Fermi large area telescope observations of blazar 3C 279 occultations by the sun

Journal Article · Tue Apr 01 00:00:00 EDT 2014 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/784/2/118· OSTI ID:22357274

Barbiellini, G. ^[1]; Bastieri, D.; Buson, S. ^[2]; Bechtol, K.; Blandford, R. D.; Borgland, A. W.; Buehler, R.; Cameron, R. A.; Chiang, J. ^[3]; Bellazzini, R.; Bregeon, J. ^[4]; Bruel, P. ^[5]; Caliandro, G. A. ^[6]; Caraveo, P. A. ^[7]; Cavazzuti, E.; Ciprini, S. ^[8]; Cecchi, C. ^[9]; Chaves, R. C. G. ^[10]; Chekhtman, A. ^[11]; others, and

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1. Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, I-34127 Trieste (Italy)
2. Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131 Padova (Italy)
3. W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States)
4. Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, I-56127 Pisa (Italy)
5. Laboratoire Leprince-Ringuet, École polytechnique, CNRS/IN2P3, Palaiseau (France)
6. Institut de Ciències de l'Espai (IEEE-CSIC), Campus UAB, E-08193 Barcelona (Spain)
7. INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica, I-20133 Milano (Italy)
8. Agenzia Spaziale Italiana (ASI) Science Data Center, I-00044 Frascati (Roma) (Italy)
9. Istituto Nazionale di Fisica Nucleare, Sezione di Perugia, I-06123 Perugia (Italy)
10. Laboratoire AIM, CEA-IRFU/CNRS/Université Paris Diderot, Service d'Astrophysique, CEA Saclay, F-91191 Gif sur Yvette (France)
11. Center for Earth Observing and Space Research, College of Science, George Mason University, Fairfax, VA 22030 (United States)

Observations of occultations of bright γ-ray sources by the Sun may reveal predicted pair halos around blazars and/or new physics, such as, e.g., hypothetical light dark matter particles—axions. We use Fermi Gamma-Ray Space Telescope (Fermi) data to analyze four occultations of blazar 3C 279 by the Sun on October 8 each year from 2008 to 2011. A combined analysis of the observations of these occultations allows a point-like source at the position of 3C 279 to be detected with significance of ≈3σ, but does not reveal any significant excess over the flux expected from the quiescent Sun. The likelihood ratio test rules out complete transparency of the Sun to the blazar γ-ray emission at a 3σ confidence level.

• OSTI ID: 22357274
• Journal Information: Astrophysical Journal, Vol. 784, Issue 2; 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
AXIONS
ECLIPSE
EMISSION
GAMMA RADIATION
NONLUMINOUS MATTER
OPACITY
QUASARS
SPACE
SUN
TELESCOPES
VISIBLE RADIATION
X RADIATION