Fixes for massive mergers and small update double_star::dump

Extended range of inversion of Hertzsprung gap core masses to relative masses > 100 to find solutions for massive mergers.
Copied "dirty fix" for mergers in which super_giants switch from TAGB to EAGB from the similar case in which they switch from EAGB to TAGB
double_star::dump now prints n_elements = 2 at start of dump, even if one of the stars is disintegrated

Author: nelemans

dstar/starclass/double_star.C

@@ -375,7 +375,8 @@ void double_star::dump(ostream & s, bool brief) {
 
       if(bin_type!=Merged) {
 
-      int n_elements = no_of_elements();
+      //int n_elements = no_of_elements(); // Gijs March26: 2 stars are printed in this dump so better to make that clear at the start of the dump
+      int n_elements = 2
 
       s << n_elements
         << "\n " << identity

sstar/starclass/hertzsprung_gap.C

@@ -206,18 +206,18 @@ real hertzsprung_gap::add_mass_to_accretor(real mdot, bool hydrogen, const real
         real t_bgb = base_giant_branch_time(relative_mass, metalicity);
         relative_age = t_ms + tau * (t_bgb - t_ms);
         last_update_age = t_ms;
-
+        
         if (tau < 0.){
             real (single_star::*fptr)(const real, real) = &single_star::initial_hertzsprung_gap_core_mass;                   
-            real m_rel = linear_function_inversion(fptr, relative_mass, core_mass, metalicity);     
+            real m_rel = linear_function_inversion(fptr, relative_mass, core_mass, metalicity, cnsts.parameters(minimum_main_sequence), 300);     
             update_relative_mass(m_rel);
             last_update_age = main_sequence_time(relative_mass, metalicity);
             relative_age = last_update_age;     
             evolve_core_mass();
         }
         if (tau > 1.){
             real (single_star::*fptr)(const real, real) = &single_star::terminal_hertzsprung_gap_core_mass;        
-            real m_rel = linear_function_inversion(fptr, relative_mass, core_mass, metalicity);     
+            real m_rel = linear_function_inversion(fptr, relative_mass, core_mass, metalicity, cnsts.parameters(minimum_main_sequence), 300);     
             update_relative_mass(m_rel);
             last_update_age = main_sequence_time(relative_mass, metalicity);
             relative_age = next_update_age;            

sstar/starclass/single_star.C

@@ -877,7 +877,6 @@ star* single_star::merge_elements(star* str) {
 
   real m_conserved = get_total_mass() + str->get_total_mass();
 
-
   if (str->get_element_type()!=Main_Sequence) {
     // adding two cores of giants together should not result in
     // rejuvenation.

sstar/starclass/super_giant.C

@@ -118,68 +118,69 @@ real super_giant::add_mass_to_accretor(real mdot, bool hydrogen, const real dt)
 
       if (relative_age < t_du_old){
 
-	//EAGB
-	//part to adjust age using the co_core_mass
-	real A_He = AGB_A_He_estimator();
-	real l_bagb = base_AGB_luminosity(relative_mass, metalicity);    
-	real t_bagb = base_AGB_time(relative_mass, metalicity);
-	relative_age = determine_age(COcore_mass, relative_mass, metalicity, A_He, t_bagb, l_bagb);
-	last_update_age = t_bagb;
-	real t_du = dredge_up_time(relative_mass, metalicity);    
+	    //EAGB
+	    //part to adjust age using the co_core_mass
+	    real A_He = AGB_A_He_estimator();
+	    real l_bagb = base_AGB_luminosity(relative_mass, metalicity);    
+	    real t_bagb = base_AGB_time(relative_mass, metalicity);
+	    relative_age = determine_age(COcore_mass, relative_mass, metalicity, A_He, t_bagb, l_bagb);
+	    last_update_age = t_bagb;
+	    real t_du = dredge_up_time(relative_mass, metalicity);    
 
-	if(relative_age < last_update_age){
-	  relative_age = last_update_age;
-	  real mco = determine_core_mass(relative_age, relative_mass, metalicity, 
+	    if(relative_age < last_update_age){
+	        relative_age = last_update_age;
+	        real mco = determine_core_mass(relative_age, relative_mass, metalicity, 
 					 A_He, t_bagb, l_bagb);
-	  if(mco >= COcore_mass && mco <= core_mass) {
-	    McL_core_mass = mco;
-	    if(!update_COcore_mass(mco)) {
-	      cerr << "Update COcore mass failed in super_giant()"<<endl;
-	    }   
-	  }
-	}
-	if(relative_age > t_du){
-	  //this should not be possible
-	  cerr<<"EAGB helium accretion add_mass_to_accretor mc_co > mc_du ?"<<endl;
-	  exit(-1);
-	}
+	        if(mco >= COcore_mass && mco <= core_mass) {
+	            McL_core_mass = mco;
+	            if(!update_COcore_mass(mco)) {
+	                cerr << "Update COcore mass failed in super_giant()"<<endl;
+	            }   
+	        } 
+	    }
+	    if(relative_age > t_du){
+	        //this should not be possible
+	        cerr<<"EAGB helium accretion add_mass_to_accretor mc_co > mc_du ?"<<endl;
+	        //exit(-1);
+            //very dirty fix for mergers
+            relative_age = t_du;
+	    }
       }
       else{
 
-	//TPAGB
-	//part to adjust age using the co_core_mass
-	real mc_du = dredge_up_core_mass(relative_mass, metalicity);
-	real lambda =  min(0.9, 0.3+0.001*pow(relative_mass, 5)); // Eq.73
-	McL_core_mass = (core_mass - mc_du) / (1 - lambda) + mc_du;
+	    //TPAGB
+	    //part to adjust age using the co_core_mass
+	    real mc_du = dredge_up_core_mass(relative_mass, metalicity);
+	    real lambda =  min(0.9, 0.3+0.001*pow(relative_mass, 5)); // Eq.73
+	    McL_core_mass = (core_mass - mc_du) / (1 - lambda) + mc_du;
 
-	real L_du = dredge_up_luminosity(relative_mass, metalicity);
-	real L_x = FGB_x_luminosity(relative_mass, metalicity);
-	real AH_He = TPAGB_AH_He_estimator();
-	real t_bagb = base_AGB_time(relative_mass, metalicity);
-	real t_du = dredge_up_time(relative_mass, metalicity);    
+	    real L_du = dredge_up_luminosity(relative_mass, metalicity);
+	    real L_x = FGB_x_luminosity(relative_mass, metalicity);
+	    real AH_He = TPAGB_AH_He_estimator();
+	    real t_bagb = base_AGB_time(relative_mass, metalicity);
+	    real t_du = dredge_up_time(relative_mass, metalicity);    
 
-	if (L_du <= L_x){
-	  relative_age = determine_age(McL_core_mass, relative_mass, metalicity, AH_He, t_du, L_du);
-	  last_update_age = t_bagb; 
-	}
-	else{
+	    if (L_du <= L_x){
+	        relative_age = determine_age(McL_core_mass, relative_mass, metalicity, AH_He, t_du, L_du);
+	        last_update_age = t_bagb; 
+	    }
+	    else{
 
-	  real q = sub_giant_q_parameter(relative_mass, metalicity);
-	  real B = sub_giant_B_factor(relative_mass);
-	  real t_inf2 = specific_time_limit(AH_He, t_du,
+	        real q = sub_giant_q_parameter(relative_mass, metalicity);
+	        real B = sub_giant_B_factor(relative_mass);
+	        real t_inf2 = specific_time_limit(AH_He, t_du,
 					    B, L_du, q);
-	  relative_age = t_inf2 - pow(McL_core_mass, 1.-q)/AH_He/B/(q-1.);
-	  last_update_age = t_bagb;
-	  
-	}
+	        relative_age = t_inf2 - pow(McL_core_mass, 1.-q)/AH_He/B/(q-1.);
+	        last_update_age = t_bagb;
+	    }
 
-	if(relative_age < t_du){
-	  //this should not be possible
-	  cerr<<"TPAGB helium accretion add_mass_to_accretor mc_co < mc_du ?"<<endl;
-	  //exit(-1);
-	  //very dirty fix for mergers
-	  relative_age = t_du;
-	}
+	    if(relative_age < t_du){
+	        //this should not be possible
+	        cerr<<"TPAGB helium accretion add_mass_to_accretor mc_co < mc_du ?"<<endl;
+	        //exit(-1);
+	        //very dirty fix for mergers
+	        relative_age = t_du;
+	    }
 //                // for now nothing, the next time evolve_element is entered, star makes the transition to the next phase  
 //            if(relative_age > next_update_age){
 //            }