Particle Physics with the Cosmic Microwave Background with SPT-3G Jessica Avva on behalf of the SPT-3G collaboration UC Berkeley Photo: Jason Galliccio
The Early Universe: a Particle Physics Laboratory Neutrinos Atoms < 1% 4.6% Today Dark Matter 23% ● Neutrinos account for < 1 percent ● Dark Energy dominates the universe Dark Energy 72% 2 NASA/WMAP Science Team
The Early Universe: a Particle Physics Laboratory Neutrinos Energy Density (log scale) Photons Dark Matter + Atoms Today The universe is dark energy dominated Dark Energy 10 9 10 5 1100 0 3 Redshift M. Millea
The Early Universe: a Particle Physics Laboratory Neutrinos Energy Density (log scale) Early Universe 10 The universe is matter dominated (~380,000 yrs after the Photons BIg Bang) Dark Matter + Atoms Today The universe is dark energy dominated Dark Energy 10 9 10 5 1100 0 4 Redshift M. Millea
The Early Universe: a Particle Physics Laboratory 44 Early Early Universe The universe is radiation dominated Neutrinos (~1 sec after the Big Bang Energy Density (log scale) Early Universe 10 The universe is matter dominated (~380,000 yrs after the Photons BIg Bang) Dark Matter + Atoms Today The universe is dark energy dominated Dark Energy 10 9 10 5 1100 0 5 Redshift M. Millea
The Big Picture of the Universe Observable: [now] Galaxy Surveys, tracers of large scale structure Observable: [~380,000 yrs after the Big Bang] The Cosmic Microwave Background 6
The Big Picture of the Universe Observable: [now] Galaxy Surveys, tracers of large scale structure Now: CνB neutrinos are not Beginning: Neutrinos (CνB) were relativistic, dominant Observable: [~380,000 yrs after relativistic, dominant observable observable is their effect on the Big Bang] The Cosmic is their effect on the expansion structure growth Microwave Background 7 history of the universe
Effect of Neutrinos in the Early Universe: N eff N eff corresponds to number of relativistic species in early universe - sensitive to number of neutrinos, sterile neutrinos, light dark matter, axions, etc. Standard Model prediction for 3 neutrinos = 3.046 Matter underdensity Matter overdensity 8 Z. Hou, L. Knox
Effect of Neutrinos in the Early Universe: N eff ● θ s - sound horizon ( typical overdensity / N eff corresponds to underdenisty size ) number of relativistic ● θ d - photon diffusion scale ( map smoothed species in early below this scale ) universe - sensitive to number of neutrinos, More relativistic sterile neutrinos, light species and/or dark particles (larger N eff ) = dark matter, axions, etc. increased expansion rate = increased θ s Standard Model and θ d prediction for 3 neutrinos = 3.046 Matter underdensity Matter overdensity 9 Z. Hou, L. Knox
Effect of Neutrinos in the Early Universe: N eff ● θ s - sound horizon ( typical overdensity / N eff corresponds to underdenisty size ) number of relativistic ● θ d - photon diffusion scale ( map smoothed species in early below this scale ) universe - sensitive to number of neutrinos, More relativistic sterile neutrinos, light species and/or dark particles (larger N eff ) = dark matter, axions, etc. increased expansion rate = increased θ s Standard Model and θ d prediction for 3 neutrinos = 3.046 Matter underdensity Matter overdensity 10 Z. Hou, L. Knox
Effect of Neutrino Mass on Structure Over Time ● As the universe expands, the CνB loses energy ● Neutrino velocities drop and they become bound to large structures ● Given known neutrino energy, time of transition for when neutrinos become non-relativistic determines Σm ν N. Whitehorn 11 Now Time
The SPT-3G camera on The South Pole Telescope ● 16,000 TES bolometers ● 90, 150, and 220 GHz 10m diameter ● Polarization ● 1.6, 1.2, 1.0 arcmin beams Observing 1500 deg 2 patch ● ● 2017-2023 Anderson 2018 8 arcmin NASA diameter Goddard circle 12 Huang 1907.09621
Field maps from the SPT-3G Survey Observation Strategy: Observe the SPT-3G 1500 deg 2 field every ~2 days for 6 years! 13
Extracting Particle Physics from SPT-3g Field Maps Galaxy Clusters and Power Spectrum Lensing Power →N eff Spectrum →Σ m ν 14
Extracting Particle Physics from SPT-3g Field Maps Galaxy Clusters and Power Spectrum Lensing Power →N eff Spectrum →Σ m ν 15
SPT-3G Sensitivity Comparison - EE Power Spectrum Planck SPTpol SPT-3G forecast Large angular scales Small angular scales 16
SPT-3G 2018 EE Power Spectrum Planck best-fit model SPT-3G EE Data Using 2018 150 GHz data, y SPT-3G is the most sensitive r a n measurement of the CMB EE i m polarization spectrum from 700 < i l e ℓ < 1700! r P 17 Daniel Dutcher
SPT-3G 2018 EE Power Spectrum Planck best-fit model SPT-3G EE Data N eff y r a Characterize n i m suppression i l of structure at e r P small angular scales 18 Daniel Dutcher
SPT-3G 2018 EE Power Spectrum Planck best-fit model Characterize peak SPT-3G EE Data locations at larger angular scales Characterize y r suppression a n i of structure at m i small angular l e r scales P 19 Daniel Dutcher
SPT-3G EE Power Spectrum to N eff Constraint Precision constraint of the energy density in relativistic and dark particles; search for deviations from Standard Model prediction Constraints and Forecasts for ΛCDM+Y p +N eff Cosmology Standard Model Predicted value for 3 neutrino species: N eff = 3.046 Planck constraint ΔN eff = 0.19 (1 𝜏 ) Previous constraint from SPT-3G forecast ΔN eff = 0.1 (1 𝜏 ) SPTpol + PlanckTT - 10 σ confirmation of CνB: N eff = 3.54 ± 0.54 (Henning et al, ΛCDM+Y p +N eff ) 20 https://arxiv.org/pdf/1907.04473.pdf
Extracting Particle Physics from SPT-3g Field Maps Galaxy Clusters and Power Spectrum Lensing Power →N eff Spectrum →Σ m ν 21
Two independent measurements of Σm ν with SPT-3G The CMB probes the evolution of structure over time ESA and the Planck Collaboration CMB Lensing: Measure the distortions to the CMB power spectrum by intervening matter Galaxy Clusters: Measure the between us and the surface of last scattering abundance of galaxy clusters as a function of mass and redshift 22
Two independent measurements of Σm ν with SPT-3G The CMB probes the evolution of structure over time Independent systematics ESA and the Planck Collaboration CMB Lensing: Measure the distortions to the CMB power spectrum by intervening matter Galaxy Clusters: Measure the between us and the surface of last scattering abundance of galaxy clusters as a function of mass and redshift 23
Two independent measurements of Σm ν with SPT-3G The CMB probes the evolution of structure over time Galaxy Clusters: Measure the abundance of galaxy clusters as a function of mass and redshift 24
Two independent measurements of Σm ν with SPT-3G The CMB probes the evolution of structure over time ESA and the Planck Collaboration CMB Lensing: Measure the distortions to the CMB power spectrum by intervening matter Galaxy Clusters: Measure the between us and the surface of last scattering abundance of galaxy clusters as a function of mass and redshift 25
Two independent measurements of Σm ν with SPT-3G The CMB probes the evolution of structure over time E (curl-free component): B (curl component): CMB has polarization Polarization that follows follows gradient of gradient of temperature temperature field. E field. Should NOT exist modes should exist from from just primordial T: Gaussian random primordial density density fluctuations we temperature field fluctuations we see in T. see in T. ESA and the Planck Collaboration CMB Lensing: Measure the distortions to the CMB power spectrum by intervening matter between us and the surface of last scattering 26 Hu and Okamoto 2001
Two independent measurements of Σm ν with SPT-3G The CMB probes the evolution of structure over time Adds CMB lensing non-gaussianity potential: 2-d projection of the full and polarization 3-d gravitational curl component potential between us and surface of last scattering ESA and the Planck Collaboration CMB Lensing: Measure the distortions to the CMB power spectrum by intervening matter between us and the surface of last scattering 27 Hu and Okamoto 2001
Measuring Σm ν with Galaxy Clusters and Lensing Cosmological constraint on neutrino mass at level comparable to known lower limit (~60 meV) from oscillation experiments! Neutrino oscillation experiments : Σm ν ≳ 0.058 eV Inverted Hierarchy: two neutrinos with m ν ≳ 0.058 eV, so Σm ν ≳ 0.116 eV Assuming normal hierarchy and minimum value Σm ν = 0.058 eV, SPT-3G could provide evidence against the inverted hierarchy. Assuming the inverted hierarchy, SPT-3G could rule out Σm ν = 0 at 2 sigma . 28 K. Aylor
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