
'''
constants and unit conversion factors
'''

# for unit conversions
Mpc_cm = 3.086e24  # [mpc > cm]
kpc_cm = 3.086e+21  # [kpc > cm]
kpc_m = 3.086e+19  # [kpc > m]
cm_m = 1.*10**-2.  # [cm > m]
Mpc_kpc = 10**3.  # [Mpc > kpc]
km_Mpc = 3.24078e-20  # [km > Mpc]
m_kpc = 3.24078e-20  # [m > kpc]
cm_kpc = 3.24078e-22  # [cm > kpc]
joule_kev = 6.242e+15   # joule>kev
Msun_kg = 1.989e30  # [Msun > kg]
kg_Msun = 1./Msun_kg  # [kg > Msun]

# constants
Msun = 1.989e30  # [kg]
mA = 1.661e-27  # [kg], atomic mass unit
G = 6.6743e-11  # [m^3 kg^-1 s^-2]
kB = 1.38e-23  # [m^2 kg s^-2 K^-1]