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Multi-frequency radio observations of BAL quasar 1045+352 Magdalena Kunert-Bajraszewska Toruń Centre for Astronomy, N. Copernicus University.

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Presentation on theme: "Multi-frequency radio observations of BAL quasar 1045+352 Magdalena Kunert-Bajraszewska Toruń Centre for Astronomy, N. Copernicus University."— Presentation transcript:

1 Multi-frequency radio observations of BAL quasar Magdalena Kunert-Bajraszewska Toruń Centre for Astronomy, N. Copernicus University

2 Features of BAL quasars - very broad, blue-shifted absorption lines arising from: - high-ionization transitions e.g. CIV 1549  HiBAL quasars - low-ionization transitions e.g. MgII 2800  LoBAL quasars; -lack of radio emission, only radio-quiet objects; - orientation hypothesis: - all quasars have BAL region - the BAL features are visible along a particular line of sight, e.g. line of sight skimming the edge of the accretion disk or torus (Weymann et al., 1991, Elvis 2000); - the line of sight intersects an outflow or wind from the accretion disk (Murray et al., 1995) (until 1997!)

3 Radio-loud BAL quasars -discoveries of radio-loud BAL quasars: Becker et al., 1997; Becker et al., 2000 Menou et al., 2001; Brotherton et al., 1998 compact objects!wide range of orientation! J FIRST J first known BAL+FRII quasar Gregg et al., 2000, ApJ, 544, 142 VLA 1.4 GHz EVN 1.6 GHz compact BAL quasar Jiang & Wang, 2003, A&A, 397, L13

4 Radio-loud BAL quasars „unification by time” Becker et al., 2000; Gregg et al., BAL quasars as young or recently refuelled quasars; < 10 5 years ! -evolutionary sequence: compact BAL QSO  LoBAL+FRII  HiBAL+FRII

5 BAL quasar It is a HiBAL quasar. Willott et al., 2002, MNRAS, 331, 435

6 BAL quasar VLBA 1.7 GHz MERLIN 5 GHz NE SWSE NW VLBA 5 GHzVLBA 8.4 GHz 2.1 kpc ~10 4 yr

7 BAL quasar one of the most radio-luminous BAL quasars: logL =27.65 W Hz -1 ; log(R * )(total) ~ 5.2 (4.4) log(R * )(core) ~ 4.0 (3.2) 1.4 GHz - radio-loudness parameter (Stocke et al., 1992): definition: log(R * ) > 1  radio-loud object log(R * )=log(f 5GHz ) – log(f 2500Å )

8 Orientation of log(R v )=log(L core ) + 0.4M v – Wills & Brotherton, 1995, ApJ, 448, L81 5 GHz log(R v ) ~ 3.2  ~ 20°

9 Submillimetre emission GHz flux density measured with OCRA-p (Toruń 32-m telescope) S=69 mJy +/- 7 mJy,  = GHz 4.85 GHz log S log v 850  m and 450  m Willott et al., mm Haas et al., 2006 radio emission - hyperluminous infrared quasar (Willott et al., 2002, MNRAS, 331, 435) >40%

10 BAL quasar Summary - it is a compact, young CSS object and it is consistent with the theory of BAL quasar evolution; - its radio emission is boosted; - the angle between the line of sight and the jet axis is very small, ~20°; - the submillimetre flux is dominated by synchrotron emission, the large dust mass does not coexist with BAL phenomenon; - the radio structure can indicates intermittent activity;


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