BL Lac object 1ES 0647+250, a decade of MWL observations

Abstract

<p>The high-peaked BL Lac object 1ES 0647+250 is one of the few distant blazars detected at very-high-energy (VHE, E>100 GeV) γ rays during non-flaring activity. Its redshift is still uncertain, with a recently proposed lower limit of <em>z </em>>0.29. This blazar was first detected by the MAGIC telescopes between 2009 and 2011 during its low state, displaying a flux of around 2% of the Crab Nebula above 100 GeV, but it has shown several periods of high activity, where the VHE γ-ray flux increased by more than one order of magnitude.<br>The VHE spectra of four observed periods are characterized and the redshift of this source is estimated using the HE and VHE spectral shapes. The multi-wavelength data set collected from 2009 to 2020 introduced in this work will serve as the seed for further studies, including detailed studies of the broad-band spectral energy distribution for different activity levels and multi-band variability and correlation studies.<br></p>