Radio-loud Narrow-line Seyfert 1 galaxies introduction & motivation: - radio-loud radio-quiet bimodality - NLS1 galaxies GAVOGAVO search for radio-NLS1s multi- properties of radio-loud NLS1s models future follow-ups Stefanie Komossa, MPE Garching in collab. with, W. Voges, S. Mathur, D. Xu, H.-M. Adorf, G. Lemson, S. Anderson,. W. Duschl From Atoms to AGN, Tel Aviv, Feb. 2006
radio-loud NLS1s introduction: RL-RQ bimodality `RL-RQ´ dichotomy: quasars come in two flavors, radio-quiets and radio-louds with deficiency of sources at intermediate radio powers/indices [e.g., Kellermann et al. 89, Visnovsky et al. 92, Hooper et al. 95] recently debated: some samples don‘t [e.g., Cirasuolo & 03, White & 00], others do show the bimodality [e.g., Ivezic & 02, Sulentic & 03] what makes an object radio loud ? [e.g., Blandford 00, Wilson & Colbert 95, Laor 00, Ye & Wang 05, Best & 05, Metcalf & Magliochetti 05]
radio-loud NLS1s introduction: RL-RQ bimodality RL-RQ dichotomy in radio index (R) histogram R = f 5GHz / f 4400A R 5 > 10 (R 1.4 > 19) : RL [Kellermann et al. 89] RL-RQ distinction in `emission-line diagram´: [Sulentic et al. 03] 0 1 2 3
introduction: NLS1 galaxies open questions, addressable with radio studies orientation m BH – plane jet-disk coupling ? indications that Gal. XRBs in soft/hi state and AGN close to L Edd are radio weak.... This is the first systematic study of radio-loud NLS1s and their multi- properties*. Only 3-4 RL NLQSOs known previously: PKS0558-504, [Remillard & 86, Siebert & 99], RXJ0134-4258 [Grupe & 00], SDSS0948+0022 [Zhou & 03], SDSS1722+5654 [Komossa & 06], plus 1-2 cand.; and almost no prev. syst. radio studies of NLS1s [Ulvestad & 95, Moran 00, Greene & 06] * one study in parallel: [Whalen & 06, astro-ph]
GAVO GAVO search for radio-loud NLS1s cross-correlation of the Catalogue of quasars and AGN [Veron-Cetty et al. 2003] with radio and m B cat s using the matcher developed within the German Astrophysical. Virtual Observatory, http://www.g-vo.org, [Adorf et al. 05] catalogues: PKS (4.85 GHz) PMN, 87 GB (2.7 GHz) VQC NVSS, FIRST (1.4 GHz) SUMSS (0.8 GHz) WENSS (0.3 GHz) USNO-A,B SDSS spec. GSC2.2 ROSAT, IRAS radio mBmB [Wright & Otrupcek 90, Griffith & 94, Gregory & Condon 90, Condon & 98, White & 97, Mauch & 03, de Bruyn & 98] [Monet & 03] [York & 00, Voges & 97] opt X, IR RL
search for radio-loud NLS1s: results 128 NLQSOs in VQC 90% within NVSS survey area, among these, 7% are radio-loud only ~2% exceed R=100 (for comp.: ~ 15% radio-louds among quasars) most radio-loud NLQSOs are compact, steep spectrum sources, not variable might be partly, but not fully, due to NLS1 definition as FWHM H < 2000 km/s, indep. of L
radio-loud NLS1s: results FeII-[OIII]-FWHM H correlations: - radio-louds cover whole FeII-[OIII] range of NLS1s, - extend known radio-loud objects to those with small FWHM H [Marziani & 01]
radio-loud NLS1s: results black hole masses*: - unusually low, given the radio-. loudness of the galaxies, but at upper end of NLS1s; - in a prev. rarely populated regime of the `Laor diagram´ * estimated from L (5100A) and FWHM H [Kaspi & 05]
radio-loud NLS1s : models starburst contribution ? - radio powers P are all in RL regime - IRAS – radio corr.: P factor 10- 120 above expected starburst contrib. - ionisation para., SDSS1722+56: log U ~ -2.4 (typ. for Sy) EUV excess: NeIII/NeV is good indicator of continuum shape, once U is known
radio-loud NLS1s: models to explain lower frequency of RLs among NLS1s relativistic beaming ? pole-on view - most are steep spectrum sources, with radio spectral indices r < -0.5; beaming not expected - exceptions: SDSS0948+0022, RXJ16290+4007: r =0.6, 0.4 - SDSS0948+0022 var. in radio, PKS0558 highly var. in X - X-ray spectra of beamed sources typically much flatter : beaming cannot be excluded, but no positive evidence for it, with 2-3 exceptions Why are RL NLAGN more rare than RL BLAGN, and is the mechanism for RLness the same in NLAGN and BLAGN ?
radio-loud NLS1s: models to explain lower frequency of RLs among NLS1s accretion mode: in Gal. X-binaries in soft/high-state (&AGN), radio emi. quenched for high acc. rates [e.g., Maccarone &03, Greene & 06]. mechanism which suppresses radio- emi for high L/L Edd also responsible for low RL-fraction in NLS1s ? RL NLS1s: Eddington ratios: 10 L x /L Edd = 0.2-6 -- more theoret. studies needed -- spin: spin-jet coupling e.g. via Blandford-Znajek or Blandford- Payne mechanism. Why, NLS1s on ave. less rapidly spinning BHs ? BHs still growing ?? Then, few RL ones should be more evolved. Indeed, they are closer to M BH – relation of AGN than other NLS1s [Mathur & Grupe 05]
radio-loud NLS1s: follow-up studies larger samples, based on SDSS: low-L NLS1s; radio-loudness etc. in dependence of FWHM; interesting individual objects (jet sources ?) optical spectroscopy: line-profiles, exti, R, M BH make use of line ratios wih diagn. power radio imaging: how compact are the sources ? at diff. : spectral indices, steepness monitoring: variability, beaming ? X-rays: spectra, absorption, variability theory: jet-disk models, dep. on acc. rate
Summary identification of RL NLS1s radio: most sources are compact, of steep spectrum, and not variable; R of all det. sources covers > 4 orders of mag. BH masses in prev. rarely populated regime of Laor diagr. opt-X prop. similar to RQ NLS1, radio properties extend the range of RLness to small FWHM H fraction of RL NLS1s (7%) < RL BLQSO mech.: no SBs, no positive evidence for beaming in most sources, so far. Accretion mode & spin ? future: larger samples; radio-obs: compactness of sources, spectral indices, variability; + multi- [Komossa et al. 06a, ApJ 639, in press; 06b, AJ, subm.]
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