**New features**

- New Models:

ismdust Extinction due to silicate and graphite grains olivineabs Extinction due to olivine grains agnslim AGN super-Eddington accretion model. zkerrbb Redshifted version of kerrbb thcomp Thermally comptonized continuum convolution model. logconst Convert normalization to log units log10con Convert normalization to log10 units bwcycl Self-consistent cyclotron line model. clmass Mixing model assuming constant gravitational mass in each shell. monomass Mixing model parameterized by differences of mass densities in adjacent shells. nfwmass Mixing model with NFW gravitation potential. - Updated Models:
- Using the new 201 tabulated temperatures v3.0.9 AtomDB files
for apec models. These CEI files reduce potential interpolation
problems (see
`http://atomdb.org/interpolation/index.php`). The interpolation scheme can be switched between log and linear interpolation using xset APECLOGINTERP. Another option to reduce interpolation errors is provided by xset APECUSENEI which switches all calculation of CEI spectra through the NEI code. This is slower but can be used to check calculations. To recover the older v3.0.9 files use xset APECROOT 3.0.9_51. If you do this and also want to use NEI models then you also need to use xset NEIAPECROOT 3.0.9. - The diskline, rdblur, kdblur, kdblur2, laor, laor2, kerrconv, kerrdisk have all been sped up using a new FFT-based convolution routine.
- The xscat model has been updated to extend the range of the Rext parameter for MRN and ZDABAS options from 0-199 arcsec to 0-236 arcsec.

- Using the new 201 tabulated temperatures v3.0.9 AtomDB files
for apec models. These CEI files reduce potential interpolation
problems (see
- Major overhaul to code calculating statistics. Main visible
change is that each spectrum can have a different fit statistic but
there is only a single test statistic.
- Added support for responses which have been split into parts
with different resolution. This is very effective for responses
which have high resolution but long tails down to low energies. In
the case of the XRISM Resolve instrument this will provide speed
increases of up to an order of magnitude. Note that if a file
contains multiple response extensions then XSPEC will read and use
them all unless a response extension is specified using e.g. resp.rsp{n}.

**Bug fixes**

All bug fixes to v12.10.1 released as patches are included in v12.11.