Need WMAP error bars for CMBFAST power spectrum output

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SUMMARY

The discussion centers on generating WMAP error bars for CMBFAST power spectrum outputs in the context of cosmological models, particularly adiabatic Cold Dark Matter (CDM) models. Participants highlight the necessity of using a Fisher matrix for proper error assignment in CMB angular power spectra, referencing FORTRAN90 code available for computing likelihoods against WMAP data. Key resources provided include links to NASA's Lambda website for likelihood calculations and additional data sources for CMB analysis.

PREREQUISITES
  • Understanding of CMBFAST software for generating power spectrum plots
  • Familiarity with Fisher matrix methodology in cosmological data analysis
  • Knowledge of WMAP and COBE missions and their significance in cosmic microwave background research
  • Basic concepts of adiabatic Cold Dark Matter (CDM) models
NEXT STEPS
  • Explore the implementation of Fisher matrix calculations in cosmological models
  • Learn about the specifics of CMBFAST and its capabilities for power spectrum generation
  • Investigate the significance of WMAP and COBE data in current cosmological research
  • Review the provided FORTRAN90 code for likelihood computations and adapt it for personal use
USEFUL FOR

Astronomers, cosmologists, and researchers involved in analyzing cosmic microwave background data, particularly those working with CMBFAST and seeking to compare results with WMAP and COBE findings.

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From Kosmoi.com/Science/Cosmology/http://kosmoi.com/Science/Cosmology/Big_Bang/wiki.shtml

"A critical further prediction was that the further away one looks, the hotter the universe should appear to be (as looking further away corresponds to looking backwards in time), and at some extremely distant point the radiation in the universe should be so thick as to become opaque."

AND

"In 1989, NASA launched the Cosmic Background Explorer satellite (COBE), and the initial findings (released in 1990) were a stunning endorsement of the Big Bang predictions regarding CMBR, finding a local residual temperature of 2.726 K, determining that the CMBR was indeed isotropic, and confirming the "haze" effect as distance increased."

Even without the CMB, wouldn't this effect still exist since the farther we look out into space the more matter we have to look threw? Kinda like how tape looks transparent when it is off the roll but becomes more opaque when its on the roll. Or how lake water looks clear in your hand but green in the lake.

Does the haze effect that is caused by the CMB have an official name?Also, can we see far out enough into space to find the opaque barrier that they predicted to exist? Does this barrier have a name? How do they know that the barrier isn't just a consequence of looking threw tons and tons of matter?
 
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CMB lower multipoles and geometry constraints

In recent analysis of the microwave background (e.g. that one which lead to the dodecahedral model) it is argued that, if the power spectrum of the lower multipoles shows some kind of suppression, this may be due to some geometrical condition, like the impossibility for the big fluctuations to take place completely in a curved universe.

My question is the following: since the first peak in the cmb corresponds with a fluctuation with horizon size during recombination, why should not this fluctuation be also affected by this power suppression?

With other words: how should I imagine the observable universe during recombination in an hypotetical curved or closed universe? If it should be also a curved shape, then I would say the first peak might be -more or less- affected by this suppression, since the first peak spanned the whole observable universe. Only higher multipoles should remain unaffected.

But if it should be a 'flat' patch into a big curved shape, then I would say the first peak may be unaffected.

Please some help for a qualitative understanding. Thanks.
 
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Need WMAP reference points for CMBFAST power spectrum output

I'm using CMBFAST to generate binned temperature power spectrum plots for an adiabatic CDM model, but reference points with error bars (for comparison to WMAP, COBE, etc.) aren't being generated. Does anyone have any suggestions?

Found this today: "Proper assignment of errors to points in the CMB angular power spectra requires the use of a Fisher matrix. Since some components that go into making the Fisher matrix are model dependent, we provide FORTRAN90 code which, given an input CMB model power spectrum, will compute the likelihood of that model fit to WMAP data and optionally return the Fisher matrix." -- http://lambda.gsfc.nasa.gov/product/map/current/likelihood.cfm

These look promising: http://lambda.gsfc.nasa.gov/product/map/current/m_sw.cfm, and http://lambda.gsfc.nasa.gov/product/cobe/cgis_docs.cfm

I found some other interesting (although somewhat outdated) data here: http://bubba.ucdavis.edu/~knox/radpack.html and here
http://space.mit.edu/home/tegmark/cmb/experiments.html
 
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