NBODY4: Define.f

define.f from the November 2005 adaptation of Dr. Sverre Aarseth's NBODY4 for NBodyLab.org

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SUBROUTINE DEFINE * * * Definition of parameters, options & counters. * ---------------------------------------------- * * * Input parameters * **************** * * -------------------------------------------------------------------- *** * NBODY4: * * KSTART Control index (1: new run; >1: restart; 3, 4, 5: new params). * TCOMP Maximum computing time in minutes (saved in CPU). * GPID Number of boards (counting from 0). *** * INPUT: * * N Total particle number (singles + binary c.m; < NMAX - 2). * NFIX Output frequency of data save or binaries (#3 & 6). * NCRIT Final particle number (alternative termination criterion). * NRAND Random number sequence skip. * NRUN Run identification index. * * ETA Time-step parameter for total force polynomial. * DTADJ Time interval for parameter adjustment (N-body units). * DELTAT Output time interval (N-body units). * TCRIT Termination time (N-body units). * QE Energy tolerance (restart if DE/E > 5*QE & KZ(2) > 1). * RBAR Virial cluster radius in pc (set = 0 for isolated cluster). * ZMBAR Mean mass in solar units for equal-mass case (1.0 used if 0). * * KZ(J) Non-zero options for alternative paths (see table). * * DTMIN Time-step criterion for regularization search. * RMIN Distance criterion for regularization search. * ETAU Regularized time-step parameter (6.28/ETAU steps/orbit). * ECLOSE Binding energy per unit mass for hard binary (positive). * GMIN Relative two-body perturbation for unperturbed motion. * GMAX Secondary termination parameter for soft KS binaries. *** * INPUT: if(kz(4).gt.0) * * DELTAS Output interval for binary search (in TCR; #4, suppressed). * ORBITS Minimum periods for binary output (level 1). * GPRINT Perturbation thresholds for binary output (9 levels). *** * DATA: * * ALPHA Power-law index for initial mass function (used if KZ(20)<2)). * BODY1 Maximum particle mass before scaling (KZ(20): solar mass). * BODYN Minimum particle mass before scaling (also after scaling). * NBIN0 Number of primordial binaries (can be -ve: see IMF). * ZMET Metal abundance (range 0.03 - 0.0001). * EPOCH0 Evolutionary epoch (in Myr). * DTPLOT Plotting interval for HRDIAG (N-body units; >= DELTAT). *** * SETUP: if(kz(5).eq.2) * * APO Separation of two Plummer models (SEMI = APO/(1 + ECC). * ECC Eccentricity of two-body orbit (ECC < 0.999). * N2 Membership of second Plummer model (N2 <= N). * SCALE Second scale factor (>= 0.2 for limiting minimum size). * * if(kz(5).eq.3) * * APO Separation between the perturber and Sun. * ECC Eccentricity of orbit (=1 for parabolic encounter). * DMIN Minimum distance of approach (pericentre). * SCALE Perturber mass scale factor (=1 for Msun). * * if(kz(5).eq.4) * * SEMI Initial semi-major axis (changes a bit on scaling). * ECC Eccentricity (ECC > 1: NAME = 1 & 2 free-floating). * M1 Mass of first member (in units of mean mass). * M2 Mass of second member (rescaled total mass = 1). *** * SCALE: * * Q Virial ratio (Q = 0.5 for equilibrium). * VXROT XY-velocity scaling factor (> 0 for solid-body rotation). * VZROT Z-velocity scaling factor (not used if VXROT = 0). * RTIDE Unscaled tidal radius (#14 > 1; otherwise copied to RSPH2). *** * SCALE: if(kz(24).gt.0) * * X(3),V(3) Position and velocity for initial subsystems (KZ(24) lines). *** * XTRNL0: if (kz(14).eq.2) * * GMG Point-mass galaxy (solar masses, linearized circular orbit). * RG0 Central distance (in kpc). * * if (kz(14).eq.3) * GMG Point-mass galaxy (solar masses). * DISK Mass of Miyamoto disk (solar masses). * A Softening length in Miyamoto potential (in kpc). * B Vertical softening length (kpc). * VCIRC Galactic circular velocity (km/sec) at RCIRC (=0: no halo). * RCIRC Central distance for VCIRC with logarithmic potential (kpc). * RG Initial position; GMG+DISK=0, VG(3)=0: A(1+E)=RG(1), E=RG(2). * VG Initial cluster velocity vector (km/sec). * *** * HOTSYS: if(kz(29).gt.0) * * SIGMA0 Hot initial velocity in km/sec (routine HOTSYS; #29). *** * BINPOP: if(kz(8).eq.1.or.kz(8).gt.2) * * SEMI Semi-major axis in model units (all equal if RANGE = 0). * ECC Initial eccentricity (< 0 for thermal distribution). * RATIO Mass ratio M1/(M1 + M2); (= 1.0: M1 = M2 = ). * RANGE Range in SEMI for uniform logarithmic distribution (> 0). * NSKIP Binary frequency of mass spectrum (#20 < 2; body #1 first). * IDORM Indicator for dormant binaries (>0: merged components). * ICIRC Indicator for eigen-evolution (RANGE: minimum period). * (see BINPOP for further explanation of SEMI, RATIO & RANGE uses) * *** * HIPOP: if(kz(8).gt.0.and.kz(18).gt.1) * * NHI Number of primordial hierarchies. * SEMI Semi-major axis in model units (all equal if RANGE = 0). * ECC Initial eccentricity (< 0 for thermal distribution). * RATIO Mass ratio (= 1.0: M1 = M2; random in [0.5-0.9]). * RANGE Range in SEMI for uniform logarithmic distribution (> 0). * ICIRC Circularization & collision check (not implemented yet). *** * INTIDE: if(kz(27).gt.0) * * RSTAR Size of typical star in S.U. * IMS # idealized main-sequence stars. * IEV # idealized evolved stars. * RMS Scale factor for main-sequence radii (>0: fudge factor). * REV Scale factor for evolved radii (initial size RSTAR). *** * CLOUD0: if(kz(12).lt.0) * * NCL Number of interstellar clouds. * RB Boundary radius in pc. * VCL Mean cloud velocity in km/sec. * SIGMA Velocity dispersion (#12 = -2 or -3: Gaussian). * DTBIG Interval for injecting massive cloud (#12 = -2). * * CLM Cloud mass in solar units (#12 < 0; NCL members). * RCL Cloud radius (softening) in pc. *** * --------------------------------------------------------------------- * * * Options KZ(J) * ************* * * --------------------------------------------------------------------- * 1 COMMON save on unit 1 at end of run (=2: every 100*NMAX steps). * 2 COMMON save on unit 2 at output (=1); restart if DE/E > 5*QE (=2). * 3 Basic data on unit 3 at output (freq. NFIX; >1: cluster + tail). * # 4 Binary diagnostics on unit 4 (# threshold levels = KZ(4) < 10). * 5 Initial conditions (#22 =0; =0: uniform & isotropic sphere; * =1: Plummer; =2: two Plummer models in orbit, extra input; * =3: massive perturber and planetesimal disk, extra input). * =4: massive initial binary, extra input; output on unit 35). * 6 Output of significant & regularized binaries (=1, 2, 3 & 4). * 7 Lagrangian radii (>0: RSCALE; =2, 3, 4: output units 6, 7, 12; * =5: density & rms velocity at given radii on unit 26 & 27; * =6: Lagrangian radii for two mass groups on unit 31 & 32. * 8 Primordial binaries (=1 & >=3; >0: BINOUT; >2: BINDAT; >3: HIDAT). * 9 Individual bodies printed at output time (MIN(5**KZ9,NTOT)). * 10 Diagnostic KS output (>0: begin; >1: end; >=3: each step). * # 11 Synchronization of circular orbits (suppressed). * 12 Disk shocks (=1: standard model) or interstellar clouds (< 0). * 13 Scaling of time (1: variable by t_cr; 2: variable by t_r; * -1: constant scaling to t_r; -2: constant scaling to t_c). * 14 External force (=1: linearized; -1: cutoff; =2: point-mass galaxy; * =3: point-mass + disk + logarithmic halo in any combination). * 15 Triple, quad, chain (#30 > 0) or merger search (>1: full output). * 16 Updating of regularization parameters (RMIN, DTMIN & ECLOSE). * 17 Modification of ETA (>=1) & ETAU (>1) by tolerance QE. * 18 Hierarchical systems (=1: diagnostics; =2: primordial; =3: both). * 19 Stellar evolution and mass loss (=1: old supernova scheme; * =3: Eggleton, Tout & Hurley; >4: Chernoff--Weinberg). * 20 Initial mass function (=0,1: Salpeter; >1: various, see IMF). * 21 Extra output (>0: model, etc; >1: CENTRE; >2: MTRACE; >3: GLOBAL). * 22 Initial conditions on unit 10 (=1: output; =2,3(unscaled): input). * 23 Escaper removal (>1: diagnostics in file ESC; =2: angles unit #6; * >1: tidal tails output if #14 = 3). * 24 Initial conditions for subsystem (routine SCALE; KZ(24) = #). * # 25 Partial reflection of KS binary orbit (GAMMA < GMIN; suppressed). * 25 HR diagnostics of evolving stars (output of B & S on #82 & 83). * 26 Slow-down of two-body motion (=1: KS binary; =2: chain binary). * 27 Two-body interactions (-2: RADIUS = 0; -1: collision detection; * =1: sequential circ; > 0: collision). * 28 (not used). * # 29 Boundary reflection for hot system (suppressed). * 30 Chain regularization (=1: basic; >1: main output; >2: each step). * 31 Centre of mass correction after energy check. * 32 Increase of output intervals (based on single particle energy). * 33 Block-step diagnostics at main output (=2: active pipes). * # 34 Roche lobe overflow (suppressed). * 35 Time offset (global time from TTOT = TIME + DTOFF; offset = 100). * 36 Step reduction for hierarchical systems (not recommended). * 37 Step reduction for encounters with high-velocity particles. * 38 Multiple use of GRAPE-6 (sleep 1 sec after each timer check). * 39 Neighbour list (=-1: on host; =0: full list or closest on GRAPE). * 40 (not used). * --------------------------------------------------------------------- * # currently suppressed * --------------------------------------------------------------------- * * * Output counters * *************** * * --------------------------------------------------------------------- * NBCALL Neighbour lists (# NBLIST calls). * NBESC Escaped binaries (#23). * NBLOCK Block integration steps. * NBKICK Binary neutron star kicks (#19). * NBPREV Indicator for enforcing new KS scheduling (SUBINT). * NBREF Boundary reflections (#29; suppressed). * NBSTAT Diagnostic data on binary interactions (#4; inactive). * NCBLK1 Active binary steps on HARP. * NCBLK2 Active binary steps with more than one pipe. * NCHAIN Chain regularizations (#30). * NCOLL Stellar collisions (#27). * NDIAG Diagnostic warning counter (BRAKE, IMPACT & SPIRAL). * NDISS Tidal dissipation at pericentre (#27). * NDUMP Restart counter (STOP after two restarts). * NHIVEL High-velocity search for all particles (#37). * NHLIST Neighbour lists on HARP (not implemented). * NIRECT Initialization of NSTEPI after exceeding 2*10**9. * NKICK Neutron star kicks (#19). * NKSHYP Hyperbolic KS regularizations. * NKSMOD Slow KS motion restarts (#26). * NKSPER Unperturbed KS binary orbits. * NKSREF Partial reflections of KS binary (#25; suppressed). * NKSREG Total KS regularizations. * NKSTRY Two-body regularization attempts. * NMERG Mergers of stable triples or quadruples (#15). * NMESC Escaped mergers (#15 and 23). * NMTRY Attempted mergers. * NPRECT Initialization of NKSPER after exceeding 2*10**9. * NPRINT Output counter (data bank written at NFIX, then reset). * NQUAD Four-body regularizations (#15). * NSESC Escaped single particles (#23). * NSHOCK Tidal shocks (#12). * NSHORT Shortened time-step due to high-velocity particles (#37). * NSPERT Membership of perturber list (set in routine SIEVE). * NSTEPC Chain regularization steps (# DIFSY calls). * NSTEPI Irregular integration steps (reset to zero at 2*10**9). * NSTEPQ Quadruple regularization integration steps (#15). * NSTEPS Total number of time-steps (reset to zero at 2*10**9). * NSTEPT Triple regularization integration steps (#15). * NSTEPU Regularized integration steps. * NSYNC Number of synchronous binaries (e < 0.002; #27). * NTIDE Tidal captures from hyperbolic orbits (#27). * NTIMER Time-step counter (reset to zero on checking CPU time). * NTPERT Perturbation time-scale evaluations (includes NBLIST calls). * NTRECT Time rectifications (not implemented yet). * NTRIP Three-body regularizations (#15). * NTTRY Search for triple, quad & chain regularization or mergers. * NURECT Initialization of NSTEPU after exceeding 2*10**9. * NWARN Warning messages (only first 1000 printed). * --------------------------------------------------------------------- * * Counters in COMMON/STAR/ * ************************ * * --------------------------------------------------------------------- * NMDOT Calls to routine MDOT. * NMS Main sequence stars (type 0/1). * NHG Hertzsprung gap (type 2). * NRG Red giants (type 3). * NHE Helium burning (type 4). * NRS red supergiants (type 5). * NWD White dwarfs (type 8). * NSN Neutron stars (type 9). * NHI High-velocity stars (r < 3*). * NDD Doubly generate binaries (type >= 8). * NBS Blue stragglers (type 1). * NTZ Thorne-Zytkow objects (type 9 + 0/1 -> 9). * NAS Accretion-induced supernovae (Roche; M2 > MCH; type 12). * NBH Black holes (type 10). * NGB Gamma-ray bursters. * NROCHE Calls to routine ROCHE. * NRO Completed Roche stages. * NBR Blue Roche (TM < TPHYS & type 0/1). * NBRK Calls to routine BRAKE (GR & MB). * NCONT Contact binaries (Roche; enforced collisions). * NCOAL Coalescence of binaries (Roche; giant collisions). * NHYP Hyperbolic collisions & coalescence. * NSPIR Calls to routine SPIRAL. * NSP Circularization events. * NCIRC Successful circularizations. * NSLP Inactive circularizations (TC > 2x10**9 yr). * NEWHI New hierarchical systems (counted by routine HIARCH). * NEINT Runge-Kutta integration steps for eccentricity modulation. * NGLOB0 Initial membership of globular cluster model. * NGLOB Current membership. * NSHOCK Tidal shocks. * --------------------------------------------------------------------- * * * Stellar evolution types * *********************** * * --------------------------------------------------------------------- * 0 Low main sequence (M < 0.7). * 1 Main sequence. * 2 Hertzsprung gap (HG). * 3 Red giant. * 4 Core Helium burning. * 5 First AGB. * 6 Second AGB. * 7 Helium main sequence. * 8 Helium HG. * 9 Helium GB. * 10 Helium white dwarf. * 11 Carbon-Oxygen white dwarf. * 12 Oxygen-Neon white dwarf. * 13 Neutron star. * 14 Black hole. * 15 Massless supernova remnant. * --------------------------------------------------------------------- * RETURN * END

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