilitating the construction and operation of HESS is acknowledged. We also thank the following for support: the German Ministry for Education and Research (BMBF), the Max Planck Society, the French Ministry for Research, the CNRS-IN2P3 and the Astroparticle Interdisciplinary Programme of the CNRS, the UK Particle Physics and Astronomy Research Council (PPARC), the IPNP of Charles University, the South African Department of Science and Technology and National Research Foundation, and the University of Namibia. The European Associated Laboratory for Gamma-Ray Astronomy is jointly supported by CNRS and MPG. We appreciate the work of the technical support staff in Berlin, Durham, Hamburg, Heidelberg, Palaiseau, Paris, Saclay and Namibia in the construction and operation of the equipment. We also thank Y. Uchiyama for supplying the ASCA X-ray data shown in Fig. 2. ## Author information ### Authors and Affiliations Authors ### Corresponding author Correspondence to D. Berge. ## Ethics declarations ### Competing interests The authors declare that they have no competing financial interests. ## Rights and permissions Reprints and Permissions ## About this article ### Cite this article Aharonian, F., Akhperjanian, A., Aye, KM. et al. High-energy particle acceleration in the shell of a supernova remnant. Nature 432, 75–77 (2004). https://doi.org/10.1038/nature02960 Download citation • Received: • Accepted: • Issue Date: • DOI: https://doi.org/10.1038/nature02960 ## Further reading • ### Recent Developments in Particle Acceleration at Shocks: Theory and Observations • Silvia Perri • Andrei Bykov • Joe Giacalone Space Science Reviews (2022) • ### The interstellar medium in young supernova remnants: key to the production of cosmic X-rays and$\gamma \$-rays

• Hidetoshi Sano
• Yasuo Fukui

Astrophysics and Space Science (2021)

• ### Miniature supernova shock waves

• Laurent Gremillet
• Martin Lemoine

Nature Physics (2020)

• ### Electron acceleration in laboratory-produced turbulent collisionless shocks

• F. Fiuza
• H.-S. Park

Nature Physics (2020)

• ### The golden age of high-energy gamma-ray astronomy: the Cherenkov Telescope Array in the multimessenger era

• Patrizia A. Caraveo

La Rivista del Nuovo Cimento (2020)

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.