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arXiv · 1104.2770

Very high-energy observations of the two high-frequency peaked BL Lac objects 1ES 1218+304 and H 1426+428

C. Mueller·N. Akhter·J. Ball·D. A. Bramel·J. Carson·C. E. Covault·D. Driscoll·P. Fortin·D. M. Gingrich·D. S. Hanna·A. Jarvis·J. Kildea·T. Lindner·R. Mukherjee·R. A. Ong·K. Ragan·R. A. Scalzo·D. A. Williams·J. Zweerink
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Abstract

We present results of very-high-energy gamma-ray observations (E > 160 GeV) of two high-frequency-peaked BL Lac (HBL) objects, 1ES 1218+304 and H 1426+428, with the Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE). Both sources are very-high-energy gamma-ray emitters above 100 GeV, detected using ground-based Cherenkov telescopes. STACEE observations of 1ES 1218+304 and H 1426+428 did not produce detections; we present 99% CL flux upper limits for both sources, assuming spectral indices measured mostly at higher energies.

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C. Mueller, N. Akhter, J. Ball, D. A. Bramel, J. Carson, C. E. Covault, D. Driscoll, P. Fortin, D. M. Gingrich, D. S. Hanna, A. Jarvis, J. Kildea, T. Lindner, R. Mukherjee, R. A. Ong, K. Ragan, R. A. Scalzo, D. A. Williams, J. Zweerink. 2011-04-14. Very high-energy observations of the two high-frequency peaked BL Lac objects 1ES 1218+304 and H 1426+428. https://doi.org/10.1016/j.astropartphys.2011.01.010

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