Spatially resolving the very high energy emission from MGRO J2019+37 with VERITAS

Journal Article · Tue Jun 10 00:00:00 EDT 2014 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/788/1/78· OSTI ID:22356639

Aliu, E.; Errando, M. ^[1]; Aune, T. ^[2]; Behera, B.; Chen, X.; Federici, S. ^[3]; Beilicke, M.; Buckley, J. H.; Bugaev, V. ^[4]; Benbow, W.; Cerruti, M. ^[5]; Berger, K. ^[6]; Bird, R. ^[7]; Bouvier, A. ^[8]; Ciupik, L. ^[9]; Connolly, M. P. ^[10]; Cui, W. ^[11]; Dumm, J. ^[12]; Dwarkadas, V. V. ^[13]; others, and

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1. Department of Physics and Astronomy, Barnard College, Columbia University, NY 10027 (United States)
2. Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States)
3. DESY, Platanenallee 6, D-15738 Zeuthen (Germany)
4. Department of Physics, Washington University, St. Louis, MO 63130 (United States)
5. Fred Lawrence Whipple Observatory, Harvard-Smithsonian Center for Astrophysics, Amado, AZ 85645 (United States)
6. Department of Physics and Astronomy and the Bartol Research Institute, University of Delaware, Newark, DE 19716 (United States)
7. School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland)
8. Santa Cruz Institute for Particle Physics and Department of Physics, University of California, Santa Cruz, CA 95064 (United States)
9. Astronomy Department, Adler Planetarium and Astronomy Museum, Chicago, IL 60605 (United States)
10. School of Physics, National University of Ireland Galway, University Road, Galway (Ireland)
11. Department of Physics, Purdue University, West Lafayette, IN 47907 (United States)
12. School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)
13. Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States)

We present very high energy (VHE) imaging of MGRO J2019+37 obtained with the VERITAS observatory. The bright extended (∼2°) unidentified Milagro source is located toward the rich star formation region Cygnus-X. MGRO J2019+37 is resolved into two VERITAS sources. The faint, point-like source VER J2016+371 overlaps CTB 87, a filled-center remnant (SNR) with no evidence of a supernova remnant shell at the present time. Its spectrum is well fit in the 0.65-10 TeV energy range by a power-law model with photon index 2.3 ± 0.4. VER J2019+378 is a bright extended (∼1°) source that likely accounts for the bulk of the Milagro emission and is notably coincident with PSR J2021+3651 and the star formation region Sh 2–104. Its spectrum in the range 1-30 TeV is well fit with a power-law model of photon index 1.75 ± 0.3, among the hardest values measured in the VHE band, comparable to that observed near Vela-X. We explore the unusual spectrum and morphology in the radio and X-ray bands to constrain possible emission mechanisms for this source.

• OSTI ID: 22356639
• Journal Information: Astrophysical Journal, Vol. 788, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
COMPARATIVE EVALUATIONS
EMISSION
GAMMA RADIATION
PHOTONS
PULSARS
SPECTRA
SUPERNOVA REMNANTS
SUPERNOVAE
TEV RANGE
X RADIATION