Estimation and compensation of I/Q linear phase imbalance based on the generalized cross correlation and cross-power spectrum phase method

AbstractThe cross power spectrum of the 21 cm signal and Lyman-α emitters (LAEs) is a probe of the Epoch of Reionization. Astrophysical foregrounds do not correlate with the LAE distribution, though the foregrounds contribute to the error. To study the impact of foregrounds on the measurement, we assume realistic observation by the Murchison Widefield Array using a catalogue of radio galaxies, a LAE survey by the Subaru Hyper Supreme-Cam and the redshift of LAEs is determined by the Prime Focus Spectrograph. The HI distribution is estimated from a radiative transfer simulation with models based on results of radiation hydrodynamics simulation. Using these models, we found that the error of cross power spectrum is dominated by foreground terms. Furthermore, we estimate the effects of foreground removal, and find 99% of the foreground removal is required to detect the 21 cm-LAE signal at k ∼ 0.4 h Mpc−1.

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Detectability of 21-cm signal during the epoch of reionization with 21-cm-Lyman-α emitter cross-correlation – III. Model dependence

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa979 ◽

2020 ◽

Vol 494 (3) ◽

pp. 3131-3140 ◽

Cited By ~ 1

Author(s):

Kenji Kubota ◽

Akio K Inoue ◽

Kenji Hasegawa ◽

Keitaro Takahashi

Keyword(s):

Power Spectrum ◽

Luminosity Function ◽

Large Scale ◽

Cross Correlation ◽

Line Emission ◽

Observation Time ◽

Dark Matter Halo ◽

Small Scale ◽

Cross Power Spectrum ◽

The Continuum

ABSTRACT Detecting H i 21-cm line in the intergalactic medium during the epoch of reionization suffers from foreground contamination such as Galactic synchrotron and extragalactic radio sources. Cross-correlation between the 21-cm line and Lyman-α emitter (LAE) galaxies is a powerful tool to identify the 21-cm signal since the 21-cm line emission has correlation with LAEs, while the LAEs are statistically independent of the foregrounds. So far, the detectability of 21-cm-LAE cross-power spectrum has been investigated with simple LAE models where the observed Lyα luminosity is proportional to the dark matter halo mass. However, the previous models were inconsistent with the latest observational data of LAEs obtained with Subaru/Hyper Suprime-Cam (HSC). Here, we revisit the detectability of 21-cm-LAE cross-power spectrum adopting a state-of-the-art LAE model consistent with all Subaru/HSC observations such as the Lyα luminosity function, LAE angular autocorrelation, and the LAE fractions in the continuum selected galaxies. We find that resultant cross-power spectrum with the updated LAE model is reduced at small scales ($k\sim 1\ \rm Mpc^{-1}$) compared to the simple models, while the amplitudes at large scales ($k \lesssim 0.2 \ \rm Mpc^{-1}$) are not affected so much. We conclude that the large-scale signal would be detectable with Square Kilometre Array (SKA) and HSC LAE cross-correlation but detecting the small-scale signal would require an extended HSC LAE survey with an area of $\sim 75\ \rm deg^2$ or 3000 h observation time of 21-cm line with SKA.

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Cross-correlation between cosmological and astrophysical datasets: the Planck and Herschel case

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314013647 ◽

2014 ◽

Vol 10 (S306) ◽

pp. 202-205 ◽

Cited By ~ 2

Author(s):

Federico Bianchini ◽

Andrea Lapi

Keyword(s):

Power Spectrum ◽

Cross Correlation ◽

Forthcoming Paper ◽

Joint Analysis ◽

Atlas Data ◽

Λcdm Model ◽

The Galaxy ◽

The Cross ◽

Galaxy Bias ◽

Cross Power Spectrum

AbstractWe present the first measurement of the correlation between the map of the CMB lensing potential derived from the Planck nominal mission data and z ≳ 1.5 galaxies detected by Herschel-ATLAS (H-ATLAS) survey covering about 550 deg2. We detect the cross-power spectrum with a significance of ∼ 8.5σ, ruling out the absence of correlation at 9σ. We check detection with a number of null tests. The amplitude of cross-correlation and the galaxy bias are estimated using joint analysis of the cross-power spectrum and the galaxy survey auto-spectrum, which allows to break degeneracy between these parameters. The estimated galaxy bias is consistent with previous estimates of the bias for the H-ATLAS data, while the cross-correlation amplitude is higher than expected for a ΛCDM model. The content of this work is to appear in a forthcoming paper Bianchini, et al. (2014).

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The completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: a multitracer analysis in Fourier space for measuring the cosmic structure growth and expansion rate

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab849 ◽

2021 ◽

Vol 504 (1) ◽

pp. 33-52

Author(s):

Gong-Bo Zhao ◽

Yuting Wang ◽

Atsushi Taruya ◽

Weibing Zhang ◽

Héctor Gil-Marín ◽

...

Keyword(s):

Growth Rate ◽

Power Spectrum ◽

Confidence Level ◽

Expansion Rate ◽

Fourier Space ◽

Redshift Range ◽

Significance Level ◽

Data Product ◽

New Development ◽

Cross Power Spectrum

ABSTRACT We perform a joint BAO and RSD analysis using the eBOSS DR16 LRG and ELG samples in the redshift range of z ∈ [0.6, 1.1], and detect an RSD signal from the cross-power spectrum at a ∼4σ confidence level, i.e., fσ8 = 0.317 ± 0.080 at zeff = 0.77. Based on the chained power spectrum, which is a new development in this work to mitigate the angular systematics, we measure the BAO distances and growth rate simultaneously at two effective redshifts, namely, DM/rd (z = 0.70) = 17.96 ± 0.51, DH/rd (z = 0.70) = 21.22 ± 1.20, fσ8 (z = 0.70) = 0.43 ± 0.05, and DM/rd (z = 0.845) = 18.90 ± 0.78, DH/rd (z = 0.845) = 20.91 ± 2.86, fσ8 (z = 0.845) = 0.30 ± 0.08. Combined with BAO measurements including those from the eBOSS DR16 QSO and Lyman-α sample, our measurement has raised the significance level of a non-zero ΩΛ to ∼11σ. The data product of this work is publicly available at https://github.com/icosmology/eBOSS_DR16_LRGxELG and https://www.sdss.org/science/final-bao-and-rsd-measurements/.

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