Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-13T10:01:50.628Z Has data issue: false hasContentIssue false
  • English
  • Français

Multifrequency Polarization Variations in 0917+624

Published online by Cambridge University Press:  12 April 2016

S.J. Qian ,
A. Kraus ,
T.P. Krichbaum ,
A. Witzel  and
J.A. Zensus
S.J. Qian
Affiliation:
Max-Planck-Institut für Radioastronomie, Bonn, Germany
A. Kraus
Affiliation:
Max-Planck-Institut für Radioastronomie, Bonn, Germany
T.P. Krichbaum
Affiliation:
Max-Planck-Institut für Radioastronomie, Bonn, Germany
A. Witzel
Affiliation:
Max-Planck-Institut für Radioastronomie, Bonn, Germany
J.A. Zensus
Affiliation:
Max-Planck-Institut für Radioastronomie, Bonn, Germany

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Intraday variability in compact flat-spectrum radio sources has been intensively studied in recent years. For most IDV events the apparent brightness temperatures derived from the observed timescales are in the range of Tb,app ~ 1016−18 K. For extremely rapid variations, Tb,app can reach up to ~ 1021 K (e.g. Kedziora-Chudczer et al., 1997). Refractive interstellar scintillation may be the most likely extrinsic mechanism (Rickett et al., 1995; Qian, 1994a; Qian, 1994b). Especially for the case of extreme Tb,app (> 1018 K) RISS may be dominant (Dennet-Thorpe and de Bruyn, 2000). However, some IDV events with Tapp ~ 1017−18 K show evidence for an intrinsic origin e.g. the correlated radio-optical intraday variations observed in the BL Lac object 0716+714 (Wagner and Witzel, 1995, Qian et al, 1996). It seems important to distinguish between IDV which is a phenomenon intrinsic to the compact radio sources and IDV which is primarily due to RISS. Multifrequency polarization and VLB I observations would be most helpful (Gabuzda and Kochanev, 1997).

Type
Chapter Three Intra-Day Variability, Gravitational Lensing and Polarization
Information
International Astronomical Union Colloquium , Volume 182: Sources and Scintillations: Refraction and Scattering in Radio Astronomy , 2001 , pp. 119 - 122
Copyright
Copyright © Kluwer 2001

References

Dennett-Thorpe, J. and de Bruyn, A.G.: 2000, ApJ 529, L65.Google Scholar
Gabuzda, D.C. and Kochanev, P.Yu.: 1997, Vistas of Astronomy 41, 219.CrossRefGoogle Scholar
Kedziora-Chudczer, L., Jauncey, D.L., Wieringa, M.H., et al: 1997, ApJ 490, L9.Google Scholar
Qian, S.J.: 1994a, AApS 14, 333 (Transl.: Chin. Astrora. 1995, 19, 69.)Google Scholar
Qian, S.J.: 1994b, AAnS 35, 362 (Transl.: Chin. Astrora. 1995, 19, 267.Google Scholar
Qian, S.J., Li, X.C., Wegner, R., et al.: 1996, Chin. Astrora. 20, 15.Google Scholar
Quirrenbach, A., Kraus, A., Witzel, A., et al.: 2000, A&AS 141, 221.Google Scholar
Rickett, B.J., Quirrenbach, A., Wegner, R., et al.: 1995, A&A 293, 479.Google Scholar
Wagner, S.J. and Witzel, A.: 1995, ARA&A 33, 163.Google Scholar