BICEP & Planck: Estimating Polarized Galactic Dust Emission

Click For Summary
BICEP's estimation of polarized galactic dust emission relied on a 353 GHz map from the Planck collaboration, which was misinterpreted as it represents the polarization fraction of all foregrounds rather than just galactic dust. Correcting for this misinterpretation suggests that the polarized galactic dust emission could explain much of the BICEP signal. Experts are still debating the validity of the BICEP signal as true B-mode polarization of the cosmic microwave background (CMB). Upcoming results from at least six additional experiments in the next 18 months may clarify the situation. The scientific community anticipates a definitive conclusion within the next couple of years.
MTd2
Gold Member
Messages
2,019
Reaction score
25
To estimate polarized emission from the galactic dust, BICEP digitized an unpublished 353 GHz map shown by the Planck collaboration at a conference. However, it seems they misinterpreted the Planck results: that map shows the polarization fraction for all foregrounds, not for the galactic dust only (see the "not CIB subtracted" caveat in the slide). Once you correct for that and rescale the Planck results appropriately, some experts claim that the polarized galactic dust emission can account for most of the BICEP signal.

http://resonaances.blogspot.com.es/2014/05/is-bicep-wrong.html

http://news.sciencemag.org/physics/2014/05/blockbuster-big-bang-result-may-fizzle-rumor-suggests
 
Physics news on Phys.org
Yes, my understanding is that the jury is still out on whether or not the BICEP signal is really B-mode polarization of the CMB. The good news is, according to a talk I saw recently, there are at least 6 more experiments that should produce results within the next 18 months. So we should know for certain in the next 1-2 years.
 

Thread 'Questioning the timescape model'

"Supernovae evidence for foundational change to cosmological models" https://arxiv.org/pdf/2412.15143 The paper claims: We compare the standard homogeneous cosmological model, i.e., spatially flat ΛCDM, and the timescape cosmology which invokes backreaction of inhomogeneities. Timescape, while statistically homogeneous and isotropic, departs from average Friedmann-Lemaître-Robertson-Walker evolution, and replaces dark energy by kinetic gravitational energy and its gradients, in explaining...
View full post »

Similar threads

Undergrad BICEP2's Mis-Estimation: Was Not CIB Subtraction the Cause?
  • · Replies 2 ·
Replies
2
Views
1K
Analysis: Why BICEP2 & PLAnck Are in Tension
  • · Replies 17 ·
Replies
17
Views
6K