Resolving the Crab pulsar wind nebula at teraelectronvolt energies
Abstract
The Crab nebula is one of the most studied cosmic particle accelerators, shining brightly across the entire electromagnetic spectrum up to very high-energy gamma rays. It is known from radio to gamma-ray observations that the nebula is powered by a pulsar, which converts most of its rotational energy losses into a highly relativistic outflow. This outflow powers a pulsar wind nebula (PWN), a region of up to 10~light-years across, filled with relativistic electrons and positrons. These particles emit synchrotron photons in the ambient magnetic field and produce very high-energy gamma rays by Compton up-scattering of ambient low-energy photons. While the synchrotron morphology of the nebula is well established, it was up to now not known in which region the very high-energy gamma rays are emitted. Here we report that the Crab nebula has an angular extension at gamma-ray energies of 52 arcseconds (assuming a Gaussian source width), significantly larger than at X-ray energies. This result closes a gap in the multi-wavelength coverage of the nebula, revealing the emission region of the highest energy gamma rays. These gamma rays are a new probe of a previously inaccessible electron and positron energy range. We find that simulations of the electromagnetic emission reproduce our new measurement, providing a non-trivial test of our understanding of particle acceleration in the Crab nebula.
Cite
@article{arxiv.1909.09494,
title = {Resolving the Crab pulsar wind nebula at teraelectronvolt energies},
author = {H. E. S. S. Collaboration and H. Abdalla and F. Aharonian and F. Ait Benkhali and E. O. Angüner and M. Arakawa and C. Arcaro and C. Arm and M. Backes and M. Barnard and Y. Becherini and J. Becker Tjus and D. Berge and K. Bernlöhr and R. Blackwell and M. Böttcher and C. Boisson and J. Bolmont and S. Bonnefoy and P. Bordas and J. Bregeon and F. Brun and P. Brun and M. Bryan and M. Büchele and T. Bulik and T. Bylund and M. Capasso and S. Caroff and A. Carosi and S. Casanova and M. Cerruti and N. Chakraborty and T. Ch and S. Ch and R. C. G. Chaves and A. Chen and S. Colafrancesco and B. Condon and I. D. Davids and C. Deil and J. Devin and P. deWilt and L. Dirson and A. Djannati-Ataï and A. Dmytriiev and A. Donath and V. Doroshenko and L. O'C. Drury and J. Dyks and K. Egberts and G. Emery and J. -P. Ernenwein and S. Eschbach and S. Fegan and A. Fiasson and G. Fontaine and S. Funk and M. Füßling and S. Gabici and Y. A. Gallant and F. Gaté and G. Giavitto and D. Glawion and J. F. Glicenstein and D. Gottschall and M. -H. Grondin and J. Hahn and M. Haupt and G. Heinzelmann and G. Henri and G. Hermann and J. A. Hinton and W. Hofmann and C. Hoischen and T. L. Holch and M. Holler and D. Horns and D. Huber and H. Iwasaki and A. Jacholkowska and M. Jamrozy and D. Jankowsky and F. Jankowsky and L. Jouvin and I. Jung-Richardt and M. A. Kastendieck and K. Katarzyński and M. Katsuragawa and U. Katz and D. Khangulyan and B. Khélifi and J. King and S. Klepser and W. Kluźniak and Nu. Komin and K. Kosack and M. Kraus and G. Lamanna and J. Lau and J. Lefaucheur and A. Lemière and M. Lemoine-Goumard and J. -P. Lenain and E. Leser and T. Lohse and R. López-Coto and I. Lypova and D. Malyshev and V. Mar and A. Marcowith and C. Mariaud and G. Martí-Devesa and R. Marx and G. Maurin and P. J. Meintjes and A. M. W. Mitchell and R. Moderski and M. Mohamed and L. Mohrmann and C. Moore and E. Moulin and T. Murach and S. Nakashima and M. de Naurois and H. Ndiyavala and F. Niederwanger and J. Niemiec and L. Oakes and P. O'Brien and H. Odaka and S. Ohm and M. Ostrowski and I. Oya and M. Panter and R. D. Parsons and C. Perennes and P. -O. Petrucci and B. Peyaud and Q. Piel and S. Pita and V. Poireau and A. Priyana Noel and D. A. Prokhorov and H. Prokoph and G. Pühlhofer and M. Punch and A. Quirrenbach and S. Raab and R. Rauth and A. Reimer and O. Reimer and M. Renaud and F. Rieger and L. Rinchiuso and C. Romoli and G. Rowell and B. Rudak and E. Ruiz-Velasco and V. Sahakian and S. Saito and D. A. Sanchez and A. Santangelo and M. Sasaki and R. Schlickeiser and F. Schüssler and A. Schulz and H. Schutte and U. Schwanke and S. Schwemmer and M. Seglar-Arroyo and M. Senniappan and A. S. Seyffert and N. Shafi and I. Shilon and K. Shiningayamwe and R. Simoni and A. Sinha and H. Sol and A. Specovius and M. Spir-Jacob and Ł. Stawarz and R. Steenkamp and C. Stegmann and C. Steppa and T. Takahashi and J. -P. Tavernet and T. Tavernier and A. M. Taylor and R. Terrier and D. Tiziani and M. Tluczykont and C. Trichard and M. Tsirou and N. Tsuji and R. Tuffs and Y. Uchiyama and D. J. van der Walt and C. van Eldik and C. van Rensburg and B. van Soelen and G. Vasileiadis and J. Veh and C. Venter and P. Vincent and J. Vink and F. Voisin and H. J. Völk and T. Vuillaume and Z. Wadiasingh and S. J. Wagner and R. M. Wagner and R. White and A. Wierzcholska and R. Yang and H. Yoneda and D. Zaborov and M. Zacharias and R. Zanin and A. A. Zdziarski and A. Zech and A. Ziegler and J. Zorn and N. Żywucka},
journal= {arXiv preprint arXiv:1909.09494},
year = {2019}
}
Comments
23 pages, 5 figures