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International Workshop on Astronomical X-Ray Optics

International Workshop on Astronomical X-Ray Optics. Fingerprints of Superspinars in Astrophysical Phenomena Zdeněk Stuchlík and Jan Schee Institute of Physics, Faculty of Philosophy and Science, Silesian university in Opava, Czech Republic. Superspinar.

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International Workshop on Astronomical X-Ray Optics

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  1. International Workshop on Astronomical X-Ray Optics Fingerprints of Superspinars in Astrophysical Phenomena Zdeněk Stuchlík and Jan Schee Institute of Physics, Faculty of Philosophy and Science, Silesian university in Opava, Czech Republic

  2. Superspinar • String Theory suggests existence of Kerr superspinars violating the general relativistic bound on the spin of compact objects (a >1) • They could be primordial remnants of the high-energy phase of very early period of the evolution of the Universe when the effects of the String Theory were relevant [Gimon&Hořava PhLB 672(3) 2009].

  3. Superspinars and Naked Singularities • It is assumed that spacetime outside the superspinar of radius R, where the stringy effects are irrelevant, is described by the standard Kerr naked singularity geometry • The exact solution describing the interior of the superspinar is not known in the 3+1 theory, but it is expected that its extension is limited to the radius satisfying the condition 0 < R < M . • Minimal radius R=0 – keeping in consideration the whole causally well behaved region of the Kerr geometry.

  4. Near-extreme Kerr superspinar • Classical instability related to Keplerian discs because of decrease of angular momentum for both corotating and retrograde accretion • Conversion to a black hole in the era of high redshift quasars, z ≈ 2 • It is then possible to observe ultra high energy particle collisions and profiled spectral lines in the vicinity of near-extreme Kerr superspinars with extremal properties [Stuchlík et al. CQG 28(15) 2011, Stuchlík&Schee CQG 29(6) 2012]

  5. Ultra-high energy particle collisions

  6. Collisions • Consider freely falling particle with covariant energy E=m being fixed and the other constants of motion Φ and Q to be free parameters. • The equation of latitudinal motion implies (We define specific quantities: q = Q/m2 and l = Φ/m .)

  7. Centre–of–Mass energy • The CM energy of two colliding particles having 4-momenta p1μ and p2μ, rest masses m1 and m2 is given by where total 4-momentum

  8. Centre–of–Mass energy Limits on collidingparticles 2 > l > -7 Extremal efficiency for l1 = l2 = -7 The simplest case: m1=m2, q1=q2=0,l1=l2=0

  9. Centre–of–Mass energy • In the case of head-on collisions of particles freely falling from infinity along radial trajectories with fixed θ =const with particles inverted their motion near r = 0 we have

  10. Centre–of–Mass energy

  11. Escape cones of collision products • Due to enormous energy occurring in the CM local system during collisions at r = M we expect that generated particles are highly ultrarelativistic or we can directly expect generation of high-frequency photons • The created particles (photons) can be distributed isotropically in the CM system.

  12. Escape cones of collision products • Determining relative velocity of CM system in LNRF we find • We conclude that in such a case the CM system is identical with the LNRF. • The construction of light escape cones is described in details in [Stuchlík&Schee CQG 27(21) 2010]

  13. Escape cones of collision products θ = 5º θ = 45º θ = 85º Escape cones LNRF. The LNRF source at r = M. Superspinar spin a=1 + 8×10-2.

  14. Escape cones of collision products θ = 5º θ = 45º θ = 85º Escape cones LNRF. The LNRF source at r = M. Superspinar spin a=1 + 5×10-2.

  15. Escape cones of collision products θ = 5º θ = 45º θ = 85º Escape cones LNRF. The LNRF source at r = M. Superspinar spin a=1 + 10-2.

  16. Escape cones of collision products θ = 5º θ = 45º θ = 85º Escape cones LNRF. The LNRF source at r = M. Superspinar spin a=1 + 10-4.

  17. Escape cones of collision products θ = 5º θ = 45º θ = 85º Escape cones LNRF. The LNRF source at r = M. Superspinar spin a=1 + 10-7.

  18. Escape cone statistics θo=85 deg, re=M

  19. Escape cone statistics θo=45 deg, re=M

  20. Appearance of Keplerian disc

  21. a=0.998 a=1.1 Keplerian discs in the vicinity of bh (top) and susp (bottom). The observer inclination is 85º and the disc spans from rin= rms to rout= 20 M.

  22. Profiled spectral lines

  23. Profiled spectral line • Emitter is expected to be locally isotropic and monochromatic • The frequency shift is • The specific flux is

  24. Profiled spectral line • Emitter is expected to be locally isotropic and monochromatic • The frequency shift is • The specific flux is

  25. Profiled spectral lines: Keplerian ring

  26. Comparison of bh and susp profiled lines SuSp spin is a=1.1, andblack hole spin is a=0.9999. The observer inclination is θo=85° and the source radial coordinate is r = 1.2 rms.

  27. Comparison of bh and susp profiled lines SuSp spin is a=1.1, andblack hole spin is a=0.9999. The observer inclination is θo=30° and the source radial coordinate is r = 1.2 rms.

  28. Influence of radius of superspinar surface SuSp spin is a=1.1, the observer inclination is θo=85° and the source radial coordinate is r = 1.2 rms.

  29. Influence of radius of superspinar surface SuSp spin is a= 2.0, the observer inclination is θo=85° and the source radial coordinate is r = 1.2 rms.

  30. Influence of radius of superspinar surface SuSp spin is a= 1.1, the observer inclination is θo= 30° and the source radial coordinate isr = 1.2 rms.

  31. Influence of radius of superspinar surface SuSp spin is a= 2.0, the observer inclination is θo= 30° and the radial source coordinate is r = 1.2 rms

  32. Influence of radius of superspinar surface SuSp spin is a=1.1, the observer inclination is θo=85° and the radiation comes from the region between r = rmsand r =10M.

  33. Influence of radius of superspinar surface SuSp spin is a= 2.0, the observer inclination is θo=85° and the radiation comes from the region betweenr = rmsand r =10M.

  34. Influence of radius of superspinar surface SuSp spin is a=1.1, the observer inclination is θo= 30°and the radiation comes from the region between r = rmsand r =10M.

  35. Influence of radius of superspinar surface SuSp spin is a= 2.0, the observer inclination is θo= 30° and the radiation comes from the region between r = rmsand r =10M.

  36. Profiled spectral line: Keplerian disc

  37. Comparison of bh and susp disk profiled lines SuSp spin is a=1.1, bh spin is a=0.9999. The observer inclination is θo= 85° and the radiation comes from the region between r = rmsand r =10M.

  38. Comparison of bh and susp disk profiled lines SuSp spin is a=1.1, bh spin is a=0.9999. The observer inclination is θo=30° and the radiation comes from the region between r = rmsand r =10M.

  39. Influence of radius of superspinar surface SuSp spin is a=1.1, the observer inclination is θo= 85° and the radiation comes from the region between r = rmsand r =10M.

  40. Influence of radius of superspinar surface SuSp spin is a= 2.0, the observer inclination is θo= 85° and the radiation comes from the region betweenr = rmsand r =10M.

  41. Influence of radius of superspinar surface SuSp spin is a= 6.0, the observer inclination is θo= 85° and the radiation comes from the region betweenr = rmsand r =10M.

  42. Influence of radius of superspinar surface SuSp spin is a=1.1, the observer inclination is θo= 30° and the radiation comes from the region between r = rmsand r =10M.

  43. Influence of radius of superspinar surface SuSp spin is a= 2.0, the observer inclination is θo= 30° and the radiation comes from the region between r = rmsand r =10M.

  44. Influence of radius of superspinar surface SuSp spin is a= 6.0, the observer inclination is θo= 30° and the radiation comes from the region between r = rmsand r =10M.

  45. Summary • Near extreme KNS naturally enable observable ultrahigh energy processes. • Energy of observable particles created in the collisions is mainly given by energy of colliding particles.

  46. Summary • In the case of Keplerian ring, the profiled lines “split” into two parts, where the “blue” one is strongly influenced by the superspinar surface radius. • In the case of Keplerian disc, the superspinar “fingerprints” are in the shape of the profiled line and in its frequency range. • Of course, the inclination of observer plays important role too and should be known prior the analysis. • There is strong qualitative difference between profiled lines created in the field of Kerr superspinars and Kerr black holes.

  47. Thank you for your attention.

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