Mari Kolehmainen & Chris Done Durham University 1

Currently two methods shape of the Fe line from reflected emission continuum fitting of disc dominated spectra GX widely studied in terms of Fe line burst mode (non-piled up) spectra give a * = with i≈20° (Reis et al. 2008; Miller et al. 2008) 2

Multi-colour disc blackbody Disc emission ~80 % of the total emission in the disc dominated state Restricted to stellar-mass BHs as AGNs peak in the UV 3 log ν f(ν) log ν GX 339-4

A lot of RXTE data available all spectral states observed 4

Luminosity relates to the observed flux via where is the area of the inner disc  constant emitting area, constant disc inner radius 5 GX 339-4, (R g =GM/c 2 )

Luminosity relates to the observed flux via where is the area of the inner disc  constant emitting area, constant disc inner radius 6 GX 339-4, (R g =GM/c 2 )

Limit parameters from the mass function f M =5.8 ± 0.5M  (Hynes et al. 2003) 5.8 < M< 15 M  D > 6 kpc 45°< i < 70° The inner radius  r in 2 > 6 2 /(15 2 cos 45° ) gives an upper limit for a * 7

Disc not accurately described by simple models stress-free inner boundary condition colour-temperature correction f col relativistic effects We apply these corrections to the simple models to illustrate the effect on spin 8

Likely: M= 10 M  D= 8 kpc i= 60° 9

Max spin: M= 15 M  D= 6 kpc i= 45° 10

BHSPEC (Davis et al. 2005) N-T stress-free inner boundary condition self-consistently calculates f col and the radiative transfer through each disc annuli includes all the relativistic corrections 11

Likely: M= 10 M  D= 8 kpc i= 20° i= 40° i= 60° 12

Likely: M= 10 M  D= 8 kpc i= 20° i= 40° i= 60° 13

Likely: M= 10 M  D= 8 kpc i= 20° i= 40° i= 60° 14

15 Δθ ≈ 20°- 30°  asymmetric supernova (Fragos et al. 2010) Δθ

a * < 0.9 for any reasonable mass (<15M  ), distance (>6 kpc) and inclination (i > 45°) Lower mass and/or larger distance and/or higher inclination will give lower spin 16 Max spin: M= 15 M  D= 6 kpc i = 45°

Disc+lineDiscFe line  SN collapse models X ✔ X (a * ≤0.8)  Binary form. models X ✔ X (i≥45°) 17 Fe line?Disc?

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We constrain limit parameters from the mass function of Hynes et al. (2003): Inserting M 2 =0.166 M  and M x =15 M  gives i=45° (Muñoz-Darias et al. 2008) =5.8±0.5M  20

a * =0 a * =0.8 a * =0.7 a * =0.9 21

Specific angular momentum, described as a dimensionless parameter a * Drags the accretion disc inwards a * : R in : R g 22

We derive an upper limit of 0.9 for spin in GX Discrepancy between the two methods, Fe line spin higher (and inclination lower) than from continuum fitting Lower spin from disc spectral fitting seems more likely so Fe line profile probably not yet completely understood 23

Hard to see how disc spectral fitting is wrong! L-T 4, disc emission dominant, Fe line spin too high for supernovae collapse models ( Gammie et al. 2004) Inclination too low (big misalignment from orbit) for binary formation models 24