CAMB:Isocurvature perturbations
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- Posts: 72
- Joined: June 13 2007
- Affiliation: Malaviya National Institute of Technology Jaipur
CAMB:Isocurvature perturbations
Hi,
I am running CAMB to find Cls usnig CDM isocuvature
perturbations.
I would like to know how to get Cls with correlated aidiabatic-isocurvature perturbations. I think CAMB gives cls using aidiabatic and isocruvarture perturbations seperatly.
Can any one help me in getting correlated aidiabatic-isocurvature cls?
Thanks,
Akhilesh
[/list]
I am running CAMB to find Cls usnig CDM isocuvature
perturbations.
I would like to know how to get Cls with correlated aidiabatic-isocurvature perturbations. I think CAMB gives cls using aidiabatic and isocruvarture perturbations seperatly.
Can any one help me in getting correlated aidiabatic-isocurvature cls?
Thanks,
Akhilesh
[/list]
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- Posts: 1948
- Joined: September 23 2004
- Affiliation: University of Sussex
- Contact:
Re: CAMB:Isocurvature perturbations
CAMB can get individual spectra or totally (anti-)correlated spectra with the same initial power spectrum.
To get the correlated ones set
and change
to whatever weighting of the modes you like. To get partially correlated spectra you'd need to run CAMB a few times with different inputs and combine results.
To get the correlated ones set
Code: Select all
initial_condition = 0
Code: Select all
initial_vector = -1 0 0 0 0
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- Posts: 72
- Joined: June 13 2007
- Affiliation: Malaviya National Institute of Technology Jaipur
CAMB:Isocurvature perturbations
Dear Mr. A. Lewis
I thank you for your kind help. I tried with taking initial condition=0. But I could'nt
understand the meaning of "initial_vector = -1 0 0 0 0". There are five numbers in this line.
Would you please explain me about each number?
Suppose I want to get total Cls as
[tex]Cl^{total}=(1-\alpha) Cl^{AA}+\alpha Cl^{iso}+2\beta \sqrt{\alpha (1-\alpha)}Cl^{corr}[/tex]
taking [tex]\alpha[/tex] and [tex]\beta[/tex] as 0.1 and 0.2 respectivily.
Then what numbers I have to put in initial_vector = -1 0 0 0 0?
I have taken above formula from Bean, Dunkley and Pierpaoli Phys. Rev .D 74, 063503 (2006).
Looking forward for your help.
Thanking you,
Sincerely,
Akhilesh
I thank you for your kind help. I tried with taking initial condition=0. But I could'nt
understand the meaning of "initial_vector = -1 0 0 0 0". There are five numbers in this line.
Would you please explain me about each number?
Suppose I want to get total Cls as
[tex]Cl^{total}=(1-\alpha) Cl^{AA}+\alpha Cl^{iso}+2\beta \sqrt{\alpha (1-\alpha)}Cl^{corr}[/tex]
taking [tex]\alpha[/tex] and [tex]\beta[/tex] as 0.1 and 0.2 respectivily.
Then what numbers I have to put in initial_vector = -1 0 0 0 0?
I have taken above formula from Bean, Dunkley and Pierpaoli Phys. Rev .D 74, 063503 (2006).
Looking forward for your help.
Thanking you,
Sincerely,
Akhilesh
-
- Posts: 1948
- Joined: September 23 2004
- Affiliation: University of Sussex
- Contact:
Re: CAMB:Isocurvature perturbations
The five numbers are the initial amplitudes of the different isocurvature modes (see comment in the .ini file). For definitions see the notes.