X-ray Jets with AXIS

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1 X-ray Jets with AXIS

2 AGN jets may contribute to feedback in massive systems from z>6 to z=0, but we do not know How jets are formed What jets are made of Where jets deposit their energy When jets are active Why jets occur Detecting jets and resolving knots requires high spatial resolution. With ~10x Chandra A eff, AXIS will Find many new X-ray jets with less selection bias Find many X-ray AGNs without jets Better characterize known jets High-resolution X-ray imaging is an important counterpart to next-generation radio surveys Jets are charismatic: relativistic, hyper-luminous beams of energy from a giant black hole that can disrupt a galaxy.

3 Origin and Life Cycle What is the launching mechanism? How fast are jets? Is there a fast spine, and slow sheath? Why do only some AGNs have jets? How long do jets live, and where do they decelerate? Where are particles accelerated? VLBI for nearby AGN, X-ray timing, models Measure profiles across a resolved jet; examine diffuse emission outside core Population studies for known jets, AGN X-ray vs. radio morphology, measuring δ from pc-scales to the termination shock Spectra, low-e cutoff in knots, monitoring Composition Why are there FR I, FR II jets? Are jets hadronic or leptonic? Population studies, VLBI, N H from X-rays Radio lobe properties, jet speed Impact Do jets have a single electron population? How and where do jets impact the ISM/ICM? What is the radiative luminosity? Do high-z jets heat the IGM? Do jets misaligned with the ISM trace galaxy/bh mergers? Test IC/CMB at intermediate z (X-ray lobes); γ-ray monitoring Resolve jet-ism interaction sites, jet bending sites; spectra ahead of hot spots Jet speed, composition from above Jet speed, composition, +size/frequency Compare restarted jets, models for X-, Z- shaped radio galaxies

4 Origin and Life Cycle What is the launching mechanism? How fast are jets? Is there a fast spine, and slow sheath? Why do only some AGNs have jets? How long do jets live, and where do they decelerate? Where are particles accelerated? Radio (VLBI), X-ray Radio, IR, optical, X-ray, γ-ray Nearby jets only Radio, X-ray (AXIS focuses on high-z) Radio Radio, X-ray (nearby jets only) Composition Why are there FR I, FR II jets? Are jets hadronic or leptonic? Radio, IR, optical, X-ray Radio lobe properties, jet speed Impact Do jets have a single electron population? How and where do jets impact the ISM/ICM? What is the radiative luminosity? Do high-z jets heat the IGM? Do jets misaligned with the ISM trace galaxy/bh mergers? Radio, optical, X-ray, γ-ray Radio, X-ray, γ-ray (mostly nearby, but some at z>1) Radio, X-ray Radio, X-ray, γ-ray (based on nearby jets) (Radio), X-ray

5 Do jets have a single electron population? How and where do jets impact the ISM/ICM? Do high-z jets heat the IGM? Why do only some AGNs have jets? How fast are jets? Where are particles accelerated? IC/CMB models predict X-ray jet enhancement at z>1, so search for them. Detect compact kpc-scale jets at high-z, measure (1+z) 4 effect Map jet-ism interaction zones at z 1, resolve jets in the epoch when clusters form and isolate jets from ICM (Chandra ok locally) If IC/CMB model is wrong (2 nd synchrotron pop. makes X-rays), then frequency, power yields radiative luminosity in each Δz Deep surveys needed to answer why there is a deficit of high-z radio galaxies, determine ratio of FR I/II at high-z, as a function of environment. Highresolution X-rays complement SKA, etc. Monitor for flares; measure δ from X- rays (assuming IC/CMB or synchrotron); Resolve nearby, well known jets and separate spatially+spectroscopically Monitor nearby quasar jets, blazars; obtain high S/N spectra from jet knots in FR I and II jets. θ<1, A 1 kev > 5000 cm 2, FOV>15 (30 is better for a blind search). θ<0.3 to identify jets near quasars w/ contrast of 1-10% (cores may be important for FSRQs) θ<0.5, A 2 kev > 3000 cm 2, FOV=N/A θ<1 across FOV, A 2 kev = cm 2, FOV~30 to catch jets in deep fields (for compact jets near bright core, θ<0.5 is better) θ<1 across FOV, A 1 kev > 5000 cm 2, FOV~30 (for deep fields) θ<0.5 (0.1 better), A 2 kev > 3000 cm 2, FOV=N/A θ<0.3, A 1 kev > 3000 cm 2, FOV>15

6 Do jets have a single electron population? How and where do jets impact the ISM/ICM? Do high-z jets heat the IGM? Why do only some AGNs have jets? How fast are jets? Where are particles accelerated? IC/CMB models predict X-ray jet enhancement at z>1, so search for them. Detect compact kpc-scale jets at high-z, measure (1+z) 4 effect Map jet-ism interaction zones at z 1, resolve jets in the epoch when clusters form and isolate jets from ICM (Chandra ok locally) If IC/CMB model is wrong (2 nd synchrotron pop. makes X-rays), then frequency, power yields radiative luminosity in each Δz Deep surveys needed to answer why there is a deficit of high-z radio galaxies, determine ratio of FR I/II at high-z, as a function of environment. Highresolution X-rays complement SKA, etc. Monitor for flares; measure δ from X- rays (assuming IC/CMB or synchrotron); Resolve nearby, well known jets and separate spatially+spectroscopically Monitor nearby quasar jets, blazars; obtain high S/N spectra from jet knots in FR I and II jets. θ<1, A 1 kev > 5000 cm 2, FOV>15 (30 is better AXIS for a blind search). Survey θ<0.3 to identify jets near quasars w/ contrast of 1-10% (cores may be important for FSRQs) θ<0.5, A 2 kev > 3000 cm 2, FOV=N/A AXIS Targeted θ<1 across FOV, A 2 kev = cmaxis 2, FOV~30 to Deep catch jets in Fields deep fields (for compact jets near bright core, θ<0.5 is better) θ<1 across FOV, A 1 kev > 5000 cm 2, FOV~30 (for deep fields) AXIS Deep Fields θ<0.5 (0.1 better), A 2 kev > 3000 cm 2, FOV=N/A Chandra ok θ<0.3, A 1 kev > 3000 cm 2, FOV>15 Chandra ok

7 IC/CMB vs. Synchrotron in X-ray Jets X-ray jets are often too bright to be synchrotron from the same population that emits in radio. Inverse Compton scattering of the CMB was proposed, but it predicts stronger GeV flux than is seen (also, X-ray counter-jets are seen in some sources, and X-ray/radio offsets in jet knots). An alternative hypothesis is that X-rays are synchrotron from a second, more energetic population. A better accounting for cooling processes may solve the problem; a prediction is that there should be a z>2 population of X-ray jets with no radio counterpart (due to (1+z) 4 increase in CMB energy density, see Andy Fabian s presentation). AXIS will find these jets, or not, and also test the expected (1+z) 4 brightening to determine whether quenched radio jets explain the ratio of blazars/radio galaxies at z>2 (Volonteri+2011, Ghisellini+2015) References M. Lucchini et al. 2017MNRAS L H. Gaur et al. 2017arXiv G E. Meyer et al. 2017ApJ...835L..35M A. Simionescu et al. 2016ApJ...816L..15S M. Georganopoulus et al. 2016Galax G E. Meyer et al. 2015arXiv M G. Ghisellini et al. 2015MNRAS G M. Volonteri et al. 2011MNRAS V

8 PKS Georganopoulos+2017

9 PKS From variable component (core, not extended jet) Upper limits to extended jet Lucchini+2017 Revised model with radiative and adiabatic cooling

10 B (Radio on Smoothed X-rays) -- Simionescu+2016 ATHENA WFI HEW

z=2.5, CXO 20 ks Quasar L X =2x10 45 erg/s Jet L X =

= 1x10 42 erg/s Quasar L X =2x10 42 erg/s Jet L X =

11 z=2.5, CXO 20 ks Quasar L X =2x10 45 erg/s Jet L X = 1x10 44 erg/s z=2.5, AXIS 10 ks (simx) Quasar L X =2x10 44 erg/s Jet L X = 1x10 43 erg/s Quasar L X =2x10 43 erg/s Jet L X = 1x10 42 erg/s Quasar L X =2x10 42 erg/s Jet L X = 1x10 41 erg/s This is comparable to luminosities in local jets, so lower selection bias

12 Where do jets deposit energy? Jet-driven molecular outflows indicate that jets directly deplete gas Jet-ISM interaction can be seen in radio+optical/ir or radio+x-rays (synchrotron+thermal emission from shocked gas). X-rays are sometimes ahead of termination shocks, and are ~calorimeters for heating. At 0.3 resolution, for S/N=5, can centroid to <1 kpc for z 1 distinguish jet-ism interaction zones from hot spots. Long exposures could still be needed: At z=1, for 5000 cm 2 at 1 kev for AXIS, relative to Chandra at 100 Mpc the observing time is ~360x higher (at z=0.25 and 0.5, it is 13x and 66x higher). z=0.25 is still a factor of 2000 more search volume, but only up to 3 Gyr ago. Caveat: some distant jets are pretty bright ( Positive feedback from ISM compression: more effective at z=2-3? (Gaibler 2014). AXIS can resolve jets from cores and hot gas. References Worrall et al. 2016MNRAS W, 2012MNRAS W Lanz et al. 2015ApJ L V. Gaibler 2014AN G Erlund et al. 2010MNRAS E Ly et al. 2005ApJ L

13 CXO HST X-ray and optical offset from radio Worrall+2016

14 1.4 GHz on X-ray Gemini image Chandra contours (off-axis point source) True hot spot MERLIN radio Erlund, Fabian+2010

15 Lanz+2015 X-rays offset from radio hotspot

16 How fast are jets? Doppler factor δ=3-20 inferred from blazars with IC/CMB model populations, superluminal motion. But, they could be slower if the X-ray is synchrotron (Georganopoulus+2016). Speed matters for: Reach of feedback Particle acceleration Radiative jet luminosity (Georganopoulos+2016) Spine/sheath models predict faster, highly magnetized spine (Mizuno+2007); jet structure can be probed through polarization, shocks in blazars, and flares, but AXIS can resolve knots. This is independent of the IC/CMB vs. synchrotron issue. Need to sample PSF well enough for a good model. FR II/FSRQ jets seem to remain relativistic longer than FR I/blazar jets. Is this a function of environment, jet launching mechanism, composition, etc.? AXIS can measure the relative frequency at higher redshift as part of a search for the missing radio galaxies (Volonteri+2011). References: B. Hogan et al. 2011ApJ H V. Marchenko et al. 2017ApJ M Y. Mizuno et al. 2007ApJ M

17 Radio + contours Deconvolved X-ray After deconvolving with a model of the Chandra psf, the X-ray jet is resolved in the transverse direction with a width of ~500 pc Spine-sheath? X-ray Marchenko+2017

18 z=0.3, L jet =10 41 erg/s 75 ks simx Spine/sheath (0.5 kpc wide) Spine only (unresolved) Transverse width is tightly measured Since there are multiple bright X-ray jets, AXIS is better than Chandra but not 10x better.

19 Where do jets accelerate particles? Variability probes size of emission region. X-rays in core (disk/corona) are counterparts to radio, γ-ray variability but A eff is more important than resolution (blazar region may be sub-pc) High-resolution X-rays instead probe knots/hotspots (could be more energetic than TeV blazars; Kataoka+2008); i.e., diffusive shock acceleration. Radio vs. X-ray dominance may indicate different B-field (Hardcastle+2004). See prior slides for in situ acceleration constraints for offset X-ray, radio Spectral evolution on <1d from kev constrains minimum Lorentz factor, size of shock region, participating particles (e.g., Kataoka+2007); at 2<z<4 AXIS may be able to get soft and hard band simultaneously (but Athena works, too). Multi-wavelength (radio/ir/optical/x-ray) data needed to strongly constrain models. References E. Meyer et al. 2015Natur M J. Kataoka et al. 2008ApJ K M. Hardcastle 2004ApJ H

20 Why do only some AGNs have jets? Major, multi-threaded topic Spin? Eddington ratio? Environment? Age? No explanation seems fully to work X-rays: monitoring (nearby), samples (X-ray selected, going further down luminosity function and to higher z, follow-up to FIRST and next-generation radio surveys, etc.) With sufficient FOV, AXIS can expand the sample of both X- ray selected AGN and radio-selected AGN at high redshift. Chandra provides a lot of data; FR I/II divide is characterized observationally, and sensitive, milliarcsec radio observations (SKA, ngvla) may be more important.

21 Non-AGN X-ray Jets ULX jets (Urquhart+2017, in prep; 2017HEAD U; Cseh MNRAS.439L...1C) Microquasars (Romero SSRv R)

22 H X-ray ejecta discovered in a microquasar evolved over a month. AXIS resolution + effective area lead to centroiding for similar brightness, exposure time as CXO observations (cf. JVLA). Monitoring these systems for state transition (through standing ToO) probes jet formation, ISM interaction. Corbel+2005

23 X-ray jet gallery: Various (observed) jet experts (who published new results since 2014) L. Saripalli D. Lal D. Worrall/M. Birkinshaw P. Kharb C. Cheung [mostly novae now] E. Meyer A. Siemiginowska M. Georganopoulos F. Massaro H. Krawczynski [mostly polarization, accretion now]

The Case of the 300 kpc Long X-ray Jet in PKS at z=1.18

The Case of the 300 kpc Long X-ray Jet in PKS at z=1.18 SLAC-PUB-12762 astro-ph/78.1312 Extragalactic Jets: Theory and Observation from Radio to Gamma Ray ASP Conference Series, Vol. **VOLUME**, **YEAR OF PUBLICATION** T. A. Rector and D. S. De Young (eds.)