Browsing by Author "Hoekstra, H."

Now showing 1 - 4 of 4
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    A Measurement of Weak Lensing by Large-Scale Structure in Red-Sequence Cluster Survey Fields
    (2002) Hoekstra, H.; Barrientos, Luis Felipe; Infante Lira, Leopoldo
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    A multi-wavelength mass analysis of RCS2 J232727.6-020437, A similar to 3 x 10(15) M-circle dot galaxy cluster AT z=0.7
    (2015) Sharon, K.; Gladders, M. D.; Marrone, D. P.; Hoekstra, H.; Rasia, E.; Barrientos, Luis Felipe
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    Cluster Cosmology Constraints from the 2500 deg2 SPT-SZ Survey: Inclusion of Weak Gravitational Lensing Data from Magellan and the Hubble Space Telescope
    (2019) Bocquet, S.; Dietrich, J. P.; Schrabback, T.; Bleem, L. E.; Klein, M.; Allen, S. W.; Applegate, D. E.; Ashby, M. L. N.; Bautz, M.; Bayliss, M.; Benson, B. A.; Brodwin, M.; Bulbul, E.; Canning, R. E. A.; Capasso, R.; Carlstrom, J. E.; Chang, C. L.; Chiu, I; Cho, H-M; Clocchiatti, A.; Crawford, T. M.; Crites, A. T.; de Haan, T.; Desai, S.; Dobbs, M. A.; Foley, R. J.; Forman, W. R.; Garmire, G. P.; George, E. M.; Gladders, M. D.; Gonzalez, A. H.; Grandis, S.; Gupta, N.; Halverson, N. W.; Hlavacek-Larrondo, J.; Hoekstra, H.; Holder, G. P.; Holzapfel, W. L.; Hou, Z.; Hrubes, J. D.; Huang, N.; Jones, C.; Khullar, G.; Knox, L.; Kraft, R.; Lee, A. T.; von der Linden, A.; Luong-Van, D.; Mantz, A.; Marrone, D. P.; McDonald, M.; McMahon, J. J.; Meyer, S. S.; Mocanu, L. M.; Mohr, J. J.; Morris, R. G.; Padin, S.; Patil, S.; Pryke, C.; Rapetti, D.; Reichardt, C. L.; Rest, A.; Ruhl, J. E.; Saliwanchik, B. R.; Saro, A.; Sayre, J. T.; Schaffer, K. K.; Shirokoff, E.; Stalder, B.; Stanford, S. A.; Staniszewski, Z.; Stark, A. A.; Story, K. T.; Strazzullo, V; Stubbs, C. W.; Vanderlinde, K.; Vieira, J. D.; Vikhlinin, A.; Williamson, R.; Zenteno, A.
    We derive cosmological constraints using a galaxy cluster sample selected from the 2500 deg(2) SPT-SZ survey. The sample spans the redshift range 0.25 < z < 1.75 and contains 343 clusters with SZ detection significance xi > 5. The sample is supplemented with optical weak gravitational lensing measurements of 32 clusters with 0.29 < z < 1.13 (from Magellan and Hubble Space Telescope) and X-ray measurements of 89 clusters with 0.25 < z < 1.75 (from Chandra). We rely on minimal modeling assumptions: (i) weak lensing provides an accurate means of measuring halo masses, (ii) the mean SZ and X-ray observables are related to the true halo mass through power-law relations in mass and dimensionless Hubble parameter E(z) with a priori unknown parameters, and (iii) there is (correlated, lognormal) intrinsic scatter and measurement noise relating these observables to their mean relations. We simultaneously fit for these astrophysical modeling parameters and for cosmology. Assuming a flat nu Lambda CDM model, in which the sum of neutrino masses is a free parameter, we measure Omega(m) = 0.276 +/- 0.047, sigma(8) = 0.781 +/- 0.037, and sigma(8)(Omega(m)/0.3)(0.2) = 0.766 +/- 0.025. The redshift evolutions of the X-ray Y-X-mass and M-gas-mass relations are both consistent with self-similar evolution to within 1 sigma. The mass slope of the Y-X-mass relation shows a 2.3 sigma deviation from self-similarity. Similarly, the mass slope of the M-gas-mass relation is steeper than self-similarity at the 2.5 sigma level. In a nu omega CDM cosmology, we measure the dark energy equation-of-state parameter w = -1.55 +/- 0.41 from the cluster data. We perform a measurement of the growth of structure since redshift z similar to 1.7 and find no evidence for tension with the prediction from general relativity. This is the first analysis of the SPT cluster sample that uses direct weak-lensing mass calibration and is a step toward using the much larger weak-lensing data set from DES. We provide updated redshift and mass estimates for the SPT sample.
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    Scaling Relations and Overabundance of Massive Clusters at z ≳ 1 from Weak-lensing Studies with the Hubble Space Telescope
    (2011) Jee, M. J.; Dawson, K. S.; Hoekstra, H.; Perlmutter, S.; Rosati, P.; Brodwin, M.; Suzuki, N.; Koester, B.; Postman, M.; Lubin, L.; Meyers, J.; Stanford, S. A.; Barbary, K.; Barrientos, F.; Eisenhardt, P.; Ford, H. C.; Gilbank, D. G.; Gladders, M. D.; Gonzalez, A.; Harris, D. W.; Huang, X.; Lidman, C.; Rykoff, E. S.; Rubin, D.; Spadafora, A. L.
    We present weak gravitational lensing analysis of 22 high-redshift (z greater than or similar to 1) clusters based on Hubble Space Telescope images. Most clusters in our sample provide significant lensing signals and are well detected in their reconstructed two-dimensional mass maps. Combining the current results and our previous weak-lensing studies of five other high-z clusters, we compare gravitational lensing masses of these clusters with other observables. We revisit the question whether the presence of the most massive clusters in our sample is in tension with the current. CDM structure formation paradigm. We find that the lensing masses are tightly correlated with the gas temperatures and establish, for the first time, the lensing mass-temperature relation at z greater than or similar to 1. For the power-law slope of the M-T-X relation (M proportional to T-alpha), we obtain alpha = 1.54 +/- 0.23. This is consistent with the theoretical self-similar prediction alpha = 3/2 and with the results previously reported in the literature for much lower redshift samples. However, our normalization is lower than the previous results by 20%-30%, indicating that the normalization in the M-T-X relation might evolve. After correcting for Eddington bias and updating the discovery area with a more conservative choice, we find that the existence of the most massive clusters in our sample still provides a tension with the current. CDM model. The combined probability of finding the four most massive clusters in this sample after the marginalization over cosmological parameters is less than 1%.