Difference between revisions of "Forecastfiso planck"
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Cl^{tot} = Cl^{ad} + f_iso^2 Cl^{cdm iso} + 2* f_iso * Cl^{correlated} | Cl^{tot} = Cl^{ad} + f_iso^2 Cl^{cdm iso} + 2* f_iso * Cl^{correlated} | ||
| − | where Cl^{cdm iso} is generated such that it has the same primordial power A_s as the scalar perturbations, and similarly for Cl^{correlated}. | + | where Cl^{cdm iso} is generated such that it has the same primordial power A_s as the scalar perturbations, and similarly for Cl^{correlated}. And the anti-correlated CDM modes contributes to the total spectrum in an analogous way. |
| + | |||
| + | == Forecast == | ||
| + | Cosmology used in the forecast LCDM + f_iso. Fiducial value of f_iso=0. Use lensed TT/EE/TE spectra. | ||
| + | |||
| + | === Correlated CDM isocurvature === | ||
| + | * vary beam | ||
| + | [[File: isocorr_varybeam.png |700px]] | ||
| + | |||
| + | * vary noise | ||
| + | [[File: isocorr_varynoise.png |700px]] | ||
| + | |||
| + | * fixed effort | ||
| + | [[File: isocorr_fixedeffort.png |700px]] | ||
| + | |||
| + | |||
| + | === Anti-correlated CDM isocurvature === | ||
| + | * vary beam | ||
| + | [[File: isoanti_varybeam.png |700px]] | ||
| + | |||
| + | * vary noise | ||
| + | [[File: isoanti_varynoise.png |700px]] | ||
| + | |||
| + | * fixed effort | ||
| + | [[File: isoanti_fixedeffort.png |700px]] | ||
| + | |||
| + | |||
== Planck test == | == Planck test == | ||
Latest revision as of 20:45, 2 June 2016
Contents
Overview
We can improve constraints on isocurvature perturbations from Planck with observations from S4.
Here we consider the curvaton model: there is one isocurvature mode: the CDM isocurvature, and the spectral index of the CDM mode is the same as that of the adiabatic scalar perturbations, n_s. In this scenario, the CDM mode is either totally correlated or anti-correlated with the adiabatic perturbations.
The parameter we are constraining is f_iso, the primordial fraction of CDM isocurvature amplitude to the scalar perturbation amplitude. Specifically, the final spectra is
Cl^{tot} = Cl^{ad} + f_iso^2 Cl^{cdm iso} + 2* f_iso * Cl^{correlated}
where Cl^{cdm iso} is generated such that it has the same primordial power A_s as the scalar perturbations, and similarly for Cl^{correlated}. And the anti-correlated CDM modes contributes to the total spectrum in an analogous way.
Forecast
Cosmology used in the forecast LCDM + f_iso. Fiducial value of f_iso=0. Use lensed TT/EE/TE spectra.
- vary beam
- vary noise
- fixed effort
- vary beam
- vary noise
- fixed effort
Planck test
To check that we are getting reasonable results, we run the Fisher matrix with LCDM+Mnu+f_iso with Planck noise levels, beams, and fsky as specified in previous forecast checks.
We tested for fiducial cosmology f_iso=0 with 100% correlated CDM isocurvature modes; The following constraints use TT/EE/TE lensed spectra.
The following are the constraints we get:
| LCDM+Mnu+f_iso=0 | |
| och2 | 0.001523 |
| obh2 | 0.000163 |
| onuh2 | 0.005396 |
| 10^9 As | 0.2589 |
| ns | 0.00486 |
| tau | 0.0597 |
| hubble | 4.84 |
| f_iso | 0.00391 |
We are doing a literature search to find previous forecasts that uses a similar parameterization (as opposed to the alpha or beta parameterization) to compare our results.
