A Very High Energy $\gamma$-Ray Survey towards the Cygnus Region of the Galaxy

Abstract

We present results from deep observations towards the Cygnus region using 300 hours of very-high-energy (VHE) $\gamma$-ray data taken with the VERITAS Cherenkov telescope array and over seven years of high-energy $\gamma$-ray data taken with the Fermi satellite at an energy above 1 GeV. As the brightest region of diffuse $\gamma$-ray emission in the northern sky, the Cygnus region provides a promising area to probe the origins of cosmic rays. We report the identification of a potential Fermi-LAT counterpart to VER J2031+415 (TeV J2032+4130), and resolve the extended VHE source VER J2019+368 into two source candidates (VER J2018+367* and VER J2020+368*) and characterize their energy spectra. The Fermi-LAT morphology of 3FGL 2021.0+4031e (the Gamma-Cygni supernova remnant) was examined and a region of enhanced emission coincident with VER J2019+407 was identified and jointly fit with the VERITAS data. By modeling 3FGL J2015.6+3709 as two sources, one located at the location of the pulsar wind nebula CTB 87 and one at the quasar QSO J2015+371, a continuous spectrum from 1 GeV to 10 TeV was extracted for VER J2016+371 (CTB 87). An additional 71 locations coincident with Fermi-LAT sources and other potential objects of interest were tested for VHE $\gamma$-ray emission, with no emission detected and upper limits on the differential flux placed at an average of 2.3% of the Crab Nebula ux. We interpret these observations in a multiwavelength context and present the most detailed $\gamma$-ray view of the region to date.

arXiv comment49 Pages, 22 Figures, 13 Tables, Accepted to ApJ

References in corpus (71)

• Astropy: A Community Python Package for Astronomy
• The Large Area Telescope on the Fermi Gamma-ray Space Telescope Mission
• The ATNF Pulsar Catalogue
• GLIMPSE: I. A SIRTF Legacy Project to Map the Inner Galaxy
• Fermi Large Area Telescope First Source Catalog
• TEMPO2, a new pulsar timing package. I: Overview
• The Second Fermi Large Area Telescope Catalog of Gamma-ray Pulsars
• Limits and Confidence Intervals in the Presence of Nuisance Parameters
• Fermi Large Area Telescope Bright Gamma-ray Source List
• The First Fermi Large Area Telescope Catalog of Gamma-ray Pulsars
• The H.E.S.S. Galactic plane survey
• Catalogue of high-mass X-ray binaries in the Galaxy ($4^{th}$ edition)
• 3FHL: The Third Catalog of Hard Fermi-LAT Sources
• Background Modelling in Very-High-Energy gamma-ray Astronomy
• A catalogue of low-mass X-ray binaries in the Galaxy, LMC, and SMC (Fourth edition)
• The 2HWC HAWC Observatory Gamma Ray Catalog
• 2FHL: The Second Catalog of Hard Fermi-LAT Sources
• The First VERITAS Telescope
• TeV Gamma-Ray Sources from a Survey of the Galactic Plane with Milagro
• The Crab Nebula and Pulsar between 500 GeV and 80 TeV: Observations with the HEGRA stereoscopic air Cherenkov telescopes
• The 1st Fermi Lat Supernova Remnant Catalog
• A Census of High-Energy Observations of Galactic Supernova Remnants
• Precise Gamma-Ray Timing and Radio Observations of 17 Fermi Gamma-Ray Pulsars
• Very High Energy Gamma-ray Radiation from the Stellar-mass Black Hole Cygnus X-1
• Spectroscopy of The Largest Ever Gamma-ray Selected BL Lac Sample
• The First Fermi-LAT Catalog of Sources Above 10 GeV
• The Trigonometric Parallax of Cygnus X-1
• Discovery of extreme particle acceleration in the microquasar Cygnus X-3
• An unidentified TeV source in the vicinity of Cygnus OB2
• The population of TeV pulsar wind nebulae in the H.E.S.S. Galactic Plane Survey
• Search for Spatially Extended Fermi-LAT Sources Using Two Years of Data
• Radio detection of LAT PSRs J1741-2054 and J2032+4127: no longer just gamma-ray pulsars
• Catalogue of particle-accelerating colliding-wind binaries
• The unidentified TeV source (TeVJ2032+4130) and surrounding field: Final HEGRA IACT-System results
• PSR J2021+4026 in the Gamma Cygni region: the first variable gamma-ray pulsar seen by the Fermi LAT
• A cut-off in the TeV gamma-ray spectrum of the SNR Cassiopeia A
• A giant radio flare from Cygnus X-3 with associated Gamma-ray emission
• Surveys with the Cherenkov Telescope Array
• MAGIC observations of the unidentified TeV gamma-ray source TeV J2032+4130
• The Einstein@Home Gamma-ray Pulsar Survey. I. Search Methods, Sensitivity and Discovery of New Young Gamma-ray Pulsars
• High-energy gamma-ray emission from Cyg X-1 measured by Fermi and its theoretical implications
• Detection of gamma rays of likely jet origin in Cygnus X-1
• Using the X-ray Dust Scattering Halo of Cygnus X-1 to determine distance and dust distributions
• Timing Gamma-ray Pulsars with the Fermi Large Area Telescope: Timing Noise and Astrometry
• Spatially Resolving the Very High Energy emission from MGRO J2019+37 with VERITAS
• Observations of the unidentified gamma-ray source TeV J2032+4130 by VERITAS
• CHANDRA/VLA Follow-up of TeV J2032+4131, the Only Unidentified TeV Gamma-ray Source
• High-energy gamma-rays from Cyg X-1
• Spectrum and Morphology of the Two Brightest Milagro Sources in the Cygnus Region: MGRO J2019+37 and MGRO J2031+41
• Magic constraints on Gamma-ray emission from Cygnus X-3
• Observation of TeV gamma rays from the Cygnus region with the ARGO-YBJ experiment
• Discovery of TeV Gamma-ray Emission Toward Supernova Remnant SNR G78.2+2.1
• The AGILE monitoring of Cygnus X-3: transient gamma-ray emission and spectral constraints
• X-ray and Radio Observations of the gamma Cygni Supernova Remnant G78.2+2.1
• Suzaku Observation of HESS J1825-137: Discovery of Largely-Extended X-rays near from PSR J1826-1334
• 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
• X-ray Observations of the Supernova Remnant CTB 87 (G74.9+1.2): An Evolved Pulsar Wind Nebula
• XMM-Newton observations of the first unidentified TeV gamma-ray source TeV J2032+4130
• The population of radio sources in the field of the unidentified gamma-ray source TeV J2032+4130
• VERITAS Observations of the Microquasar Cygnus X-3
• The GeV counterpart of VER J2019+407 in the northern shell of the supernova remnant G78.2+2.1 ($\gamma$ Cygni)
• Searches for the Shell Swept up by the Stellar Wind from Cyg OB2
• Detection of X-Ray Emission from the Unidentified TeV Gamma-Ray Source TeV J2032+4130
• The high-energy gamma-ray detection of G73.9+0.9, a supernova remnant interacting with a molecular cloud
• First bounds on the high-energy emission from isolated Wolf-Rayet binary systems
• X-ray Studies of the Extended TeV Gamma-Ray Source VER J2019+368
• Hard X-ray Emission from Sh2-104: A NuSTAR search for Gamma-ray Counterparts
• Implications of the pulsar wind nebula scenario for a TeV gamma-ray source VER J2016+371
• Pulsar Wind Nebulae and Cosmic Rays: A Bedtime Story
• Multi-wavelength study of the MGRO J2019+37

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