MAGIC observations of PG 1553+113 during a multiwavelength campaign in July 2006 (Research Note)

The active galactic nucleus PG 1553+113 was observed by the MAGIC telescope in July 2006 during a multiwavelength campaign, in which telescopes in the optical, X-ray, and very high energies participated. Although the MAGIC data were affected by strong atmospheric absorption (calima), they were analyzed after applying a correction. In 8.5 h, a signal was detected with a significance of 5.0σ. The integral flux above 150 GeV was (2.6 ± 0.9) × 10 −7 ph s −1 m −2 . By fitting the differential energy spectrum with a power law, a spectral index of −4.1 ± 0. 3w as obtained.