Suzaku Observation of the Diffuse X-Ray Emission from the Open Cluster Westerlund 2: a Hypernova Remnant?

Abstract

We present the analysis of Suzaku observations of the young open cluster Westerlund 2, which is filled with diffuse X-ray emission. We found that the emission consists of three thermal components or two thermal and one non-thermal components. The upper limit of the energy flux of the non-thermal component is smaller than that in the TeV band observed with H.E.S.S. This may indicate that active particle acceleration has stopped in this cluster, and that the accelerated electrons have already cooled. The gamma-ray emission observed with H.E.S.S. is likely to come from high-energy protons, which hardly cool in contrast with electrons. Metal abundances of the diffuse X-ray gas may indicate the explosion of a massive star in the past.

Accepted for publication in PASJ

References in corpus (10)

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Cited by in corpus (14)

• Fermi-LAT Search for Pulsar Wind Nebulae around gamma-ray Pulsars
• Revisiting the Westerlund 2 Field with the H.E.S.S. Telescope Array
• The Chandra Carina Complex Project: Deciphering the Enigma of Carina's Diffuse X-ray Emission
• Excesses of Cosmic Ray Spectra from A Single Nearby Source
• Slow Diffusion of Cosmic-Rays around a Supernova Remnant
• Feedback from Winds and Supernovae in Massive Stellar Clusters - II. X-Ray Emission
• Searching for Diffuse Nonthermal X-Rays from the Superbubbles N11 and N51D in the Large Magellanic Cloud
• High resolution radio emission from RCW 49/Westerlund 2
• Probing the hadronic nature of the gamma-ray emission associated with Westerlund 2
• The jet and arc molecular clouds toward Westerlund 2, RCW 49, and HESS J1023-575; 12CO and 13CO (J=2-1 and J=1-0) observations with NANTEN2 and Mopra Telescope
• X-ray emission from Westerlund 2 detected by SRG/ART-XC and Chandra: search for radiation of TeV leptons
• Galactic Structure Toward the Carina Tangent
• The Environment around the Young Massive Star Cluster RSGC 1 and HESS J1837-069
• CANGAROO-III observation of TeV gamma rays from the unidentified gamma-ray source HESS J1614-518