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Description
The Cosmic Microwave Background (CMB) has provided precise information on the evolution of the Universe and the current cosmological paradigm. The CMB has not yet provided definitive information on the origin and strength of any primordial magnetic fields or how they affect the presence of magnetic fields observed throughout the cosmos. This work outlines an alternative method to investigating and identifying the presence of cosmic magnetic fields. This method searches for Faraday Rotation (FR) and specifically uses polarized CMB photons as back-light. I find that current generation CMB experiments may be not sensitive enough to detect FR but next generation experiments should be able to make highly significant detections. Identifying FR with the CMB will provide information on the component of magnetic fields along the line of sight of observation.
The 21cm emission from the hyperfine splitting of neutral Hydrogen in the early universe is predicted to provide precise information about the formation and evolution of cosmic structure, complementing the wealth of knowledge gained from the CMB.
21cm cosmology is a relatively new field, and precise measurements of the Epoch of Reionization (EoR) have not yet been achieved. In this work I present 2σ upper limits on the power spectrum of 21cm fluctuations (Δ²(k)) probed at the cosmological wave number k from the Donald C. Backer Precision Array for Probing the Epoch of Reionization (PAPER) 64 element deployment. I find upper limits on Δ²(k) in the range 0.3 < k < 0.6 h/Mpc to be (650 mK)², (450 mK)², (390 mK)², (250 mK)², (280mK)², (250 mK)² at redshifts z = 10.87, 9.93, 8.91, 8.37, 8.13 and 7.48 respectively
Building on the power spectrum analysis, I identify a major limiting factor in detecting the 21cm power spectrum.
This work is concluded by outlining a metric to evaluate the predisposition of redshifted 21cm interferometers to foreground contamination in power spectrum estimation. This will help inform the construction of future arrays and enable high fidelity imaging and
cross-correlation analysis with other high redshift cosmic probes like the CMB and other upcoming all sky surveys. I find future
arrays with uniform (u,v) coverage and small spectral evolution of their response in the (u,v,f) cube can minimize foreground leakage while pursuing 21cm imaging.
The 21cm emission from the hyperfine splitting of neutral Hydrogen in the early universe is predicted to provide precise information about the formation and evolution of cosmic structure, complementing the wealth of knowledge gained from the CMB.
21cm cosmology is a relatively new field, and precise measurements of the Epoch of Reionization (EoR) have not yet been achieved. In this work I present 2σ upper limits on the power spectrum of 21cm fluctuations (Δ²(k)) probed at the cosmological wave number k from the Donald C. Backer Precision Array for Probing the Epoch of Reionization (PAPER) 64 element deployment. I find upper limits on Δ²(k) in the range 0.3 < k < 0.6 h/Mpc to be (650 mK)², (450 mK)², (390 mK)², (250 mK)², (280mK)², (250 mK)² at redshifts z = 10.87, 9.93, 8.91, 8.37, 8.13 and 7.48 respectively
Building on the power spectrum analysis, I identify a major limiting factor in detecting the 21cm power spectrum.
This work is concluded by outlining a metric to evaluate the predisposition of redshifted 21cm interferometers to foreground contamination in power spectrum estimation. This will help inform the construction of future arrays and enable high fidelity imaging and
cross-correlation analysis with other high redshift cosmic probes like the CMB and other upcoming all sky surveys. I find future
arrays with uniform (u,v) coverage and small spectral evolution of their response in the (u,v,f) cube can minimize foreground leakage while pursuing 21cm imaging.
ContributorsKolopanis, Matthew John (Author) / Bowman, Judd (Thesis advisor) / Mauskopf, Philip (Thesis advisor) / Lunardini, Cecilia (Committee member) / Chamberlin, Ralph (Committee member) / Vachaspati, Tanmay (Committee member) / Arizona State University (Publisher)
Created2018
Description
Chiral symmetry and its anomalous and spontaneous breaking play an important role
in particle physics, where it explains the origin of pion and hadron mass hierarchy
among other things.
Despite its microscopic origin chirality may also lead to observable effects
in macroscopic physical systems -- relativistic plasmas made of chiral
(spin-$\frac{1}{2}$) particles.
Such plasmas are called \textit{chiral}.
The effects include non-dissipative currents in external fields that could be present
even in quasi-equilibrium, such as the chiral magnetic (CME) and separation (CSE)
effects, as well as a number of inherently chiral collective modes
called the chiral magnetic (CMW) and vortical (CVW) waves.
Applications of chiral plasmas are truly interdisciplinary, ranging from
hot plasma filling the early Universe, to dense matter in neutron stars,
to electronic band structures in Dirac and Weyl semimetals, to quark-gluon plasma
produced in heavy-ion collisions.
The main focus of this dissertation is a search for traces of chiral physics
in the spectrum of collective modes in chiral plasmas.
I start from relativistic chiral kinetic theory and derive
first- and second-order chiral hydrodynamics.
Then I establish key features of an equilibrium state that describes many
physical chiral systems and use it to find the full spectrum of collective modes
in high-temperature and high-density cases.
Finally, I consider in detail the fate of the two inherently chiral waves, namely
the CMW and the CVW, and determine their detection prospects.
The main results of this dissertation are the formulation of a fully covariant
dissipative chiral hydrodynamics and the calculation of the spectrum of collective
modes in chiral plasmas.
It is found that the dissipative effects and dynamical electromagnetism play
an important role in most cases.
In particular, it is found that both the CMW and the CVW are heavily damped by the usual
Ohmic dissipation in charged plasmas and the diffusion effects in neutral plasmas.
These findings prompt a search for new physical observables in heavy-ion collisions,
as well as a revision of potential applications of chiral theories in
cosmology and solid-state physics.
in particle physics, where it explains the origin of pion and hadron mass hierarchy
among other things.
Despite its microscopic origin chirality may also lead to observable effects
in macroscopic physical systems -- relativistic plasmas made of chiral
(spin-$\frac{1}{2}$) particles.
Such plasmas are called \textit{chiral}.
The effects include non-dissipative currents in external fields that could be present
even in quasi-equilibrium, such as the chiral magnetic (CME) and separation (CSE)
effects, as well as a number of inherently chiral collective modes
called the chiral magnetic (CMW) and vortical (CVW) waves.
Applications of chiral plasmas are truly interdisciplinary, ranging from
hot plasma filling the early Universe, to dense matter in neutron stars,
to electronic band structures in Dirac and Weyl semimetals, to quark-gluon plasma
produced in heavy-ion collisions.
The main focus of this dissertation is a search for traces of chiral physics
in the spectrum of collective modes in chiral plasmas.
I start from relativistic chiral kinetic theory and derive
first- and second-order chiral hydrodynamics.
Then I establish key features of an equilibrium state that describes many
physical chiral systems and use it to find the full spectrum of collective modes
in high-temperature and high-density cases.
Finally, I consider in detail the fate of the two inherently chiral waves, namely
the CMW and the CVW, and determine their detection prospects.
The main results of this dissertation are the formulation of a fully covariant
dissipative chiral hydrodynamics and the calculation of the spectrum of collective
modes in chiral plasmas.
It is found that the dissipative effects and dynamical electromagnetism play
an important role in most cases.
In particular, it is found that both the CMW and the CVW are heavily damped by the usual
Ohmic dissipation in charged plasmas and the diffusion effects in neutral plasmas.
These findings prompt a search for new physical observables in heavy-ion collisions,
as well as a revision of potential applications of chiral theories in
cosmology and solid-state physics.
ContributorsRybalka, Denys (Author) / Shovkovy, Igor (Thesis advisor) / Lunardini, Cecilia (Committee member) / Timmes, Francis (Committee member) / Vachaspati, Tanmay (Committee member) / Arizona State University (Publisher)
Created2019
Description
As a demonstration study of low-resolution spectrophotometry, the photometric redshift estimation with narrow-band optical photometry of nine galaxy clusters is presented in this thesis. A complete data reduction process of the photometryusing up to 16 10nm wide narrow-band optical filters from 490nm − 660nm are provided. Narrow-band photometry data are combined with broad-band photometry (SDSS/Pan-STARRS) for photometric redshift fitting. With available spectroscopic
redshift data from eight of the fields, I evaluated the fitted photometric redshift results and showed that combining broad-band photometric data with narrow-band data result in improvements of factor 2-3, compared to redshift estimations from
broad-band photometry alone. With 15 or 16 narrow-band data combined with SDSS (Sloan Digital Sky Survey) or Pan-STARRS1 (The Panoramic Survey Telescope and Rapid Response System) data, a Normalized Median Absolute Deviation of σNMAD ∼ 0.01−0.016 can be achieved.
The multiband images of galaxy cluster ABELL 611 have been used to further study intracluster light around its brightest cluster galaxy (BCG). It can be shown here that fitting of BCG+ICL stellar properties using the averaged 1-dimensional
radial profile is possible up to ∼ 100kpc within this cluster. The decreasing in age of the stellar population as a function of radius from the BCG+ICL profile, though not entirely conclusive, demonstrates possible future application of low-resolution
spectrophotometry on the ICL studies.
Finally, Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer (SPHEREx) mission planning study are covered, and a methodology of visualization tool for target availability is described.
ContributorsWang, Pao-Yu (Author) / Mauskopf, Philip (Thesis advisor) / Butler, Nathaniel (Committee member) / Jansen, Rolf (Committee member) / Vachaspati, Tanmay (Committee member) / Arizona State University (Publisher)
Created2022