STACEE Observations of 1ES 1218+304

TL;DR

This paper reports on high-energy gamma-ray observations of the X-ray bright BL Lac object 1ES 1218+304 using STACEE, confirming its gamma-ray emission above 100 GeV and contributing to understanding high-energy astrophysical sources.

Contribution

First analysis of 1ES 1218+304 with STACEE, providing new observational data at energies above 100 GeV and supporting previous detections by MAGIC and VERITAS.

Findings

Detection of gamma-ray emission above 100 GeV from 1ES 1218+304.

Confirmation of the source as a high-energy gamma-ray emitter.

Complementary observations to MAGIC and VERITAS results.

Abstract

We present the analysis and results of recent high-energy gamma-ray observations of the high energy-peaked BL Lac (HBL) object 1ES 1218+304 with the Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE). 1ES 1218+304 is an X-ray bright HBL at a redshift z=0.182. It has been predicted to be a gamma-ray emitter above 100 GeV, detectable by ground-based Cherenkov telescopes. Recently this source has been detected by MAGIC and VERITAS, confirming these predictions. STACEE's sensitivity to astrophysical sources at energies above 100 GeV allows it to explore high energy sources such as X-ray bright active galaxies and gamma-ray bursts. We present results from STACEE observations of 1ES 1218+304 in the 2006 and 2007 observing seasons.