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CAMB: Lower minimum wavenumber?

Posted: August 09 2006
by Aaron Fenyes
I've noticed that when it's making a matter power spectrum, CAMB (July 2006 version) will never compute wavenumbers lower than 0.1e-3. Is there a way to make it (accurately) go lower than this? I tried kicking the accuracy up one notch, but the minimum didn't change.

On a slightly related note, is it normal for CMBFAST 4.5.1 to run really slow when computing transfer functions? It definitely doesn't take more than one or two minutes to make a CMB power spectrum on my machine, but I'm pretty sure the transfer function has been running for at least half an hour with no output. (kmax and k per log. int. are both 1).

Thanks!

Re: CAMB: Lower minimum wavenumber?

Posted: August 09 2006
by Antony Lewis
For CAMB you could try editing Transfer_SaveMatterPower in modules.f90 - e.g. the value of minkh. But 10^{-4} is already quite a large scale...

CAMB: Lower minimum wavenumber?

Posted: August 10 2006
by Aaron Fenyes
Blaaah... apparently the minimum is set that high for a reason. :( Thanks for your help, though!