diff --git a/source/nodes.property_extractor.lightcone.F90 b/source/nodes.property_extractor.lightcone.F90 index 94b2d61964..e4504bc8df 100644 --- a/source/nodes.property_extractor.lightcone.F90 +++ b/source/nodes.property_extractor.lightcone.F90 @@ -274,7 +274,7 @@ function lightconeExtract(self,node,time,instance) & ) lightconeExtract (8 )=self%geometryLightcone_%solidAngle()/degreesToRadians**2 if (self%includeObservedRedshift) then - ! Compute the relativistic velocity β=v/c. + ! Compute the line-of-sight peculiar velocity divided by the speed of light: β_los=v_los/c. velocityBeta =+Dot_Product (lightconeExtract(4:6),lightconeExtract(1:3)) & & /Vector_Magnitude( lightconeExtract(1:3)) & & *kilo & @@ -282,16 +282,12 @@ function lightconeExtract(self,node,time,instance) ! Compute the observed redshift. This is given by: ! 1 + zₒ = (1 + zₕ) (1 + zₚ), ! where zₒ is observed redshift, zₕ is cosmological redshift (due to Hubble expansion), and zₚ is the peculiar redshift, - ! given by - ! 1 + zₚ = √[(1+βₚ)/(1-βₚ)] - ! where βₚ=vₚ/c is the dimensionless peculiar velocity (e.g. Davis et al.; 2011; ApJ; 741; 67; eqn. 4; + ! given by (in the non-relativistic limit) zₚ = β_los + ! (e.g. Davis et al.; 2011; ApJ; 741; 67; below eqn. 4; ! https://ui.adsabs.harvard.edu/abs/2011ApJ...741...67D). lightconeExtract(self%redshiftObservedOffset +1)= -1.0d0 & & + (+1.0d0 +lightconeExtract(7 )) & - & *sqrt( & - & +(+1.0d0+velocityBeta) & - & /(+1.0d0-velocityBeta) & - & ) + & * (+1.0d0 + velocityBeta ) end if if (self%includeAngularCoordinates) then lightconeExtract(self%angularCoordinatesOffset+1)=atan2( &