Characterising the VHE diffuse emission in the central 200 parsecs of our Galaxy with HESS

Journal article
(Original article)


Publication Details

Author(s): Abdalla H, Abramowski A, Aharonian F, Benkhali FA, Akhperjanian AG, Andersson T, Anguener EO, Arakawa M, Arrieta M, Aubert P, Backes M, Balzer A, Barnard M, Becherini Y, Tjus JB, Berge D, Bernhard S, Bernloehr K, Blackwell R, Boettcher M, Boisson C, Bolmont J, Bonnefoy S, Bordas P, Bregeon J, Brun F, Brun P, Bryan M, Büchele M, Bulik T, Capasso M, Carr J, Casanova S, Cerruti M, Chakraborty N, Chaves RCG, Chen A, Chevalier J, Coffaro M, Colafrancesco S, Cologna G, Condon B, Conrad J, Cui Y, Davids ID, Decock J, Degrange B, Deil C, Devin J, Dewilt P, Dirson L, Djannati-Atai A, Domainko W, Donath A, Drury LO, Dutson K, Dyks J, Edwards T, Egberts K, Eger P, Ernenwein JP, Eschbach S, Farnier C, Fegan S, Fernandes MV, Fiasson A, Fontaine G, Foerster A, Funk S, Fuessling M, Gabici S, Gallant YA, Garrigoux T, Giavitto G, Giebels B, Glicenstein JF, Gottschall D, Goyal A, Grondin MH, Hahn J, Haupt M, Hawkes J, Heinzelmann G, Henri G, Hermann G, Hinton JA, Hofmann W, Hoischen C, Holch TL, Holler M, Horns D, Ivascenko A, Iwasaki H, Jacholkowska A, Jamrozy M, Janiak M, Jankowsky D, Jankowsky F, Jingo M, Jogler T, Jouvin L, Jung-Richardt I, Kastendieck MA, Katarzynski K, Katsuragawa M, Katz U, Kerszberg D, Khangulyan D, Khelifi B, King J, Klepser S, Klochkov D, Kluzniak W, Kolitzus D, Komin N, Kosack K, Krakau S, Kraus M, Krueger PP, Laffon H, Lamanna G, Lau J, Lees JP, Lefaucheur J, Lefranc V, Lemiere A, Lemoine-Goumard M, Lenain JP, Leser E, Lohse T, Lorentz M, Liu R, Lopez-Coto R, Lypova I, Marandon V, Marcowith A, Mariaud C, Marx R, Maurin G, Maxted N, Mayer M, Meintjes PJ, Meyer M, Mitchell AMW, Moderski R, Mohamed M, Mohrmann L, Mora K, Moulin E, Murach T, Nakashima S, De Naurois M, Niederwanger F, Niemiec J, Oakes L, O'Brien P, Odaka H, Ohm S, Ostrowski M, Oya I, Padovani M, Panter M, Parsons RD, Pekeur NW, Pelletier G, Perennes C, Petrucci PO, Peyaud B, Piel Q, Pita S, Poon H, Prokhorov D, Prokoph H, Puehlhofer G, Punch M, Quirrenbach A, Raab S, Rauth R, Reimer A, Reimer O, Renaud M, De Los Reyes R, Richter S, Rieger F, Romoli C, Rowell G, Rudak B, Rulten CB, Sahakian V, Saito S, Salek D, Sanchez DA, Santangelo A, Sasaki M, Schlickeiser R, Schuessler F, Schulz A, Schwanke U, Schwemmer S, Seglar-Arroyo M, Settimo M, Seyffert AS, Shafi N, Shilon I, Simoni R, Sol H, Spanier F, Spengler G, Spies F, Stawarz L, Steenkamp R, Stegmann C, Stycz K, Sushch I, Takahashi T, Tavernet JP, Tavernier T, Taylor AM, Terrier R, Tibaldo L, Tiziani D, Tluczykont M, Trichard C, Tsuji N, Tuffs R, Uchiyama Y, Van Der Walt DJ, van Eldik C, Van Rensburg C, Van Soelen B, Vasileiadis G, Veh J, Venters C, Viana A, Vincent P, Vink J, Voisin F, Voelk HJ, Vuillaume T, Wadiasingh Z, Wagner SJ, Wagner P, Wagner RM, White R, Wierzcholska A, Willmann P, Wörnlein A, Wouters D, Yang R, Zaborov D, Zacharias M, Zanin R, Zdziarski AA, Zech A, Zefi F, Ziegler A, Zywucka N
Journal: Astronomy & Astrophysics
Publisher: EDP SCIENCES S A
Publication year: 2018
Volume: 612
ISSN: 1432-0746


Abstract

The diffuse very high-energy (VHE; > 100 GeV) gamma-ray emission observed in the central 200 pc of the Milky Way by H.E.S.S. was found to follow dense matter distribution in the central molecular zone (CMZ) up to a longitudinal distance of about 130 pc to the Galactic centre (GC), where the flux rapidly decreases. This was initially interpreted as the result of a burst-like injection of energetic particles 104 yr ago, but a recent more sensitive H.E.S.S. analysis revealed that the cosmic-ray (CR) density profile drops with the distance to the centre, making data compatible with a steady cosmic PeVatron at the GC. In this paper, we extend this analysis to obtain, for the first time, a detailed characterisation of the correlation with matter and to search for additional features and individual gamma-ray sources in the inner 200 pc. Taking advantage of 250 h of H.E.S.S. data and improved analysis techniques, we perform a detailed morphology study of the diffuse VHE emission observed from the GC ridge and reconstruct its total spectrum. To test the various contributions to the total gamma-ray emission, we used an iterative 2D maximum-likelihood approach that allows us to build a phenomenological model of the emission by summing a number of different spatial components. We show that the emission correlated with dense matter covers the full CMZ and that its flux is about half the total diffuse emission flux. We also detect some emission at higher latitude that is likely produced by hadronic collisions of CRs in less dense regions of the GC interstellar medium. We detect an additional emission component centred on the GC and extending over about 15 pc that is consistent with the existence of a strong CR density gradient and confirms the presence of a CR accelerator at the very centre of our Galaxy. We show that the spectrum of full ridge diffuse emission is compatible with that previously derived from the central regions, suggesting that a single population of particles fills the entire CMZ. Finally, we report the discovery of a VHE gamma-ray source near the GC radio arc and argue that it is produced by the pulsar wind nebula candidate G0.13-0.11.


FAU Authors / FAU Editors

Büchele, Matthias
Lehrstuhl für Physik
Eschbach, Stefan
Lehrstuhl für Physik
Funk, Stefan Prof. Dr.
Lehrstuhl für Physik
Jankowsky, David
Lehrstuhl für Physik
Jogler, Tobias Dr.
Lehrstuhl für Physik
Jung-Richardt, Ira PD Dr.
Lehrstuhl für Physik
Katz, Uli Prof. Dr.
Lehrstuhl für Experimentalphysik (Astroteilchenphysik)
Mohrmann, Lars Dr.
Lehrstuhl für Physik
Raab, Susanne
Lehrstuhl für Physik
Sasaki, Manami Prof. Dr.
Professur für Multiwellenlängenastronomie
Shilon, Idan
Lehrstuhl für Physik
Tiziani, Domenico
Professur für Experimentalphysik
van Eldik, Christopher Prof. Dr.
Professur für Experimentalphysik
Veh, Johannes Dr.
Professur für Experimentalphysik
Willmann, Philipp
Lehrstuhl für Experimentalphysik (Astroteilchenphysik)
Wörnlein, André
Lehrstuhl für Experimentalphysik (Astroteilchenphysik)
Ziegler, Alexander
Professur für Experimentalphysik


How to cite

APA:
Abdalla, H., Abramowski, A., Aharonian, F., Benkhali, F.A., Akhperjanian, A.G., Andersson, T.,... Zywucka, N. (2018). Characterising the VHE diffuse emission in the central 200 parsecs of our Galaxy with HESS. Astronomy & Astrophysics, 612. https://dx.doi.org/10.1051/0004-6361/201730824

MLA:
Abdalla, H., et al. "Characterising the VHE diffuse emission in the central 200 parsecs of our Galaxy with HESS." Astronomy & Astrophysics 612 (2018).

BibTeX: 

Last updated on 2019-18-07 at 07:27