CAMB: the dimension of Hz in recfast.f90

[Xin Wang]

Hi, Antony,

As in the "Arguments" of recfast.f90 from the latest version of CAMB, we know within this subroutine,

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!CA     H is Hubble constant in units of 100 km/s/Mpc
...
!CA	  Hz is the value of H at the specific z (in ION)

and afterwards, Hz is assigned a value via,

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Hz = 1/dtauda(1/(1._dl+z))*(1._dl+z)**2/MPC_in_sec 

However, if I'm not mistaken, dtauda, which is defined in equations.f90, has a dimension of Mpc. Thus, Hz given by the above calculation does not have the dimension of 100 km/s/Mpc. Does this problem has some side effects on other related calculations?

BTW, I suggest using the following way to output the right Hz

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Hz = 1/dtauda(1/(1._dl+z))*(1._dl+z)**2*c/100000.

[Antony Lewis]

I think it has SI units, compare with the original Recfast code if in doubt.

[Xin Wang]

I think it has SI units, compare with the original Recfast code if in doubt.

and it has the value of H(z)=100h, rather than h itself. right?