Over the past few years, we have generated many different flavours of the X-ray reflection model REFLIONX, using the code of Ross & Fabian (2005). These models are now publicly available, and a full list of models is provided below. We recommend using one of the standard models, unless you are trying to replicate a specific result using one of the smaller targeted grids.

Accessing the models:
All models listed here are available anonymously from the IoA ftp: Note that most browsers no longer support ftp and you will likely need a dedicated ftp client. Alternatively, files can be downloaded from the command line using wget (e.g. "wget").

If you find that a model is missing, please let us know and we will try to track it down and upload it.

Requesting new models:

If you have a specific use case that isn't well served by the existing models, please get in touch. Depending on your needs, we should be able to generate a custom model relatively quickly.


If you use one of these models, please cite the original Ross & Fabian paper, along with the relevant paper where that specific model was introduced. We suggest a recommended citation in each case below.

List of models:

Note that all models are .fits files, regardless of file extension. I dropped the .mod file extension convention after a while, I thought it was confusing. XSPEC doesn't care either way. Please note that the specific use-case models are likely to have more limited parameter spaces, or coarser model grids, which may lead to problems in fitting.

Recommended standard models:

  • reflionx.mod - Standard REFLIONX, from Ross & Fabian 2005. No density, no cutoff energy. Suitable for low energy spectra of high mass objects. 

  • reflionx_hc.mod  - Standard REFLIONX, with a variable high energy cutoff.  This version was used for many of the early NuSTAR papers. Suggested reference: Tomsick et al. 2014

  • reflionx_HD.mod - The first regular version with a free density parameter, covering the range from 10^15 to 10^22 per cm^3. No high energy cutoff or iron abundance. Suggested reference: Tomsick et al., 2018

  • reflionx_bb.mod - This version uses a black body as the input spectrum, instead of the standard powerlaw. Note that this assumes only external illumination fron the black body (e.g. from a neutron star), not internal heating of the disk. Suggested reference: Ludlam et al., 2017

Specific models:

  • reflionx_bb_2019_RL.fits - Similar to reflionx_bb.mod, but allowing for higher densities. More restricted parameter space. Suggested reference: possibly unpublished?

  • reflionx_HD_nthcomp_v2.fits - Expanded version of v1. Uses NTHcomp as input spectrum, instead of a powerlaw, and has density as a free parameter. Suggested reference: Jiang et al., 2020Connors et al., 2021