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JVN observations of (NLS1s and) BAL quasars 200 9Mar18-20 EAVN-WS 2009 @ Seoul. Akihiro Doi ( 土居 明広 ) (ASTRO-G/JAXA ) Keiichi Asada, Kenta Fujisawa, Noriyuki Kawaguchi, Hiroshi Nagai, and JVN/OCTAVE collaborators. Coevolution of SMBH & Galaxy?.
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JVN observations of (NLS1s and) BAL quasars2009Mar18-20 EAVN-WS 2009 @ Seoul Akihiro Doi (土居 明広) (ASTRO-G/JAXA) Keiichi Asada, Kenta Fujisawa, Noriyuki Kawaguchi, Hiroshi Nagai, and JVN/OCTAVE collaborators.
Coevolution of SMBH & Galaxy? Kormendy+2000, Credit: K. Cordes & S. Brown (STScI)
Coevolution of SMBH & Galaxy? ← Simulation - Color: temperature - Brightness: gas density When the galaxies and theirblack holes collide a quasar is ignited which expels most of the gas in a strong wind. Remaining galaxy with very little gas but a large SMBH. Di Matteo+(2005) Nature
Rapidly growing Black Holes ■ Narrow-Line Seyfert 1 Galaxy (NLS1) ■ Broad Absorption Line Quasar (BALQSO) BALQSO NLS1 0 -1 -2 -3 -4 -5-6 Quasar Log (L/LEdd ) (Seyfert) Low-luminosity AGN 5 6 7 8 9 10 Log (MBH/ M◎ )
Broad Absorption Line (BAL) quasars CIV 2,000km/s – 0.3c blue-shifted absorption line -> high-velocity outflow
Why BAL in ~30% of QSO? Orientation scenario Every quasar has BAL outflowing toward nearly edge-on directions. e.g, Elvis 2000; Murray et al., 1995 = depending on viewing angle Evolutionary scenario Some quasars in an episodic or young phase have BAL outflows. e.g, Becker et al., 2000; Gregg et al., 2000 = depending on the duration of the phase KEY measurement: ORIENTATION / AGE
Photon-pressure-driven outflow Simulation: Proga, Stone, and Kallman (2000) density velocity ~ 0.1 pc BH disk BAL could be found, when observed from edge-on ?
Orientation Measurement by VLBI imaging ■ Apparent asymmetry :δ, βapp Receding jets 1. deboosted, 2. slower Approaching jets 1. boosted, 2. faster Ex., NGC 4261 (Piner et al. 2001) 1.Doppler Boosting 2.Super-Luminal motion (φ, β)
Size (Age) Measurement by VLBI imaging > 100kpc < 1 kpc ~1-10kpc Kameno 2000 GPS CSS Radio Galaxy RG Size (Age) RG CSS CSS Flux density GPS GPS Spectral Peak Frequency Frequency [GHz]
Only 4 VLBI images for BALQSO (2006) Kunert- Bajraszewska 2006 1045+352 J1556+3517 EVN 1.6 GHz VLBA5 GHz J1312+2319 J0957+2356 EVN 1.6 GHz EVN 1.6 GHz Jiang & Wang 2003
Sample Selection SDSS Parent sample (optical) ・ SDSS 3DR ・ ⇒ Quasars: 46,420 ・ ⇒ BAL quasars: 4,784(Trump et al. 2006) VLA Radio Identification ・ VLAFIRST 1.4 GHz ・ <10”, >1 mJy
Sample Selection: Result ■VLA covered the area for 4374/4784 objects (91.4%) ■ 492 objects found (FIRST BAL = 11.2% SDSS BAL) Histogram of radio-detected BAL quasars N 1st priority: 23object (>100 mJy)
OCTAVE, broad-band subarray in JVN Optically ConnecTed Array forVLBI Exploration Usuda 64m Tomakomai 11m Nobeyama 45m Tsukuba32m Yamaguchi32m 岐阜11m Correlator (NAOJ) Kashima 34m 7 σBaseline Sensitivity~3 mJy ( X-band, 9 min integ. ) 2.4 Gbps
Result: Baseline-detection snapshots Doi & Asada et al. submitted to PASJ ■ 21/23 detected → TB>10^6 K ■ 4/21 showinginverted spectra ( S vs. S ) ⇒ core dominated ⇒ beaming? (νobs= δrestν ) Coexistence: nonthermal jet & thermal outflow (magnetic-pressure-driven & radiative-pressure-driven) VLBI 8GHz VLA 1.4GHz Some BAL quasars have pole-on viewed relativistic jets?
Multi-Freq. VLBI imaging ■ Sample 2 BAL quasars (inverted spectrum) ■ Observations - 1.7 GHz EVN+MERLIN 2008 Mar - 2.3 & 8.4 GHz JVN 2008 Aug - 6.4 GHz JVN 2008 May
Japanese VLBI Network (JVN) ■ Bands (Nant) ・ 6.7 GHz (6) ・ 8.4 GHz (9) ・ 22GHz (9) + 2.3 GHz ? (8) + 43 GHz ? (5) ~3 mas (8.4 GHz)
Results: Multi-Freq. JVN imaging Doi & Asada in prep. unresolved unresolved Giga-hertz Peaked Spectrum (GPS) sources ?( Young Radio Sources?)
Summary ■ VLBI contributions to studies of BALQSOs - Jet Asymmetry -> ORIENTATION - Size -> AGE ■ our JVN/OCTAVE observations - 21/23 detections - coexistence of nonthermal/thermal outflows - 2/4 inverted spectra - unresolved - pole-on viewed? / young? ■ A VLBA proposal accepted !! (L/C/X-bands) for 6 BALQSOs
(Doi et al. submitted) radio-quiet NLS1s radio-loud NLS1s (Doi et al. 2006 PASJ, Doi et al. to be submitted.) NLS1s can generate nonthermal jets; highly relativistic (Dopper-beamed) in some sources DESPITE OF SMALL BHs !!