Abstract
We present results from deep observations toward the Cygnus region using 300 hr of very high energy (VHE) γ-ray data taken with the VERITAS Cerenkov telescope array and over 7 yr of high-energy γ-ray data taken with the Fermi satellite at an energy above 1 GeV. As the brightest region of diffuse γ-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 J2021.0+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 γ-ray emission, with no emission detected and upper limits on the differential flux placed at an average of 2.3% of the Crab Nebula flux. We interpret these observations in a multiwavelength context and present the most detailed γ-ray view of the region to date.
| Original language | English |
|---|---|
| Article number | 134 |
| Journal | Astrophysical Journal |
| Volume | 861 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 10 Jul 2018 |
Keywords
- ISM: supernova remnants
- acceleration of particles
- cosmic rays
- gamma rays: general
Authors (Note for portal: view the doc link for the full list of authors)
- Authors
- Abeysekara, AU,Archer, A,Aune, T,Benbow, W,Bird, R,Brose, R,Buchovecky, M,Bugaev, V,Cui, W,Daniel, MK,Falcone, A,Feng, Q,Finley, JP,Fleischhack, H,Flinders, A,Fortson, L,Furniss, A,Gotthelf, EV,Grube, J,Hanna, D,Hervet, O,Holder, J,Huang, K,Hughes, G,Humensky, TB,Hutten, M,Johnson, CA,Kaaret, P,Kar, P,Kelley-Hoskins, N,Kertzman, M,Kieda, D,Krause, M,Kumar, S,Lang, MJ,Lin, TTY,Maier, G,McArthur, S,Moriarty, P,Mukherjee, R,O'Brien, S,Ong, RA,Otte, AN,Pandel, D,Park, N,Petrashyk, A,Pohl, M,Popkow, A,Pueschel, E,Quinn, J,Ragan, K,Reynolds, PT,Richards, GT,Roache, E,Rousselle, J,Rulten, C,Sadeh, I,Santander, M,Sembroski, GH,Shahinyan, K,Tyler, J,Vassiliev, VV,Wakely, SP,Ward, JE,Weinstein, A,Wells, RM,Wilcox, P,Wilhelm, A,Williams, DA,Zitzer, B