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Title: NuSTAR, Swift, and GROND Observations of the Flaring MeV Blazar PMN J0641�

Authors:
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Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC); National Aeronautics and Space Administration (NASA)
OSTI Identifier:
1313951
Report Number(s):
SLAC-PUB-16791
Journal ID: ISSN 1538-4357; arXiv:1602.06446
DOE Contract Number:
AC02-76SF00515
Resource Type:
Journal Article
Resource Relation:
Journal Name: The Astrophysical Journal (Online); Journal Volume: 826; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
Astrophysics,ASTRO, GRQC

Citation Formats

Ajello, M., /Clemson U., Ghisellini, G., /Brera Observ., Paliya, V.S., /Clemson U. /Bangalore, Indian Inst. Astrophys., Kocevski, D., /NASA, Goddard, Tagliaferri, G., /Brera Observ., Madejski, G., /KIPAC, Menlo Park, Rau, A., Schady, P., Greiner, J., /Garching, Max Planck Inst., MPE, Massaro, F., /Turin U., Bakolovic, M., /Caltech, Buehler, R., Giomi, M., /DESY, Zeuthen, Marcotulli, L., /Clemson U., D'Ammando, F., /INAF-IRA, Bologna /Bologna U., Dept. Astron., Stern, D., /Caltech, JPL, Boggs, S.E., /UC, Berkeley, Space Sci. Dept., Christensen, F.E., /Danish Space Res. Inst., Craig, W.W., /Danish Space Res. Inst. /LLNL, Livermore, Hailey, C.J., /Columbia U., Harrison, F.A., and /Caltech. /NASA, Goddard. NuSTAR, Swift, and GROND Observations of the Flaring MeV Blazar PMN J0641�. United States: N. p., 2016. Web. doi:10.3847/0004-637X/826/1/76.
Ajello, M., /Clemson U., Ghisellini, G., /Brera Observ., Paliya, V.S., /Clemson U. /Bangalore, Indian Inst. Astrophys., Kocevski, D., /NASA, Goddard, Tagliaferri, G., /Brera Observ., Madejski, G., /KIPAC, Menlo Park, Rau, A., Schady, P., Greiner, J., /Garching, Max Planck Inst., MPE, Massaro, F., /Turin U., Bakolovic, M., /Caltech, Buehler, R., Giomi, M., /DESY, Zeuthen, Marcotulli, L., /Clemson U., D'Ammando, F., /INAF-IRA, Bologna /Bologna U., Dept. Astron., Stern, D., /Caltech, JPL, Boggs, S.E., /UC, Berkeley, Space Sci. Dept., Christensen, F.E., /Danish Space Res. Inst., Craig, W.W., /Danish Space Res. Inst. /LLNL, Livermore, Hailey, C.J., /Columbia U., Harrison, F.A., & /Caltech. /NASA, Goddard. NuSTAR, Swift, and GROND Observations of the Flaring MeV Blazar PMN J0641�. United States. doi:10.3847/0004-637X/826/1/76.
Ajello, M., /Clemson U., Ghisellini, G., /Brera Observ., Paliya, V.S., /Clemson U. /Bangalore, Indian Inst. Astrophys., Kocevski, D., /NASA, Goddard, Tagliaferri, G., /Brera Observ., Madejski, G., /KIPAC, Menlo Park, Rau, A., Schady, P., Greiner, J., /Garching, Max Planck Inst., MPE, Massaro, F., /Turin U., Bakolovic, M., /Caltech, Buehler, R., Giomi, M., /DESY, Zeuthen, Marcotulli, L., /Clemson U., D'Ammando, F., /INAF-IRA, Bologna /Bologna U., Dept. Astron., Stern, D., /Caltech, JPL, Boggs, S.E., /UC, Berkeley, Space Sci. Dept., Christensen, F.E., /Danish Space Res. Inst., Craig, W.W., /Danish Space Res. Inst. /LLNL, Livermore, Hailey, C.J., /Columbia U., Harrison, F.A., and /Caltech. /NASA, Goddard. 2016. "NuSTAR, Swift, and GROND Observations of the Flaring MeV Blazar PMN J0641�". United States. doi:10.3847/0004-637X/826/1/76. https://www.osti.gov/servlets/purl/1313951.
@article{osti_1313951,
title = {NuSTAR, Swift, and GROND Observations of the Flaring MeV Blazar PMN J0641�},
author = {Ajello, M. and /Clemson U. and Ghisellini, G. and /Brera Observ. and Paliya, V.S. and /Clemson U. /Bangalore, Indian Inst. Astrophys. and Kocevski, D. and /NASA, Goddard and Tagliaferri, G. and /Brera Observ. and Madejski, G. and /KIPAC, Menlo Park and Rau, A. and Schady, P. and Greiner, J. and /Garching, Max Planck Inst., MPE and Massaro, F. and /Turin U. and Bakolovic, M. and /Caltech and Buehler, R. and Giomi, M. and /DESY, Zeuthen and Marcotulli, L. and /Clemson U. and D'Ammando, F. and /INAF-IRA, Bologna /Bologna U., Dept. Astron. and Stern, D. and /Caltech, JPL and Boggs, S.E. and /UC, Berkeley, Space Sci. Dept. and Christensen, F.E. and /Danish Space Res. Inst. and Craig, W.W. and /Danish Space Res. Inst. /LLNL, Livermore and Hailey, C.J. and /Columbia U. and Harrison, F.A. and /Caltech. /NASA, Goddard},
abstractNote = {},
doi = {10.3847/0004-637X/826/1/76},
journal = {The Astrophysical Journal (Online)},
number = 1,
volume = 826,
place = {United States},
year = 2016,
month = 8
}
  • Here we report the results of a multiband observing campaign on the famous blazar 3C 279 conducted during a phase of increased activity from 2013 December to 2014 April, including first observations of it with NuSTAR. The γ-ray emission of the source measured by Fermi-LAT showed multiple distinct flares reaching the highest flux level measured in this object since the beginning of the Fermi mission, with F(E>100 MeV) of 10 -5 photons cm -2 s -1, and with a flux-doubling time scale as short as 2 hr. The γ-ray spectrum during one of the flares was very hard, with an index of Γ γ =1.7±0.1, which is rarely seen in flat-spectrum radio quasars. The lack of concurrent optical variability implies a very high Compton dominance parameter L γ/L syn > 300. Two 1 day NuSTAR observations with accompanying Swift pointings were separated by 2 weeks, probing different levels of source activity. While the 0.5-70 keV X-ray spectrum obtained during the first pointing, and fitted jointly with Swift-XRT is well-described by a simple power law, the second joint observation showed an unusual spectral structure: the spectrum softens by ΔΓ xmore » $$\simeq$$ 0.4 at ~ keV. Modeling the broadband spectral energy distribution during this flare with the standard synchrotron plus inverse-Compton model requires: (1) the location of the γ-ray emitting region is comparable with the broad-line region radius, (2) a very hard electron energy distribution index p $$\simeq$$ 1, (3) total jet power significantly exceeding the accretion-disk luminosity L j/L d ≳ 10, and (4) extremely low jet magnetization with L B/L j ≲ 10 -4. In conclusion, we also find that single-zone models that match the observed γ-ray and optical spectra cannot satisfactorily explain the production of X-ray emission.« less
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