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تسجيل مستخدم جديدMeasurements of E-Mode Polarization and Temperature-E-Mode Correlation in the Cosmic Microwave Background from 100 Square Degrees of SPTpol Data
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We present measurements of $E$-mode polarization and temperature-$E$-mode correlation in the cosmic microwave background (CMB) using data from the first season of observations with SPTpol, the polarization-sensitive receiver currently installed on the South Pole Telescope (SPT). The observations used in this work cover 100~sqdeg of sky with arcminute resolution at $150,$GHz. We report the $E$-mode angular auto-power spectrum ($EE$) and the temperature-$E$-mode angular cross-power spectrum ($TE$) over the multipole range $500 < ell leq5000$. These power spectra improve on previous measurements in the high-$ell$ (small-scale) regime. We fit the combination of the SPTpol power spectra, data from planck, and previous SPT measurements with a six-parameter LCDM cosmological model. We find that the best-fit parameters are consistent with previous results. The improvement in high-$ell$ sensitivity over previous measurements leads to a significant improvement in the limit on polarized point-source power: after masking sources brighter than 50,mJy in unpolarized flux at 150,GHz, we find a 95% confidence upper limit on unclustered point-source power in the $EE$ spectrum of $D_ell = ell (ell+1) C_ell / 2 pi < 0.40 mu{mbox{K}}^2$ at $ell=3000$, indicating that future $EE$ measurements will not be limited by power from unclustered point sources in the multipole range $ell < 3600$, and possibly much higher in $ell.$
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We present a measurement of the $B$-mode polarization power spectrum (the $BB$ spectrum) from 100 $mathrm{deg}^2$ of sky observed with SPTpol, a polarization-sensitive receiver currently installed on the South Pole Telescope. The observations used in
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We report a B-mode power spectrum measurement from the cosmic microwave background (CMB) polarization anisotropy observations made using the SPTpol instrument on the South Pole Telescope. This work uses 500 deg$^2$ of SPTpol data, a five-fold increas
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We present measurements of the $E$-mode polarization angular auto-power spectrum ($EE$) and temperature-$E$-mode cross-power spectrum ($TE$) of the cosmic microwave background (CMB) using 150 GHz data from three seasons of SPTpol observations. We rep
ort the power spectra over the spherical harmonic multipole range $50 < ell leq 8000$, and detect nine acoustic peaks in the $EE$ spectrum with high signal-to-noise ratio. These measurements are the most sensitive to date of the $EE$ and $TE$ power spectra at $ell > 1050$ and $ell > 1475$, respectively. The observations cover 500 deg$^2$, a fivefold increase in area compared to previous SPTpol analyses, which increases our sensitivity to the photon diffusion damping tail of the CMB power spectra enabling tighter constraints on LCDM model extensions. After masking all sources with unpolarized flux $>50$ mJy we place a 95% confidence upper limit on residual polarized point-source power of $D_ell = ell(ell+1)C_ell/2pi <0.107,mu{rm K}^2$ at $ell=3000$, suggesting that the $EE$ damping tail dominates foregrounds to at least $ell = 4050$ with modest source masking. We find that the SPTpol dataset is in mild tension with the $Lambda CDM$ model ($2.1,sigma$), and different data splits prefer parameter values that differ at the $sim 1,sigma$ level. When fitting SPTpol data at $ell < 1000$ we find cosmological parameter constraints consistent with those for $Planck$ temperature. Including SPTpol data at $ell > 1000$ results in a preference for a higher value of the expansion rate ($H_0 = 71.3 pm 2.1,mbox{km},s^{-1}mbox{Mpc}^{-1}$ ) and a lower value for present-day density fluctuations ($sigma_8 = 0.77 pm 0.02$).
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cope. This analysis uses observations of a 1500 deg$^2$ region at 95, 150, and 220 GHz taken over a four month period in 2018. We report binned values of the $EE$ and $TE$ power spectra over the angular multipole range $300 le ell < 3000$, using the multifrequency data to construct six semi-independent estimates of each power spectrum and their minimum-variance combination. These measurements improve upon the previous results of SPTpol across the multipole ranges $300 le ell le 1400$ for $EE$ and $300 le ell le 1700$ for $TE$, resulting in constraints on cosmological parameters comparable to those from other current leading ground-based experiments. We find that the SPT-3G dataset is well-fit by a $Lambda$CDM cosmological model with parameter constraints consistent with those from Planck and SPTpol data. From SPT-3G data alone, we find $H_0 = 68.8 pm 1.5 mathrm{km,s^{-1},Mpc^{-1}}$ and $sigma_8 = 0.789 pm 0.016$, with a gravitational lensing amplitude consistent with the $Lambda$CDM prediction ($A_L = 0.98 pm 0.12$). We combine the SPT-3G and the Planck datasets and obtain joint constraints on the $Lambda$CDM model. The volume of the 68% confidence region in six-dimensional $Lambda$CDM parameter space is reduced by a factor of 1.5 compared to Planck-only constraints, with only slight shifts in central values. We note that the results presented here are obtained from data collected during just half of a typical observing season with only part of the focal plane operable, and that the active detector count has since nearly doubled for observations made with SPT-3G after 2018.
We present a measurement of the cosmic microwave background (CMB) gravitational lensing potential using data from the first two seasons of observations with SPTpol, the polarization-sensitive receiver currently installed on the South Pole Telescope (
SPT). The observations used in this work cover 100 deg$^2$ of sky with arcminute resolution at 150 GHz. Using a quadratic estimator, we make maps of the CMB lensing potential from combinations of CMB temperature and polarization maps. We combine these lensing potential maps to form a minimum-variance (MV) map. The lensing potential is measured with a signal-to-noise ratio of greater than one for angular multipoles between $100< L <250$. This is the highest signal-to-noise mass map made from the CMB to date and will be powerful in cross-correlation with other tracers of large-scale structure. We calculate the power spectrum of the lensing potential for each estimator, and we report the value of the MV power spectrum between $100< L <2000$ as our primary result. We constrain the ratio of the spectrum to a fiducial $Lambda$CDM model to be $A_{rm MV}=0.92 pm 0.14 {rm, (Stat.)} pm 0.08 {rm, (Sys.)}$. Restricting ourselves to polarized data only, we find $A_{rm POL}=0.92 pm 0.24 {rm, (Stat.)} pm 0.11 {rm, (Sys.)}$. This measurement rejects the hypothesis of no lensing at $5.9 sigma$ using polarization data alone, and at $14 sigma$ using both temperature and polarization data.
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