Jets and accretion in ɣ -ray emitting Narrow Line Seyfert 1s J OSEFIN L ARSSON KTH & Oskar Klein Centre, Stockholm 1
Supermassive black holes and jets Blazar Central supermassive black hole with Type 1 mass ~ 10 6 - 10 10 M ⦿ Type 2 ~ 15% of AGN have large-scale relativistic jets Jet formation is poorly understood Jets are almost exclusively found in large elliptical galaxies with massive black holes (M > 10 8 M ⦿ , e.g, Sikora+2007 , Chiaberge+2011 ) 2
What is a NLSy1? Defined from optical spectra: It’s a Seyfert 1 where the • FWHM (H β ) < 2000 km s -1 broad lines are kind of narrow. • [O III]/H β < 3 • Strong Fe II bump Other properties 3 soft excess • Spiral host galaxies Data/Model ratio 2.5 • Lower fraction of radio loud objects (~ 7%, Komossa+2006 ) ratio 2 • X-rays: rapid large-amplitude variability, 1.5 steep spectra, strong soft excess. ( Boller+1996, Gliozzi+2020 ) 1 0.5 1 2 5 10 Energy (keV) Energy (keV) 3
What is a NLSy1? Usually interpreted as “low-mass” black holes (~ 10 6 - 10 7 M ⦿ ) with high accretion rates. No fundamental difference compared to regular Seyfert 1s, but interesting as they occupy an extreme end of AGN parameter space 4
Detection of ɣ -ray emission from NLSy1s In 2009, the Fermi gamma-ray space telescope detected gamma-ray emission from a NLSy1 for the first time, revealing blazar-like properties ( Abdo+09 ). 9 ɣ -ray NLSy1s (z ~ 0.06-0.8) in the 4th Fermi LAT source catalogue • (compared to ~2000 blazars, Abdollahi+2019 ) ~20 “candidate” ɣ -ray NLSy1s (e.g. Paliya+2018 ) • Are we really seeing powerful jets from low-mass black holes hosted by spiral galaxies? 5
Evidence for relativistic jets SEDs similar to Flat Spectrum Radio Quasars (FSRQs), including ɣ luminosities ~ 10 44 -10 48 erg s -1 and steep ɣ -ray spectra (photon indices ~2.5). (Abdo +09 ) 6
Evidence for relativistic jets Rapid multiwavelength variability. High and variable polarisation. MJD=56281 MJD=56283 6.0 [10 -12 erg/cm 2 /s] Total Flux (R C ) Tot. Flux 4.0 2.0 40 P.D. 30 P. D. [%] 20 10 0 -90 90 17 18 19 20 21 17 UT [hour] Optical observations of Gamma-ray flares in SBS 0846+513 PMN J0948+0022 (Itoh +13 ) (D’Ammando+13) 7
Evidence for relativistic jets Radio properties: flat or inverted spectra, strong variability, pc-scale core- jet structures and superluminal motion. MOJAVE observations of the radio jet in 1H0323+342. quasi-stationary point at 7 mas (~100 pc). Recollimation shock - possible site of ɣ -ray emission. (Doi+18) 8
Black hole masses Viral mass estimates give 10 6 - 10 7 M ⦿ , but may be underestimated due to effects of radiation pressure and/or a flattened BLR. Other methods, such as accretion disc fitting give higher masses ( e.g. Calderone+2013 ) Summary of results for the ɣ -ray NLSy1s 1H0323+342 [M � ] 10 7 single-epoch H β 1H0323+342 [156] 2 10 7 P α [89] 6 10 6 [139], f BLR = 1 reverberation mapping 3 10 7 [139], f BLR = 6 10 7 (opt–UV) SED modelling [2] 2–4 10 8 host galaxy [93] 10 7 X-ray excess variance [147] 3–8 10 6 PSD break frequency [117] 4–6 10 6 single-epoch H β PKS 1502+036 [150] (Komossa+18) 9
Host galaxies Limited information due to relatively high redshifts for many ɣ -ray NLSy1s. Some interesting examples: NOT (R band) SDSS (r band) 1H0323+342 (z=0.063) SDSS J2118-0732 (z=0.26) Recent merger or one-armed Disturbed morphology, possible spiral? (Leon merger (Yang+18) . Tavares+14) 10
VLT/ISAAC (J band) VLT/ISAAC (J band) PKS 1502+036 (z=0.41) PKS 2004-447 (z=0.24) Elliptical with some circumnuclear pseudobuldge+disc+bar (no structure (D’Ammando+18) . evidence of merger) (Kotilainen+16) . GTC/CIRCE (J band) FBQS J1644+2619 (z=0.15) Barred lenticular (Olguin-Iglesias+17) or elliptical (D’Ammando+17) . 11
X-ray emission from non-jetted AGN 10 4 Compton hump 5000 10 4 Fe line E F E E F E E F E E F E 2000 1000 Reflection spectrum Reflection spectrum Power-law from corona 1000 0.1 1 10 100 0.1 1 10 100 Energy (keV) Energy (keV) Energy (keV) Energy (keV) + reflection from distant material - absorption + soft excess (?) (from Athena White paper) 12
Models for the soft excess 1. It is simply part of the reflection spectrum. Compton hump Soft excess seems too strong for 10 4 this explanation in many cases. Fe line E F E Soft E F E Solved with higher density disk excess ( Jiang+19)? 1000 Reflection spectrum Reflection spectrum 0.1 1 10 100 Energy (keV) Energy (keV) 2. It is due to Comptonisation in an topically thick ( 𝝊 ~10-20) warm (kT~0.5 keV) corona How is this produced? Would it be stable? (Petrucci+20) 13
X-ray emission from blazars Relativistically beamed emission from the jet completely dominates the X-ray spectrum. Power-law spectrum. Synchrotron or Inverse Compton depending on the type of blazar. What are the properties of the inner accretion flow and coronae in AGN with jets? 14
X-ray spectra ɣ -ray NLSy1s 2-10 keV spectra well fitted by hard power law ( Γ ~ 1.2-1.8) More similar to FSRQs than RQ NLSy1s! ( Kynoch+18) No broad Fe lines. Narrow Fe lines from distant material in one case (1H0323+342). Energy (keV) Inverse Compton emission from the jet dominate the spectra above 2 keV. 15
Soft X-ray excess 1H0323+342 3 The majority of sources with good- 2.5 quality X-ray spectra show excess Data/Model emission when the hard power law is ratio 2 extrapolated to low energies. This is 1.5 vary rare in blazars. 1 0.5 1 2 5 10 Energy (keV) Energy (keV) PMN J0948+0022 J1222+0413 FBQS J1644+2619 10 0 1orm CtV V −1 NeV −1 1orm CtV V −1 NeV −1 1orm CtV V −1 NeV −1 10 0 10 0 10 −1 10 −1 10 −1 10 −2 10 −2 10 −2 10 −3 10 −3 2.25 2.5 1.4 2.00 DDtD/0odel DDtD/0odel DDtD/0odel 2.0 1.75 1.2 1.50 1.5 1.25 1.0 1.00 1.0 0.75 0.8 0.5 0.50 0.3 1.0 10.0 0.3 1.0 10.0 0.3 1.0 10.0 (nergy (NeV) (nergy (NeV) (nergy (NeV) 16
Soft X-ray excess The full 0.5-10 keV spectrum is usually well described by a broken power law with a break at ~ 2 keV. No evidence for intrinsic absorption. 2.2 2.0 1+ 0323+342 -2118-0732 1.8 Γ 1 1.6 FB46 M1644+2619 3.6 2004-447 301 -0948+0022 1.4 3.6 1502+036 -1222+0413 1.2 1.0 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 Γ 1 Broken power-law fits to the X-ray spectra of ɣ -ray NLSy1s (only highly significant ɣ -ray sources with XMM observations) 17
Physical models for the X-ray emission: FBQS J1644+2619 as an example Highest ɣ -ray flux recorded 1.6 in 2012 ( D’Ammando+15) 1.4 1.2 iste (couttR R − 1 ) 10 -10 1.0 0.8 10 -11 0.6 ν F ν (erg cm − 1 s − 1 ) 10 -12 0.4 XMM EPIC pn light curve 0.2 10 -13 0.0 0 20000 40000 60000 80000 Time (R) 10 -14 Grey intervals affected by high 10 -15 background, excluded from spectral FB46 -1644+2619 this work analysis FB46 -1644+2619 arFhival 10 -16 10 7 10 9 10 11 10 13 10 15 10 17 10 19 10 21 10 23 10 25 10 27 Frequency (Hz) 80 ks XMM-Newton observation in 2017 together with MW campaign (Medicina, REM, Swift , Fermi ). (Larsson+18) 18
Simple models 10 0 Norm Cts s − d keV − d 10 -1 Γ = 1.82 ± 0.01 Power law 10 -2 Χ 2 /d.o.f. = 478/355 10 -3 Γ 1 = 1.90 ± 0.02 1.6 Γ 2 = 1.66 ± 0.03 Broken Dsts / Model 1.4 E break = 1.9 ± 0.3 keV power law 1.2 Χ 2 /d.o.f. = 349/353 1.0 0.8 0.3 1.0 10.0 etergk (keVD The X-ray spectrum is well described by a broken power law The jet dominates the spectrum above the break: The hard photon index is compatible with FSRQs, but much harder than in radio-quiet NLSy1s. No detection of an Fe line at 6.4 keV. No intrinsic absorption. The low-energy part of the spectrum likely has a contribution from the underlying Seyfert emission. 19
I: Jet emission + ‘standard’ corona 4 2 pow 2 0 χ −2 −4 −4 4 relxilllp 0.3 1.0 10.0 Energy (keV) Power law + power law The photon index for the 2nd power law is 2 . 01 + 0 . 14 Γ 1 extremely hard, even for a jet. The � 1 0 ⇥ � 0 . 07 4 4 0 4 10 � 4 1 . 0 + 0 . 3 Norm predicted hard X-ray flux is inconsistent Γ 2 � 4 ⇥ � 0 . 4 with the non-detection by Swift/ BAT. 10 5 χ 2 / d . o . f . 348/353 20
II: Jet emission + warm corona keV 2 (Ph cm − 2 s − 1 keV − 1 ) 10 10 -3 10 10 -4 10 T otal 10 -5 10 PL 10 CompTT 10 -6 0.3 1.0 10.0 10 Energy (keV) pow +comptt 4 2 0 χ −2 Power law + CompTT −4 0.3 1.0 10.0 Energy (keV) 1 . 64 + 0 . 05 Γ − 0 . 05 × − 0 . 08 26 f 4 18 0 03 10 − 4 kT 0 (eV) PL Norm Optical depth and temperature of the 0 . 30 + 0 . 21 kT e (keV) ‘warm’ corona similar to typical parameters − 0 . 11 16 + 11 τ − 0 5 × found for RQ sources. − 4 χ 2 / d . o . f . 1.4 0 . 3 10 − 2 346/352 Norm 21
III: Jet emission + reflection keV 2 (Ph cm − 2 s − 1 keV − 1 ) 10 10 -3 10 10 -4 10 T otal 10 10 -5 PL 10 relxilllp 10 -6 0.3 1.0 10.0 10 Energy (keV) −4 4 relxilllp 2 0 χ −2 Rexilllp −4 −4 0.3 1.0 10.0 ± Energy (keV) log ξ ( 1 . 6 + 0 . 3 h ( r g ) 45 ⇤ � 34 � 0 . 2 0.998 f 1 f a A Fe Large height for the base of the jet. No 5 f incl ( � ) ) R 5 (k 0 0 . 88 ⇤ R � 0 . 15 significant emission from the innermost 1 . 4 + 40 . 8 3 8 R in ( r g ) ⇥ ⇤ � accretion disc. χ 2 / d . o . f . 355/351 1 . 78 ± 0 . 01 Γ 22
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