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View article: MeV Cosmic-Ray Electrons Modify the TeV Pair-beam Plasma Instability
MeV Cosmic-Ray Electrons Modify the TeV Pair-beam Plasma Instability Open
Relativistic pair beams created in the intergalactic medium (IGM) by TeV gamma rays from blazars are expected to produce a detectable GeV-scale electromagnetic cascade, but the cascade component is absent in the spectra of many hard-spectr…
View article: Reionization relics in the cross-correlation between the Lyα forest and 21 cm intensity mapping in the post-reionization era
Reionization relics in the cross-correlation between the Lyα forest and 21 cm intensity mapping in the post-reionization era Open
The tumultuous effects of ultraviolet photons that source cosmic reionization, the subsequent compression and shock-heating of low-density regions, and the modulation of baryons in shallow potential wells induced by the passage of ionizati…
View article: Reionization relics in the cross-correlation between the Ly$α$ forest and 21 cm intensity mapping in the post-reionization era
Reionization relics in the cross-correlation between the Ly$α$ forest and 21 cm intensity mapping in the post-reionization era Open
The tumultuous effects of ultraviolet photons that source cosmic reionization, the subsequent compression and shock-heating of low-density regions, and the modulation of baryons in shallow potential wells induced by the passage of ionizati…
View article: Compton Scattering of Electrons in the Intergalactic Medium
Compton Scattering of Electrons in the Intergalactic Medium Open
This paper investigates the distribution and implications of cosmic-ray electrons within the intergalactic medium (IGM). Utilizing a synthesis model of the extragalactic background, we evolve the spectrum of Compton-included cosmic rays. T…
View article: Simulating image coaddition with the Nancy Grace Roman Space Telescope – II. Analysis of the simulated images and implications for weak lensing
Simulating image coaddition with the Nancy Grace Roman Space Telescope – II. Analysis of the simulated images and implications for weak lensing Open
One challenge for applying current weak lensing analysis tools to the Nancy Grace Roman Space Telescope is that individual images will be undersampled. Our companion paper presented an initial application of Imcom – an algorithm that build…
View article: Simulating image coaddition with the <i>Nancy Grace Roman Space Telescope –</i> I. Simulation methodology and general results
Simulating image coaddition with the <i>Nancy Grace Roman Space Telescope –</i> I. Simulation methodology and general results Open
The upcoming Nancy Grace Roman Space Telescope will carry out a wide-area survey in the near-infrared. A key science objective is the measurement of cosmic structure via weak gravitational lensing. Roman data will be undersampled, which in…
View article: Compton scattering of electrons in the intergalactic medium
Compton scattering of electrons in the intergalactic medium Open
This paper investigates the distribution and implications of cosmic ray electrons within the intergalactic medium (IGM). Utilizing a synthesis model of the extragalactic background, we evolve the spectrum of Compton-included cosmic rays. T…
View article: A synthetic <i>Roman Space Telescope</i> High-Latitude Time-Domain Survey: supernovae in the deep field
A synthetic <i>Roman Space Telescope</i> High-Latitude Time-Domain Survey: supernovae in the deep field Open
NASA will launch the Nancy Grace Roman Space Telescope (hereafter Roman) in the second half of this decade, which will allow for a generation-defining measurement of dark energy through multiple probes, including Type Ia supernovae (SNe Ia…
View article: Lyman-α polarization from cosmological ionization fronts. Part I. Radiative transfer simulations
Lyman-α polarization from cosmological ionization fronts. Part I. Radiative transfer simulations Open
In this paper, we present the formalism of simulating Lyman- α emission and polarization around reionization ( z = 8) from a plane-parallel ionization front. We accomplish this by using a Monte Carlo method to simulate the production of a …
View article: Lyman-α polarization from cosmological ionization fronts. Part II. Implications for intensity mapping
Lyman-α polarization from cosmological ionization fronts. Part II. Implications for intensity mapping Open
This is the second paper in a series whose aim is to predict the power spectrum of intensity and polarized intensity from cosmic reionization fronts. After building the analytic models for intensity and polarized intensity calculations in …
View article: Simulating image coaddition with the Nancy Grace Roman Space Telescope: I. Simulation methodology and general results
Simulating image coaddition with the Nancy Grace Roman Space Telescope: I. Simulation methodology and general results Open
The upcoming Nancy Grace Roman Space Telescope will carry out a wide-area survey in the near infrared. A key science objective is the measurement of cosmic structure via weak gravitational lensing. Roman data will be undersampled, which in…
View article: Simulating image coaddition with the Nancy Grace Roman Space Telescope: II. Analysis of the simulated images and implications for weak lensing
Simulating image coaddition with the Nancy Grace Roman Space Telescope: II. Analysis of the simulated images and implications for weak lensing Open
One challenge for applying current weak lensing analysis tools to the Nancy Grace Roman Space Telescope is that individual images will be undersampled. Our companion paper presented an initial application of Imcom - an algorithm that build…
View article: Lyman-α polarization from cosmological ionization fronts: I. Radiative transfer simulations
Lyman-α polarization from cosmological ionization fronts: I. Radiative transfer simulations Open
In this paper, we present the formalism of simulating Lyman-$α$ emission and polarization around reionization ($z$ = 8) from a plane-parallel ionization front. We accomplish this by using a Monte Carlo method to simulate the production of …
View article: Lyman-$α$ polarization from cosmological ionization fronts: II. Implications for intensity mapping
Lyman-$α$ polarization from cosmological ionization fronts: II. Implications for intensity mapping Open
This is the second paper in a series whose aim is to predict the power spectrum of intensity and polarized intensity from cosmic reionization fronts. After building the analytic models for intensity and polarized intensity calculations in …
View article: Probing large-scale ionizing background fluctuation with Lyman α forest and galaxy cross-correlation at <i>z</i> = 2.4
Probing large-scale ionizing background fluctuation with Lyman α forest and galaxy cross-correlation at <i>z</i> = 2.4 Open
The amplitude of the metagalactic ultraviolet background (UVB) at large scales is impacted by two factors. First, it naturally attenuates at scales larger than mean-free path of UVB photons due to the absorption by neutral intergalactic me…
View article: Impact of inhomogeneous reionization on post-reionization 21 cm intensity mapping measurement of cosmological parameters
Impact of inhomogeneous reionization on post-reionization 21 cm intensity mapping measurement of cosmological parameters Open
21 cm intensity mapping (IM) has the potential to be a strong and unique probe of cosmology from redshift of order unity to redshift potentially as high as 30. For post-reionization 21 cm observations, the signal is modulated by the therma…
View article: Weak gravitational lensing shear estimation with <scp>metacalibration</scp> for the <i>Roman</i> High-Latitude Imaging Survey
Weak gravitational lensing shear estimation with <span>metacalibration</span> for the <i>Roman</i> High-Latitude Imaging Survey Open
We investigate the performance of the metacalibration shear calibration framework using simulated imaging data for the Nancy Grace Roman Space Telescope (Roman) reference High-Latitude Imaging Survey (HLIS). The weak lensing programme of R…
View article: Probing Large Scale Ionizing Background Fluctuation with Lyman $α$ Forest and Galaxy Cross-correlation at z=2.4
Probing Large Scale Ionizing Background Fluctuation with Lyman $α$ Forest and Galaxy Cross-correlation at z=2.4 Open
The amplitude of the metagalactic ultraviolet background (UVB) at large-scales is impacted by two factors. First, it naturally attenuates at scales larger than mean-free-path of UVB photons due to the absorption by neutral intergalactic me…
View article: A Synthetic Roman Space Telescope High-Latitude Time-Domain Survey: Supernovae in the Deep Field
A Synthetic Roman Space Telescope High-Latitude Time-Domain Survey: Supernovae in the Deep Field Open
NASA will launch the Nancy Grace Roman Space Telescope (Roman) in the second half of this decade, which will allow for a generation-defining measurement of dark energy through multiple probes, including Type Ia supernovae (SNe Ia). To impr…
View article: Weak Gravitational Lensing Shear Estimation with Metacalibration for the Roman High-Latitude Imaging Survey
Weak Gravitational Lensing Shear Estimation with Metacalibration for the Roman High-Latitude Imaging Survey Open
We investigate the performance of the Metacalibration shear calibration framework using simulated imaging data for the Nancy Grace Roman Space Telescope (Roman) reference High-Latitude Imaging Survey (HLIS). The weak lensing program of the…
View article: Streaming velocity effects on the post-reionization 21-cm baryon acoustic oscillation signal
Streaming velocity effects on the post-reionization 21-cm baryon acoustic oscillation signal Open
The relative velocity between baryons and dark matter in the early Universe can suppress the formation of small-scale baryonic structure and leave an imprint on the baryon acoustic oscillation (BAO) scale at low redshifts after reionizatio…
View article: Streaming Velocity Effects on the Post-reionization 21 cm Baryon Acoustic Oscillation Signal
Streaming Velocity Effects on the Post-reionization 21 cm Baryon Acoustic Oscillation Signal Open
The relative velocity between baryons and dark matter in the early Universe can suppress the formation of small-scale baryonic structure and leave an imprint on the baryon acoustic oscillation (BAO) scale at low redshifts after reionizatio…
View article: A synthetic <i>Roman Space Telescope</i> High-Latitude Imaging Survey: simulation suite and the impact of wavefront errors on weak gravitational lensing
A synthetic <i>Roman Space Telescope</i> High-Latitude Imaging Survey: simulation suite and the impact of wavefront errors on weak gravitational lensing Open
The Nancy Grace Roman Space Telescope (Roman) mission is expected to launch in the mid-2020s. Its weak lensing program is designed to enable unprecedented systematics control in photometric measurements, including shear recovery, point spr…
View article: A Synthetic WFIRST High-Latitude Imaging Survey: Simulation Suite and the Impact of Wavefront Errors on Weak Gravitational Lensing
A Synthetic WFIRST High-Latitude Imaging Survey: Simulation Suite and the Impact of Wavefront Errors on Weak Gravitational Lensing Open
The Wide-Field InfraRed Survey Telescope (WFIRST) mission is expected to launch in the mid-2020s. Its weak lensing program is designed to enable unprecedented systematics control in photometric measurements, including shear recovery, point…