Artículos de revistas
Multiwavelength Observations and Modeling of 1ES 1959+650 in a Low Flux State
Fecha
2013-09-20Registro en:
Aliu, E.; Archambault, S.; Arlen, T.; Aune, T.; Beilicke, M.; et al.; Multiwavelength Observations and Modeling of 1ES 1959+650 in a Low Flux State; Iop Publishing Ltd; Astrophysical Journal; 775; 3; 20-9-2013; 1-8
0004-637X
Autor
Aliu, E.
Archambault, S.
Arlen, T.
Aune, T.
Beilicke, M.
Benbow, W.
Bird, R.
Bottcher, M.
Bouvier, A.
Bugaev, V.
Byrum, K.
Cesarini, A.
Ciupik, L.
Collins-Hughes, E.
Connolly, M. P.
Cui, W.
Dickherber, R.
Duke, C.
Dumm, J.
Errando, M.
Falcone, A.
Federici, S.
Feng, Q.
Finley, J. P.
Finnegan, G.
Fortson, L.
Furniss, A.
Galante, N.
Gall, D.
Pichel, Ana Carolina
Resumen
We report on the VERITAS observations of the high-frequency peaked BL Lac object 1ES 1959+650 in the period 2007–2011. This source is detected at TeV energies by VERITAS at 16.4 standard deviation (σ) significance in 7.6 hr of observation in a low flux state. A multiwavelength spectral energy distribution (SED) is constructed from contemporaneous data from VERITAS, Fermi-LAT, RXTE PCA, and Swift UVOT. Swift XRT data is not included in the SED due to a lack of simultaneous observations with VERITAS. In contrast to the orphan γ -ray flare exhibited by this source in 2002, the X-ray flux of the source is found to vary by an order of magnitude, while other energy regimes exhibit less variable emission. A quasi-equilibrium synchrotron self-Compton model with an additional external radiation field is used to describe three SEDs corresponding to the lowest, highest, and average X-ray states. The variation in the X-ray spectrum is modeled by changing the electron injection spectral index, with minor adjustments of the kinetic luminosity in electrons. This scenario produces small-scale flux variability of the order of 2 in the high energy (E > 1 MeV) and very high energy (E > 100 GeV) γ -ray regimes, which is corroborated by the Fermi-LAT, VERITAS, and Whipple 10 m telescope light curves.