I Will the upcoming experiment PICO measure kSZ temperature anisotropy?

AI Thread Summary
PICO is set to measure polarization anisotropies with high fidelity and will produce full-sky Compton-y maps, primarily focusing on low-multipole B modes critical for cosmology. The satellite's angular resolution suggests it can measure kSZ temperature anisotropy at l=3000, with E-mode anisotropies plotted up to around 4000. However, the B-mode polarization signal is significantly smaller and affected by noise, particularly due to lensing of large-scale structure mixing E and B modes. Effective measurement of B modes requires multiple frequency bands and strong control of systematic errors. Overall, while PICO will provide valuable data, the high multipoles may not yield useful information for B-mode analysis.
SherLOCKed
Messages
13
Reaction score
1
I know for sure PICO will be measuring polarization anisotropies with high fidelity. In addition, the PICO science paper shows that it will make full-sky Compton-y maps but the plots are mostly limited to l=1000. Will PICO be able to measure kSZ temperature anisotropy at l=3000?
 
Space news on Phys.org
Based upon the described angular resolution of the satellite, absolutely. For E-mode anisotropies. Indeed, if you look at Fig 2.1, you see they've plotted the E-mode anisotropies up to around 4000. But those aren't the primary focus, as the low-multipole B modes are the most critical for new cosmology. What's important for measuring those are:
1) Lots of frequency bands (this requires a satellite)
2) Good control of systematic errors for polarization

The high multipoles are swamped by noise for the B-mode polarization signal, as the B-mode polarization signal is much smaller than the E-mode signal. One of the limiting factors here is that for B-mode polarization, lensing of large scale structure mixes E and B modes, which creates a noise-like signal (this is the "lensing residual"). The instrument noise will still be below this threshold, but we just don't get useful information out of the B-mode spectrum above a hundred or so.
 
Abstract The Event Horizon Telescope (EHT) has significantly advanced our ability to study black holes, achieving unprecedented spatial resolution and revealing horizon-scale structures. Notably, these observations feature a distinctive dark shadow—primarily arising from faint jet emissions—surrounded by a bright photon ring. Anticipated upgrades of the EHT promise substantial improvements in dynamic range, enabling deeper exploration of low-background regions, particularly the inner shadow...
Back
Top