English

A Library of Synthetic X-ray Spectra for Fitting Tidal Disruption Events

High Energy Astrophysical Phenomena 2022-06-30 v3

Abstract

We present a tabulated version of our slim disk model for fitting tidal disruption events (TDEs). We create a synthetic X-ray spectral library by ray-tracing stationary general relativistic slim disks and including gravitational redshift, Doppler, and lensing effects self-consistently. We introduce the library to reduce computational expense and increase access for fitting future events. Fitting requires interpolation between the library spectra; the interpolation error in the synthetic flux is generally <10%<10\% (it can rise to 40%40\% when the disk is nearly edge-on). We fit the X-ray spectra of the TDEs ASASSN-14li and ASASSN-15oi, successfully reproducing our earlier constraints on black hole mass MM_\bullet and spin aa_\bullet from full on-the-fly ray-tracing. We use the library to fit mock observational data to explore the degeneracies among parameters, finding that 1) hotter thermal disk and edge-on inclination angle spectra offer tighter constraints on MM_\bullet and aa_\bullet; 2) the constraining power of spectra on MM_\bullet and aa_\bullet increases as a power-law with the number of X-ray counts, and the index of the power law is higher for hotter thermal disk spectra; 3) multi-epoch X-ray spectra partially break the degeneracy between MM_\bullet and aa_\bullet; 4) the time-dependent level of X-ray absorption can be constrained from spectral fitting. The tabulated model and slim disk model are {\href{https://doi.org/10.25739/hfhz-xn60}{here.}

Keywords

Cite

@article{arxiv.2204.03922,
  title  = {A Library of Synthetic X-ray Spectra for Fitting Tidal Disruption Events},
  author = {Sixiang Wen and Peter G. Jonker and Nicholas C. Stone and Ann I. Zabludoff and Zheng Cao},
  journal= {arXiv preprint arXiv:2204.03922},
  year   = {2022}
}

Comments

Accepted for Publication in ApJ