RELXILL is a brand new model, joining forces of the XILLVER reflection code (link; Garcia et al., 2010, 2011, 2013) and the RELLINE code (Dauser et al., 2010, 2013). The striking new feature is that for each point on the disk the proper xillver-reflection spectrum is chosen for each relativistically calculated emission angle. The implications of this improvement and more details regarding the model are provided in Garcia & Dauser et al. (2014, ApJ, 782, 76) and Dauser & Garcia et al. (2014, MNRAS, 444, L100). See also this pdf for a short information on all models and their parameters. A full list of changes of previous versions can be found here.
v0.4a: A bug was found in the
reflection fraction in v0.3a. Any reflection fraction obtained with
v0.3a can therefore unfortunately not be trusted and has to be
re-computed with new version . We would like to stress that this does
not affect the spectral shape, but only the value of the reflection
fraction obtained from the fit. The only exception is if the reflected
and primary spectrum was fixed using fixReflFrac=1 and
therefore also the complete spectral shape was affected by this
Along with the fix of the reflection fraction, the normalization of relxill was also revised. It is now consistently set to follow the xillver normalization, but including all relativistic effects. Additionally the angleon parameter was removed from the parameter list (setting it to angleon=1).
Due to several misunderstandings, the definition of the reflection fraction was revised. In order to provide a concise and detailed overview, this was done as a research note (submitted to A&A). It can be found here: http://arxiv.org/abs/1601.03771.
By installing the new RELXILL model, all previous implementations of the relline-like and relconv-like models are automatically installed, too. These models are completely identical to the ones from the RELLINE installation (hence, no additional installation of relline is necessary to get the previous functionalities).
Usage and ParametersThe RELXILL model now includes by default the irradiating power law source. It's strength can be set by the parameter refl_frac. This reflection fraction is defined as the ratio of photons that hit the disk to those that reach infinity. Due to strong light bending effects, this value can easily be larger than 1. More details can be found in Dauser+2014. Note, that for a negative value of refl_frac, only the reflection compontent will be returned (similar to the pexrav model definition). The detailed definition of the reflection fraction can be found here (Research Note accepted for publication in A&A): http://arxiv.org/abs/1601.03771. All information about the parameters of all relxill flavor models can also be found in this pdf: download
|norm:||defined as the normalization of xillver, including relativistic effects|
|refl_frac:||reflection fraction: see RN for details (differences in the exact definition between relxill and relxilllp, as it depends on the geometry)|
|Ecut:||cutoff energy in keV (the same for the power law and the reflection spectrum)|
|1: take angles properly into account|
|fixReflFrac:||0: free reflection fraction (determined by the refl_frac parameter)|
|1: fix reflection fraction to the lamp post value (i.e., the parameter refl_frac has NO meaning in this case)|
|2: free, (same as 1:), but now the reflection fraction is displayed on the screen|
The meaning of the parameters is the same as for the separate models (see relline description). Moreover, as the angular effects are properly treated, no "guess" regarding a limb brightening or darkening law is needed anymore.
To install, please download the following files:
|last changes||in version|
|tables.fits.tgz (warning: 849MB)||2016-01-18||v0.4a|
The installation is similar to the relline model (look here). Note that you can use the environment variable RELLINE_TABLES to point to the complete set of provided tables, including the xillver table.
A Comparison between RELXILL and the angle averaged approach
The code here is still in BETA-test! Please contact me if you find bugs or encounter problems with the model.