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functions in cosmo.i - l

 
 
 
ldist


              ldist(z,q0=,lambda0=)  
 
   Compute the term to integrate to compute the luminosity  
   distance. z can be a VECTOR of values.  
     
   KEYWORDS: q0      : Deceleration parameter,numeric scalar  
                       -a*(a'')/(a')^2 (Omega_m/2-lambda0)  
                          
             lambda0 : Cosmological constant, normalized to  
                       th closure density.  
     
interpreted function, defined at ./cosmo.i   line 104  
SEE ALSO: lumdist  
 
 
 
lumdist


             lumdist(z,h0=,k=,lambda0=,Omega_m=,q0=,silent=)  
 
   See IDL routine...  
   PURPOSE:   
     Calculate luminosity distance (in Mpc) of an object given its redshift   
   EXPLANATION:  
     The luminosity distance in the Friedmann-Robertson-Walker model is   
     taken from  Caroll, Press, and Turner (1992, ARAA, 30, 499), p. 511  
     Uses a closed form (Mattig equation) to compute the distance when the   
     cosmological constant is zero.   Otherwise integrates the function using  
     simpson_cosmo.	  
   EXAMPLE:  
     Plot the distance of a galaxy in Mpc as a function of redshift out  
     to z = 5.0, assuming the default cosmology (Omega_m=0.3, Lambda = 0.7,  
     H0 = 70 km/s/Mpc)  
       
     z = span(0,5,50);  
     plg,lumdist(z),z;  
     xytitles,"z","Distance (Mpc)"  
    
interpreted function, defined at ./cosmo.i   line 162  
SEE ALSO: ldist