This library provides a set of routines for solving the Tolman-Oppenheimer-Volkoff equations to determine the structure of spherically symmetric neutron stars. The provided example main program is set to compute a sequence of cold neutron stars with the MDI equation of state (EOS).
To compile the code use the provided Makefile.
$ ./tov.x
M R k2 lambda I beta rhoc
0.095584 118.842947 0.000174 411.212712 0.088190 0.001188 0.090000
0.115570 37.401989 0.000485 3.546640 0.063674 0.004563 0.104242
0.141874 24.443580 0.002786 2.429058 0.076745 0.008572 0.118485
0.172160 19.555189 0.008374 2.392401 0.094947 0.013002 0.132727
0.205533 17.109337 0.017010 2.491670 0.117936 0.017741 0.146970
0.241186 15.700874 0.027527 2.624197 0.144121 0.022686 0.161212
0.279000 14.805391 0.038857 2.761774 0.173609 0.027830 0.175455
0.318700 14.200695 0.050045 2.887528 0.206049 0.033144 0.189697
0.360015 13.774456 0.060483 2.996552 0.241145 0.038599 0.203939
0.402888 13.462845 0.069870 3.087393 0.279219 0.044196 0.218182
0.446953 13.230006 0.077968 3.157417 0.319559 0.049892 0.232424
0.491876 13.052303 0.084789 3.209142 0.362209 0.055654 0.246667
0.537403 12.913845 0.090169 3.235551 0.406190 0.061458 0.260909
0.583306 12.803477 0.094525 3.249390 0.452209 0.067282 0.275152
0.629378 12.713576 0.097675 3.241430 0.499033 0.073110 0.289394
0.675679 12.638367 0.099919 3.218964 0.547618 0.078955 0.303636
0.721829 12.574468 0.101268 3.180799 0.596756 0.084777 0.317879
0.767636 12.518908 0.101800 3.127492 0.645739 0.090557 0.332121
0.812937 12.469469 0.101867 3.068217 0.695186 0.096281 0.346364
0.857593 12.424468 0.101332 2.997423 0.745698 0.101938 0.360606
0.901487 12.382578 0.100261 2.916090 0.793749 0.107518 0.374848
0.944520 12.342838 0.098932 2.831550 0.842291 0.113013 0.389091
0.986609 12.304514 0.097316 2.742336 0.889726 0.118416 0.403333
1.026746 12.267937 0.095532 2.652284 0.935445 0.123601 0.417576
1.065893 12.231683 0.093543 2.558908 0.980620 0.128694 0.431818
1.104132 12.195328 0.090900 2.449889 1.024148 0.133708 0.446061
1.141433 12.158766 0.089184 2.367831 1.066946 0.138641 0.460303
1.177775 12.121734 0.086873 2.271541 1.108885 0.143492 0.474545
1.213141 12.084191 0.084566 2.177210 1.149402 0.148260 0.488788
1.247518 12.046012 0.081757 2.071832 1.188368 0.152945 0.503030
1.280896 12.007291 0.079813 1.990286 1.226369 0.157543 0.517273
1.313270 11.967951 0.077421 1.899217 1.263056 0.162056 0.531515
1.344639 11.927992 0.075084 1.811340 1.297964 0.166483 0.545758
1.375004 11.887436 0.072718 1.724645 1.331815 0.170823 0.560000
1.405636 11.844552 0.070368 1.639003 1.365573 0.175261 0.574242
1.436031 11.800196 0.067980 1.553962 1.398699 0.179724 0.588485
1.465301 11.755852 0.065622 1.472088 1.430650 0.184079 0.602727
1.493414 11.711608 0.063325 1.394032 1.460909 0.188319 0.616970
1.520349 11.667593 0.061190 1.321916 1.489901 0.192439 0.631212
1.546097 11.623734 0.059119 1.253344 1.517135 0.196437 0.645455
1.570657 11.580092 0.057108 1.188142 1.542898 0.200309 0.659697
1.594038 11.536654 0.055187 1.126802 1.566850 0.204056 0.673939
1.616257 11.493443 0.053344 1.068938 1.589534 0.207679 0.688182
1.637334 11.450455 0.051583 1.014461 1.610555 0.211177 0.702424
1.657298 11.407690 0.049766 0.960592 1.629588 0.214553 0.716667
1.676181 11.365178 0.048181 0.912783 1.647598 0.217809 0.730909
1.694015 11.322905 0.046791 0.870101 1.664282 0.220948 0.745152
1.710837 11.280898 0.045341 0.827608 1.679409 0.223973 0.759394
1.726684 11.239168 0.043955 0.787580 1.693074 0.226887 0.773636
1.741594 11.197717 0.042620 0.749684 1.705157 0.229694 0.787879
1.754836 11.158864 0.041419 0.715999 1.714895 0.232246 0.802121
1.767245 11.120384 0.040299 0.684711 1.724419 0.234697 0.816364
1.778945 11.081987 0.039205 0.654695 1.732195 0.237070 0.830606
1.789965 11.043656 0.038159 0.626285 1.739942 0.239366 0.844848
1.800332 11.005408 0.037141 0.599101 1.745311 0.241589 0.859091
1.810073 10.967215 0.036167 0.573330 1.750520 0.243742 0.873333
1.819217 10.929131 0.035238 0.548979 1.754275 0.245828 0.887576
1.827788 10.891144 0.034360 0.526053 1.758007 0.247847 0.901818
1.835812 10.853258 0.033425 0.502907 1.761101 0.249804 0.916061
1.843312 10.815505 0.032649 0.482741 1.762120 0.251700 0.930303
1.850313 10.777887 0.031871 0.463103 1.763076 0.253538 0.944545
1.856836 10.740424 0.031080 0.443819 1.763589 0.255319 0.958788
1.862903 10.703100 0.030360 0.426053 1.762745 0.257047 0.973030
1.868534 10.665971 0.029647 0.408876 1.761495 0.258721 0.987273
1.873750 10.629013 0.028956 0.392478 1.759891 0.260346 1.001515
1.878569 10.592243 0.028300 0.377000 1.757705 0.261921 1.015758
1.883008 10.555682 0.027673 0.362330 1.755032 0.263449 1.030000
1.887085 10.519332 0.027042 0.348017 1.751648 0.264932 1.044242
1.890818 10.483205 0.026449 0.334576 1.747952 0.266371 1.058485
1.894220 10.447295 0.025883 0.321844 1.743839 0.267768 1.072727
1.897307 10.411629 0.025332 0.309648 1.739343 0.269123 1.086970
1.900094 10.376207 0.024761 0.297557 1.734383 0.270438 1.101212
1.902594 10.341031 0.024245 0.286454 1.729184 0.271715 1.115455
1.904822 10.306114 0.023797 0.276446 1.723406 0.272955 1.129697
1.906787 10.271451 0.023314 0.266309 1.717494 0.274159 1.143939
1.908503 10.237049 0.022859 0.256767 1.711586 0.275327 1.158182
1.909983 10.202911 0.022405 0.247504 1.704867 0.276463 1.172424
1.911235 10.169055 0.021975 0.238748 1.698113 0.277565 1.186667
1.912271 10.135470 0.021565 0.230451 1.691061 0.278636 1.200909
1.913100 10.102165 0.021123 0.222049 1.683853 0.279676 1.215152
1.913733 10.069138 0.020763 0.214714 1.676564 0.280686 1.229394
1.914179 10.036388 0.020360 0.207146 1.669421 0.281667 1.243636
1.914445 10.003932 0.020018 0.200393 1.661429 0.282621 1.257879
1.914542 9.971757 0.019677 0.193837 1.653463 0.283547 1.272121
1.914474 9.939867 0.019331 0.187398 1.645540 0.284446 1.286364
1.914253 9.908267 0.019000 0.181280 1.637302 0.285321 1.300606
1.913883 9.876960 0.018681 0.175440 1.629288 0.286170 1.314848
1.913374 9.845939 0.018363 0.169765 1.620574 0.286995 1.329091
1.912729 9.815198 0.018065 0.164418 1.612226 0.287797 1.343333
1.911958 9.784761 0.017778 0.159314 1.603663 0.288576 1.357576
1.911064 9.754595 0.017489 0.154320 1.595223 0.289333 1.371818
1.910055 9.724728 0.017190 0.149372 1.586620 0.290068 1.386061
1.908935 9.695145 0.016952 0.145077 1.577513 0.290782 1.400303
1.907711 9.665863 0.016700 0.140780 1.568872 0.291476 1.414545
1.906387 9.636855 0.016449 0.136591 1.560058 0.292151 1.428788
1.904968 9.608125 0.016185 0.132408 1.551511 0.292806 1.443030
1.903458 9.579681 0.015969 0.128717 1.542428 0.293443 1.457273
1.901863 9.551532 0.015742 0.125035 1.533678 0.294061 1.471515
1.900187 9.523655 0.015516 0.121452 1.524656 0.294662 1.485758
1.898433 9.496059 0.015306 0.118082 1.515743 0.295246 1.500000
!=====================================================================
! MAIN PROGRAM
!=====================================================================
program tov2019
use eos
use constants
use terminate
use profile
implicit none
real(8) :: rhoc
real(8) :: rho_start
real(8) :: rho_end
real(8) :: rho_tmp
real(8) :: rho_h
integer(4) :: nsteps
integer(4) :: i
character(len=30) :: eos_file
external tov_derivs, y_deriv, rkqc
! +++ Parameters +++
eos_file = 'eos_MDI_x0.0.in' ! EOS
rho_start = 0.09d0 ! Starting density
rho_end = 1.5d0 ! Ending density
nsteps = 100 ! Number of density steps
! +++ End Parameters +++
rho_h = (rho_end - rho_start) / dfloat( nsteps - 1 )
rho_tmp = rho_start
100 format(1x,t10,a,t22,a,t35,a,t46,a,t62a,t73,a,t86,a)
write(6,100) 'M', 'R', 'k2', 'lambda', 'I', 'beta', 'rhoc'
! +++ Loop over central density +++
do i = 1, nsteps
rhoc = rho_tmp * fm3cm3
call solve_tov(eos_file, rhoc)
rho_tmp = rho_tmp + rho_h
enddo
end program tov2019