Understanding the simulation outputs#

Now that you’ve run your first cogsworth simulation it’s time to understand how to interpret the outputs!

Learning Goals#

By the end of this tutorial you should know how to:

[1]:

import cogsworth
import numpy as np
import astropy.units as u
import matplotlib.pyplot as plt
import pandas as pd

[2]:

# this all just makes plots look nice
%config InlineBackend.figure_format = 'retina'

plt.rc('font', family='serif')
plt.rcParams['text.usetex'] = False
fs = 24

# update various fontsizes to match
params = {'figure.figsize': (12, 8),
          'legend.fontsize': fs,
          'axes.labelsize': fs,
          'xtick.labelsize': 0.9 * fs,
          'ytick.labelsize': 0.9 * fs,
          'axes.linewidth': 1.1,
          'xtick.major.size': 7,
          'xtick.minor.size': 4,
          'ytick.major.size': 7,
          'ytick.minor.size': 4}
plt.rcParams.update(params)
pd.options.display.max_columns = 999

Let’s quickly recreate a similar population to the one in the last tutorial, but now biasing towards systems likely to create neutron stars and black holes (so that the later parts of this tutorial are more interesting 😉)

[3]:

p = cogsworth.pop.Population(100, final_kstar1=[13, 14], final_kstar2=[13, 14],
                             use_default_BSE_settings=True)
p.create_population()

Run for 100 binaries
Sampled 100 binaries
[1e-02s] Sample initial binaries
[0.2s] Evolve binaries (run COSMIC)

Integrating orbits: 100%|██████████| 119/119 [00:00<00:00, 1161.67it/s]

[0.5s] Integrate galactic orbits (run gala)
Overall: 0.7s

Initial conditions#

Though not technically and output of your simulation, the sampled initial population is useful to access for reproducibility. The initC table describes the initial conditions for the stellar evolution of every system, whilst the initial_galaxy gives the position, velocity, time and metallicity at which the system is born.

initial_binaries - Stellar initial conditions#

The initial_binaries table is an output of COSMIC and is a Pandas DataFrame with a row for each sampled system. The columns describe the binary initial conditions (e.g. initial masses) as well as stellar evolution settings (e.g. common-envelope alpha).

[4]:

p.initial_binaries

[4]:
kstar_1 kstar_2 mass_1 mass_2 porb ecc metallicity binfrac tphysf mass0_1 mass0_2 rad_1 rad_2 lum_1 lum_2 massc_1 massc_2 radc_1 radc_2 menv_1 menv_2 renv_1 renv_2 omega_spin_1 omega_spin_2 B_1 B_2 bacc_1 bacc_2 tacc_1 tacc_2 epoch_1 epoch_2 tms_1 tms_2 bhspin_1 bhspin_2 tphys neta bwind hewind alpha1 lambdaf ceflag tflag ifflag wdflag pisn ppi_co_shift ppi_extra_ml rtmsflag bhflag remnantflag fryer_mass_limit maltsev_mode maltsev_fallback maltsev_pf_prob grflag bhms_coll_flag wd_mass_lim cekickflag cemergeflag cehestarflag mxns pts1 pts2 pts3 ecsn ecsn_mlow aic ussn sigma sigmadiv bhsigmafrac polar_kick_angle mm_mu_ns mm_mu_bh beta xi acc2 epsnov eddfac gamma don_lim acc_lim bdecayfac bconst ck windflag qcflag eddlimflag LBV_flag dtp randomseed bhspinflag bhspinmag rejuv_fac rejuvflag htpmb ST_cr ST_tide rembar_massloss zsun kickflag bin_num natal_kick_1 phi_1 theta_1 mean_anomaly_1 randomseed_1 natal_kick_2 phi_2 theta_2 mean_anomaly_2 randomseed_2 qcrit_0 qcrit_1 qcrit_2 qcrit_3 qcrit_4 qcrit_5 qcrit_6 qcrit_7 qcrit_8 qcrit_9 qcrit_10 qcrit_11 qcrit_12 qcrit_13 qcrit_14 qcrit_15 fprimc_0 fprimc_1 fprimc_2 fprimc_3 fprimc_4 fprimc_5 fprimc_6 fprimc_7 fprimc_8 fprimc_9 fprimc_10 fprimc_11 fprimc_12 fprimc_13 fprimc_14 fprimc_15 phase_sn_1 phase_sn_2 inc_sn_1 inc_sn_2
0 1.0 1.0 4.698050 3.797264 17.174898 0.242255 0.030000 1.0 2827.301106 4.698050 3.797264 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 2827.301106 794680645 0 0.0 1.0 0 1 1 1 0.5 0.014 5 0 -100.000000 -100.000000 -100.000000 -100.000000 0.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 3.744726 4.083493 1.362724 0.725437
1 1.0 1.0 7.325796 3.959182 659.303111 0.145843 0.017036 1.0 7906.223993 7.325796 3.959182 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 7906.223993 462462847 0 0.0 1.0 0 1 1 1 0.5 0.014 5 1 -100.000000 -100.000000 -100.000000 -100.000000 0.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 1.822689 3.783131 1.307289 1.399754
2 1.0 1.0 22.209909 18.066209 2.017690 0.001033 0.011458 1.0 5318.706038 22.209909 18.066209 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 5318.706038 -514529300 0 0.0 1.0 0 1 1 1 0.5 0.014 5 2 97.322127 -24.636763 124.831960 -100.000000 -514529300.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.247182 4.918894 0.290235 2.632831
3 1.0 1.0 51.585165 27.155132 4401.558908 0.271034 0.006022 1.0 7705.250269 51.585165 27.155132 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0003 0.003 0.006 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 7705.250269 954140660 0 0.0 1.0 0 1 1 1 0.5 0.014 5 3 63.416925 6.800539 106.803696 333.993301 -954140660.0 179.721303 40.915287 292.643380 -100.0 7.436287e+08 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 3.893668 2.813141 1.258837 1.607091
4 1.0 1.0 3.951983 3.003154 72425.309853 0.699177 0.014759 1.0 731.789346 3.951983 3.003154 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 731.789346 -1082638121 0 0.0 1.0 0 1 1 1 0.5 0.014 5 4 -100.000000 -100.000000 -100.000000 -100.000000 0.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 4.403690 5.358024 0.702274 1.622489
... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...
95 1.0 1.0 4.174748 3.022807 1.652611 0.067768 0.008243 1.0 8381.976082 4.174748 3.022807 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 8381.976082 -823025274 0 0.0 1.0 0 1 1 1 0.5 0.014 5 95 -100.000000 -100.000000 -100.000000 -100.000000 0.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.472626 3.362548 2.240190 1.218247
96 1.0 1.0 7.136089 5.705648 3547.431919 0.220289 0.014787 1.0 7935.521312 7.136089 5.705648 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 7935.521312 1670782002 0 0.0 1.0 0 1 1 1 0.5 0.014 5 96 -100.000000 -100.000000 -100.000000 -100.000000 0.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 2.722685 4.844767 1.654927 1.298071
97 1.0 1.0 8.632751 8.593908 4.382319 0.022096 0.015533 1.0 8405.868131 8.632751 8.593908 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 8405.868131 -713627973 0 0.0 1.0 0 1 1 1 0.5 0.014 5 97 148.660836 -6.575601 348.208601 -100.000000 -713627973.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 5.424119 2.382820 2.050053 1.775458
98 1.0 1.0 49.700884 37.604461 2334.535495 0.009498 0.018127 1.0 8614.507070 49.700884 37.604461 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0003 0.003 0.006 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 8614.507070 -619207706 0 0.0 1.0 0 1 1 1 0.5 0.014 5 98 126.484524 12.444072 28.004209 308.889477 -619207706.0 93.645108 -5.015615 334.551909 -100.0 2.051889e+09 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 1.656223 4.543093 0.081508 1.153337
99 1.0 1.0 15.961007 13.816449 52.937913 0.004498 0.005887 1.0 8719.861062 15.961007 13.816449 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 8719.861062 893556274 0 0.0 1.0 0 1 1 1 0.5 0.014 5 99 1172.966666 32.163143 21.069551 -100.000000 -893556274.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 4.526432 4.432509 0.580866 0.933846

100 rows × 151 columns

You could use this table to access only binaries that particular initial conditions, e.g. taking only those with eccentric initial orbits

[5]:

p.initial_binaries[p.initial_binaries["ecc"] > 0.8]

[5]:
kstar_1 kstar_2 mass_1 mass_2 porb ecc metallicity binfrac tphysf mass0_1 mass0_2 rad_1 rad_2 lum_1 lum_2 massc_1 massc_2 radc_1 radc_2 menv_1 menv_2 renv_1 renv_2 omega_spin_1 omega_spin_2 B_1 B_2 bacc_1 bacc_2 tacc_1 tacc_2 epoch_1 epoch_2 tms_1 tms_2 bhspin_1 bhspin_2 tphys neta bwind hewind alpha1 lambdaf ceflag tflag ifflag wdflag pisn ppi_co_shift ppi_extra_ml rtmsflag bhflag remnantflag fryer_mass_limit maltsev_mode maltsev_fallback maltsev_pf_prob grflag bhms_coll_flag wd_mass_lim cekickflag cemergeflag cehestarflag mxns pts1 pts2 pts3 ecsn ecsn_mlow aic ussn sigma sigmadiv bhsigmafrac polar_kick_angle mm_mu_ns mm_mu_bh beta xi acc2 epsnov eddfac gamma don_lim acc_lim bdecayfac bconst ck windflag qcflag eddlimflag LBV_flag dtp randomseed bhspinflag bhspinmag rejuv_fac rejuvflag htpmb ST_cr ST_tide rembar_massloss zsun kickflag bin_num natal_kick_1 phi_1 theta_1 mean_anomaly_1 randomseed_1 natal_kick_2 phi_2 theta_2 mean_anomaly_2 randomseed_2 qcrit_0 qcrit_1 qcrit_2 qcrit_3 qcrit_4 qcrit_5 qcrit_6 qcrit_7 qcrit_8 qcrit_9 qcrit_10 qcrit_11 qcrit_12 qcrit_13 qcrit_14 qcrit_15 fprimc_0 fprimc_1 fprimc_2 fprimc_3 fprimc_4 fprimc_5 fprimc_6 fprimc_7 fprimc_8 fprimc_9 fprimc_10 fprimc_11 fprimc_12 fprimc_13 fprimc_14 fprimc_15 phase_sn_1 phase_sn_2 inc_sn_1 inc_sn_2
5 1.0 1.0 60.554345 10.777923 233.326578 0.898906 0.004878 1.0 7541.371960 60.554345 10.777923 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0003 0.003 0.006 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 7541.371960 240424524 0 0.0 1.0 0 1 1 1 0.5 0.014 5 5 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 -39.09056 1.316148 -100.0 -240424524.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.587731 1.266131 1.544460 1.814082
8 1.0 1.0 4.107961 3.029725 195.606429 0.865092 0.005456 1.0 6591.190013 4.107961 3.029725 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 6591.190013 -398434356 0 0.0 1.0 0 1 1 1 0.5 0.014 5 8 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 -100.0 -100.00000 -100.000000 -100.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 3.688280 4.735588 0.823290 2.055173
58 1.0 1.0 3.917696 3.112204 2092.589203 0.854026 0.005124 1.0 10193.589880 3.917696 3.112204 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 10193.589880 -476863462 0 0.0 1.0 0 1 1 1 0.5 0.014 5 58 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 -100.0 -100.00000 -100.000000 -100.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.240344 2.384137 2.167404 1.958826
67 1.0 1.0 7.990418 6.045966 48.252335 0.840629 0.007646 1.0 10986.276442 7.990418 6.045966 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 10986.276442 -1993121199 0 0.0 1.0 0 1 1 1 0.5 0.014 5 67 141.145843 2.768734 145.331644 -100.0 -1.993121e+09 -100.0 -100.00000 -100.000000 -100.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 5.232863 3.015737 0.437630 0.685202
72 1.0 1.0 4.507214 3.787655 130811.357802 0.845414 0.006159 1.0 11187.467494 4.507214 3.787655 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 11187.467494 -948618966 0 0.0 1.0 0 1 1 1 0.5 0.014 5 72 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 -100.0 -100.00000 -100.000000 -100.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 6.158249 3.491548 1.118171 1.995419 
[6]:

# an alias for the initial conditions table
p.initC

[6]:
kstar_1 kstar_2 mass_1 mass_2 porb ecc metallicity binfrac tphysf mass0_1 mass0_2 rad_1 rad_2 lum_1 lum_2 massc_1 massc_2 radc_1 radc_2 menv_1 menv_2 renv_1 renv_2 omega_spin_1 omega_spin_2 B_1 B_2 bacc_1 bacc_2 tacc_1 tacc_2 epoch_1 epoch_2 tms_1 tms_2 bhspin_1 bhspin_2 tphys neta bwind hewind alpha1 lambdaf ceflag tflag ifflag wdflag pisn ppi_co_shift ppi_extra_ml rtmsflag bhflag remnantflag fryer_mass_limit maltsev_mode maltsev_fallback maltsev_pf_prob grflag bhms_coll_flag wd_mass_lim cekickflag cemergeflag cehestarflag mxns pts1 pts2 pts3 ecsn ecsn_mlow aic ussn sigma sigmadiv bhsigmafrac polar_kick_angle mm_mu_ns mm_mu_bh beta xi acc2 epsnov eddfac gamma don_lim acc_lim bdecayfac bconst ck windflag qcflag eddlimflag LBV_flag dtp randomseed bhspinflag bhspinmag rejuv_fac rejuvflag htpmb ST_cr ST_tide rembar_massloss zsun kickflag bin_num natal_kick_1 phi_1 theta_1 mean_anomaly_1 randomseed_1 natal_kick_2 phi_2 theta_2 mean_anomaly_2 randomseed_2 qcrit_0 qcrit_1 qcrit_2 qcrit_3 qcrit_4 qcrit_5 qcrit_6 qcrit_7 qcrit_8 qcrit_9 qcrit_10 qcrit_11 qcrit_12 qcrit_13 qcrit_14 qcrit_15 fprimc_0 fprimc_1 fprimc_2 fprimc_3 fprimc_4 fprimc_5 fprimc_6 fprimc_7 fprimc_8 fprimc_9 fprimc_10 fprimc_11 fprimc_12 fprimc_13 fprimc_14 fprimc_15 phase_sn_1 phase_sn_2 inc_sn_1 inc_sn_2
0 1.0 1.0 4.698050 3.797264 17.174898 0.242255 0.030000 1.0 2827.301106 4.698050 3.797264 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 2827.301106 794680645 0 0.0 1.0 0 1 1 1 0.5 0.014 5 0 -100.000000 -100.000000 -100.000000 -100.000000 0.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 3.744726 4.083493 1.362724 0.725437
1 1.0 1.0 7.325796 3.959182 659.303111 0.145843 0.017036 1.0 7906.223993 7.325796 3.959182 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 7906.223993 462462847 0 0.0 1.0 0 1 1 1 0.5 0.014 5 1 -100.000000 -100.000000 -100.000000 -100.000000 0.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 1.822689 3.783131 1.307289 1.399754
2 1.0 1.0 22.209909 18.066209 2.017690 0.001033 0.011458 1.0 5318.706038 22.209909 18.066209 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 5318.706038 -514529300 0 0.0 1.0 0 1 1 1 0.5 0.014 5 2 97.322127 -24.636763 124.831960 -100.000000 -514529300.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.247182 4.918894 0.290235 2.632831
3 1.0 1.0 51.585165 27.155132 4401.558908 0.271034 0.006022 1.0 7705.250269 51.585165 27.155132 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0003 0.003 0.006 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 7705.250269 954140660 0 0.0 1.0 0 1 1 1 0.5 0.014 5 3 63.416925 6.800539 106.803696 333.993301 -954140660.0 179.721303 40.915287 292.643380 -100.0 7.436287e+08 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 3.893668 2.813141 1.258837 1.607091
4 1.0 1.0 3.951983 3.003154 72425.309853 0.699177 0.014759 1.0 731.789346 3.951983 3.003154 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 731.789346 -1082638121 0 0.0 1.0 0 1 1 1 0.5 0.014 5 4 -100.000000 -100.000000 -100.000000 -100.000000 0.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 4.403690 5.358024 0.702274 1.622489
... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...
95 1.0 1.0 4.174748 3.022807 1.652611 0.067768 0.008243 1.0 8381.976082 4.174748 3.022807 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 8381.976082 -823025274 0 0.0 1.0 0 1 1 1 0.5 0.014 5 95 -100.000000 -100.000000 -100.000000 -100.000000 0.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.472626 3.362548 2.240190 1.218247
96 1.0 1.0 7.136089 5.705648 3547.431919 0.220289 0.014787 1.0 7935.521312 7.136089 5.705648 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 7935.521312 1670782002 0 0.0 1.0 0 1 1 1 0.5 0.014 5 96 -100.000000 -100.000000 -100.000000 -100.000000 0.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 2.722685 4.844767 1.654927 1.298071
97 1.0 1.0 8.632751 8.593908 4.382319 0.022096 0.015533 1.0 8405.868131 8.632751 8.593908 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 8405.868131 -713627973 0 0.0 1.0 0 1 1 1 0.5 0.014 5 97 148.660836 -6.575601 348.208601 -100.000000 -713627973.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 5.424119 2.382820 2.050053 1.775458
98 1.0 1.0 49.700884 37.604461 2334.535495 0.009498 0.018127 1.0 8614.507070 49.700884 37.604461 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0003 0.003 0.006 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 8614.507070 -619207706 0 0.0 1.0 0 1 1 1 0.5 0.014 5 98 126.484524 12.444072 28.004209 308.889477 -619207706.0 93.645108 -5.015615 334.551909 -100.0 2.051889e+09 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 1.656223 4.543093 0.081508 1.153337
99 1.0 1.0 15.961007 13.816449 52.937913 0.004498 0.005887 1.0 8719.861062 15.961007 13.816449 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.0 0.5 1.0 0.0 1 1 1 1 -2 0.0 0.0 0 1 4 0 0 0.5 0.1 1 0 1 2 1 0 3.0 0.0010 0.010 0.020 2.25 1.6 1 1 265.0 -20.0 1.0 90.0 400.0 200.0 0.125 0.5 1.5 0.001 10 -2 -1 -1 1 3000 1000 3 5 0 1 8719.861062 893556274 0 0.0 1.0 0 1 1 1 0.5 0.014 5 99 1172.966666 32.163143 21.069551 -100.000000 -893556274.0 -100.000000 -100.000000 -100.000000 -100.0 0.000000e+00 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 0.095238 4.526432 4.432509 0.580866 0.933846

100 rows × 151 columns

Alternatively, these initial conditions can be used to re-run a population. You can learn more about that in this COSMIC tutorial and how to do it in cogsworth in this tutorial.

initial_galaxy - Galactic initial conditions#

The initial_galaxy attribute is an instance of a cogsworth StarFormationHistory. This class stores information on the positions, kinematics, birth times and metallicities of each star. Let’s take a look.

We could get the 3D positions

[9]:

p.initial_galaxy.positions

[9]:
$[[1.1533508,~1.0649895,~-0.25574258,~\dots,~0.7764478,~0.028771699,~-5.0880689],~ [0.18472135,~1.1533867,~-6.3876685,~\dots,~-1.2757477,~-0.32488141,~4.353285],~ [0.40919965,~-0.071830732,~-0.27518851,~\dots,~-0.6594577,~0.10887273,~0.010631858]] \; \mathrm{kpc}$

Or just a single component

[23]:

p.initial_galaxy.x[:10], p.initial_galaxy.phi[:10]

[23]:

(<Quantity [ 1.15335085,  1.06498951, -0.25574258,  7.28472223, -7.64489766,
            -1.70518192,  0.7346553 ,  3.9596299 , -2.23785822, -7.18515488] kpc>,
 <Quantity [ 0.15881184,  0.8252248 , -1.61081188,  0.373095  ,  2.81760914,
            -1.75670765, -0.0545759 , -0.05818207, -1.80723105,  2.56893795] rad>)

Or even the radial velocity

[24]:

p.initial_galaxy.v_R

[24]:
$[-1.7116426,~-1.5510922,~-3.9192676,~0.76951719,~5.2123543,~0.31964648,~0.28159615,~-0.65881305,~-6.3724559,~2.3773582,~0.70812007,~6.8196241,~3.0244098,~0.34475297,~-1.8225145,~-1.3615428,~-4.9535036,~-3.9585011,~-0.5970157,~0.82380162,~-0.46485121,~2.3157807,~0.73851165,~0.65368199,~-0.049323131,~-1.4791582,~3.992083,~2.5140303,~-1.6782768,~-0.6193763,~3.8869523,~3.9123344,~-6.1694277,~-1.7728562,~-1.2165417,~3.191768,~-2.1354848,~-5.5085099,~-4.003647,~-2.2489539,~-3.6921661,~-0.74979175,~2.7573382,~-0.30988749,~0.77270232,~3.7490165,~-0.39809548,~1.1831833,~-2.5900713,~-4.044865,~-3.0153433,~4.3356918,~0.24754298,~3.5917123,~-1.0626374,~1.7926092,~0.99867812,~0.25986858,~-1.742467,~1.1061777,~2.252732,~-3.0832581,~1.0481384,~0.66586104,~-4.46161,~0.6650415,~-2.6028115,~-4.1177389,~1.7315111,~2.6440668,~-2.8520037,~-1.9279366,~4.6809584,~-1.994432,~-0.034954185,~-0.26928074,~2.8360501,~1.9225209,~3.2217787,~-0.83553217,~-0.25505033,~6.1316224,~0.30889467,~-3.1005313,~2.2800937,~-3.4654319,~0.60988951,~2.444414,~1.3383234,~6.5743913,~-4.3127841,~2.2019902,~0.12529361,~1.4077089,~4.1653891,~-2.4174877,~0.25500586,~-1.0391727,~-3.7766333,~1.635138] \; \mathrm{\frac{km}{s}}$

You can see, for this p.sfh_model (and most models I imagine), the metallicity is correlated with the lookback time.

[12]:

fig, ax = plt.subplots()
scatter = ax.scatter(p.initial_galaxy.tau, p.initial_galaxy.Z, c=p.initial_galaxy.rho.value)
ax.set(yscale="log", xlabel=f"Lookback time [{p.initial_galaxy.tau.unit:latex}]", ylabel="Metallicity")
fig.colorbar(scatter, label=f"Galactocentric radius [{p.initial_galaxy.rho.unit:latex}]")
plt.show()
../../_images/tutorials_basics_outputs_20_0.png

One could imagine using this to select out only certain systems that formed in particular locations or at particular times.

Stellar Evolution Information#

These are the main outputs from COSMIC, each table is a pandas DataFrame which is indexed by the unique binary number. For more details on exactly what each column in the tables mean you should refer to the relevant documentation from COSMIC.

bpp - Evolutionary table#

This table has, for each binary (or single star if you kept them), a row for every key evolutionary change in the history of the binary. These are listed on the COSMIC docs but you can also just use the cogsworth translator to get a full list of them:

[13]:

from cogsworth.utils import evol_type_translator
[evol_type_translator[i]["long"] for i in range(1, len(evol_type_translator))]

[13]:

['Initial state',
 'Stellar type changed',
 'Roche lobe overflow started',
 'Roche lobe overflow ended',
 'Binary entered contact phase',
 'Binary coalesced',
 'Common-envelope started',
 'Common-envelope ended',
 'No remnant',
 'Maximum evolution time reached',
 'Binary disrupted',
 'Begin symbiotic phase',
 'End symbiotic phase',
 'Blue straggler',
 'Supernova of primary',
 'Supernova of secondary']

Here’s an example set of rows for a certain binary (I’ll cherry-pick the most complicated one in this simulations)

[14]:

n_bpp_rows = np.array([len(p.bpp.loc[i]) for i in p.bin_nums])
complicated_binary = p.bin_nums[np.argmax(n_bpp_rows)]
p.bpp.loc[complicated_binary]

[14]:
tphys mass_1 mass_2 kstar_1 kstar_2 sep porb ecc RRLO_1 RRLO_2 evol_type aj_1 aj_2 tms_1 tms_2 massc_he_layer_1 massc_he_layer_2 massc_co_layer_1 massc_co_layer_2 rad_1 rad_2 mass0_1 mass0_2 lum_1 lum_2 teff_1 teff_2 radc_1 radc_2 menv_1 menv_2 renv_1 renv_2 omega_spin_1 omega_spin_2 B_1 B_2 bacc_1 bacc_2 tacc_1 tacc_2 epoch_1 epoch_2 bhspin_1 bhspin_2 bin_num
30 0.000000 3.346758 3.280125 1 1 14.503716 2.486775 0.23148 0.531995 0.530901 1 0.000000 0.000000 297.538628 3.141252e+02 0.000000 0.000000 0.000000 0.000000 2.257264 2.232016 3.346758 3.280125 118.558016 109.749412 12733.892916 12560.922079 0.000000 0.000000 1.000000e-10 1.000000e-10 1.000000e-10 1.000000e-10 5976.438387 6056.826731 0.0 0.0 0.0 0.0 0.0 0.0 0.000000 0.000000 0.0 0.0 30
30 276.138024 3.346650 3.280110 1 1 13.928341 2.340295 0.00000 1.001368 0.901218 3 276.139935 276.137965 297.564613 3.141291e+02 0.000000 0.000000 0.000000 0.000000 5.309222 4.734580 3.346650 3.280110 208.500118 184.539179 9561.603793 9820.893812 0.000000 0.000000 1.000000e-10 1.000000e-10 1.000000e-10 1.000000e-10 980.590253 980.590253 0.0 0.0 0.0 0.0 0.0 0.0 -0.001911 0.000060 0.0 0.0 30
30 300.517503 2.811980 3.814779 1 1 14.641562 2.522334 0.00000 0.999489 0.800528 4 478.126863 176.357197 478.956468 2.100593e+02 0.000000 0.000000 0.000000 0.000000 5.163515 4.753789 2.811980 3.814779 130.895249 331.585237 8630.339051 11347.454183 0.000000 0.000000 1.000000e-10 1.000000e-10 1.000000e-10 1.000000e-10 905.935025 1026.772110 0.0 0.0 0.0 0.0 0.0 0.0 -177.609360 124.160306 0.0 0.0 30
30 301.347108 2.811980 3.814779 2 1 14.693061 2.535654 0.00000 0.919890 0.803176 2 478.956468 177.186802 478.956468 2.100593e+02 0.375444 0.000000 0.000000 0.000000 4.769011 4.786291 2.811980 3.814779 145.464131 332.710999 9220.286982 11318.447639 0.075532 0.000000 1.000000e-10 1.000000e-10 1.000000e-10 1.000000e-10 1169.568958 963.671991 0.0 0.0 0.0 0.0 0.0 0.0 -177.609360 124.160306 0.0 0.0 30
30 301.546529 2.811970 3.814782 2 1 14.713398 2.540922 0.00000 1.000107 0.803392 3 479.160622 177.385862 478.961200 2.100589e+02 0.376052 0.000000 0.000000 0.000000 5.192051 4.794205 2.811970 3.814782 138.311098 332.983634 8725.983389 11311.417426 0.075727 0.000000 1.000000e-10 1.000000e-10 1.000000e-10 1.000000e-10 903.164653 903.164653 0.0 0.0 0.0 0.0 0.0 0.0 -177.614093 124.160667 0.0 0.0 30
30 304.343311 0.933813 5.692601 3 1 47.752406 14.856817 0.00000 1.863496 0.168796 2 499.802143 45.098005 496.775451 7.693055e+01 0.376655 0.000000 0.000000 0.000000 21.198332 4.333607 2.775261 5.692601 66.249688 1238.210355 3592.648449 16521.270341 0.075919 0.000000 2.785789e-01 1.000000e-10 1.372957e+01 1.000000e-10 316.606083 5235.414810 0.0 0.0 0.0 0.0 0.0 0.0 -195.458832 259.245306 0.0 0.0 30
30 308.108632 0.412911 6.211860 3 1 192.816398 120.559840 0.00000 0.966466 0.038999 4 503.567464 37.115325 496.775451 6.267845e+01 0.406537 0.000000 0.000000 0.000000 34.166034 4.582352 2.775261 6.211860 372.510274 1714.399216 4357.695581 17428.233850 0.085140 0.000000 1.000000e-10 1.000000e-10 1.000000e-10 1.000000e-10 19.349164 5027.517162 0.0 0.0 0.0 0.0 0.0 0.0 -195.458832 270.993307 0.0 0.0 30
30 308.339047 0.412011 6.212447 4 1 192.789886 120.537830 0.00000 0.182860 0.039124 2 503.797878 37.337610 496.775451 6.266475e+01 0.408365 0.000000 0.000000 0.000000 6.459117 4.597698 2.775261 6.212447 448.534153 1720.948081 10498.612773 17415.715219 0.085685 0.000000 1.000000e-10 1.000000e-10 1.000000e-10 1.000000e-10 54.689954 4992.929854 0.0 0.0 0.0 0.0 0.0 0.0 -195.458832 271.001436 0.0 0.0 30
30 310.250458 0.411497 6.211483 7 1 192.825196 120.584403 0.00000 0.002471 0.040227 2 4.763431 39.262812 308.634442 6.268727e+01 0.408449 0.000000 0.003047 0.000000 0.087261 4.728770 0.411497 6.211483 7.247109 1771.005901 32203.355275 17296.193427 0.000000 0.000000 1.000000e-10 1.000000e-10 1.000000e-10 1.000000e-10 1767.466756 4713.372778 0.0 0.0 0.0 0.0 0.0 0.0 305.487027 270.987646 0.0 0.0 30
30 333.752555 0.411426 6.191377 7 2 193.413455 121.321563 0.00000 0.002551 0.063842 2 28.277469 63.159652 308.857168 6.315962e+01 0.393353 1.126197 0.018073 0.000000 0.090436 7.524906 0.411426 6.191377 7.534752 3404.440400 31942.346931 16144.719652 0.000000 0.223691 3.933529e-01 1.000000e-10 9.043573e-02 1.000000e-10 677.423658 2216.519219 0.0 0.0 0.0 0.0 0.0 0.0 305.475087 270.592903 0.0 0.0 30
30 333.971101 0.411426 6.190846 7 3 187.401531 115.713801 0.00000 0.002633 0.790908 2 28.496065 63.390790 308.857731 6.317218e+01 0.393213 1.148648 0.018213 0.000000 0.090465 90.323498 0.411426 6.190846 7.537788 1677.673855 31940.328513 3904.326423 0.000000 0.226973 3.932131e-01 2.521731e+00 9.046538e-02 5.857064e+01 709.627654 12.628228 0.0 0.0 0.0 0.0 0.0 0.0 305.475035 270.580310 0.0 0.0 30
30 333.976480 0.411426 6.190819 7 3 152.342676 84.812276 0.00000 0.003239 1.001043 3 28.501430 63.396169 308.857572 6.317218e+01 0.393210 1.148711 0.018216 0.000000 0.090466 92.934255 0.411426 6.190846 7.537868 1747.945172 31940.281469 3888.782472 0.000000 0.226982 3.932097e-01 2.626190e+00 9.046613e-02 6.161289e+01 27.058236 27.058236 0.0 0.0 0.0 0.0 0.0 0.0 305.475050 270.580310 0.0 0.0 30
30 333.976480 0.411426 6.190819 7 3 152.342676 84.812276 0.00000 0.003239 1.001043 7 28.501430 63.396169 308.857572 6.317218e+01 0.393210 1.148711 0.018216 0.000000 0.090466 92.934255 0.411426 6.190846 7.537868 1747.945172 31940.281469 3888.782472 0.000000 0.226982 3.932097e-01 2.626190e+00 9.046613e-02 6.161289e+01 27.058236 27.058236 0.0 0.0 0.0 0.0 0.0 0.0 305.475050 270.580310 0.0 0.0 30
30 333.976480 0.411426 1.148711 7 7 0.763592 0.061913 0.00000 0.003239 0.002445 8 28.501430 0.000000 308.857572 6.317218e+01 0.393210 1.148711 0.018216 0.000000 0.090466 0.226982 0.411426 1.148711 7.537868 398.221685 31940.281469 54363.220032 0.000000 0.000000 3.932097e-01 1.148711e+00 9.046613e-02 2.269820e-01 27.058236 27.058236 0.0 0.0 0.0 0.0 0.0 0.0 305.475050 270.580310 0.0 0.0 30
30 333.976480 0.411426 1.148711 7 7 0.763592 0.061913 0.00000 0.402318 0.632872 4 28.501430 0.000000 308.857572 1.519689e+01 0.393210 1.148711 0.018216 0.000000 0.090466 0.226982 0.411426 1.148711 7.537868 398.221685 31940.281469 54363.220032 0.000000 0.000000 3.932097e-01 1.148711e+00 9.046613e-02 2.269820e-01 27.058236 36.077648 0.0 0.0 0.0 0.0 0.0 0.0 305.475050 333.976480 0.0 0.0 30
30 349.587774 0.412713 1.116370 7 8 0.676248 0.052121 0.00000 0.463166 0.703921 2 43.617492 16.240287 304.837395 1.624025e+01 0.384376 0.643889 0.028337 0.472481 0.093001 0.222246 0.412713 1.116370 7.899412 798.771414 31873.120979 65381.946270 0.000000 0.073330 3.843760e-01 1.000000e-10 9.300096e-02 1.000000e-10 2055.492403 37141.408526 0.0 0.0 0.0 0.0 0.0 0.0 305.970282 333.347486 0.0 0.0 30
30 350.541840 0.412999 1.110000 7 8 0.666055 0.051049 0.00000 0.470586 1.000987 3 44.443703 17.194354 303.956056 1.624025e+01 0.384020 0.543494 0.028979 0.566505 0.093222 0.310894 0.412999 1.116370 7.943495 1979.348179 31879.615252 69357.563539 0.000000 0.066203 3.840202e-01 1.000000e-10 9.322210e-02 1.000000e-10 44954.251934 44954.251934 0.0 0.0 0.0 0.0 0.0 0.0 306.098137 333.347486 0.0 0.0 30
30 350.895256 0.451625 1.064303 7 8 0.603548 0.044137 0.00000 0.553387 1.843034 5 31.311456 17.542305 220.357807 1.624025e+01 0.419699 0.428001 0.031926 0.640766 0.103596 0.512945 0.451625 1.116370 11.788351 3664.378540 33378.090300 62984.617317 0.000000 0.061200 4.157010e-01 1.000000e-10 1.035959e-01 1.000000e-10 130263.836557 33558.186105 0.0 0.0 0.0 0.0 0.0 0.0 319.578335 333.347486 0.0 0.0 30
30 350.895256 0.451625 1.064303 7 8 0.603548 0.044137 0.00000 0.553387 1.843034 7 31.311456 17.542305 220.357807 1.624025e+01 0.419699 0.428001 0.031926 0.640766 0.103596 0.512945 0.451625 1.116370 11.788351 3664.378540 33378.090300 62984.617317 0.000000 0.061200 4.157010e-01 1.000000e-10 1.035959e-01 1.000000e-10 130263.836557 33558.186105 0.0 0.0 0.0 0.0 0.0 0.0 319.578335 333.347486 0.0 0.0 30
30 350.895256 0.000000 1.492645 15 8 0.000000 0.000000 0.00000 0.553387 0.990000 8 31.311456 7.846723 220.357807 1.624025e+01 0.419705 0.819961 0.031921 0.672683 0.103596 0.512945 0.451625 1.545753 11.788351 3664.378540 33378.090300 62984.617317 0.000000 0.061200 4.157010e-01 1.000000e-10 1.035959e-01 1.000000e-10 130263.836557 33558.186105 0.0 0.0 0.0 0.0 0.0 0.0 319.578335 333.347486 0.0 0.0 30
30 351.594240 0.000000 1.447840 15 9 0.000000 0.000000 -1.00000 -1.000000 0.000100 2 31.311456 8.545708 220.357807 7.846723e+00 0.000000 0.479485 0.000000 0.968355 0.103596 104.406973 0.451625 1.545753 11.788351 14262.183564 33378.090300 6200.851983 0.000000 0.042068 4.157010e-01 4.794851e-01 1.035959e-01 1.043649e+02 130263.836557 0.775681 0.0 0.0 0.0 0.0 0.0 0.0 319.583800 343.048533 0.0 0.0 30
30 351.745898 0.000000 0.630980 15 11 0.000000 0.000000 -1.00000 -1.000000 0.000100 2 31.311456 0.000000 220.357807 7.846723e+00 0.000000 0.000000 0.000000 0.000000 0.103596 0.012367 0.451625 0.604922 11.788351 23.947382 33378.090300 115331.888084 0.000000 0.012367 4.157010e-01 1.000000e-10 1.035959e-01 1.000000e-10 130263.836557 0.000005 0.0 0.0 0.0 0.0 0.0 0.0 319.583800 351.745898 0.0 0.0 30
30 2891.512981 0.000000 0.630980 15 11 0.000000 0.000000 -1.00000 -1.000000 0.000100 10 31.311456 2539.767083 220.357807 1.000000e+10 0.000000 0.000000 0.000000 0.000000 0.103596 0.012367 0.451625 0.604922 11.788351 0.000152 33378.090300 5788.021776 0.000000 0.012367 4.157010e-01 1.000000e-10 1.035959e-01 1.000000e-10 130263.836557 0.000005 0.0 0.0 0.0 0.0 0.0 0.0 319.583800 351.745898 0.0 0.0 30

Now that table was probably a little hard to parse if you’re not familiar with COSMIC or BSE output because they have numbers for each stellar type and evolutionary phase. Don’t worry, you don’t need to remember what these numbers mean because cogsworth can translate the table for you

[15]:

p.translate_tables(label_type="long", replace_columns=False)

[16]:

p.bpp.loc[complicated_binary][["tphys", "evol_type_str", "mass_1", "mass_2", "kstar_1_str", "kstar_2_str", "sep", "porb", "ecc"]]

[16]:
tphys evol_type_str mass_1 mass_2 kstar_1_str kstar_2_str sep porb ecc
30 0.000000 Initial state 3.346758 3.280125 Main Sequence Main Sequence 14.503716 2.486775 0.23148
30 276.138024 Roche lobe overflow started 3.346650 3.280110 Main Sequence Main Sequence 13.928341 2.340295 0.00000
30 300.517503 Roche lobe overflow ended 2.811980 3.814779 Main Sequence Main Sequence 14.641562 2.522334 0.00000
30 301.347108 Stellar type changed 2.811980 3.814779 Hertzsprung Gap Main Sequence 14.693061 2.535654 0.00000
30 301.546529 Roche lobe overflow started 2.811970 3.814782 Hertzsprung Gap Main Sequence 14.713398 2.540922 0.00000
30 304.343311 Stellar type changed 0.933813 5.692601 First Giant Branch Main Sequence 47.752406 14.856817 0.00000
30 308.108632 Roche lobe overflow ended 0.412911 6.211860 First Giant Branch Main Sequence 192.816398 120.559840 0.00000
30 308.339047 Stellar type changed 0.412011 6.212447 Core Helium Burning Main Sequence 192.789886 120.537830 0.00000
30 310.250458 Stellar type changed 0.411497 6.211483 Helium Main Sequence Main Sequence 192.825196 120.584403 0.00000
30 333.752555 Stellar type changed 0.411426 6.191377 Helium Main Sequence Hertzsprung Gap 193.413455 121.321563 0.00000
30 333.971101 Stellar type changed 0.411426 6.190846 Helium Main Sequence First Giant Branch 187.401531 115.713801 0.00000
30 333.976480 Roche lobe overflow started 0.411426 6.190819 Helium Main Sequence First Giant Branch 152.342676 84.812276 0.00000
30 333.976480 Common-envelope started 0.411426 6.190819 Helium Main Sequence First Giant Branch 152.342676 84.812276 0.00000
30 333.976480 Common-envelope ended 0.411426 1.148711 Helium Main Sequence Helium Main Sequence 0.763592 0.061913 0.00000
30 333.976480 Roche lobe overflow ended 0.411426 1.148711 Helium Main Sequence Helium Main Sequence 0.763592 0.061913 0.00000
30 349.587774 Stellar type changed 0.412713 1.116370 Helium Main Sequence Helium Hertsprung Gap 0.676248 0.052121 0.00000
30 350.541840 Roche lobe overflow started 0.412999 1.110000 Helium Main Sequence Helium Hertsprung Gap 0.666055 0.051049 0.00000
30 350.895256 Binary entered contact phase 0.451625 1.064303 Helium Main Sequence Helium Hertsprung Gap 0.603548 0.044137 0.00000
30 350.895256 Common-envelope started 0.451625 1.064303 Helium Main Sequence Helium Hertsprung Gap 0.603548 0.044137 0.00000
30 350.895256 Common-envelope ended 0.000000 1.492645 Massless Remnant Helium Hertsprung Gap 0.000000 0.000000 0.00000
30 351.594240 Stellar type changed 0.000000 1.447840 Massless Remnant Helium Giant Branch 0.000000 0.000000 -1.00000
30 351.745898 Stellar type changed 0.000000 0.630980 Massless Remnant Carbon/Oxygen White Dwarf 0.000000 0.000000 -1.00000
30 2891.512981 Maximum evolution time reached 0.000000 0.630980 Massless Remnant Carbon/Oxygen White Dwarf 0.000000 0.000000 -1.00000

A tad less brain-melting no?

Tip

You can change the style of these translations (between “short” and “long”) and also elect to overwrite the original columns to save memory (but you’ll only want to do that once you’re done masking probably)

If you’re more of a visual person you can also convert this whole table into an evolution cartoon with some of the cogsworth utilities. Let’s do this for the complicated binary we found

[17]:

p.plot_cartoon_binary(complicated_binary);
../../_images/tutorials_basics_outputs_32_0.png

bcm - User-specified timestep table#

The columns here are identical to the bpp table and by default, this table will only include timesteps for the start and end of the evolution of each binary (and thus we don’t save it in cogsworth in these cases). However, you can use bcm_timestep_conditions to define particular conditions that can result in finer resolution timestep conditions being printed. For example you could print extra timesteps for any binary that is transferring mass onto a compact object to look at X-ray binaries in more detail.

For more details on this check out the cogsworth tutorial on re-running binaries and the COSMIC docs about the setting the time resolution dynamically.

kick_info - Supernova kick information#

This table contains two rows per binary, displaying the info for the two potential supernova kicks that may occur for each star. The columns tell you about the magnitude and direction of the kicks as well as the impact on the systemic velocity.

Here’s the table for the systems that actually received kicks

[18]:

p.kick_info.loc[p.kick_info[p.kick_info["natal_kick"] > 0.0]["bin_num"].unique()]

[18]:
star disrupted natal_kick phi theta mean_anomaly delta_vsysx_1 delta_vsysy_1 delta_vsysz_1 vsys_1_total delta_vsysx_2 delta_vsysy_2 delta_vsysz_2 vsys_2_total theta_euler phi_euler psi_euler randomseed bin_num
2 1.0 1.0 97.322127 -24.636763 124.831960 0.000000 -50.527420 72.612968 -40.570100 97.322127 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 -5.145293e+08 2.0
2 0.0 0.0 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000e+00 2.0
3 1.0 1.0 63.416925 6.800539 106.803696 333.993301 -21.713766 69.550218 5.214060 73.047292 -0.487510 -5.310271 0.751388 5.385279 6.643533 226.651983 337.185280 -9.541407e+08 3.0
3 2.0 1.0 179.721303 40.915287 292.643380 0.000000 0.000000 0.000000 0.000000 73.047292 52.286667 -125.343078 117.707111 183.809321 0.000000 0.000000 0.000000 7.436287e+08 3.0
6 1.0 1.0 389.914739 52.900686 198.333735 0.000000 -223.257518 -73.981224 310.992545 389.914739 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 -1.725820e+09 6.0
... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ...
97 0.0 0.0 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000e+00 97.0
98 1.0 1.0 126.484524 12.444072 28.004209 308.889477 124.991380 85.662558 25.550593 153.667666 -4.957441 -5.871536 0.215610 7.687499 9.075057 97.549260 136.397753 -6.192077e+08 98.0
98 2.0 1.0 93.645108 -5.015615 334.551909 0.000000 0.000000 0.000000 0.000000 153.667666 84.235402 -40.084588 -8.187133 91.981006 0.000000 0.000000 0.000000 2.051889e+09 98.0
99 1.0 1.0 1172.966666 32.163143 21.069551 0.000000 926.573748 356.969440 624.407485 1172.966666 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 -8.935563e+08 99.0
99 0.0 0.0 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000e+00 99.0

130 rows × 19 columns

Galactic Evolution Information#

So now you know how everything started and how each binary system evolved, the last outputs now tell you the path each system took through the galaxy and where they ended.

orbits - Galactic orbits#

The full tracks are stored in orbits, there is an orbit entry for every bound binary and each disrupted primary/secondary. Because this has a slightly strange shape you can access these orbits more easily as primary_orbits and secondary_orbits, which return the orbits of the binaries for bound systems and individual stars in disrupted systems.

First let’s look at the orbit of a bound binary

[19]:

fig, ax = plt.subplots()
bound_orbits = p.primary_orbits[~p.disrupted]
np.random.choice(bound_orbits).plot(['x', 'y'], axes=[ax])
plt.show()
../../_images/tutorials_basics_outputs_40_0.png

Tip

Try changing that last cell to use secondary_orbits - you’ll note the plot looks identical because this is a bound binary and the secondary is going to follow the same track as the primary

And now let’s pick a random disrupted system

[25]:

fig, ax = plt.subplots()
random_disrupted_ind = np.random.randint(p.disrupted.sum())
p.primary_orbits[p.disrupted][random_disrupted_ind].plot(['x', 'y'], axes=[ax])
p.secondary_orbits[p.disrupted][random_disrupted_ind].plot(['x', 'y'], axes=[ax])
plt.show()
../../_images/tutorials_basics_outputs_43_0.png

final_pos,vel - Final states#

A lot of the time you might not need the full orbit and actually only care where the system is at the end of the simulation (and how it is moving). In this case you don’t need to access each orbit but can instead just use final_pos/vel. These arrays both have the same length as orbits but now with the 3 dimensions each.

[21]:

p.final_pos

[21]:
$[[0.15104624,~0.88867255,~0.3860705],~ [-0.51886291,~-0.55015936,~0.053011317],~ [0.90194748,~-1.1034721,~0.061957196],~ \dots,~ [-2.6808547,~26.575989,~-3.995192],~ [-0.38001534,~-0.30977939,~0.44174403],~ [-0.16788418,~-0.22626639,~0.079288767]] \; \mathrm{kpc}$
[22]:

p.final_vel

[22]:
$[[-149.3462,~55.419282,~22.305863],~ [44.103817,~-200.63998,~-18.509676],~ [-54.384048,~-367.78355,~38.831809],~ \dots,~ [-97.64276,~40.323027,~20.114235],~ [75.051301,~-70.854396,~8.8081498],~ [-25.360238,~-98.06608,~21.294847]] \; \mathrm{\frac{km}{s}}$

Wrap-up#

And that’s all for this one! Hopefully you now have a better understanding of the outputs of a cogsworth simulation and how to interpret them. Keep reading in the next tutorial to learn about how to save and load simulations, and check out the other tutorials to see all of the features of cogsworth!

Note

This tutorial was generated from a Jupyter notebook that can be found here.