TeV γ-ray observations of the young synchrotron-dominated SNRs G1.9+0.3 and G330.2+1.0 with H.E.S.S

Abstract

The non-thermal nature of the X-ray emission from the shell-type supernova remnants (SNRs) G1.9+0.3 and G330.2+1.0 is an indication of intense particle acceleration in the shock fronts of both objects. This suggests that the SNRs are prime candidates for very-high-energy (VHE; E $>$ 0.1 TeV) γ-ray observations. G1.9+0.3, recently established as the youngest known SNR in the Galaxy, also offers a unique opportunity to study the earliest stages of SNR evolution in the VHE domain. The purpose of this work is to probe the level of VHE γ-ray emission from both SNRs and use this to constrain their physical properties. Observations were conducted with the H.E.S.S. (High Energy Stereoscopic System) Cherenkov telescope array over a more than six-year period spanning 2004-2010. The obtained data have effective livetimes of 67 h for G1.9+0.3 and 16 h for G330.2+1.0. The data are analyzed in the context of the multi-wavelength observations currently available and in the framework of both leptonic and hadronic particle acceleration scenarios. No significant γ-ray signal from G1.9+0.3 or G330.2+1.0 was detected. Upper limits (99% confidence level) to the TeV flux from G1.9+0.3 and G330.2+1.0 for the assumed spectral index Γ = 2.5 were set at 5.6 $\times$ 10${}^{-13}$ cm${}^{-2}$ s${}^{-1}$ above 0.26 TeV and 3.2 $\times$ 10${}^{-12}$ cm${}^{-2}$ s${}^{-1}$ above 0.38 TeV, respectively. In a one-zone leptonic scenario, these upper limits imply lower limits on the interior magnetic field to B${}_{G1.9}$ $\gtrsim$ 11 μG for G1.9+0.3 and to B${}_{G330}$ $\gtrsim$ 8 μG for G330.2+1.0. In a hadronic scenario, the low ambient densities and the large distances to the SNRs result in very low predicted fluxes, for which the H.E.S.S. upper limits are not constraining.

arXiv comment9 pages, 2 figures, 4 tables. Accepted for publication in MNRAS

References in corpus (32)

• A Unified Approach to the Classical Statistical Analysis of Small Signals
• Design Concepts for the Cherenkov Telescope Array
• Observations of the Crab Nebula with H.E.S.S
• The H.E.S.S. survey of the Inner Galaxy in very high-energy gamma-rays
• High-energy particle acceleration in the shell of a supernova remnant
• Very high energy gamma rays from the direction of Sagittarius A*
• Background Modelling in Very-High-Energy gamma-ray Astronomy
• Primary particle acceleration above 100 TeV in the shell-type Supernova Remnant RX J1713.7-3946 with deep H.E.S.S. observations
• A high performance likelihood reconstruction of gamma-rays for Imaging Atmospheric Cherenkov Telescopes
• A detailed spectral and morphological study of the gamma-ray supernova remnant RX J1713.7-3946 with H.E.S.S
• Analytical solutions for energy spectra of electrons accelerated by nonrelativistic shock-waves in shell type supernova remnants
• The Youngest Galactic Supernova Remnant: G1.9+0.3
• H.E.S.S. observations of the supernova remnant RX J0852.0-4622: shell-type morphology and spectrum of a widely extended VHE gamma-ray source
• HESS Observations and VLT Spectroscopy of PG 1553+113
• Detection of TeV gamma-ray Emission from the Shell-Type Supernova Remnant RX J0852.0-4622 with H.E.S.S
• First detection of VHE gamma-rays from SN 1006 by H.E.S.S
• The optical system of the H.E.S.S. imaging atmospheric Cherenkov telescopes, Part I: layout and components of the system
• Inverse Compton Emission from Galactic Supernova Remnants: Effect of the Interstellar Radiation Field
• Gamma-Hadron Separation in Very-High-Energy gamma-ray astronomy using a multivariate analysis method
• Angular, spectral, and time distributions of highest energy protons and associated secondary gamma-rays and neutrinos propagating through extragalactic magnetic and radiation fields
• The Southern Galactic Plane Survey: The Test Region
• The Trigger System of the H.E.S.S. Telescope Array
• Variation of cosmic ray injection across supernova shocks
• The radio expansion and brightening of the very young supernova remnant G1.9+0.3
• Expansion of the Youngest Galactic Supernova Remnant G1.9+0.3
• Radioactive Scandium in the Youngest Galactic Supernova Remnant G1.9+0.3
• X-ray Spectral Variations in the Youngest Galactic Supernova Remnant G1.9+0.3
• Nonthermal X-Rays from Supernova Remnant G330.2+1.0 and the Characteristics of its Central Compact Object
• Discovery of a Candidate Central Compact Object in the Galactic Nonthermal SNR G330.2+1.0
• A 20 Year Radio Light Curve for the Young Supernova Remnant G1.9+0.3
• Discovery of a Featureless X-Ray Spectrum in the Supernova Remnant Shell of G330.2+1.0
• Nonthermal properties of supernova remnant G1.9+0.3

Cited by in corpus (11)

• Population study of Galactic supernova remnants at very high $\gamma$-ray energies with H.E.S.S.
• The Hard X-Ray View of the Young Supernova Remnant G1.9+0.3
• Non-thermal emission from the reverse shock of the youngest galactic Supernova remnant G1.9+0.3
• Time evolution of broadband non-thermal emission from supernova remnants in different circumstellar environments
• On the energy distribution of relativistic electrons in the young supernova remnant G1.9+0.3
• Hydrodynamical and radio evolution of young supernova remnant G1.9+0.3 based on the model of diffusive shock acceleration
• A Deep X-ray View of the Synchrotron-Dominated Supernova Remnant G330.2+1.0
• The two most recent thermonuclear supernovae in the Local Group: radio constraints on their progenitors and evolution
• Long-term evolution of non-thermal emission from Type Ia and core-collapse supernova remnants in a diversified circumstellar medium
• Brightening and Fading in the Youngest Galactic Supernova Remnant G1.9+0.3: 13 years of monitoring with the Chandra X-ray Observatory
• H.E.S.S.: The High Energy Stereoscopic System