Deep radio images of the HEGRA and Whipple TeV sources in the Cygnus OB2 region

Abstract

Context. The modern generation of Cherenkov telescopes has revealed a new population of gamma-ray sources in the Galaxy. Some of them have been identified with previously known X-ray binary systems while other remain without clear counterparts a lower energies. Our initial goal here was reporting on extensive radio observations of the first extended and yet unidentified source, namely TeV J2032+4130. This object was originally detected by the HEGRA telescope in the direction of the Cygnus OB2 region and its nature has been a matter of debate during the latest years. Aims. We aim to pursue our radio exploration of the TeV J2032+4130 position that we initiated in a previous paper but taking now into account the latest results from new Whipple and MILAGRO TeV telescopes. Methods. Our investigation is mostly based on interferometric radio observations with the Giant Metre Wave Radio Telescope (GMRT) close to Pune (India) and the Very Large Array (VLA) in New Mexico (USA). We also conducted near infrared observations with the 3.5 m telescope and the OMEGA2000 camera at the Centro Astronomico Hispano Aleman (CAHA) in Almeria (Spain). Results. We present deep radio maps centered on the TeV J2032+4130 position at different wavelengths. In particular, our 49 and 20 cm maps cover a field of view larger than half a degree that fully includes the Whipple position and the peak of MILAGRO emission. Our most important result here is a catalogue of 153 radio sources detected at 49 cm within the GMRT antennae primary beam with a full width half maximum (FWHM) of 43 arc-minute. Moreover, our multi-configuration VLA images reveal the non-thermal extended emission previously reported by us with improved angular resolution.

arXiv comment10 pages, 8 figures, 1 online catalogue. Accepted for publication in Astronomy & Astrophysics

References in corpus (15)

• Radio galaxies with a `double-double' morphology: I - Analysis of the radio properties and evidence for interrupted activity in active galactic nuclei
• Discovery of TeV Gamma-Ray Emission from the Cygnus Region of the Galaxy
• An unidentified TeV source in the vicinity of Cygnus OB2
• The unidentified TeV source (TeVJ2032+4130) and surrounding field: Final HEGRA IACT-System results
• The Deep X-ray Radio Blazar Survey (DXRBS). II. New Identifications
• Serendipitous discovery of the unidentified extended TeV gamma-ray source HESS J1303-631
• Electromagnetic radiation initiated by hadronic jets from microquasars in the ISM
• High-energy gamma-rays from stellar associations
• CHANDRA/VLA Follow-up of TeV J2032+4131, the Only Unidentified TeV Gamma-ray Source
• Deep 610-MHz GMRT observations of the Spitzer extragalactic First Look Survey field - I. Observations, data analysis and source catalogue
• Search for a Point-Source Counterpart of the Unidentified Gamma-Ray Source TeV J2032+4130 in Cygnus
• Observations of the Unidentified TeV Gamma-Ray Source TeV J2032+4130 with the Whipple Observatory 10 m Telescope
• Deeper Chandra Follow-up of Cygnus TeV Source Perpetuates Mystery
• The population of radio sources in the field of the unidentified gamma-ray source TeV J2032+4130
• AGNs and microquasars as high energy gamma-ray sources

Cited by in corpus (8)

• Radio detection of LAT PSRs J1741-2054 and J2032+4127: no longer just gamma-ray pulsars
• MAGIC observations of the unidentified TeV gamma-ray source TeV J2032+4130
• TeV J2032+4130: a not-so-dark Accelerator?
• Radio counterparts of gamma-ray sources in the Cygnus region
• The Molecular Environment of the Gamma-ray Source TeV J2032+4130
• COBRaS: The e-MERLIN 21 cm Legacy survey of Cygnus OB2
• Investigation of the double-lobed sources of the Cygnus constellation core
• Analysis of the Emission and Morphology of the Pulsar Wind Nebula Candidate HAWC J2031+415