Magnetized Neutron stars
Stationary and axisymmetric
equilibrium
configurations with magnetic field
Access to the data
files
There are two magnetic field configurations in the main directory:
- Bbig is for a relatively
large amplitude of the magnetic field: the magnetic pressure over the
fluid pressure at the center of the star is about 1%.
- Bsmall is for a smaller
amplitude of the magnetic field: the magnetic pressure
over the fluid pressure at the center of the star is about 10^{-4}.
- Bpretty_small is for a
small amplitude of the magnetic field: the magnetic pressure
over the fluid pressure at the center of the star is about 10^{-8}.
- Btiny is for a very
small amplitude of the magnetic field: the magnetic pressure
over the fluid pressure at the center of the star is about 10^{-12}.
Then, in each of them there is three files and two subdirectories:
- glob_quantities.txt : is
a short text file containing the description of the magnetized star,
and of its global quantities (mass, radius, magnetic moment...) as they
have been calculated by the spectral code magstar.
- par_eos.d : the
parameters used by magstar
for the equation of state.
- parrot.d : other
parameters used by magstar
(central enthalpy, numbers of points, ...)
- Rlarge stands for the
outer radius of the grid being 2.4 times star's radius.
- Rsmall has a ratio of
1.2 between both quantities.
Finally, each subdirectory has complete sets, in tar-gzip form, for
different numbers of grid points:
- 51pts.tar.gz is for a cubic grid of size 51 x 51 x 51
- and so on...
Each *pts.tar.gz file contains
- size.d : the parameters for the exportation to the cubic
grid: first line is the number of points of the cubic grid in each
dimension, second is the ratio between the grid dimension and the
equatorial diameter of the star.
- coordinates.dat : gives a list of the x, y, z
coordinates of all grid points. This gives the order in which the grid
points are stored for the other fields, meaning that in e.g. density.dat the j^{th}
line gives the density of the j^{th} grid point which
coordinates are given by the j^{th} line of coordinates.dat.
- density.dat : the rest-mass density rho.
- velocity.dat : the
contravariant form of the coordinate velocity v^{i}.
- pressure.dat : the fluid
pressure P.
- currents.dat : the
contravariant form of the 4-currents j^{µ}.
- lapse.dat, shift.dat, metric.dat
: the information about the 4-metric in 3+1 form (shift in
contravariant and 3-metric in covariant forms).
- ext_curvature.dat : the
extrinsic curvature in covariant form.
- magnetic.dat : the
magnetic field in contravariant form.
Note
: All data are in International
Standard Units (meter, kilogram, second, Ampere), these are
recalled in the first line of each file. In particular, the magnetic
field is in Tesla: 1 Tesla = 10^{4} Gauss. All
vectors and tensors are expressed in a Cartesian triad (d/dx, d/dy,
d/dz).
Contact: Jérôme
Novak