Multiwavelength observations of the blazar markarian 421 in 2002 December and 2003 January

P. F. Rebillot, H. M. Badran, G. Blaylock, S. M. Bradbury, J. H. Buckley, D. A. Carter-Lewis, O. Celik, Y. C. Chow, P. Cogan, W. Cui, M. Daniel, C. Duke, A. Falcone, S. J. Fegan, J. P. Finley, L. F. Fortson, G. H. Gillanders, J. Grube, K. Gutierrez, G. GyukD. Hanna, J. Holder, D. Horan, S. B. Hughes, G. E. Kenny, M. Kertzman, D. Kieda, J. Kildea, K. Kosack, H. Krawczynski, F. Krennrich, M. J. Lang, S. Le Bohec, E. Linton, G. Maier, P. Moriarty, J. Perkins, M. Pohl, J. Quinn, K. Ragan, P. T. Reynolds, H. J. Rose, M. Schroedter, G. H. Sembroski, G. Steele, S. P. Swordy, L. Valcarcel, V. V. Vassilev, S. P. Wakely, T. C. Weekes, J. Zweerink, M. Aller, H. Aller, P. Boltwood, I. Jung, D. Kranich, K. Nilsson, M. Pasanen, A. Sadun, A. Sillanpaa

Research output: Contribution to journalArticle

44 Citations (Scopus)

Abstract

We report on a multiwavelength campaign on the TeV γ-ray blazar Mrk 421 performed during 2002 December and 2003 January. These target of opportunity observations were initiated by the detection of X-ray and TeV γ-ray flares with the All Sky Monitor (ASM) on board the RossiX-Ray Timing Explorer (RXTE) and the 10 m Whipple γ-ray telescope. The campaign included observational coverage in the radio (University of Michigan Radio Astronomy Observatory), optical (Boltwood, La Palma KVA 0.6 m; WIYN 0.9 m), X-ray (RXTE pointed telescopes), and TeV γ-ray (Whipple and HEGRA) bands. At TeV energies, the observations revealed several flares at intermediate flux levels, peaking between 1 and 1.5 times the flux from the Crab Nebula. While the time-averaged spectrum can be fitted with a single power law of photon index Γ = 2.8 from dNγ/dE ∝ E, we find some evidence for spectral variability. Confirming earlier results, the campaign reveals a rather loose correlation between the X-ray and TeV γ-ray fluxes. In one case, a very strong X-ray flare is not accompanied by a comparable TeV γ-ray flare. Although the source flux was variable in the optical and radio bands, the sparse sampling of the optical and radio light curves does not allow us to study the correlation properties in detail. We present a simple analysis of the data with a synchrotron self-Compton model, emphasizing that models with very high Doppler factors and low magnetic fields can describe the data.

Original languageEnglish (US)
Pages (from-to)740-751
Number of pages12
JournalAstrophysical Journal
Volume641
Issue number2 I
DOIs
StatePublished - Apr 20 2006

Fingerprint

rays
radio
flares
astronomy
crab
power law
x rays
observatory
time measurement
telescopes
magnetic field
Crab nebula
radio astronomy
sampling
light curve
energy
sky
monitors
observatories
synchrotrons

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Rebillot, P. F., Badran, H. M., Blaylock, G., Bradbury, S. M., Buckley, J. H., Carter-Lewis, D. A., ... Sillanpaa, A. (2006). Multiwavelength observations of the blazar markarian 421 in 2002 December and 2003 January. Astrophysical Journal, 641(2 I), 740-751. https://doi.org/10.1086/500653
Rebillot, P. F. ; Badran, H. M. ; Blaylock, G. ; Bradbury, S. M. ; Buckley, J. H. ; Carter-Lewis, D. A. ; Celik, O. ; Chow, Y. C. ; Cogan, P. ; Cui, W. ; Daniel, M. ; Duke, C. ; Falcone, A. ; Fegan, S. J. ; Finley, J. P. ; Fortson, L. F. ; Gillanders, G. H. ; Grube, J. ; Gutierrez, K. ; Gyuk, G. ; Hanna, D. ; Holder, J. ; Horan, D. ; Hughes, S. B. ; Kenny, G. E. ; Kertzman, M. ; Kieda, D. ; Kildea, J. ; Kosack, K. ; Krawczynski, H. ; Krennrich, F. ; Lang, M. J. ; Le Bohec, S. ; Linton, E. ; Maier, G. ; Moriarty, P. ; Perkins, J. ; Pohl, M. ; Quinn, J. ; Ragan, K. ; Reynolds, P. T. ; Rose, H. J. ; Schroedter, M. ; Sembroski, G. H. ; Steele, G. ; Swordy, S. P. ; Valcarcel, L. ; Vassilev, V. V. ; Wakely, S. P. ; Weekes, T. C. ; Zweerink, J. ; Aller, M. ; Aller, H. ; Boltwood, P. ; Jung, I. ; Kranich, D. ; Nilsson, K. ; Pasanen, M. ; Sadun, A. ; Sillanpaa, A. / Multiwavelength observations of the blazar markarian 421 in 2002 December and 2003 January. In: Astrophysical Journal. 2006 ; Vol. 641, No. 2 I. pp. 740-751.
@article{c75d5304a91c4b5cb135ddbec0814f80,
title = "Multiwavelength observations of the blazar markarian 421 in 2002 December and 2003 January",
abstract = "We report on a multiwavelength campaign on the TeV γ-ray blazar Mrk 421 performed during 2002 December and 2003 January. These target of opportunity observations were initiated by the detection of X-ray and TeV γ-ray flares with the All Sky Monitor (ASM) on board the RossiX-Ray Timing Explorer (RXTE) and the 10 m Whipple γ-ray telescope. The campaign included observational coverage in the radio (University of Michigan Radio Astronomy Observatory), optical (Boltwood, La Palma KVA 0.6 m; WIYN 0.9 m), X-ray (RXTE pointed telescopes), and TeV γ-ray (Whipple and HEGRA) bands. At TeV energies, the observations revealed several flares at intermediate flux levels, peaking between 1 and 1.5 times the flux from the Crab Nebula. While the time-averaged spectrum can be fitted with a single power law of photon index Γ = 2.8 from dNγ/dE ∝ E-Γ, we find some evidence for spectral variability. Confirming earlier results, the campaign reveals a rather loose correlation between the X-ray and TeV γ-ray fluxes. In one case, a very strong X-ray flare is not accompanied by a comparable TeV γ-ray flare. Although the source flux was variable in the optical and radio bands, the sparse sampling of the optical and radio light curves does not allow us to study the correlation properties in detail. We present a simple analysis of the data with a synchrotron self-Compton model, emphasizing that models with very high Doppler factors and low magnetic fields can describe the data.",
author = "Rebillot, {P. F.} and Badran, {H. M.} and G. Blaylock and Bradbury, {S. M.} and Buckley, {J. H.} and Carter-Lewis, {D. A.} and O. Celik and Chow, {Y. C.} and P. Cogan and W. Cui and M. Daniel and C. Duke and A. Falcone and Fegan, {S. J.} and Finley, {J. P.} and Fortson, {L. F.} and Gillanders, {G. H.} and J. Grube and K. Gutierrez and G. Gyuk and D. Hanna and J. Holder and D. Horan and Hughes, {S. B.} and Kenny, {G. E.} and M. Kertzman and D. Kieda and J. Kildea and K. Kosack and H. Krawczynski and F. Krennrich and Lang, {M. J.} and {Le Bohec}, S. and E. Linton and G. Maier and P. Moriarty and J. Perkins and M. Pohl and J. Quinn and K. Ragan and Reynolds, {P. T.} and Rose, {H. J.} and M. Schroedter and Sembroski, {G. H.} and G. Steele and Swordy, {S. P.} and L. Valcarcel and Vassilev, {V. V.} and Wakely, {S. P.} and Weekes, {T. C.} and J. Zweerink and M. Aller and H. Aller and P. Boltwood and I. Jung and D. Kranich and K. Nilsson and M. Pasanen and A. Sadun and A. Sillanpaa",
year = "2006",
month = "4",
day = "20",
doi = "10.1086/500653",
language = "English (US)",
volume = "641",
pages = "740--751",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "2 I",

}

Rebillot, PF, Badran, HM, Blaylock, G, Bradbury, SM, Buckley, JH, Carter-Lewis, DA, Celik, O, Chow, YC, Cogan, P, Cui, W, Daniel, M, Duke, C, Falcone, A, Fegan, SJ, Finley, JP, Fortson, LF, Gillanders, GH, Grube, J, Gutierrez, K, Gyuk, G, Hanna, D, Holder, J, Horan, D, Hughes, SB, Kenny, GE, Kertzman, M, Kieda, D, Kildea, J, Kosack, K, Krawczynski, H, Krennrich, F, Lang, MJ, Le Bohec, S, Linton, E, Maier, G, Moriarty, P, Perkins, J, Pohl, M, Quinn, J, Ragan, K, Reynolds, PT, Rose, HJ, Schroedter, M, Sembroski, GH, Steele, G, Swordy, SP, Valcarcel, L, Vassilev, VV, Wakely, SP, Weekes, TC, Zweerink, J, Aller, M, Aller, H, Boltwood, P, Jung, I, Kranich, D, Nilsson, K, Pasanen, M, Sadun, A & Sillanpaa, A 2006, 'Multiwavelength observations of the blazar markarian 421 in 2002 December and 2003 January', Astrophysical Journal, vol. 641, no. 2 I, pp. 740-751. https://doi.org/10.1086/500653

Multiwavelength observations of the blazar markarian 421 in 2002 December and 2003 January. / Rebillot, P. F.; Badran, H. M.; Blaylock, G.; Bradbury, S. M.; Buckley, J. H.; Carter-Lewis, D. A.; Celik, O.; Chow, Y. C.; Cogan, P.; Cui, W.; Daniel, M.; Duke, C.; Falcone, A.; Fegan, S. J.; Finley, J. P.; Fortson, L. F.; Gillanders, G. H.; Grube, J.; Gutierrez, K.; Gyuk, G.; Hanna, D.; Holder, J.; Horan, D.; Hughes, S. B.; Kenny, G. E.; Kertzman, M.; Kieda, D.; Kildea, J.; Kosack, K.; Krawczynski, H.; Krennrich, F.; Lang, M. J.; Le Bohec, S.; Linton, E.; Maier, G.; Moriarty, P.; Perkins, J.; Pohl, M.; Quinn, J.; Ragan, K.; Reynolds, P. T.; Rose, H. J.; Schroedter, M.; Sembroski, G. H.; Steele, G.; Swordy, S. P.; Valcarcel, L.; Vassilev, V. V.; Wakely, S. P.; Weekes, T. C.; Zweerink, J.; Aller, M.; Aller, H.; Boltwood, P.; Jung, I.; Kranich, D.; Nilsson, K.; Pasanen, M.; Sadun, A.; Sillanpaa, A.

In: Astrophysical Journal, Vol. 641, No. 2 I, 20.04.2006, p. 740-751.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Multiwavelength observations of the blazar markarian 421 in 2002 December and 2003 January

AU - Rebillot, P. F.

AU - Badran, H. M.

AU - Blaylock, G.

AU - Bradbury, S. M.

AU - Buckley, J. H.

AU - Carter-Lewis, D. A.

AU - Celik, O.

AU - Chow, Y. C.

AU - Cogan, P.

AU - Cui, W.

AU - Daniel, M.

AU - Duke, C.

AU - Falcone, A.

AU - Fegan, S. J.

AU - Finley, J. P.

AU - Fortson, L. F.

AU - Gillanders, G. H.

AU - Grube, J.

AU - Gutierrez, K.

AU - Gyuk, G.

AU - Hanna, D.

AU - Holder, J.

AU - Horan, D.

AU - Hughes, S. B.

AU - Kenny, G. E.

AU - Kertzman, M.

AU - Kieda, D.

AU - Kildea, J.

AU - Kosack, K.

AU - Krawczynski, H.

AU - Krennrich, F.

AU - Lang, M. J.

AU - Le Bohec, S.

AU - Linton, E.

AU - Maier, G.

AU - Moriarty, P.

AU - Perkins, J.

AU - Pohl, M.

AU - Quinn, J.

AU - Ragan, K.

AU - Reynolds, P. T.

AU - Rose, H. J.

AU - Schroedter, M.

AU - Sembroski, G. H.

AU - Steele, G.

AU - Swordy, S. P.

AU - Valcarcel, L.

AU - Vassilev, V. V.

AU - Wakely, S. P.

AU - Weekes, T. C.

AU - Zweerink, J.

AU - Aller, M.

AU - Aller, H.

AU - Boltwood, P.

AU - Jung, I.

AU - Kranich, D.

AU - Nilsson, K.

AU - Pasanen, M.

AU - Sadun, A.

AU - Sillanpaa, A.

PY - 2006/4/20

Y1 - 2006/4/20

N2 - We report on a multiwavelength campaign on the TeV γ-ray blazar Mrk 421 performed during 2002 December and 2003 January. These target of opportunity observations were initiated by the detection of X-ray and TeV γ-ray flares with the All Sky Monitor (ASM) on board the RossiX-Ray Timing Explorer (RXTE) and the 10 m Whipple γ-ray telescope. The campaign included observational coverage in the radio (University of Michigan Radio Astronomy Observatory), optical (Boltwood, La Palma KVA 0.6 m; WIYN 0.9 m), X-ray (RXTE pointed telescopes), and TeV γ-ray (Whipple and HEGRA) bands. At TeV energies, the observations revealed several flares at intermediate flux levels, peaking between 1 and 1.5 times the flux from the Crab Nebula. While the time-averaged spectrum can be fitted with a single power law of photon index Γ = 2.8 from dNγ/dE ∝ E-Γ, we find some evidence for spectral variability. Confirming earlier results, the campaign reveals a rather loose correlation between the X-ray and TeV γ-ray fluxes. In one case, a very strong X-ray flare is not accompanied by a comparable TeV γ-ray flare. Although the source flux was variable in the optical and radio bands, the sparse sampling of the optical and radio light curves does not allow us to study the correlation properties in detail. We present a simple analysis of the data with a synchrotron self-Compton model, emphasizing that models with very high Doppler factors and low magnetic fields can describe the data.

AB - We report on a multiwavelength campaign on the TeV γ-ray blazar Mrk 421 performed during 2002 December and 2003 January. These target of opportunity observations were initiated by the detection of X-ray and TeV γ-ray flares with the All Sky Monitor (ASM) on board the RossiX-Ray Timing Explorer (RXTE) and the 10 m Whipple γ-ray telescope. The campaign included observational coverage in the radio (University of Michigan Radio Astronomy Observatory), optical (Boltwood, La Palma KVA 0.6 m; WIYN 0.9 m), X-ray (RXTE pointed telescopes), and TeV γ-ray (Whipple and HEGRA) bands. At TeV energies, the observations revealed several flares at intermediate flux levels, peaking between 1 and 1.5 times the flux from the Crab Nebula. While the time-averaged spectrum can be fitted with a single power law of photon index Γ = 2.8 from dNγ/dE ∝ E-Γ, we find some evidence for spectral variability. Confirming earlier results, the campaign reveals a rather loose correlation between the X-ray and TeV γ-ray fluxes. In one case, a very strong X-ray flare is not accompanied by a comparable TeV γ-ray flare. Although the source flux was variable in the optical and radio bands, the sparse sampling of the optical and radio light curves does not allow us to study the correlation properties in detail. We present a simple analysis of the data with a synchrotron self-Compton model, emphasizing that models with very high Doppler factors and low magnetic fields can describe the data.

UR - http://www.scopus.com/inward/record.url?scp=33745305002&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33745305002&partnerID=8YFLogxK

U2 - 10.1086/500653

DO - 10.1086/500653

M3 - Article

AN - SCOPUS:33745305002

VL - 641

SP - 740

EP - 751

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 2 I

ER -

Rebillot PF, Badran HM, Blaylock G, Bradbury SM, Buckley JH, Carter-Lewis DA et al. Multiwavelength observations of the blazar markarian 421 in 2002 December and 2003 January. Astrophysical Journal. 2006 Apr 20;641(2 I):740-751. https://doi.org/10.1086/500653