Universidad Complutense de Madrid
E-Prints Complutense

MAGIC reveals a complex morphology within the unidentified gamma-ray source HESS J1857+026



Último año

Antoranz Canales, Pedro y Barrio Uña, Juan Abel y Contreras González, José Luis y Fonseca González, Mª Victoria y López Moya, Marcos y Miranda Pantoja, José Miguel y Satalecka, Konstanzja y Scapin, Valeria (2014) MAGIC reveals a complex morphology within the unidentified gamma-ray source HESS J1857+026. Astronomy & Astrophysics, 571 . ISSN 0004-6361

Vista previa

URL Oficial: http://dx.doi.org/10.1051/0004-6361/201423517


Aims. HESS J1857+026 is an extended TeV gamma-ray source that was discovered by H. E. S. S. as part of its Galactic plane survey. Given its broadband spectral energy distribution and its spatial coincidence with the young energetic pulsar PSR J1856+0245, the source has been put forward as a pulsar wind nebula (PWN) candidate. MAGIC has performed follow-up observations aimed at mapping the source down to energies approaching 100 GeV in order to better understand its complex morphology. Methods. HESS J1857+026 was observed by MAGIC in 2010, yielding 29 h of good quality stereoscopic data that allowed us to map the source region in two separate ranges of energy. Results. We detected very-high-energy gamma-ray emission from HESS J1857+026 with a significance of 12 sigma above 150 GeV. The differential energy spectrum between 100 GeV and 13 TeV is described well by a power law function dN/dE = N-0(E/1TeV)(-Gamma) with N-0 = (5.37 +/- 0.44(stat) +/- 1.5(sys)) X 10(-12) (TeV-1 cm(-2) s(-1)) and Gamma = 2.16 +/- 0.07(stat) +/- 0.15(sys), which bridges the gap between the GeV emission measured by Fermi-LAT and the multi-TeV emission measured by H.E.S.S.. In addition, we present a detailed analysis of the energy-dependent morphology of this region. We couple these results with archival multiwavelength data and outline evidence in favor of a two-source scenario, whereby one source is associated with a PWN, while the other could be linked with a molecular cloud complex containing an HII region and a possible gas cavity.

Tipo de documento:Artículo
Información Adicional:

© ESO 2014. We would like to thank the Instituto de Astrofísica de Canarias for the excellent working conditions at the Observatorio del Roque de los Muchachos in La Palma. The support of the German BMBF and MPG, the Italian INFN, the Swiss National Fund SNF, and the Spanish MICINN is gratefully acknowledged. This work was also supported by the CPAN CSD2007-00042 and MultiDark CSD2009-00064 projects of the Spanish Consolider-Ingenio 2010 programme, by grant 127740 of the Academy of Finland, by the DFG Cluster of Excellence “Origin and Structure of the Universe”, by the Croatian Science Foundation Project 09/176, by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3, and by the Polish MNiSzW grant 745/N-HESSMAGIC/2010/0.

Palabras clave:H-II regions; Star-forming regions; Galactic ring survey; Pulsar wind nebulae; Supernova Remnant; Inner galaxy; Atomic gas; Emission; Constraints; Absorption.
Materias:Ciencias > Física > Electricidad
Ciencias > Física > Electrónica
Ciencias > Física > Física nuclear
Código ID:29331
Depositado:26 Mar 2015 11:00
Última Modificación:26 Mar 2015 11:00

Descargas en el último año

Sólo personal del repositorio: página de control del artículo