Observation of the Monoceros Loop SNR region with the HEGRA system of IACTs

¹ Max-Planck-Institut für Kernphysik, Postfach 103980, 9029 Heidelberg, Germany
² Yerevan Physics Institute, Alikhanian Br. 2, 375036 Yerevan, Armenia
³ Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 149, 22761 Hamburg, Germany
⁴ Universität Kiel, Institut für Experimentelle und Angewandte Physik, Leibnizstraße 15-19, 24118 Kiel, Germany
⁵ Universität Wuppertal, Fachbereich Physik, Gaußstr. 20, 42097 Wuppertal, Germany
⁶ Max-Planck-Institut für Physik, Föhringer Ring 6, 80805 München, Germany
⁷ Universidad Complutense, Facultad de Ciencias Físicas, Ciudad Universitaria, 28040 Madrid, Spain
⁸ Institut de Física d'Altes Energies, UAB, Edifici Cn, 08193, Bellaterra (Barcelona), Spain
⁹ On leave from Altai State University, Dimitrov Street 66, 656099 Barnaul, Russia
¹⁰ Home institute: University Lodz, Poland

Corresponding author: F. Lucarelli, lucarel@gae.ucm.es

Received: 13 June 2003
Accepted: 9 December 2003

Abstract

The array of 5 imaging atmospheric Čerenkov telescopes (IACTs) deployed at La Palma (Canary Islands), and operated by the HEGRA (High Energy Gamma Ray Astronomy) collaboration, was used for observations of the Monoceros Loop SNR region for a total of about 120 hrs and 20 hrs in ON-source and OFF-source mode, respectively. The giant molecular cloud Rosette Nebula appears in the sky region, close to the south-east part of the SNR rim. Using the HEGRA system of IACTs of rather large field of view (4.3 degree in diameter), we have mapped the extended sky region of associated with the Monoceros SNR/Rosette Nebula, which is centered towards the hard spectrum X-ray point source SAX J0635+533. The EGRET unidentified source of diffuse γ-ray emission (3EG J0634+0521) observed in the energy range between 100 MeV–10 GeV, was effectively in the field of view of our present observations. Also, the GeV source GeV J0633+0645 was within the available field of view. The performance of the IACTs array reveals an energy threshold of 500 GeV and an angular resolution of  for γ-rays. In what follows, we present the result of the data analysis and its physical interpretation.