ulxs and their environments: a meeting...

ULXs and their environments: a meeting summary

Tim RobertsSteal some

nice pictures!

P13

How do you do a summary talk?

o Gradual sense of panic building for last month

o Then it struck me: workshops should be about answering questions

o So I wrote down some key questions:n What are ULXs?n How does super-Eddington accretion work?n What’s the effect of a ULX on its environment?

Thursday 16th June 2016 Tim Roberts - Summary talk 2

Firstly: an apology

o I can’t mention all the talks due to time limitations.

o If I’ve missed yours out it’s no comment on its contents(!), and I apologise profusely. Really. Particularly if your talk is this morning as I’ve (mostly) written this last night.

o Quality of figures may be poor (screen grabs)


Evidence for super-Edd ULXs?o Motch talk – P13o Spectra, light curve

modelling & Roche lobe constraints imply MBH < 15 M¤ & LX > Ledd

o Show ultraluminousspectra when super-Eddingtonn By extension most ULXs!


What are ULXs?

Chandra 2003

XMM 2013

kTin ~ 0.2 keV

kTe ~ 2 keV

diskbb + comptt

Cf. Middleton, Bachetti talks

Other optical mass functions?o Fabrika – spectra of

ULXs very similaro Described by SCAD

models; can’t see secondary star features

o Except for faintest (MV ~ -4) that have F/G-like spectra


NIR mass functionso Lopez/Heida – IR

c’parts less likely to be disc-dominatedn Better for mass fnn Tho’ periods long

o 47 NIR c’partsfound; 23 RSGs

o Initial spectra for 6; 3 RSGs


Can rule out short period, massive BHs from lack of RV change in 1 year for

J0047 in NGC 253 (Heida)

Proportion of ULXs that are IMBHs?o Webb – HLX-1 remains poster child for

IMBHs, but as a class they’re rareo Other candidate IMBHs: M51 X-7, CXO

J1225, NGC 2276 3c…o Zolotukhin – 16/98 new HLX candidates likely

bona fide (but which ones? Why found preferentially in spirals?)

o Wolter – 3 candidates from ring galaxieso Find new IMBHs in TDEs/small galaxy nuclei?


What are ULXs?

Any other underlying populations?o At least one NS

(Bachetti et al. 2004, opposite)

o Pintore talk – can’t exclude simple phenomenological NS models for NGC 1313 X-1

o Wictorowicz – extreme mass transfer rates, even in NS binaries


What are ULXs?

Physics of accretion flow (models)o All supercritical

accretion models converging on same structure

o Ohsuga/Mineshige – funnels, clumpy outflows, Poutflow = Lrad


How does super-Edd accretion work?

Physics of accretion flow (data)

o Middleton: big picture spectral-variability characteristics are consistent with funnel models with clumpy winds


Luangtip et al. (2016)

o Swift spectra for Ho IX X-1 stacked by flux and hardness – evidence for precession


Note precession in SS433

(Fabrika 2004); also highly

likely in P13 (Motch talk),

NGC 1313 X-1 (Middleton

talk), NGC 4395 (Vinokourov et

al. 2016)…

Lsoft goes as mdot; Lhard as mdot2

Disc-like spectra at highest LX

o Seen in Ho IX (Luangtip et al 2016, Walton et al. 2014), NGC 1313 X-2 (Pintore & Zampieri2012), NGC 1313 X-1 (Yoshida talk) – hard component beamed and downscattered in funnel?


From Yoshida

talk

From Sutton et al (2013)

BDHULSULHigh absorption

X-ray – optical properties from SCAD


Vinokourov talk

Note other models for optical emission – Ambrosi talk

Link with sub-Edd BHBs?o Kubota: possible similarities in spectral shape

between VHS and ULXso Shidatsu: GRO J1655 ultrasoft outburst shows

Compton-thick wind (very like ULXs)o Sutton: discs in BHBs at 0.1 Eddington also

appear broad (next slide)n Could mean BD ULXs are MsBHs (40 – 90 M¤) at

0.1-0.3 Eddingtonn Also plausible we don’t understand disc physics –

why are discs broad at 0.1 Eddington?Thursday 16th June 2016 Tim Roberts - Summary talk 14


Comparing discs (Sutton talk)


Evidence for outflows/winds?



Pinto talk & Nature

paper

Also optical spectra

(Fabrika, Vinokourov)

What about jets?

o Koerding – scaling XRB cores to nearby galaxies: undetectable by SKA (but lobes up to 103 times brighter?)

o But IMBHs more radio-bright – get mass using fundamental plane


Jets in IR?


Dudik et al. (submitted) –

Spitzer detection.

Bright, variable jet or circumbinary

disc?JWST science?

Where do ULS fit?o Feng – part of UL

state (SSUL regime) – highest accretion rates?n NGC 247 ULX

transit SUL to SSULn But properties could

possibly be described by wind model (me)



ULXULS

M83ULXM81ULS

From Roberto’s talk

ULSo Liu – M101 ULX1 is

classic ULS – has relativistic baryonic jets, stellar-mass BH (Nature papers) –super-Eddington!

o L ~ T-2: can’t be discs (also Urquhart & Soria etc)


Where are they found?o Many ULXs located near star formation (Swartz talk)

o Relationship: LX/1039 erg s-1 ≈ 2-6 × SFR (M¤ yr-1)o More ULXs seen in low metallicity galaxies (Brorby,

Mapelli) n Bigger BHs; more HMXB formationn Better survival rate of CE phase


Effect of ULX on its environment?

How do they affect environment?o Pakull – LX ~ Lmech

o Swartz – flat XLFs so few ULXs dominate LXfrom whole galaxy. n 71% of flux from ULXs (Brorby)n Their spectral shape important

o Brorby – large mean free path means X-rays escape early galaxies, warm IGM, delay re-ionisationn Quench SF in dwarf galaxies? Affect their

evolution mechanically? (Cf. missing dwarfs problem)Thursday 16th June 2016 Tim Roberts - Summary talk 22


Does this change over cosmic time?o Brorby – lower metallicity

at higher z – more ULXs!n Missed by surveys due to

curvatureo Lehmer – LHMXB/SFR ≈

(1+z)o HMXB > AGN @ z > 5o Mechanical & radiative

ULX feedback important!



Open questions

o Lags, QPOs (if real…)


X-ray/optical in Ho IX X-1 (Zampieri talk)

X-ray lags (Hernandez-Garcia et al. 2015)

Long quasi periods


80 day quasi-period

Exciting new thingso Super-Eddington

neutron star simulations (Takahashi & Mineshige)

o Emitted power: Rotating BH > NS > non-rotating BH


BH: L > LEddNS: L ~ LEdd

Mag. NS: L ≈ LEdd(Ω/2π)

Exciting new things (2)o 2 adjacent ULXs in

M51 show eclipses! (Urquhart talk)

o But have different propertiesn ULX1 in SUL regime

& radio jet, optical nebula like SS433

n ULX2 in BD regime & bubble nebula?


ULX1hardsoft

ULX2

Exciting new things (3)

0 20 40 60 80 100 120 140 160 180

O1 upper limits

rateLIGO

BH-BHonly

M1


Belczynski –new LIGO detections

(23+13 M¤, 8+14 M¤).ULXs as

progenitors? Or different population?

What else did we learn?o Strasbourg is lovely;

but it rains a loto If you’re flying KLM,

check in as early as possible

o At the conference dinner, it’s not always good to sit in the middle of a lively debate…


It’s been great

o It’s been a fantastically interesting and enjoyable workshop

o Thanks to the organisers, especially Roberto, Christian and Manfred

o Have a safe trip home


ulxs and their environments: a meeting...

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