Discovery of VHE $\gamma$-ray emission from the SNR G54.1+0.3

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We report the discovery of very high energy gamma-ray emission from the direction of the SNR G54.1+0.3 using the VERITAS ground-based gamma-ray observatory.

• The TeV signal has an overall significance of 6.8$\sigma$ and appears point-like given the 5$^{arcminute}$ resolution of the instrument.
• The integral flux above 1 TeV is 2.5% of the Crab Nebula flux and significant emission is measured between 250 GeV and 4 TeV, well described by a power-law energy spectrum dN/dE $\sim$ E$^{-\Gamma}$ with a photon index $\Gamma= 2.39\pm0.23_{stat}\pm0.30_{sys}$.
• We find no evidence of time variability among observations spanning almost two years.