Topic
Sunyaev–Zel'dovich Array
About: Sunyaev–Zel'dovich Array is a research topic. Over the lifetime, 14 publications have been published within this topic receiving 390 citations.
Papers
TL;DR: In this article, the Sunyaev-Zel'dovich (SZ) effect was measured in three high-redshift (0.89 < z < 1.03) X-ray selected galaxy clusters.
Abstract: We report measurements of the Sunyaev-Zel'dovich (SZ) effect in three high-redshift (0.89 < z < 1.03), X-ray selected galaxy clusters. The observations were obtained at 30 GHz during the commissioning period of a new, eight-element interferometer -- the Sunyaev-Zel'dovich Array (SZA) -- built for dedicated SZ effect observations. The SZA observations are sensitive to angular scales larger than those subtended by the virial radii of the clusters. Assuming isothermality and hydrostatic equilibrium for the intracluster medium, and gas-mass fractions consistent with those for clusters at moderate redshift, we calculate electron temperatures, gas masses, and total cluster masses from the SZ data. The SZ-derived masses, integrated approximately to the virial radii, are 1.9 ^{+0.5}_{-0.4}x10^{14} solar masses for CLl1415.1+3612, 3.4^{+0.6}_{-0.5}x10^{14} solar masses for CL1429.0+4241, and 7.2^{+1.3}_{-0.9}x10^{14} solar masses for CL1226.9+3332. The SZ-derived quantities are in good agreement with the cluster properties derived from X-ray measurements.
95 citations
TL;DR: In this article, the angular power spectrum of the cosmic microwave background (CMB) obtained with the Sunyaev-Zel'dovich Array was measured for a broad bin centered at multipole 4066 and an upper bound of 155 uK^2 (95% CL) on the secondary contribution to the anisotropy in their maps was established.
Abstract: We present 30 GHz measurements of the angular power spectrum of the cosmic microwave background (CMB) obtained with the Sunyaev-Zel'dovich Array. The measurements are sensitive to arcminute angular scales, where secondary anisotropy from the Sunyaev-Zel'dovich effect (SZE) is expected to dominate. For a broad bin centered at multipole 4066 we find 67+77-50 uK^2, of which 26+/-5 uK^2 is the expected contribution from primary CMB anisotropy and 80+/-54 uK^2 is the expected contribution from undetected radio sources. These results imply an upper limit of 155 uK^2 (95% CL) on the secondary contribution to the anisotropy in our maps. This level of SZE anisotropy power is consistent with expectations based on recent determinations of the normalization of the matter power spectrum, i.e., sigma_8~0.8.
39 citations
University of Pennsylvania1, Rutgers University2, University of Nottingham3, University of Toronto4, Pontifical Catholic University of Chile5, Princeton University6, University of California, Berkeley7, National Institute of Standards and Technology8, University of British Columbia9, University of Miami10, University of Pittsburgh11, Academia Sinica12, Institute for the Physics and Mathematics of the Universe13, Johns Hopkins University14, University of KwaZulu-Natal15, Haverford College16, Stanford University17, West Chester University of Pennsylvania18, Carnegie Mellon University19, Goddard Space Flight Center20
TL;DR: In this article, the Sunyaev-Zel'dovich effect (SZE) was used to detect galaxy clusters in the Atacama Cosmology Telescope (ACT) data.
Abstract: We present follow-up observations with the Sunyaev-Zel'dovich Array (SZA) of optically-confirmed galaxy clusters found in the equatorial survey region of the Atacama Cosmology Telescope (ACT): ACT-CL J0022-0036, ACT-CL J2051+0057, and ACT-CL J2337+0016. ACT-CL J0022-0036 is a newly-discovered, massive (10^15 Msun), high-redshift (z=0.81) cluster revealed by ACT through the Sunyaev-Zel'dovich effect (SZE). Deep, targeted observations with the SZA allow us to probe a broader range of cluster spatial scales, better disentangle cluster decrements from radio point source emission, and derive more robust integrated SZE flux and mass estimates than we can with ACT data alone. For the two clusters we detect with the SZA we compute integrated SZE signal and derive masses from the SZA data only. ACT-CL J2337+0016, also known as Abell 2631, has archival Chandra data that allow an additional X-ray-based mass estimate. Optical richness is also used to estimate cluster masses and shows good agreement with the SZE and X-ray-based estimates. Based on the point sources detected by the SZA in these three cluster fields and an extrapolation to ACT's frequency, we estimate that point sources could be contaminating the SZE decrement at the <= 20% level for some fraction of clusters.
26 citations
University of Chicago1, University of Alabama in Huntsville2, Marshall Space Flight Center3, California Institute of Technology4, Columbia University5, University of Pennsylvania6, Brera Astronomical Observatory7, University of Bristol8, Lawrence Livermore National Laboratory9, University of California, Davis10
TL;DR: In this article, gas constraints from Sunyaev-Zel'dovich (SZ) effect measurements in a sample of eleven X-ray and infrared (IR) selected galaxy clusters at z >= 1, using data from the SZA.
Abstract: We present gas constraints from Sunyaev-Zel'dovich (SZ) effect measurements in a sample of eleven X-ray and infrared (IR) selected galaxy clusters at z >=1, using data from the Sunyaev-Zel'dovich Array (SZA). The cylindrically integrated Compton-y parameter, Y , is calculated by fitting the data to a two-parameter gas pressure profile. Where possible, we also determine the temperature of the hot intra-cluster plasma from Chandra and XMM-Newton data, and constrain the gas mass within the same aperture (r_2500 ) as Y . The SZ effect is detected in the clusters for which the X-ray data indicate gas masses above ~ 10^13 Msun, including XMMU J2235-2557 at redshift z = 1.39, which to date is one of the most distant clusters detected using the SZ effect. None of the IR-selected targets are detected by the SZA measurements, indicating low gas masses for these objects. For these and the four other undetected clusters, we quote upper limits on Y and Mgas_SZ , with the latter derived from scaling relations calibrated with lower redshift clusters. We compare the constraints on Y and X-ray derived gas mass Mgas_X-ray to self-similar scaling relations between these observables determined from observations of lower redshift clusters, finding consistency given the measurement error.
22 citations
TL;DR: In this article, the authors presented the first sample of 31 GHz selected sources to flux levels of 1 mJy, which is significantly higher than predictions based on 1.4-GHz selected samples, a discrepancy which can be explained by a small shift in the spectral index distribution for faint 1.5 GHz sources.
Abstract: We present the first sample of 31-GHz selected sources to flux levels of 1 mJy. From late 2005 to mid 2007, the Sunyaev-Zel'dovich Array (SZA) observed 7.7 square degrees of the sky at 31 GHz to a median rms of 0.18 mJy/beam. We identify 209 sources at greater than 5 sigma significance in the 31 GHz maps, ranging in flux from 0.7 mJy to ~200 mJy. Archival NVSS data at 1.4 GHz and observations at 5 GHz with the Very Large Array are used to characterize the sources. We determine the maximum-likelihood integrated source count to be N(>S) = (27.2 +- 2.5) deg^-2 x (S_mJy)^(-1.18 +- 0.12) over the flux range 0.7 - 15 mJy. This result is significantly higher than predictions based on 1.4-GHz selected samples, a discrepancy which can be explained by a small shift in the spectral index distribution for faint 1.4-GHz sources. From comparison with previous measurements of sources within the central arcminute of massive clusters, we derive an overdensity of 6.8 +- 4.4, relative to field sources.
19 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2012 | 1 |
| 2011 | 3 |
| 2010 | 5 |
| 2009 | 3 |
| 2007 | 1 |
| 2006 | 1 |