ABSTRACT We present Chandra ACIS-S and Australia Telescope Compact Array (ATCA) radio continuum observations of the strongly lensed dusty, star-forming galaxy SPT-S J034640-5204.9 (hereafter ...SPT0346-52) at z = 5.656. This galaxy has also been observed with ALMA, HST, Spitzer, Herschel, Atacama Pathfinder EXperiment, and the Very Large Telescope. Previous observations indicate that if the infrared (IR) emission is driven by star formation, then the inferred lensing-corrected star formation rate (SFR) (∼4500 M☉ yr−1) and SFR surface density SFR (∼2000 M☉ yr−1 kpc−2) are both exceptionally high. It remained unclear from the previous data, however, whether a central active galactic nucleus (AGN) contributes appreciably to the IR luminosity. The Chandra upper limit shows that SPT0346-52 is consistent with being star formation dominated in the X-ray, and any AGN contribution to the IR emission is negligible. The ATCA radio continuum upper limits are also consistent with the FIR-to-radio correlation for star-forming galaxies with no indication of an additional AGN contribution. The observed prodigious intrinsic IR luminosity of (3.6 0.3) × 1013 L☉ originates almost solely from vigorous star formation activity. With an intrinsic source size of 0.61 0.03 kpc, SPT0346-52 is confirmed to have one of the highest SFR of any known galaxy. This high SFR, which approaches the Eddington limit for a radiation pressure supported starburst, may be explained by a combination of very high star formation efficiency and gas fraction.
Abstract
We report new measurements of millimeter-wave power spectra in the angular multipole range 2000 ≤
ℓ
≤ 11,000 (angular scales
). By adding 95 and 150 GHz data from the low-noise 500 deg
2
...SPTpol survey to the SPT-SZ three-frequency 2540 deg
2
survey, we substantially reduce the uncertainties in these bands. These power spectra include contributions from the primary cosmic microwave background, cosmic infrared background, radio galaxies, and thermal and kinematic Sunyaev–Zel’dovich (SZ) effects. The data favor a thermal SZ (tSZ) power at 143 GHz of
and a kinematic SZ (kSZ) power of
. This is the first measurement of kSZ power at ≥3
σ
. However, different assumptions about the CIB or SZ models can reduce the significance down to 2.4
σ
in the worst case. We study the implications of the measured kSZ power for the epoch of reionization under the Calabrese et al. model for the kSZ power spectrum and find the duration of reionization to be
(
at 95% confidence), when combined with our previously published tSZ bispectrum measurement. The upper limit tightens to
if the assumed homogeneous kSZ power is increased by 25% (∼0.5
μ
K
2
) and relaxes to
if the homogeneous kSZ power is decreased by the same amount.
In the cores of some clusters of galaxies the hot intracluster plasma is dense enough that it should cool radiatively in the cluster's lifetime, leading to continuous 'cooling flows' of gas sinking ...towards the cluster centre, yet no such cooling flow has been observed. The low observed star-formation rates and cool gas masses for these 'cool-core' clusters suggest that much of the cooling must be offset by feedback to prevent the formation of a runaway cooling flow. Here we report X-ray, optical and infrared observations of the galaxy cluster SPT-CLJ2344-4243 (ref. 11) at redshift z = 0.596. These observations reveal an exceptionally luminous (8.2 × 10(45) erg s(-1)) galaxy cluster that hosts an extremely strong cooling flow (around 3,820 solar masses a year). Further, the central galaxy in this cluster appears to be experiencing a massive starburst (formation of around 740 solar masses a year), which suggests that the feedback source responsible for preventing runaway cooling in nearby cool-core clusters may not yet be fully established in SPT-CLJ2344-4243. This large star-formation rate implies that a significant fraction of the stars in the central galaxy of this cluster may form through accretion of the intracluster medium, rather than (as is currently thought) assembling entirely via mergers.
We present component-separated maps of the primary cosmic microwave background/kinematic Sunyaev–Zel’dovich (SZ) amplitude and the thermal SZ Compton-y parameter, created using data from the South ...Pole Telescope (SPT) and the Planck satellite. These maps, which cover the ∼2500 deg2 of the southern sky imaged by the SPT-SZ survey, represent a significant improvement over previous such products available in this region by virtue of their higher angular resolution (1.′25 for our highest-resolution Compton-y maps) and lower noise at small angular scales. In this work we detail the construction of these maps using linear combination techniques, including our method for limiting the correlation of our lowest-noise Compton-y map products with the cosmic infrared background. We perform a range of validation tests on these data products to test our sky modeling and combination algorithms, and we find good performance in all of these tests. Recognizing the potential utility of these data products for a wide range of astrophysical and cosmological analyses, including studies of the gas properties of galaxies, groups, and clusters, we make these products publicly available at http://pole.uchicago.edu/public/data/sptsz_ymap and on the NASA/LAMBDA website.
COSMOLOGY WITH THE SUNYAEV-ZEL'DOVICH EFFECT Carlstrom, John E; Holder, Gilbert P; Reese, Erik D
Annual review of astronomy and astrophysics,
01/2002, Volume:
40, Issue:
1
Journal Article
Peer reviewed
The Sunyaev-Zel'dovich effect (SZE) provides a unique way to map the
large-scale structure of the universe as traced by massive clusters of
galaxies. As a spectral distortion of the cosmic microwave ...background, the SZE
is insensitive to the redshift of the galaxy cluster, making it well-suited for
studies of clusters at all redshifts, and especially at reasonably high
redshifts (
z
> 1) where the abundance of clusters is critically
dependent on the underlying cosmology. Recent high signal-to-noise detections
of the SZE have enabled interesting constraints on the Hubble constant and on
the matter density of the universe using small samples of galaxy clusters.
Upcoming SZE surveys are expected to find hundreds to thousands of new galaxy
clusters, with a mass selection function that is remarkably uniform with
redshift. In this review we provide an overview of the SZE and its use for
cosmological studies, with emphasis on the cosmology that can, in principle, be
extracted from SZE survey yields. We discuss the observational and theoretical
challenges that must be met before precise cosmological constraints can be
extracted from the survey yields.
Here, we present constraints on extensions to the Λ CDM cosmological model from measurements of the E-mode polarization autopower spectrum and the temperature-E-mode cross-power spectrum of the ...cosmic microwave background (CMB) made using 2018 SPT-3G data. The extensions considered vary the primordial helium abundance, the effective number of relativistic degrees of freedom, the sum of neutrino masses, the relativistic energy density and mass of a sterile neutrino, and the mean spatial curvature. We do not find clear evidence for any of these extensions, from either the SPT-3G 2018 dataset alone or in combination with baryon acoustic oscillation and Planck data. None of these model extensions significantly relax the tension between Hubble-constant, H0, constraints from the CMB and from distance-ladder measurements using Cepheids and supernovae. The addition of the SPT-3G 2018 data to Planck reduces the square-root of the determinants of the parameter covariance matrices by factors of 1.3–2.0 across these models, signaling a substantial reduction in the allowed parameter volume. We also explore CMB-based constraints on H0 from combined SPT, Planck, and ACT DR4 datasets. While individual experiments see some indications of different H0 values between the TT, TE, and EE spectra, the combined H0 constraints are consistent between the three spectra. For the full combined datasets, we report H0 = 67.49 ± 0.53 km s-1 Mpc -1, which is the tightest constraint on H0 from CMB power spectra to date and in 4.1σ tension with the most precise distance-ladder-based measurement of H0. The SPT-3G survey is planned to continue through at least 2023, with existing maps of combined 2019 and 2020 data already having ~ 3.5 x lower noise than the maps used in this analysis.
We cross-match galaxy cluster candidates selected via their Sunyaev–Zel'dovich effect (SZE) signatures in 129.1 deg2 of the South Pole Telescope 2500d SPT-SZ survey with optically identified clusters ...selected from the Dark Energy Survey science verification data. We identify 25 clusters between 0.1 ≲ z ≲ 0.8 in the union of the SPT-SZ and redMaPPer (RM) samples. RM is an optical cluster finding algorithm that also returns a richness estimate for each cluster. We model the richness λ-mass relation with the following function 〈ln λ|M
500〉 ∝ B
λln M
500 + C
λln E(z) and use SPT-SZ cluster masses and RM richnesses λ to constrain the parameters. We find
$B_\lambda = 1.14^{+0.21}_{-0.18}$
and
$C_\lambda =0.73^{+0.77}_{-0.75}$
. The associated scatter in mass at fixed richness is
$\sigma _{\ln M|\lambda } = 0.18^{+0.08}_{-0.05}$
at a characteristic richness λ = 70. We demonstrate that our model provides an adequate description of the matched sample, showing that the fraction of SPT-SZ-selected clusters with RM counterparts is consistent with expectations and that the fraction of RM-selected clusters with SPT-SZ counterparts is in mild tension with expectation. We model the optical-SZE cluster positional offset distribution with the sum of two Gaussians, showing that it is consistent with a dominant, centrally peaked population and a subdominant population characterized by larger offsets. We also cross-match the RM catalogue with SPT-SZ candidates below the official catalogue threshold significance ξ = 4.5, using the RM catalogue to provide optical confirmation and redshifts for 15 additional clusters with ξ ∈ 4, 4.5.
ABSTRACT We present measurements of E-mode polarization and temperature-E-mode correlation in the cosmic microwave background 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 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 < ≤ 5000. These power spectra improve on previous measurements in the high- (small-scale) regime. We fit the combination of the SPTpol power spectra, data from Planck, and previous SPT measurements with a six-parameter ΛCDM cosmological model. We find that the best-fit parameters are consistent with previous results. The improvement in high- 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 at , indicating that future EE measurements will not be limited by power from unclustered point sources in the multipole range , and possibly much higher in
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