The Astrophysical Journal Letters, 684:L73–L77

ArXiv:0808.0889

We report the detection of very high energy γ-ray emission from the intermediate-frequency-peaked BL Lacertae object W Comae ( ) by VERITAS. The source was observed between 2008 January and April. A strong outburst of γ-ray emission was measured in the middle of March, lasting for only 4 days. The energy spectrum measured during the two highest flare nights is fit by a power law and is found to be very steep, with a differential photon spectral index of . The integral photon flux above during those two nights corresponds to roughly of the flux from the Crab Nebula. Quasi-simultaneous Swift observations at X-ray energies were triggered by the VERITAS observations. The spectral energy distribution of the flare data can be described by synchrotron self-Compton (SSC) or external Compton (EC) leptonic jet models.