HEASoft and XSPEC are now available as conda packages. See details ....
nsmax: Neutron Star Magnetic Atmosphere
This model has been superseded by nsmaxg.
This model interpolates from a grid of neutron star (NS) atmosphere
spectra to produce a final spectrum that depends on the parameters
listed below. The atmosphere spectra are obtained using the latest
equation of state and opacity results for a partially ionized,
strongly magnetized hydrogen or mid-Z element plasma. The models are
constructed by solving the coupled radiative transfer equations for
the two photon polarization modes in a magnetized medium, and the
atmosphere is in radiative and hydrostatic equilibrium. The atmosphere
models mainly depend on the surface effective temperature and
magnetic field strength
and inclination
; there is also a
dependence on the surface gravity
, where
is the gravitational redshift and
and
are the
NS mass and radius, respectively.
Two sets of models are given: one set with a single surface and
and a set which is constructed with
and
varying across the surface according to the magnetic dipole model (for
the latter,
is the angle between the direction to the
observer and the magnetic axis). The effective temperatures span the
range
for hydrogen and
for mid-Z elements. The models with single (
,
)
cover the energy range 0.05–10 keV, while the models with
(
,
)-distributions cover the range 0.09–5 keV.
par1 | |
par2 | |
par3 | switch indicating model to use |
norm |
|
The models available by setting par3 are:
Switch | Element | ||||||
1000 | H | 0.01 | 0 | N/A | 2.4 | 5.5 – 6.7 | 0.05 - 10 |
1060 | H | 0.04 | 0 | N/A | 2.4 | 5.5 – 6.7 | 0.05 - 10 |
1085 | H | 0.07 | 0 | N/A | 2.4 | 5.5 – 6.7 | 0.05 - 10 |
1100 | H | 0.1 | 0 | N/A | 2.4 | 5.5 – 6.7 | 0.05 - 10 |
1200 | H | 1.0 | 0 | N/A | 0.4 – 2.5 | 5.5 – 6.7 | 0.05 - 10 |
1230 | H | 2.0 | 0 | N/A | 2.4 | 5.5 – 6.8 | 0.05 - 10 |
1260 | H | 4.0 | 0 | N/A | 2.4 | 5.5 – 6.8 | 0.05 - 10 |
1280 | H | 7.0 | 0 | N/A | 2.4 | 5.5 – 6.8 | 0.05 - 10 |
1300 | H | 10.0 | 0 | N/A | 0.4 – 2.5 | 5.5 – 6.7 | 0.05 - 10 |
1330 | H | 20.0 | 0 | N/A | 2.4 | 5.6 – 6.8 | 0.05 - 10 |
1350 | H | 30.0 | 0 | N/A | 2.4 | 5.7 – 6.8 | 0.05 - 10 |
1211 | H | 1.26 | 0 | N/A | 1.6 | 5.5 – 6.8 | 0.05 - 10 |
1281 | H | 7.0 | 0 | N/A | 1.6 | 5.5 – 6.8 | 0.05 - 10 |
12006 | C | 1.0 | 0 | N/A | 2.4 | 5.8 – 6.9 | 0.05 - 10 |
13006 | C | 10.0 | 0 | N/A | 2.4 | 5.8 – 6.9 | 0.05 - 10 |
12008 | O | 1.0 | 0 | N/A | 2.4 | 5.8 – 6.9 | 0.05 - 10 |
13008 | O | 10.0 | 0 | N/A | 2.4 | 5.8 – 6.9 | 0.05 - 10 |
12010 | Ne | 1.0 | 0 | N/A | 2.4 | 5.8 – 6.9 | 0.05 - 10 |
13010 | Ne | 10.0 | 0 | N/A | 2.4 | 5.8 – 6.9 | 0.05 - 10 |
123100 | H | 1.0 – 1.82 | 0-90 | 0 | 1.6 | 5.5 – 6.8 | 0.09 - 5 |
123190 | H | 1.0 – 1.82 | 0-90 | 90 | 1.6 | 5.5 – 6.8 | 0.09 - 5 |
130100 | H | 5.5 – 10.0 | 0-90 | 0 | 1.6 | 5.5 – 6.8 | 0.09 - 5 |
130190 | H | 5.5 – 10.0 | 0-90 | 90 | 1.6 | 5.5 – 6.8 | 0.09 - 5 |
If you publish results obtained using nsmax, please reference Ho, Potekhin & Chabrier (2008) and also Mori & Ho (2007) if using the mid-Z models. See Ho (2014) for discussion of nsmaxg and nsmax.