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Title: Radio-to-γ-ray monitoring of the narrow-line Seyfert 1 galaxy PMN J0948 + 0022 from 2008 to 2011

Abstract

Here, we present more than three years of observations at different frequencies, from radio to high-energy γ-rays, of the Narrow-Line Seyfert 1 (NLS1) Galaxy PMN J0948 + 0022 (z = 0.585). This source is the first NLS1 detected at energies above 100 MeV and therefore can be considered the prototype of this emerging new class of γ-ray emitting active galactic nuclei (AGN). The observations performed from 2008 August 1 to 2011 December 31 confirmed that PMN J0948 + 0022 generates a powerful relativistic jet, which is able to develop an isotropic luminosity at γ-rays of the order of 1048 erg s-1, at the level of powerful quasars. The evolution of the radiation emission of this source in 2009 and 2010 followed the canonical expectations of relativistic jets with correlated multiwavelength variability (γ-rays followed by radio emission after a few months), but it was difficult to retrieve a similar pattern in the light curves of 2011. The comparison of γ-ray spectra before and including 2011 data suggested that there was a softening of the high-energy spectral slope. We selected five specific epochs to be studied by modelling the broad-band spectrum, which are characterised by an outburst at γ-rays or very low/highmore » flux at other wavelengths. The observed variability can largely be explained by changes in the injected power, the bulk Lorentz factor of the jet, or the electron spectrum. The characteristic time scale of doubling/halving flux ranges from a few days to a few months, depending on the frequency and the sampling rate. The shortest doubling time scale at γ-rays is 2.3 ± 0.5 days. Finally, these small values underline the need of highly sampled multiwavelength campaigns to better understand the physics of these sources.« less

Authors:
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Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
Contributing Org.:
Fermi-LAT Collaboration
OSTI Identifier:
1356605
Grant/Contract Number:  
AC02-76SF00515
Resource Type:
Accepted Manuscript
Journal Name:
Astronomy and Astrophysics
Additional Journal Information:
Journal Volume: 548; Journal ID: ISSN 0004-6361
Publisher:
EDP Sciences
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; galaxies: jets; galaxies: Seyfert; gamma rays: galaxies; galaxies: individual: PMN J0948+0022

Citation Formats

Foschini, L., Angelakis, E., Fuhrmann, L., Ghisellini, G., Hovatta, T., Lahteenmaki, A., Lister, M. L., Braito, V., Gallo, L., Hamilton, T. S., Kino, M., Komossa, S., Pushkarev, A. B., Thompson, D. J., Tibolla, O., Tramacere, A., Carramiñana, A., Carrasco, L., Falcone, A., Giroletti, M., Grupe, D., Kovalev, Y. Y., Krichbaum, T. P., Max-Moerbeck, W., Nestoras, I., Pearson, T. J., Porras, A., Readhead, A. C. S., Recillas, E., Richards, J. L., Riquelme, D., Sievers, A., Tammi, J., Tornikoski, M., Ungerechts, H., Zensus, J. A., Celotti, A., Bonnoli, G., Doi, A., Maraschi, L., Tagliaferri, G., and Tavecchio, F. Radio-to-γ-ray monitoring of the narrow-line Seyfert 1 galaxy PMN J0948 + 0022 from 2008 to 2011. United States: N. p., 2012. Web. doi:10.1051/0004-6361/201220225.
Foschini, L., Angelakis, E., Fuhrmann, L., Ghisellini, G., Hovatta, T., Lahteenmaki, A., Lister, M. L., Braito, V., Gallo, L., Hamilton, T. S., Kino, M., Komossa, S., Pushkarev, A. B., Thompson, D. J., Tibolla, O., Tramacere, A., Carramiñana, A., Carrasco, L., Falcone, A., Giroletti, M., Grupe, D., Kovalev, Y. Y., Krichbaum, T. P., Max-Moerbeck, W., Nestoras, I., Pearson, T. J., Porras, A., Readhead, A. C. S., Recillas, E., Richards, J. L., Riquelme, D., Sievers, A., Tammi, J., Tornikoski, M., Ungerechts, H., Zensus, J. A., Celotti, A., Bonnoli, G., Doi, A., Maraschi, L., Tagliaferri, G., & Tavecchio, F. Radio-to-γ-ray monitoring of the narrow-line Seyfert 1 galaxy PMN J0948 + 0022 from 2008 to 2011. United States. doi:10.1051/0004-6361/201220225.
Foschini, L., Angelakis, E., Fuhrmann, L., Ghisellini, G., Hovatta, T., Lahteenmaki, A., Lister, M. L., Braito, V., Gallo, L., Hamilton, T. S., Kino, M., Komossa, S., Pushkarev, A. B., Thompson, D. J., Tibolla, O., Tramacere, A., Carramiñana, A., Carrasco, L., Falcone, A., Giroletti, M., Grupe, D., Kovalev, Y. Y., Krichbaum, T. P., Max-Moerbeck, W., Nestoras, I., Pearson, T. J., Porras, A., Readhead, A. C. S., Recillas, E., Richards, J. L., Riquelme, D., Sievers, A., Tammi, J., Tornikoski, M., Ungerechts, H., Zensus, J. A., Celotti, A., Bonnoli, G., Doi, A., Maraschi, L., Tagliaferri, G., and Tavecchio, F. Fri . "Radio-to-γ-ray monitoring of the narrow-line Seyfert 1 galaxy PMN J0948 + 0022 from 2008 to 2011". United States. doi:10.1051/0004-6361/201220225. https://www.osti.gov/servlets/purl/1356605.
@article{osti_1356605,
title = {Radio-to-γ-ray monitoring of the narrow-line Seyfert 1 galaxy PMN J0948 + 0022 from 2008 to 2011},
author = {Foschini, L. and Angelakis, E. and Fuhrmann, L. and Ghisellini, G. and Hovatta, T. and Lahteenmaki, A. and Lister, M. L. and Braito, V. and Gallo, L. and Hamilton, T. S. and Kino, M. and Komossa, S. and Pushkarev, A. B. and Thompson, D. J. and Tibolla, O. and Tramacere, A. and Carramiñana, A. and Carrasco, L. and Falcone, A. and Giroletti, M. and Grupe, D. and Kovalev, Y. Y. and Krichbaum, T. P. and Max-Moerbeck, W. and Nestoras, I. and Pearson, T. J. and Porras, A. and Readhead, A. C. S. and Recillas, E. and Richards, J. L. and Riquelme, D. and Sievers, A. and Tammi, J. and Tornikoski, M. and Ungerechts, H. and Zensus, J. A. and Celotti, A. and Bonnoli, G. and Doi, A. and Maraschi, L. and Tagliaferri, G. and Tavecchio, F.},
abstractNote = {Here, we present more than three years of observations at different frequencies, from radio to high-energy γ-rays, of the Narrow-Line Seyfert 1 (NLS1) Galaxy PMN J0948 + 0022 (z = 0.585). This source is the first NLS1 detected at energies above 100 MeV and therefore can be considered the prototype of this emerging new class of γ-ray emitting active galactic nuclei (AGN). The observations performed from 2008 August 1 to 2011 December 31 confirmed that PMN J0948 + 0022 generates a powerful relativistic jet, which is able to develop an isotropic luminosity at γ-rays of the order of 1048 erg s-1, at the level of powerful quasars. The evolution of the radiation emission of this source in 2009 and 2010 followed the canonical expectations of relativistic jets with correlated multiwavelength variability (γ-rays followed by radio emission after a few months), but it was difficult to retrieve a similar pattern in the light curves of 2011. The comparison of γ-ray spectra before and including 2011 data suggested that there was a softening of the high-energy spectral slope. We selected five specific epochs to be studied by modelling the broad-band spectrum, which are characterised by an outburst at γ-rays or very low/high flux at other wavelengths. The observed variability can largely be explained by changes in the injected power, the bulk Lorentz factor of the jet, or the electron spectrum. The characteristic time scale of doubling/halving flux ranges from a few days to a few months, depending on the frequency and the sampling rate. The shortest doubling time scale at γ-rays is 2.3 ± 0.5 days. Finally, these small values underline the need of highly sampled multiwavelength campaigns to better understand the physics of these sources.},
doi = {10.1051/0004-6361/201220225},
journal = {Astronomy and Astrophysics},
number = ,
volume = 548,
place = {United States},
year = {2012},
month = {11}
}

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Works referenced in this record:

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Accretion and jet power in active galactic nuclei
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FERMI /LARGE AREA TELESCOPE DISCOVERY OF GAMMA-RAY EMISSION FROM A RELATIVISTIC JET IN THE NARROW-LINE QUASAR PMN J0948+0022
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FERMI LARGE AREA TELESCOPE SECOND SOURCE CATALOG
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Spectropolarimetry of 'narrow-line' Seyfert 1 galaxies
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Signatures of synchrotron emission and of electron acceleration in the X-ray spectra of Mrk 421
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Photometric calibration of the Swift ultraviolet/optical telescope: Photometric calibration of the Swift UVOT
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GAMMA-RAY LIGHT CURVES AND VARIABILITY OF BRIGHT FERMI -DETECTED BLAZARS
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General physical properties of bright Fermi blazars: Properties of bright Fermi blazars
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The first gamma-ray outburst of a narrow-line Seyfert 1 galaxy: the case of PMN J0948+0022 in 2010 July: First γ-ray outburst of a NLS1
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γ-Ray and Parsec-Scale jet Properties of a Complete Sample of Blazars from the Mojave Program
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Parameter estimation in astronomy through application of the likelihood ratio
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Radio-Loud Narrow-Line Seyfert 1 as a new Class of Gamma-Ray Active Galactic Nuclei
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Multiwavelength Monitoring of the Enigmatic Narrow-Line Seyfert 1 pmn J0948+0022 in 2009 March-July
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Radio properties of narrow-lined Seyfert 1 galaxies
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The Burst Alert Telescope (BAT) on the SWIFT Midex Mission
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Narrow-line Seyfert 1 Galaxies from the Sloan Digital Sky Survey Early Data Release
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    Works referencing / citing this record:

    General physical properties of bright Fermi blazars: Properties of bright Fermi blazars
    journal, November 2009


    The Likelihood Analysis of EGRET Data
    journal, April 1996

    • Mattox, J. R.; Bertsch, D. L.; Chiang, J.
    • The Astrophysical Journal, Vol. 461
    • DOI: 10.1086/177068

    SDSS J094857.3+002225: A Very Radio Loud, Narrow‐Line Quasar with Relativistic Jets?
    journal, February 2003

    • Zhou, Hong‐Yan; Wang, Ting‐Gui; Dong, Xiao‐Bo
    • The Astrophysical Journal, Vol. 584, Issue 1
    • DOI: 10.1086/345523

    The Leiden/Argentine/Bonn (LAB) Survey of Galactic HI: Final data release of the combined LDS and IAR surveys with improved stray-radiation corrections
    journal, September 2005


    A Population of Radio‐Loud Narrow‐Line Seyfert 1 Galaxies with Blazar‐Like Properties?
    journal, October 2008

    • Yuan, W.; Zhou, H. Y.; Komossa, S.
    • The Astrophysical Journal, Vol. 685, Issue 2
    • DOI: 10.1086/591046

    Optical polarisation variability of radio-loud narrow-line Seyfert 1 galaxies: Search for long rotations of the polarisation plane
    journal, October 2018


    MOJAVE: Monitoring of Jets in Active Galactic Nuclei with VLBA Experiments. I. First-Epoch 15 GHz Linear Polarization Images
    journal, October 2005

    • Lister, M. L.; Homan, D. C.
    • The Astronomical Journal, Vol. 130, Issue 4
    • DOI: 10.1086/432969

    The first gamma-ray outburst of a narrow-line Seyfert 1 galaxy: the case of PMN J0948+0022 in 2010 July: First γ-ray outburst of a NLS1
    journal, March 2011


    Search for the shortest variability at gamma rays in flat-spectrum radio quasars
    journal, May 2011


    Photopolarimetric Monitoring of Blazars in the Optical and Near-Infrared Bands with the Kanata Telescope. I. Correlations between Flux, Color, and Polarization
    journal, June 2011

    • Ikejiri, Yuki; Uemura, Makoto; Sasada, Mahito
    • Publications of the Astronomical Society of Japan, Vol. 63, Issue 3
    • DOI: 10.1093/pasj/63.3.327

    Radio jet emission from GeV-emitting narrow-line Seyfert 1 galaxies
    journal, February 2015


    FERMI /LARGE AREA TELESCOPE DISCOVERY OF GAMMA-RAY EMISSION FROM A RELATIVISTIC JET IN THE NARROW-LINE QUASAR PMN J0948+0022
    journal, June 2009


    Maximum Brightness Temperature of an Incoherent Synchrotron Source : Inverse Compton Limit—A Misnomer
    journal, September 2009


    Parameter estimation in astronomy through application of the likelihood ratio
    journal, March 1979


    Multiwavelength Observations of Strong Flares from the TeV Blazar 1ES 1959+650
    journal, January 2004

    • Krawczynski, H.; Hughes, S. B.; Horan, D.
    • The Astrophysical Journal, Vol. 601, Issue 1
    • DOI: 10.1086/380393

    The Palermo Swift -BAT hard X-ray catalogue : III. Results after 54 months of sky survey⋆
    journal, November 2010


    The spectra of narrow-line Seyfert 1 galaxies
    journal, October 1985

    • Osterbrock, D. E.; Pogge, R. W.
    • The Astrophysical Journal, Vol. 297
    • DOI: 10.1086/163513

    FERMI LARGE AREA TELESCOPE SECOND SOURCE CATALOG
    journal, March 2012

    • Nolan, P. L.; Abdo, A. A.; Ackermann, M.
    • The Astrophysical Journal Supplement Series, Vol. 199, Issue 2
    • DOI: 10.1088/0067-0049/199/2/31

    The Swift X-Ray Telescope
    journal, October 2005


    Powerful Relativistic jets in Spiral Galaxies
    journal, January 2012


    The inverse Compton catastrophe and high brightness temperature radio sources
    journal, November 2006


    Narrow-line Seyfert 1 Galaxies from the Sloan Digital Sky Survey Early Data Release
    journal, December 2002

    • Williams, Rik J.; Pogge, Richard W.; Mathur, Smita
    • The Astronomical Journal, Vol. 124, Issue 6
    • DOI: 10.1086/344765

    The non-linear dependence of flux on black hole mass and accretion rate in core-dominated jets
    journal, August 2003


    Readout modes and automated operation of the Swift X-ray Telescope
    conference, February 2004

    • Hill, Joanne E.; Burrows, David N.; Nousek, John A.
    • Optical Science and Technology, SPIE's 48th Annual Meeting, SPIE Proceedings
    • DOI: 10.1117/12.505728

    Studies in astronomical time series analysis. I - Modeling random processes in the time domain
    journal, January 1981

    • Scargle, J. D.
    • The Astrophysical Journal Supplement Series, Vol. 45
    • DOI: 10.1086/190706

    Radio properties of narrow-lined Seyfert 1 galaxies
    journal, January 1995

    • Ulvestad, James S.; Antonucci, Robert R. J.; Goodrich, Robert W.
    • The Astronomical Journal, Vol. 109
    • DOI: 10.1086/117258

    Radio-loud Narrow-Line Type 1 Quasars
    journal, June 2006

    • Komossa, Stefanie; Voges, Wolfgang; Xu, Dawei
    • The Astronomical Journal, Vol. 132, Issue 2
    • DOI: 10.1086/505043

    Spectropolarimetry of 'narrow-line' Seyfert 1 galaxies
    journal, July 1989

    • Goodrich, Robert W.
    • The Astrophysical Journal, Vol. 342
    • DOI: 10.1086/167586

    Mojave: Monitoring of jets in Active Galactic Nuclei with vlba Experiments. v. Multi-Epoch vlba Images
    journal, February 2009


    The relationship between infrared, optical, and ultraviolet extinction
    journal, October 1989

    • Cardelli, Jason A.; Clayton, Geoffrey C.; Mathis, John S.
    • The Astrophysical Journal, Vol. 345
    • DOI: 10.1086/167900

    BLAZARS IN THE FERMI ERA: THE OVRO 40 m TELESCOPE MONITORING PROGRAM
    journal, May 2011

    • Richards, Joseph L.; Max-Moerbeck, Walter; Pavlidou, Vasiliki
    • The Astrophysical Journal Supplement Series, Vol. 194, Issue 2
    • DOI: 10.1088/0067-0049/194/2/29

    Relativistic jets as compact radio sources
    journal, August 1979

    • Blandford, R. D.; Konigl, A.
    • The Astrophysical Journal, Vol. 232
    • DOI: 10.1086/157262

    Violent Intranight Optical Variability of a Radio-Loud Narrow-Line Seyfert 1 Galaxy: sdss J094857.3+002225
    journal, May 2010


    VLBI Observations of the Most Radio-Loud, Narrow-Line Quasar SDSS J094857.3 + 002225
    journal, October 2006

    • Doi, Akihiro; Nagai, Hiroshi; Asada, Keiichi
    • Publications of the Astronomical Society of Japan, Vol. 58, Issue 5
    • DOI: 10.1093/pasj/58.5.829

    Smarts Optical and Infrared Monitoring of 12 Gamma-Ray Bright Blazars
    journal, August 2012


    Intraday Variability in Quasars and BL LAC Objects
    journal, September 1995


    The Burst Alert Telescope (BAT) on the SWIFT Midex Mission
    journal, October 2005

    • Barthelmy, Scott D.; Barbier, Louis M.; Cummings, Jay R.
    • Space Science Reviews, Vol. 120, Issue 3-4
    • DOI: 10.1007/s11214-005-5096-3

    Signatures of synchrotron emission and of electron acceleration in the X-ray spectra of Mrk 421
    journal, February 2007


    SEVEN-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE ( WMAP ) OBSERVATIONS: COSMOLOGICAL INTERPRETATION
    journal, January 2011

    • Komatsu, E.; Smith, K. M.; Dunkley, J.
    • The Astrophysical Journal Supplement Series, Vol. 192, Issue 2
    • DOI: 10.1088/0067-0049/192/2/18

    FERMI LARGE AREA TELESCOPE FIRST SOURCE CATALOG
    journal, May 2010

    • Abdo, A. A.; Ackermann, M.; Ajello, M.
    • The Astrophysical Journal Supplement Series, Vol. 188, Issue 2
    • DOI: 10.1088/0067-0049/188/2/405

    Radio-Loud Narrow-Line Seyfert 1 as a new Class of Gamma-Ray Active Galactic Nuclei
    journal, December 2009


    Accretion and jet power in active galactic nuclei
    journal, October 2011


    Multiwavelength Monitoring of the Enigmatic Narrow-Line Seyfert 1 pmn J0948+0022 in 2009 March-July
    journal, November 2009


    γ-Ray and Parsec-Scale jet Properties of a Complete Sample of Blazars from the Mojave Program
    journal, November 2011


    Photometric calibration of the Swift ultraviolet/optical telescope: Photometric calibration of the Swift UVOT
    journal, December 2007


    Fifteen years monitoring of extragalactic radio sources at 22, 37 and 87 GHz
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