| 73 | [[BR]] |

| 74 | |

| 75 | == Connecting With NEQ Cooling == |

| 76 | One component of the cooling rate calculated by NEQ cooling is called metal_loss. This is the energy loss due to metal excitation, and it is based on the ionization fraction and DM cooling curve. Z cooling passes the parameter iCooling to the subroutine Cool_Derivatives. Now, if iCooling==ZCool, metal_loss will be subtracted from the cooling rate, and it is going to be replaced by a different rate. |

| 77 | |

| 78 | Back in the main cooling file cooling.f90, ZCoolingRate calculates the rate due to forbidden line emission. It is based on temperature, electron density, and ionization fraction. In the ZCoolingStrength subroutine, the metal_loss and ZCoolingRate are combined to give a weighted cooling rate. This is done by a parabolic weight function which I have called Zweight. The purpose of this weighted rate is to make the transition from NEQ cooling to Z cooling smooth. |

| 79 | |

| 80 | The table for ZCoolingRate is currently from 2000 to 16,500 K. Regular NEQ cooling will only cool effectively to about 8000 K or so. So you need to use Z cooling if you need to look at cooling below about 1e4 K. |

| 81 | |

| 302 | |

| 303 | For Non-equilibrium (NEQ) cooling, the length scale had to be adjusted. The shock velocity is the same as the DM case, but the cell length is now 7.75e11 cm. |

| 304 | |

| 305 | || NEQ Cooling || |

| 306 | || [[Image(NEQ_temp0010.png, width=400)]] || |

| 307 | ||= [attachment:NEQ_temp.gif Temperature Movie] =|| |

| 308 | |

| 309 | Z Cooling has the same initial parameters and scaling as the NEQ case. |

| 310 | |

| 311 | || Z Cooling || |

| 312 | || [[Image(Z_temp0010.png, width=400)]] || |

| 313 | ||= [attachment:Z_temp.gif Temperature Movie] =|| |