146 results on '"GEORGE, E. M."'
Search Results
2. Mapping gas around massive galaxies: cross-correlation of DES Y3 galaxies and Compton-$y$-maps from SPT and Planck
- Author
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Sánchez, J., Omori, Y., Chang, C., Bleem, L. E., Crawford, T., Drlica-Wagner, A., Raghunathan, S., Zacharegkas, G., Abbott, T. M. C., Aguena, M., Alarcon, A., Allam, S., Alves, O., Amon, A., Avila, S., Baxter, E., Bechtol, K., Benson, B. A., Bernstein, G. M., Bertin, E., Bocquet, S., Brooks, D., Burke, D. L., Campos, A., Carlstrom, J. E., Rosell, A. Carnero, Kind, M. Carrasco, Carretero, J., Castander, F. J., Cawthon, R., Chang, C. L., Chen, A., Choi, A., Chown, R., Costanzi, M., Crites, A. T., Crocce, M., da Costa, L. N., Pereira, M. E. S., de Haan, T., De Vicente, J., DeRose, J., Desai, S., Diehl, H. T., Dobbs, M. A., Dodelson, S., Doel, P., Elvin-Poole, J., Everett, W., Everett, S., Ferrero, I., Flaugher, B., Fosalba, P., Frieman, J., García-Bellido, J., Gatti, M., George, E. M., Gerdes, D. W., Giannini, G., Gruen, D., Gruendl, R. A., Gschwend, J., Gutierrez, G., Halverson, N. W., Hinton, S. R., Holder, G. P., Hollowood, D. L., Holzapfel, W. L., Honscheid, K., Hrubes, J. D., James, D. J., Knox, L., Kuehn, K., Kuropatkin, N., Lahav, O., Lee, A. T., Luong-Van, D., MacCrann, N., Marshall, J. L., McCullough, J., McMahon, J. J., Melchior, P., Mena-Fernández, J., Menanteau, F., Miquel, R., Mocanu, L., Mohr, J. J., Muir, J., Myles, J., Natoli, T., Padin, S., Palmese, A., Pandey, S., Paz-Chinchón, F., Pieres, A., Malagón, A. A. Plazas, Porredon, A., Pryke, C., Raveri, M., Reichardt, C. L., Rodriguez-Monroy, M., Ross, A. J., Ruhl, J. E., Rykoff, E., Sánchez, C., Sanchez, E., Scarpine, V., Schaffer, K. K., Sevilla-Noarbe, I., Sheldon, E., Shirokoff, E., Smith, M., Soares-Santos, M., Staniszewski, Z., Stark, A. A., Suchyta, E., Swanson, M. E. C., Tarle, G., Thomas, D., Troxel, M. A., Tucker, D. L., Vieira, J. D., Vincenzi, M., Weaverdyck, N., Williamson, R., Yanny, B., Yin, B., Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), CEA/DSM Centre de Saclay (CEA/DSM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), DES, and SPT
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Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,cosmology: observations ,FOS: Physical sciences ,galaxies: structure ,large-scale structure of Universe ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We cross-correlate positions of galaxies measured in data from the first three years of the Dark Energy Survey with Compton-$y$-maps generated using data from the South Pole Telescope (SPT) and the {\it Planck} mission. We model this cross-correlation measurement together with the galaxy auto-correlation to constrain the distribution of gas in the Universe. We measure the hydrostatic mass bias or, equivalently, the mean halo bias-weighted electron pressure $\langle b_{h}P_{e}\rangle$, using large-scale information. We find $\langle b_{h}P_{e}\rangle$ to be $[0.16^{+0.03}_{-0.04},0.28^{+0.04}_{-0.05},0.45^{+0.06}_{-0.10},0.54^{+0.08}_{-0.07},0.61^{+0.08}_{-0.06},0.63^{+0.07}_{-0.08}]$ meV cm$^{-3}$ at redshifts $z \sim [0.30, 0.46, 0.62,0.77, 0.89, 0.97]$. These values are consistent with previous work where measurements exist in the redshift range. We also constrain the mean gas profile using small-scale information, enabled by the high-resolution of the SPT data. We compare our measurements to different parametrized profiles based on the cosmo-OWLS hydrodynamical simulations. We find that our data are consistent with the simulation that assumes an AGN heating temperature of $10^{8.5}$K but are incompatible with the model that assumes an AGN heating temperature of $10^{8.0}$K. These comparisons indicate that the data prefer a higher value of electron pressure than the simulations within $r_{500c}$ of the galaxies' halos., Comment: 20 pages, 9 figures. Submitted to MNRAS
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- 2023
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3. CMB/kSZ and Compton-y Maps from 2500 deg² of SPT-SZ and Planck Survey Data
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Bleem, L. E., Crawford, T. M., Ansarinejad, B., Benson, B. A., Bocquet, S., Carlstrom, J. E., Chang, C. L., Chown, R., Crites, A. T., de Haan, T., Dobbs, M. A., Everett, W. B., George, E. M., Gualtieri, R., Halverson, N. W., Holder, G. P., Holzapfel, W. L., Hrubes, J. D., Knox, L., Lee, A. T., Luong-Van, D., Marrone, D. P., McMahon, J. J., Meyer, S. S., Millea, M., Mocanu, L. M., Mohr, J. J., Natoli, T., Omori, Y., Padin, S., Pryke, C., Raghunathan, S., Reichardt, C. L., Ruhl, J. E., Schaffer, K. K., Shirokoff, E., Staniszewski, Z., Stark, A. A., Vieira, J. D., and Williamson, R.
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Astrophysics::Instrumentation and Methods for Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics - Abstract
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.
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- 2022
4. A Study of Al–Mn Transition Edge Sensor Engineering for Stability
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George, E. M., Austermann, J. E., Beall, J. A., Becker, D., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H.-M., Crites, A. T., Dobbs, M. A., Everett, W., Halverson, N. W., Henning, J. W., Hilton, G. C., Holzapfel, W. L., Hubmayr, J., Irwin, K. D., Li, D., Lueker, M., McMahon, J. J., Mehl, J., Montgomery, J., Natoli, T., Nibarger, J. P., Niemack, M. D., Novosad, V., Ruhl, J. E., Sayre, J. T., Shirokoff, E., Story, K. T., Wang, G., Yefremenko, V., Yoon, K. W., and Young, E.
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- 2014
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5. Measurement and validation of frailty as a predictor of outcomes in women undergoing major gynaecological surgery
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George, E M, Burke, W M, Hou, J Y, Tergas, A I, Chen, L, Neugut, A I, Ananth, C V, Hershman, D L, and Wright, J D
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- 2016
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6. CMB/kSZ and Compton-$y$ Maps from 2500 square degrees of SPT-SZ and Planck Survey Data
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Bleem, L. E., Crawford, T. M., Ansarinejad, B., Benson, B. A., Bocquet, S., Carlstrom, J. E., Chang, C. L., Chown, R., Crites, A. T., de Haan, T., Dobbs, M. A., Everett, W. B., George, E. M., Gualtieri, R., Halverson, N. W., Holder, G. P., Holzapfel, W. L., Hrubes, J. D., Knox, L., Lee, A. T., Luong-Van, D., Marrone, D. P., McMahon, J. J., Meyer, S. S., Millea, M., Mocanu, L. M., Mohr, J. J., Natoli, T., Omori, Y., Padin, S., Pryke, C., Raghunathan, S., Reichardt, C. L., Ruhl, J. E., Schaffer, K. K., Shirokoff, E., Staniszewski, Z., Stark, A. A., Vieira, J. D., and Williamson, R.
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Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics::Instrumentation and Methods for Astrophysics ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
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 $\sim$2500 square degrees of the Southern sky imaged by the SPT-SZ survey, represent a significant improvement over previous such products available in this region by virtue of their higher angular resolution (1.25 arcminutes for our highest resolution Compton-$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., Minor changes to match version accepted in ApJS
- Published
- 2021
7. An All Silicon Feedhorn-Coupled Focal Plane for Cosmic Microwave Background Polarimetry
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Hubmayr, J., Appel, J. W., Austermann, J. E., Beall, J. A., Becker, D., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H. M., Crites, A. T., Essinger-Hileman, T., Fox, A., George, E. M., Halverson, N. W., Harrington, N. L., Henning, J. W., Hilton, G. C., Holzapfel, W. L., Irwin, K. D., Lee, A. T., Li, D., McMahon, J., Mehl, J., Natoli, T., Niemack, M. D., Newburgh, L. B., Nibarger, J. P., Parker, L. P., Schmitt, B. L., Staggs, S. T., Van Lanen, J., Wollack, E. J., and Yoon, K. W.
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- 2012
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8. Shocks in the stacked Sunyaev-Zel'dovich profiles of clusters II: Measurements from SPT-SZ + Planck Compton-y map.
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(தயா), D Anbajagane, Chang, C, Jain, B, Adhikari, S, Baxter, E J, Benson, B A, Bleem, L E, Bocquet, S, Calzadilla, M S, Carlstrom, J E, Chang, C L, Chown, R, Crawford, T M, Crites, A T, Cui, W, de Haan, T, Mascolo, L Di, Dobbs, M A, Everett, W B, and George, E M
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GALAXY clusters ,LARGE scale structure (Astronomy) ,CLUSTER sampling ,POLARISCOPE ,REDSHIFT ,PHYSICAL cosmology ,GALACTIC redshift - Abstract
We search for the signature of cosmological shocks in stacked gas pressure profiles of galaxy clusters using data from the South Pole Telescope (SPT). Specifically, we stack the latest Compton- y maps from the 2500 deg
2 SPT-SZ survey on the locations of clusters identified in that same data set. The sample contains 516 clusters with mean mass |$\langle M_{\rm 200m}\rangle = 10^{14.9} \, {\rm M}_\odot$| and redshift 〈 z 〉 = 0.55. We analyse in parallel a set of zoom-in hydrodynamical simulations from the three hundred project. The SPT-SZ data show two features: (i) a pressure deficit at R / R200m = 1.08 ± 0.09, measured at 3.1σ significance and not observed in the simulations, and; (ii) a sharp decrease in pressure at R / R200m = 4.58 ± 1.24 at 2.0σ significance. The pressure deficit is qualitatively consistent with a shock-induced thermal non-equilibrium between electrons and ions, and the second feature is consistent with accretion shocks seen in previous studies. We split the cluster sample by redshift and mass, and find both features exist in all cases. There are also no significant differences in features along and across the cluster major axis, whose orientation roughly points towards filamentary structure. As a consistency test, we also analyse clusters from the Planck and Atacama Cosmology Telescope Polarimeter surveys and find quantitatively similar features in the pressure profiles. Finally, we compare the accretion shock radius (|$R_{\rm sh,\, acc}$|) with existing measurements of the splashback radius (Rsp ) for SPT-SZ and constrain the lower limit of the ratio, |$R_{\rm sh,\, acc}/R_{\rm sp}\gt 2.16 \pm 0.59$|. [ABSTRACT FROM AUTHOR]- Published
- 2022
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9. Combining Planck and SPT Cluster Catalogs: Cosmological Analysis and Impact on the Planck Scaling Relation Calibration.
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Salvati, L., Saro, A., Bocquet, S., Costanzi, M., Ansarinejad, B., Benson, B. A., Bleem, L. E., Calzadilla, M. S., Carlstrom, J. E., Chang, C. L., Chown, R., Crites, A. T., Haan, T. de, Dobbs, M. A., Everett, W. B., Floyd, B., Grandis, S., George, E. M., Halverson, N. W., and Holder, G. P.
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PLANCK scale ,COSMIC background radiation ,LARGE scale structure (Astronomy) ,CATALOGS ,CALIBRATION ,CATALOGING - Abstract
We provide the first combined cosmological analysis of the South Pole Telescope (SPT) and Planck cluster catalogs. The aim is to provide an independent calibration for Planck scaling relations, exploiting the cosmological constraining power of the SPT-SZ cluster catalog and its dedicated weak lensing (WL) and X-ray follow-up observations. We build a new version of the Planck cluster likelihood. In the ν Λ CDM scenario, focusing on the mass slope and mass bias of Planck scaling relations, we find α SZ = 1.49 â' 0.10 + 0.07 and 1 â' b SZ = 0.69 â' 0.14 + 0.07 , respectively. The results for the mass slope show a âĽ4 Ď departure from the self-similar evolution, α
SZ ⼠1.8. This shift is mainly driven by the matter density value preferred by SPT data, Ωm = 0.30 ± 0.03, lower than the one obtained by Planck data alone, Ω m = 0.37 â' 0.06 + 0.02 . The mass bias constraints are consistent both with outcomes of hydrodynamical simulations and external WL calibrations, (1 â' b) ⼠0.8, and with results required by the Planck cosmic microwave background cosmology, (1 â' b) ⼠0.6. From this analysis, we obtain a new catalog of Planck cluster masses M500 . We estimate the ratio between the published Planck MSZ masses and our derived masses M500 , as a “measured mass bias,” 1 â' b M . We analyze the mass, redshift, and detection noise dependence of 1 â' b M , finding an increasing trend toward high redshift and low mass. These results mimic the effect of departure from self-similarity in cluster evolution, showing different dependencies for the low-mass, high-mass, low- z, and high- z regimes. [ABSTRACT FROM AUTHOR]- Published
- 2022
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10. Pathophysiology of hypertension in pre-eclampsia: a lesson in integrative physiology
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Palei, A. C., Spradley, F. T., Warrington, J. P., George, E. M., and Granger, J. P.
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- 2013
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11. Dusty starburst galaxies in the early Universe as revealed by gravitational lensing
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Vieira, J. D., Marrone, D. P., Chapman, S. C., De Breuck, C., Hezaveh, Y. D., Wei, A., Aguirre, J. E., Aird, K. A., Aravena, M., Ashby, M. L. N., Bayliss, M., Benson, B. A., Biggs, A. D., Bleem, L. E., Bock, J. J., Bothwell, M., Bradford, C. M., Brodwin, M., Carlstrom, J. E., Chang, C. L., Crawford, T. M., Crites, A. T., de Haan, T., Dobbs, M. A., Fomalont, E. B., Fassnacht, C. D., George, E. M., Gladders, M. D., Gonzalez, A. H., Greve, T. R., Gullberg, B., Halverson, N. W., High, F. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hrubes, J. D., Hunter, T. R., Keisler, R., Lee, A. T., Leitch, E. M., Lueker, M., Luong-Van, D., Malkan, M., McIntyre, V., McMahon, J. J., Mehl, J., Menten, K. M., Meyer, S. S., Mocanu, L. M., Murphy, E. J., Natoli, T., Padin, S., Plagge, T., Reichardt, C. L., Rest, A., Ruel, J., Ruhl, J. E., Sharon, K., Schaffer, K. K., Shaw, L., Shirokoff, E., Spilker, J. S., Stalder, B., Staniszewski, Z., Stark, A. A., Story, K., Vanderlinde, K., Welikala, N., and Williamson, R.
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- 2013
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12. A massive, cooling-flow-induced starburst in the core of a luminous cluster of galaxies
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McDonald, M., Bayliss, M., Benson, B. A., Foley, R. J., Ruel, J., Sullivan, P., Veilleux, S., Aird, K. A., Ashby, M. L. N., Bautz, M., Bazin, G., Bleem, L. E., Brodwin, M., Carlstrom, J. E., Chang, C. L., Cho, H. M., Clocchiatti, A., Crawford, T. M., Crites, A. T., de Haan, T., Desai, S., Dobbs, M. A., Dudley, J. P., Egami, E., Forman, W. R., Garmire, G. P., George, E. M., Gladders, M. D., Gonzalez, A. H., Halverson, N. W., Harrington, N. L., High, F. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hrubes, J. D., Jones, C., Joy, M., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Liu, J., Lueker, M., Luong-Van, D., Mantz, A., Marrone, D. P., McMahon, J. J., Mehl, J., Meyer, S. S., Miller, E. D., Mocanu, L., Mohr, J. J., Montroy, T. E., Murray, S. S., Natoli, T., Padin, S., Plagge, T., Pryke, C., Rawle, T. D., Reichardt, C. L., Rest, A., Rex, M., Ruhl, J. E., Saliwanchik, B. R., Saro, A., Sayre, J. T., Schaffer, K. K., Shaw, L., Shirokoff, E., Simcoe, R., Song, J., Spieler, H. G., Stalder, B., Staniszewski, Z., Stark, A. A., Story, K., Stubbs, C. W., Šuhada, R., van Engelen, A., Vanderlinde, K., Vieira, J. D., Vikhlinin, A., Williamson, R., Zahn, O., and Zenteno, A.
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- 2012
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13. An All Silicon Feedhorn-Coupled Focal Plane for Cosmic Microwave Background Polarimetry
- Author
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Hubmayr, J, Appel, J. W, Austermann, J. E, Beall, J. A, Becker, D, Benson, B. A, Bleem, L. E, Carlstrom, J. E, Chang, C. L, Cho, H. M, Crites, A. T, Essinger-Hileman, T, Fox, A, George, E. M, Halverson, N. W, Harrington, N. L, Henning, J. W, Hilton, G. C, Irwin, K. D, Li, D, Niemack, M. D, Nibarger, J. P, VanLanen, J, Newburgh, L. B, and Parker, L. P
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Astronomy - Abstract
Upcoming experiments aim to produce high fidelity polarization maps of the cosmic microwave background. To achieve the required sensitivity, we are developing monolithic, feedhorn-coupled transition edge sensor polarimeter arrays operating at 150 GHz. We describe this focal plane architecture and the current status of this technology, focusing on single-pixel polarimeters being deployed on the Atacama B-mode Search (ABS) and an 84-pixel demonstration feedhorn array backed by four 10-pixel polarimeter arrays. The feedhorn array exhibits symmetric beams, cross-polar response less than -23 dB and excellent uniformity across the array. Monolithic polarimeter arrays, including arrays of silicon feedhorns, will be used in the Atacama Cosmology Telescope Polarimeter (ACTPol) and the South Pole Telescope Polarimeter (SPTpol) and have been proposed for upcoming balloon-borne instruments.
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- 2011
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14. Testosterone, signal coloration, and signal color perception in male zebra finch contests.
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Green, P. A., George, E. M., Rosvall, K. A., Johnsen, S., and Nowicki, S.
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COLOR vision , *ZEBRA finch , *GONADOTROPIN releasing hormone , *CONTESTS , *TESTOSTERONE , *RED , *ANIMAL coloration - Abstract
Many animals use assessment signals to resolve contests over limited resources while minimizing the costs of those contests. The carotenoid‐based orange to red bills of male zebra finches (Taeniopygia guttata) are thought to function as assessment signals in male–male contests, but behavioral analyses relating contest behaviors and outcomes to bill coloration have yielded mixed results. We examined the relationship between bill color and contests while incorporating measurements of color perception and testosterone (T) production, for an integrative view of aggressive signal behavior, production, and perception. We assayed the T production capabilities of 12 males in response to a gonadotropin‐releasing hormone (GnRH) challenge. We then quantified the initiation, escalation, and outcome of over 400 contests in the group, and measured bill color using calibrated photography. Finally, because signal perception can influence signal function, we tested how males perceive variation in bill coloration, asking if males exhibit categorical perception of bill color, as has been shown recently in female zebra finches. The data suggest that males with greater T production capabilities than their rivals were more likely to initiate contests against those rivals, while males with redder bills than their rivals were more likely to win contests. Males exhibited categorical color perception, but individual variation in the effect of categorical perception on color discrimination abilities did not predict any aspects of contest behavior or outcomes. Our results are consistent with the hypotheses that T plays a role in zebra finch contests and that bill coloration functions as an aggressive signal. We suggest future approaches, based on animal contest theory, for how links among signals, perception, and assessment can be tested. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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15. Fractional Polarisation of Extragalactic Sources in the 500-square-degree SPTpol Survey
- Author
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Gupta, N., Reichardt, C. L., Ade, P. A. R., Anderson, A. J., Archipley, M., Austermann, J. E., Avva, J. S., Beall, J. A., Bender, A. N., Benson, B. A., Bianchini, F., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Chiang, H. C., Citron, R., Moran, C. Corbett, Crawford, T. M., Crites, A. T., de Haan, T., Dobbs, M. A., Everett, W., Feng, C., Gallicchio, J., George, E. M., Gilbert, A., Halverson, N. W., Harrington, N., Henning, J. W., Hilton, G. C., Holder, G. P., Holzapfel, W. L., Hou, Z., Hrubes, J. D., Huang, N., Hubmayr, J., Irwin, K. D., Knox, L., Lee, A. T., Li, D., Lowitz, A., Luong-Van, D., Marrone, D. P., Manzotti, A., McMahon, J. J., Meyer, S. S., Millea, M., Mocanu, L. M., Mohr, J. J., Montgomery, J., Nadolski, A., Natoli, T., Nibarger, J. P., Noble, G. I., Novosad, V., Omori, Y., Padin, S., Patil, S., Pryke, C., Ruhl, J. E., Saliwanchik, B. R., Sayre, J. T., Schaffer, K. K., Shirokoff, E., Sievers, C., Smecher, G., Staniszewski, Z., Stark, A. A., Story, K. T., Switzer, E. R., Tucker, C., Vanderlinde, K., Veach, T., Vieira, J. D., Wang, G., Whitehorn, N., Williamson, R., Wu, W. L. K., Yefremenko, V., and Zhang, L.
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Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,FOS: Physical sciences ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We study the polarisation properties of extragalactic sources at 95 and 150 GHz in the SPTpol 500 deg$^2$ survey. We estimate the polarised power by stacking maps at known source positions, and correct for noise bias by subtracting the mean polarised power at random positions in the maps. We show that the method is unbiased using a set of simulated maps with similar noise properties to the real SPTpol maps. We find a flux-weighted mean-squared polarisation fraction $\langle p^2 \rangle= [8.9\pm1.1] \times 10^{-4}$ at 95 GHz and $[6.9\pm1.1] \times 10^{-4}$ at 150~GHz for the full sample. This is consistent with the values obtained for a sub-sample of active galactic nuclei. For dusty sources, we find 95 per cent upper limits of $\langle p^2 \rangle_{\rm 95}, 10 pages, 5 figures
- Published
- 2019
16. Prediction of Spinal Epidural Metastases
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Kienstra, George E. M., Terwee, Caroline B., Dekker, Friedo W., Canta, Leo R., Borstlap, Aernout C. W., Tijssen, Cees C., Bosch, D. Andries, and Tijssen, Jan G. P.
- Published
- 2000
17. Dark Energy Survey Year 1 Results: Cross-correlation between DES Y1 galaxy weak lensing and SPT+Planck CMB weak lensing
- Author
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Omori, Y., Baxter, E., Chang, C., Kirk, D., Alarcon, A., Bernstein, G. M., Bleem, L. E., Cawthon, R., Choi, A., Chown, R., Crawford, T. M., Davis, C., De Vicente, J., DeRose, J., Dodelson, S., Eifler, T. F., Fosalba, P., Friedrich, O., Gatti, M., Gaztanaga, E., Giannantonio, T., Gruen, D., Hartley, W. G., Holder, G. P., Hoyle, B., Huterer, D., Jain, B., Jarvis, M., Krause, E., MacCrann, N., Miquel, R., Prat, J., Rau, M. M., Reichardt, C. L., Rozo, E., Samuroff, S., S��nchez, C., Secco, L. F., Sheldon, E., Simard, G., Troxel, M. A., Vielzeuf, P., Wechsler, R. H., Zuntz, J., Abbott, T. M. C., Abdalla, F. B., Allam, S., Annis, J., Avila, S., Aylor, K., Benson, B. A., Bertin, E., Bridle, S. L., Brooks, D., Burke, D. L., Carlstrom, J. E., Rosell, A. Carnero, Kind, M. Carrasco, Carretero, J., Castander, F. J., Chang, C. L., Cho, H-M., Crites, A. T., Crocce, M., Cunha, C. E., da Costa, L. N., de Haan, T., Desai, S., Diehl, H. T., Dietrich, J. P., Dobbs, M. A., Everett, W. B., Fernandez, E., Flaugher, B., Frieman, J., Garc��a-Bellido, J., George, E. M., Gruendl, R. A., Gutierrez, G., Halverson, N. W., Harrington, N. L., Hollowood, D. L., Honscheid, K., Holzapfel, W. L., Hou, Z., Hrubes, J. D., James, D. J., Jeltema, T., Kuehn, K., Kuropatkin, N., Lima, M., Lin, H., Lee, A. T., Leitch, E. M., Luong-Van, D., Maia, M. A. G., Manzotti, A., Marrone, D. P., Marshall, J. L., Martini, P., McMahon, J. J., Melchior, P., Menanteau, F., Meyer, S. S., Mocanu, L. M., Mohr, J. J., Natoli, T., Ogando, R. L. C., Padin, S., Plazas, A. A., Pryke, C., Romer, A. K., Roodman, A., Ruhl, J. E., Rykoff, E. S., Sanchez, E., Scarpine, V., Schaffer, K. K., Schindler, R., Sevilla-Noarbe, I., Shirokoff, E., Smith, M., Smith, R. C., Soares-Santos, M., Sobreira, F., Staniszewski, Z., Stark, A. A., Story, K. T., Suchyta, E., Swanson, M. E. C., Tarle, G., Thomas, D., Vanderlinde, K., Vieira, J. D., Vikram, V., Walker, A. R., Weller, J., Williamson, R., Wu, W. L. K., and Zahn, O.
- Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We cross-correlate galaxy weak lensing measurements from the Dark Energy Survey (DES) year-one (Y1) data with a cosmic microwave background (CMB) weak lensing map derived from South Pole Telescope (SPT) and Planck data, with an effective overlapping area of 1289 deg$^{2}$. With the combined measurements from four source galaxy redshift bins, we reject the hypothesis of no lensing with a significance of $10.8\sigma$. When employing angular scale cuts, this significance is reduced to $6.8\sigma$, which remains the highest signal-to-noise measurement of its kind to date. We fit the amplitude of the correlation functions while fixing the cosmological parameters to a fiducial $\Lambda$CDM model, finding $A = 0.99 \pm 0.17$. We additionally use the correlation function measurements to constrain shear calibration bias, obtaining constraints that are consistent with previous DES analyses. Finally, when performing a cosmological analysis under the $\Lambda$CDM model, we obtain the marginalized constraints of $\Omega_{\rm m}=0.261^{+0.070}_{-0.051}$ and $S_{8}\equiv \sigma_{8}\sqrt{\Omega_{\rm m}/0.3} = 0.660^{+0.085}_{-0.100}$. These measurements are used in a companion work that presents cosmological constraints from the joint analysis of two-point functions among galaxies, galaxy shears, and CMB lensing using DES, SPT and Planck data., Comment: 15 pages, 6 figures
- Published
- 2018
18. SOLVING INVERSE STOCHASTIC PROBLEMS FROM DISCRETE PARTICLE OBSERVATIONS USING THE FOKKER--PLANCK EQUATION AND PHYSICS-INFORMED NEURAL NETWORKS.
- Author
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XIAOLI CHEN, LIU YANG, JINQIAO DUAN, and KARNIADAKIS, GEORGE E. M.
- Subjects
INVERSE problems ,PROBABILITY density function ,FOKKER-Planck equation ,EVOLUTION equations ,EQUATIONS - Abstract
The Fokker--Planck (FP) equation governing the evolution of the probability density function (PDF) is applicable to many disciplines, but it requires specification of the coefficients for each case, which can be functions of space-time and not just constants and hence require the development of a data-driven modeling approach. When the data available is directly on the PDF, there exist methods for inverse problems that can be employed to infer the coefficients and thus determine the FP equation and subsequently obtain its solution. Herein, we address a more realistic scenario, where only sparse data are given on the particles' positions at a few time instants, which are not sufficient to accurately construct directly the PDF even at those times from existing methods, e.g., kernel estimation algorithms. To this end, we develop a general framework based on physicsinformed neural networks (PINNs) that introduces a new loss function using the Kullback--Leibler divergence to connect the stochastic samples with the FP equation to simultaneously learn the equation and infer the multidimensional PDF at all times. In particular, we consider two types of inverse problems, type I, where the FP equation is known but the initial PDF is unknown, and type II, in which, in addition to the unknown initial PDF, the drift and diffusion terms are also unknown. In both cases, we investigate problems with either Brownian or L\'evy noise or a combination of both. We demonstrate the new PINN framework in detail in the one-dimensional (1D) case, but we also provide results for up to five dimensions demonstrating that we can infer both the FP equation and dynamics simultaneously at all times with high accuracy using only very few discrete observations of the particles. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
19. A 2500 square-degree CMB lensing map from combined South Pole Telescope and Planck data
- Author
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Omori, Y., Chown, R., Simard, G., Story, K. T., Aylor, K., Baxter, E. J., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H-M., Crawford, T. M., Crites, A. T., de Haan, T., Dobbs, M. A., Everett, W. B., George, E. M., Halverson, N. W., Harrington, N. L., Holder, G. P., Hou, Z., Holzapfel, W. L., Hrubes, J. D., Knox, L., Lee, A. T., Leitch, E. M., Luong-Van, D., Manzotti, A., Marrone, D. P., McMahon, J. J., Meyer, S. S., Mocanu, L. M., Mohr, J. J., Natoli, T., Padin, S., Pryke, C., Reichardt, C. L., Ruhl, J. E., Sayre, J. T., Schaffer, K. K., Shirokoff, E., Staniszewski, Z., Stark, A. A., Vanderlinde, K., Vieira, J. D., Williamson, R., and Zahn, O.
- Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present a cosmic microwave background (CMB) lensing map produced from a linear combination of South Pole Telescope (SPT) and \emph{Planck} temperature data. The 150 GHz temperature data from the $2500\ {\rm deg}^{2}$ SPT-SZ survey is combined with the \emph{Planck} 143 GHz data in harmonic space, to obtain a temperature map that has a broader $\ell$ coverage and less noise than either individual map. Using a quadratic estimator technique on this combined temperature map, we produce a map of the gravitational lensing potential projected along the line of sight. We measure the auto-spectrum of the lensing potential $C_{L}^{\phi\phi}$, and compare it to the theoretical prediction for a $\Lambda$CDM cosmology consistent with the \emph{Planck} 2015 data set, finding a best-fit amplitude of $0.95_{-0.06}^{+0.06}({\rm Stat.})\! _{-0.01}^{+0.01}({\rm Sys.})$. The null hypothesis of no lensing is rejected at a significance of $24\,\sigma$. One important use of such a lensing potential map is in cross-correlations with other dark matter tracers. We demonstrate this cross-correlation in practice by calculating the cross-spectrum, $C_{L}^{\phi G}$, between the SPT+\emph{Planck} lensing map and Wide-field Infrared Survey Explorer (\emph{WISE}) galaxies. We fit $C_{L}^{\phi G}$ to a power law of the form $p_{L}=a(L/L_{0})^{-b}$ with $a=2.15 \times 10^{-8}$, $b=1.35$, $L_{0}=490$, and find $\eta^{\phi G}=0.94^{+0.04}_{-0.04}$, which is marginally lower, but in good agreement with $\eta^{\phi G}=1.00^{+0.02}_{-0.01}$, the best-fit amplitude for the cross-correlation of \emph{Planck}-2015 CMB lensing and \emph{WISE} galaxies over $\sim67\%$ of the sky. The lensing potential map presented here will be used for cross-correlation studies with the Dark Energy Survey (DES), whose footprint nearly completely covers the SPT $2500\ {\rm deg}^2$ field., Comment: 17 pages, 10 figures
- Published
- 2017
20. Millimeter-wave Point Sources from the 2500 Square Degree SPT-SZ Survey: Catalog and Population Statistics.
- Author
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Everett, W. B., Zhang, L., Crawford, T. M., Vieira, J. D., Aravena, M., Archipley, M. A., Austermann, J. E., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Chapman, S., Crites, A. T., de Haan, T., Dobbs, M. A., George, E. M., Halverson, N. W., Harrington, N., Holder, G. P., and Holzapfel, W. L.
- Subjects
DEMOGRAPHIC surveys ,POPULATION statistics ,ACTIVE galactic nuclei ,GALACTIC redshift ,GALAXY clusters - Abstract
We present a catalog of emissive point sources detected in the SPT-SZ survey, a contiguous 2530 square degree area surveyed with the South Pole Telescope (SPT) from 2008–2011 in three bands centered at 95, 150, and 220 GHz. The catalog contains 4845 sources measured at a significance of 4.5σ or greater in at least one band, corresponding to detections above approximately 9.8, 5.8, and 20.4 mJy in 95, 150, and 220 GHz, respectively. The spectral behavior in the SPT bands is used for source classification into two populations based on the underlying physical mechanisms of compact, emissive sources that are bright at millimeter wavelengths: synchrotron radiation from active galactic nuclei and thermal emission from dust. The latter population includes a component of high-redshift sources often referred to as submillimeter galaxies (SMGs). In the relatively bright flux ranges probed by the survey, these sources are expected to be magnified by strong gravitational lensing. The survey also contains sources consistent with protoclusters, groups of dusty galaxies at high redshift undergoing collapse. We cross-match the SPT-SZ catalog with external catalogs at radio, infrared, and X-ray wavelengths and identify available redshift information. The catalog splits into 3980 synchrotron-dominated and 865 dust-dominated sources, and we determine a list of 506 SMGs. Ten sources in the catalog are identified as stars. We calculate number counts for the full catalog, and synchrotron and dusty components, using a bootstrap method and compare our measured counts with models. This paper represents the third and final catalog of point sources in the SPT-SZ survey. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
21. A regulação em saúde no Brasil: um breve exame das décadas de 1999 a 2008 Health regulation in Brazil: a brief survey of the decade from 1999 to 2008
- Author
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George E. M. Kornis, Maria Helena Braga, Marise Fagundes, and Patrícia A. Baumgratz de Paula
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health surveillance ,Brasil ,lcsh:Public aspects of medicine ,pharmaceutical care ,vigilância sanitária ,assistência farmacêutica ,health ,regulation ,lcsh:RA1-1270 ,Agência Nacional de Vigilância Sanitária ,saúde ,regulação ,National Health Surveillance Agency ,lcsh:H1-99 ,lcsh:Social sciences (General) ,Brazil - Abstract
Este artigo discute a experiência brasileira de regulação em saúde no período de 1999 a 2008. Buscou-se compreender as interfaces do processo de regulação em saúde no Brasil, sobretudo com o setor farmacêutico, identificando, historicamente, os atores e contextos referentes a esse processo. A pesquisa baseou-se na revisão bibliográfica e no levantamento das resoluções da diretoria colegiada da Agência Nacional de Vigilância Sanitária. Esse levantamento permitiu identificar a concentração dessas resoluções nas subáreas: medicamentos, recursos humanos e alimentos. No tocante à subárea medicamentos, a concentração se deu em três descritores: registro de medicamentos, boas práticas e substâncias sujeitas a controle especial. Além de fazer uma síntese histórica da evolução da vigilância sanitária brasileira, o artigo focalizou os aspectos regulatórios da Agência Nacional de Vigilância Sanitária e sua relação com a indústria farmacêutica. Portanto, o texto pautou-se pela pretensão de dar resposta à seguinte questão: será que a experiência de regulação da Agência Nacional de Vigilância Sanitária está apta a enfrentar o cenário adverso gerado pela nova crise mundial, especialmente no que se refere ao setor farmacêutico? A principal conclusão do trabalho é de que, apesar dos muitos desafios a serem superados pela Agência Nacional de Vigilância Sanitária no Brasil contemporâneo, a experiência de regulação avançou bastante nesta década. Uma conclusão adicional é que esses avanços constituíram, para o setor farmacêutico, uma proteção face ao quadro adverso gerado pela crise mundial.This paper discusses the Brazilian experience of health regulation from 1999 to 2008. It aims to understand the interfaces of the regulatory process in health in Brazil, particularly the pharmaceutical industry, seeking to identify, historically, the actors and contexts relating to the proceedings. The research was based on literature review and survey of the resolutions of the Board of the National Health Surveillance Agency. This survey identified the concentration of these resolutions in the following areas: drugs, human resources and food. Regarding drugs, emphasis was placed in three key words: drug registration, practices and substances subject to special control. In addition to a brief history of the evolution of Brazilian health surveillance, this paper focused on the regulatory aspects of the National Health Surveillance Agency and its relationship with the pharmaceutical industry. Therefore, the text was guided by the desire to answer the following question: is the experience of regulation of the National Health Surveillance Agency able to cope with the adverse scenario created by the world crisis, especially with regard to the pharmaceutical industry? The main conclusion of this study is that despite the many challenges to be overcome by the National Sanitary Surveillance Agency in Brazil today, the experience of regulation has made good progress in this decade. A further finding is that these developments were, for the pharmaceutical industry, a protection against the adverse situation created by the global crisis.
- Published
- 2011
22. The HARMONI/ELT spectrographs.
- Author
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Rodrigues, M., Capone, J., Earle, A., Foster, T., Hidalgo, A., Lewis, I., Lynn, J., O'brien, K., Tosh, I., George, E. M., Accardo, M., Alvarez, D., Conzelmann, R., Hopgood, J., Clarke, F., Schnetler, H., Tecza, M., and Thatte, N.
- Published
- 2018
- Full Text
- View/download PDF
23. Mass Calibration and Cosmological Analysis of the SPT-SZ Galaxy Cluster Sample Using Velocity Dispersion $\sigma_v$ and X-ray $Y_\textrm{X}$ Measurements
- Author
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Bocquet, S., Saro, A., Mohr, J. J., Aird, K. A., Ashby, M. L. N., Bautz, M., Bayliss, M., Bazin, G., Benson, B. A., Bleem, L. E., Brodwin, M., Carlstrom, J. E., Chang, C. L., Chiu, I., Cho, H. M., Clocchiatti, A., Crawford, T. M., Crites, A. T., Desai, S., de Haan, T., Dietrich, J. P., Dobbs, M. A., Foley, R. J., Forman, W. R., Gangkofner, D., George, E. M., Gladders, M. D., Gonzalez, A. H., Halverson, N. W., Hennig, C., Hlavacek-Larrondo, J., Holder, G. P., Holzapfel, W. L., Hrubes, J. D., Jones, C., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Liu, J., Lueker, M., Luong-Van, D., Marrone, D. P., McDonald, M., McMahon, J. J., Meyer, S. S., Mocanu, L., Murray, S. S., Padin, S., Pryke, C., Reichardt, C. L., Rest, A., Ruel, J., Ruhl, J. E., Saliwanchik, B. R., Sayre, J. T., Schaffer, K. K., Shirokoff, E., Spieler, H. G., Stalder, B., Stanford, S. A., Staniszewski, Z., Stark, A. A., Story, K., Stubbs, C. W., Vanderlinde, K., Vieira, J. D., Vikhlinin, A., Williamson, R., Zahn, O., and Zenteno, A.
- Subjects
Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present a velocity dispersion-based mass calibration of the South Pole Telescope Sunyaev-Zel'dovich effect survey (SPT-SZ) galaxy cluster sample. Using a homogeneously selected sample of 100 cluster candidates from 720 deg2 of the survey along with 63 velocity dispersion ($\sigma_v$) and 16 X-ray Yx measurements of sample clusters, we simultaneously calibrate the mass-observable relation and constrain cosmological parameters. The calibrations using $\sigma_v$ and Yx are consistent at the $0.6\sigma$ level, with the $\sigma_v$ calibration preferring ~16% higher masses. We use the full cluster dataset to measure $\sigma_8(\Omega_ m/0.27)^{0.3}=0.809\pm0.036$. The SPT cluster abundance is lower than preferred by either the WMAP9 or Planck+WMAP9 polarization (WP) data, but assuming the sum of the neutrino masses is $\sum m_\nu=0.06$ eV, we find the datasets to be consistent at the 1.0$\sigma$ level for WMAP9 and 1.5$\sigma$ for Planck+WP. Allowing for larger $\sum m_\nu$ further reconciles the results. When we combine the cluster and Planck+WP datasets with BAO and SNIa, the preferred cluster masses are $1.9\sigma$ higher than the Yx calibration and $0.8\sigma$ higher than the $\sigma_v$ calibration. Given the scale of these shifts (~44% and ~23% in mass, respectively), we execute a goodness of fit test; it reveals no tension, indicating that the best-fit model provides an adequate description of the data. Using the multi-probe dataset, we measure $\Omega_ m=0.299\pm0.009$ and $\sigma_8=0.829\pm0.011$. Within a $\nu$CDM model we find $\sum m_\nu = 0.148\pm0.081$ eV. We present a consistency test of the cosmic growth rate. Allowing both the growth index $\gamma$ and the dark energy equation of state parameter $w$ to vary, we find $\gamma=0.73\pm0.28$ and $w=-1.007\pm0.065$, demonstrating that the expansion and the growth histories are consistent with a LCDM model ($\gamma=0.55; \,w=-1$)., Comment: Accepted by ApJ (v2 is accepted version); 17 pages, 6 figures
- Published
- 2014
24. Changes in the wetlands of hunting creek fairfax county, Virginia
- Author
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Newbury, George E. M.
- Published
- 1981
- Full Text
- View/download PDF
25. A measurement of the secondary-CMB and millimeter-wave-foreground bispectrum using 800 square degrees of South Pole Telescope data
- Author
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Crawford, T. M., Schaffer, K. K., Bhattacharya, S., Aird, K. A., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H-M., Crites, A. T., de Haan, T., Dobbs, M. A., Dudley, J., George, E. M., Halverson, N. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hou, Z., Hrubes, J. D., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Lueker, M., Luong-Van, D., McMahon, J. J., Mehl, J., Meyer, S. S., Millea, M., Mocanu, L. M., Mohr, J. J., Montroy, T. E., Padin, S., Plagge, T., Pryke, C., Reichardt, C. L., Ruhl, J. E., Sayre, J. T., Shaw, L., Shirokoff, E., Spieler, H. G., Staniszewski, Z., Stark, A. A., Story, K. T., van Engelen, A., Vanderlinde, K., Vieira, J. D., Williamson, R., and Zahn, O.
- Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Astrophysics::Instrumentation and Methods for Astrophysics ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We present a measurement of the angular bispectrum of the millimeter-wave sky in observing bands centered at roughly 95, 150, and 220 GHz, on angular scales of $1^\prime \lesssim \theta \lesssim 10^\prime$ (multipole number $1000 \lesssim l \lesssim 10000$). At these frequencies and angular scales, the main contributions to the bispectrum are expected to be the thermal Sunyaev-Zel'dovich (tSZ) effect and emission from extragalactic sources, predominantly dusty, star-forming galaxies (DSFGs) and active galactic nuclei. We measure the bispectrum in 800 $\mathrm{deg}^2$ of three-band South Pole Telescope data, and we use a multi-frequency fitting procedure to separate the bispectrum of the tSZ effect from the extragalactic source contribution. We simultaneously detect the bispectrum of the tSZ effect at $>$10$\sigma$, the unclustered component of the extragalactic source bispectrum at $>$5$\sigma$ in each frequency band, and the bispectrum due to the clustering of DSFGs---i.e., the clustered cosmic infrared background (CIB) bispectrum---at $>$5$\sigma$. This is the first reported detection of the clustered CIB bispectrum. We use the measured tSZ bispectrum amplitude, compared to model predictions, to constrain the normalization of the matter power spectrum to be $\sigma_8 = 0.787 \pm 0.031$ and to predict the amplitude of the tSZ power spectrum at $l = 3000$. This prediction improves our ability to separate the thermal and kinematic contributions to the total SZ power spectrum. The addition of bispectrum data improves our constraint on the tSZ power spectrum amplitude by a factor of two compared to power spectrum measurements alone and demonstrates a preference for a nonzero kinematic SZ (kSZ) power spectrum, with a derived constraint on the kSZ amplitude at $l=3000$ of A_kSZ $ = 2.9 \pm 1.6 \ \mu$K$^2$, or A_kSZ $ = 2.6 \pm 1.8 \ \mu$K$^2$ if the default A_kSZ > 0 prior is removed., Comment: 23 emulateapj pages, 4 figures, revised to match published version. Data products available at http://pole.uchicago.edu/public/data/crawford13
- Published
- 2013
26. A RIESZ BASIS GALERKIN METHOD FOR THE TEMPERED FRACTIONAL LAPLACIAN.
- Author
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ZHIJIANG ZHANG, WEIHUA DENG, and KARNIADAKIS, GEORGE E. M.
- Subjects
RIESZ spaces ,GALERKIN methods ,FRACTIONAL calculus ,LAPLACIAN matrices ,LEVY processes - Abstract
The fractional Laplacian &916;
&946;/2 is the generator of the &946;-stable Lévy process, which is the scaling limit of the Lévy flight. Due to the divergence of the second moment of the jump length of the Lévy flight, it may not be a suitable physical model in many practical applications. However, using a parameter &955; to exponentially temper the isotropic power law measure of the jump length leads to the tempered Lévy flight, which has finite second moment. For a short time the tempered Lévy flight exhibits the dynamics of Lévy flight, while after a sufficiently long time it turns to normal diffusion. The generator of the tempered &946;-stable Lévy process is the tempered fractional Laplacian (&916;+ &955;)&946;/2 [W. H. Deng et al., Multiscale Model. Simul., 16 (2018), pp. 125-149]. In the current work, we present new computational methods for the tempered fractional Laplacian equation, including the cases with the homogeneous and nonhomogeneous generalized Dirichlet type boundary conditions. We prove the well-posedness of the Galerkin weak formulation and provide convergence analysis of the single scaling B-spline and multiscale Riesz bases finite element methods. We propose a technique for efficiently generating the entries of the dense stiffness matrix and for solving the resulting algebraic equation by preconditioning. We also present several numerical experiments to verify the theoretical results. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
27. A COMPUTATIONAL STOCHASTIC METHODOLOGY FOR THE DESIGN OF RANDOM META-MATERIALS UNDER GEOMETRIC CONSTRAINTS.
- Author
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TSANTILI, IVI C., MIN HYUNG CHO, WEI CAI, and KARNIADAKIS, GEORGE E. M.
- Subjects
STOCHASTIC analysis ,ELECTROMAGNETIC wave scattering - Abstract
We present a computational stochastic methodology for generating and optimizing random meta-material (MM) configurations with nonoverlapping geometric constraints subject to various types of covariances and distributions characterizing the randomness of the MM configura- tions. The methodology developed consists of three main components: (1) a deterministic solver for electromagnetic scattering from multiple objects, (2) the Karhunen-Loève (K-L) expansion to represent the correlated configurations of the scattering objects, and (3) the multi-element proba- bilistic collocation method (ME-PCM) to provide flexibility in achieving desired distributions of the MMs. In the current work, we employ random fields from a Spartan family that includes covariance functions with damped oscillatory behavior. The algorithm is applied to study light propagation through random layered heterojunctions and random 3-D MMs. We found that greater transmission and reflection, compared to the uniformly spaced structures, can be achieved for a structure with an oscillatory spacing profile along the propagation direction. Optimized configurations of the hetero- junctions and 3-D MMs have been found with larger or smaller transmission coefficients for different wave numbers of the incoming wave and different correlations. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
28. A SPECTRAL METHOD (OF EXPONENTIAL CONVERGENCE) FOR SINGULAR SOLUTIONS OF THE DIFFUSION EQUATION WITH GENERAL TWO-SIDED FRACTIONAL DERIVATIVE.
- Author
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ZHIPING MAO and KARNIADAKIS, GEORGE E. M.
- Subjects
- *
SINGULAR integrals , *STOCHASTIC convergence , *NUMERICAL solutions to partial differential equations , *FRACTIONAL calculus , *GALERKIN methods , *SOBOLEV spaces - Abstract
An open problem in the numerical solution of fractional partial differential equations (FPDEs) is how to obtain high-order accuracy for singular solutions; even for smooth right-hand sides solutions of FPDEs are singular. Here, we consider the one-dimensional diffusion equation with general two-sided fractional derivative characterized by a parameter p ∊ [0; 1]; for p = 1=2 we recover the Riesz fractional derivative, while for p = 1, 0 we obtain the one-sided fractional derivative. We employ a Petrov-Galerkin projection in a properly weighted Sobolev space with (two-sided) Jacobi polyfracnomials as basis and test functions. In particular, we derive these two-sided Jacobi polyfractonomials as eigenfunctions of a Sturm-Liouville problem with weights uniquely determined by the parameter p. We provide a rigorous analysis and obtain optimal error estimates that depend on the regularity of the forcing term, i.e., for smooth data (corresponding to singular solutions) we obtain exponential convergence, while for smooth solutions we obtain algebraic convergence. We demonstrate the sharpness of our error estimates with numerical examples, and we present comparisons with a competitive spectral collocation method of tunable accuracy. We also investigate numerically deviations from the theory for inhomogeneous Dirichlet boundary conditions as well as for a fractional diffusion-reaction equation. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
29. NUMERICAL GAUSSIAN PROCESSES FOR TIME-DEPENDENT AND NONLINEAR PARTIAL DIFFERENTIAL EQUATIONS.
- Author
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Raissi, Maziar, Perdikaris, Paris, and Karniadakis, George E. M.
- Subjects
PARTIAL differential equations ,GAUSSIAN processes - Abstract
We introduce the concept of numerical Gaussian processes, which we define as Gauss- ian processes with covariance functions resulting from temporal discretization of time-dependent partial differential equations. Numerical Gaussian processes, by construction, are designed to deal with cases where (a) all we observe are noisy data on black-box initial conditions, and (b) we are interested in quantifying the uncertainty associated with such noisy data in our solutions to time- dependent partial differential equations. Our method circumvents the need for spatial discretization of the differential operators by proper placement of Gaussian process priors. This is an attempt to construct structured and data-efficient learning machines, which are explicitly informed by the underlying physics that possibly generated the observed data. The effectiveness of the proposed approach is demonstrated through several benchmark problems involving linear and nonlinear time- dependent operators. In all examples, we are able to recover accurate approximations of the latent solutions, and consistently propagate uncertainty, even in cases involving very long time integration. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
30. The First Public Release of South Pole Telescope Data: Maps of a 95-square-degree Field from 2008 Observations
- Author
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Schaffer, K. K., Crawford, T. M., Aird, K. A., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H. M., Crites, A. T., de Haan, T., Dobbs, M. A., George, E. M., Halverson, N. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hrubes, J. D., Joy, M., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Lueker, M., Luong-Van, D., McMahon, J. J., Mehl, J., Meyer, S. S., Mohr, J. J., Montroy, T. E., Padin, S., Plagge, T., Pryke, C., Reichardt, C. L., Ruhl, J. E., Shirokoff, E., Spieler, H. G., Stalder, B., Staniszewski, Z., Stark, A. A., Story, K., Vanderlinde, K., Vieira, J. D., and Williamson, R.
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Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,FOS: Physical sciences ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation and Methods for Astrophysics (astro-ph.IM) ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
The South Pole Telescope (SPT) has nearly completed a 2500-square-degree survey of the southern sky in three frequency bands. Here we present the first public release of SPT maps and associated data products. We present arcminute-resolution maps at 150 GHz and 220 GHz of an approximately 95-square-degree field centered at R.A. 82.7 degrees, decl. -55 degrees. The field was observed to a depth of approximately 17 micro-K arcmin at 150 GHz and 41 micro-K arcmin at 220 GHz during the 2008 austral winter season. Two variations on map filtering and map projection are presented, one tailored for producing catalogs of galaxy clusters detected through their Sunyaev-Zel'dovich effect signature and one tailored for producing catalogs of emissive sources. We describe the data processing pipeline, and we present instrument response functions, filter transfer functions, and map noise properties. All data products described in this paper are available for download at http://pole.uchicago.edu/public/data/maps/ra5h30dec-55 and from the NASA Legacy Archive for Microwave Background Data Analysis server. This is the first step in the eventual release of data from the full 2500-square-degree SPT survey., 22 pages, 12 figures, matches published version
- Published
- 2011
31. An SZ-selected sample of the most massive galaxy clusters in the 2500-square-degree South Pole Telescope survey
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Williamson, R., Benson, B. A., High, F. W., Vanderlinde, K., Ade, P. A. R., Aird, K. A., Andersson, K., Armstrong, R., Ashby, M. L. N., Bautz, M., Bazin, G., Bertin, E., Bleem, L. E., Bonamente, M., Brodwin, M., Carlstrom, J. E., Chang, C. L., Chapman, S. C., Clocchiatti, A., Crawford, T. M., Crites, A. T., de Haan, T., Desai, S., Dobbs, M. A., Dudley, J. P., Fazio, G. G., Foley, R. J., Forman, W. R., Garmire, G., George, E. M., Gladders, M. D., Gonzalez, A. H., Halverson, N. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hrubes, J. D., Jones, C., Joy, M., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Lueker, M., Luong-Van, D., Marrone, D. P., McMahon, J. J., Mehl, J., Meyer, S. S., Mohr, J. J., Montroy, T. E., Murray, S. S., Padin, S., Plagge, T., Pryke, C., Reichardt, C. L., Rest, A., Ruel, J., Ruhl, J. E., Saliwanchik, B. R., Saro, A., Schaffer, K. K., Shaw, L., Shirokoff, E., Song, J., Spieler, H. G., Stalder, B., Stanford, S. A., Staniszewski, Z., Stark, A. A., Story, K., Stubbs, C. W., Vieira, J. D., Vikhlinin, A., and Zenteno, A.
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Cosmology and Nongalactic Astrophysics (astro-ph.CO) ,Astrophysics::Instrumentation and Methods for Astrophysics ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics::Galaxy Astrophysics ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
The South Pole Telescope (SPT) is currently surveying 2500 deg^2 of the southern sky to detect massive galaxy clusters out to the epoch of their formation using the Sunyaev-Zel'dovich (SZ) effect. This paper presents a catalog of the 26 most significant SZ cluster detections in the full survey region. The catalog includes 14 clusters which have been previously identified and 12 that are new discoveries. These clusters were identified in fields observed to two differing noise depths: 1500 deg^2 at the final SPT survey depth of 18 uK-arcmin at 150 GHz, and 1000 deg^2 at a depth of 54 uK-arcmin. Clusters were selected on the basis of their SZ signal-to-noise ratio (S/N) in SPT maps, a quantity which has been demonstrated to correlate tightly with cluster mass. The S/N thresholds were chosen to achieve a comparable mass selection across survey fields of both depths. Cluster redshifts were obtained with optical and infrared imaging and spectroscopy from a variety of ground- and space-based facilities. The redshifts range from 0.098 \leq z \leq 1.132 with a median of z_med = 0.40. The measured SZ S/N and redshifts lead to unbiased mass estimates ranging from 9.8 \times 10^14 M_sun/h_70 \leq M_200(rho_mean) \leq 3.1 \times 10^15 M_sun/h_70. Based on the SZ mass estimates, we find that none of the clusters are individually in significant tension with the LambdaCDM cosmological model. We also test for evidence of non-Gaussianity based on the cluster sample and find the data show no preference for non-Gaussian perturbations., Main body: 6 tables, 5 figures, 15 pages. Appendix: 26 full-color images, 14 pages. Accepted by ApJ
- Published
- 2011
32. Readiness Assessment Framework for Implementation of Mobile e-Healthcare in Rural South Africa.
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Ilorah, Appolonia I., Ditsa, George E. M., and Mokwena, Sello N.
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ELECTRONIC commerce , *HEALTH care industry , *PREPAREDNESS , *MEDICAL care , *MEDICAL quality control - Abstract
Although healthcare is the biggest service industry in the world, it has yet to realise the full potential of the e-business revolution in the form of e-Healthcare due to many complex challenges. E-Healthcare also does not solve all the problems of rural and remote communities with geographical barriers, because most of the rural and remote areas that e-Healthcare are supposed to help have no electricity connections and other infrastructure needed by e-Healthcare systems. Mobile e-Healthcare removes the restrictions imposed by infrastructure challenged, underserved population, rural geographical locations, wires and cables and enables patients to benefit from increased mobility provided by e-Healthcare. The main objective of this study was therefore to identify e-Healthcare readiness assessment factors in the literature and use them to develop a Mobile e-Healthcare readiness assessment framework for the implementation of Mobile e-Healthcare in rural South Africa health facilities. [ABSTRACT FROM AUTHOR]
- Published
- 2017
33. Prediction of spinal epidural metastases
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Leo R. Canta, George E. M. Kienstra, Caroline B. Terwee, Friedo W. Dekker, Jan G.P. Tijssen, Cees C. Tijssen, D. Andries Bosch, Aernout C. W. Borstlap, Epidemiology and Data Science, AII - Inflammatory diseases, APH - Methodology, and Other departments
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Adult ,Male ,medicine.medical_specialty ,Neurological examination ,Context (language use) ,Myelopathy ,Arts and Humanities (miscellaneous) ,Spinal cord compression ,Risk Factors ,medicine ,Back pain ,Humans ,Medical history ,Prospective Studies ,Prospective cohort study ,Aged ,Pain Measurement ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Spine ,Surgery ,Back Pain ,Female ,Neurology (clinical) ,Radiology ,Epidural Neoplasms ,medicine.symptom ,business ,Spinal Cord Compression - Abstract
Context: Early diagnosis and treatment of spinal epidural metastases (SEM) is of the utmost importance to prevent neurological deficit due to spinal cord compression. Magnetic resonance imaging (MRI) has become the final tool in that diagnostic process. However, access to MRI is still limited in the Netherlands, requiring cost-effective use. It is generally acknowledged that patients with systemic cancer who present with a radiculopathy or myelopathy should undergo an MRI. However, the diagnostic policy in patients with systemic cancer who present with recently developed back pain is still a matter of debate. Objective: To identify the patients with back pain in whom MRI can safely be omitted because of a low risk of SEM. Methods: In a prospective series of 170 consecutive patients with cancer with recently developed back pain, prediction of spinal metastatic disease (SMD) and especially SEM was studied by means of a multivariate risk analysis of the parameters of the standard neurological evaluation (medical history, neurological examination, and plain films of the whole spine). Magnetic resonance imaging was used as the criterion standard. We calculated the risk implications of omitting MRI in patients with an estimated risk below different cutoff points. Results: Spinal metastatic disease was diagnosed in 80 patients (47%); of these, 31 had SEM. A metastatic abnormality on plain films was the strongest independent predictor for SMD. Other important predictors were night pain, progressive pain, and Karnofsky score. Advanced age, exacerbation of pain during recumbency, and osteoporotic fracture imply a low risk of SMD. Night pain and the Karnofsky score proved to be the main predictors for SEM. A plain film showing an osteoporotic fracture strongly decreased the risk of SEM. The discriminating value of the multivariate analysis was too low, and too few patients can be excluded from undergoing MRI on the basis of the standard neurological checkup. To identify all the patients with SMD (P
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- 2000
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34. MULTIFIDELITY INFORMATION FUSION ALGORITHMS FOR HIGH-DIMENSIONAL SYSTEMS AND MASSIVE DATA SETS.
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PERDIKARIS, PARIS, VENTURI, DANIELE, and KARNIADAKIS, GEORGE E. M.
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FUSION (Phase transformation) ,GAUSSIAN processes ,MULTIVARIATE analysis ,ANALYSIS of variance ,DISTRIBUTION (Probability theory) ,MATHEMATICAL models - Abstract
We develop a framework for multifidelity information fusion and predictive inference in high-dimensional input spaces and in the presence of massive data sets. Hence, we tackle simultaneously the "big N" problem for big data and the curse of dimensionality in multivariate parametric problems. The proposed methodology establishes a new paradigm for constructing response surfaces of high-dimensional stochastic dynamical systems, simultaneously accounting for multifidelity in physical models as well as multifidelity in probability space. Scaling to high dimensions is achieved by data-driven dimensionality reduction techniques based on hierarchical functional decompositions and a graph-theoretic approach for encoding custom autocorrelation structure in Gaussian process priors. Multifidelity information fusion is facilitated through stochastic autoregressive schemes and frequency-domain machine learning algorithms that scale linearly with the data. Taking together these new developments leads to linear complexity algorithms as demonstrated in benchmark problems involving deterministic and stochastic fields in up to 10
5 input dimensions and 105 training points on a standard desktop computer. [ABSTRACT FROM AUTHOR]- Published
- 2016
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35. A GENERALIZED SPECTRAL COLLOCATION METHOD WITH TUNABLE ACCURACY FOR VARIABLE-ORDER FRACTIONAL DIFFERENTIAL EQUATIONS.
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FANHAI ZENG, ZHONGQIANG ZHANG, and KARNIADAKIS, GEORGE E. M.
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COLLOCATION methods ,FRACTIONAL differential equations ,JACOBI polynomials ,PARTIAL differential equations ,INTEGRALS ,NUMERICAL analysis - Abstract
We generalize existing Jacobi-Gauss-Lobatto collocation methods for variable-order fractional differential equations using a singular approximation basis in terms of weighted Jacobi polynomials of the form (1 ± x)μP
a,b j (x), where μ > -1. In order to derive the differentiation matrices of the variable-order fractional derivatives, we develop a three-term recurrence relation for both integrals and derivatives of these weighted Jacobi polynomials, hence extending the three-term recurrence relationship of Jacobi polynomials. The new spectral collocation method is applied to solve fractional ordinary and partial differential equations with endpoint singularities. We demonstrate that the singular basis enhances greatly the accuracy of the numerical solution by properly tuning the parameter μ, even for cases where we do not know explicitly the form of singularity in the solution at the boundaries. [ABSTRACT FROM AUTHOR]- Published
- 2015
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36. TIME-SPLITTING SCHEMES FOR FRACTIONAL DIFFERENTIAL EQUATIONS I: SMOOTH SOLUTIONS.
- Author
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WANRONG CAO, ZHONGQIANG ZHANG, and KARNIADAKIS, GEORGE E. M.
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FRACTIONAL differential equations ,SMOOTHNESS of functions ,STOCHASTIC convergence ,NONLINEAR equations ,FRACTIONAL calculus - Abstract
We propose three time-splitting schemes for nonlinear time-fractional differential equations with smooth solutions, where the order of the fractional derivative is 0 < α < 1. While one of the schemes is of order α, the other two schemes are of order 1 + α and 2 - α and thus they can be combined to provide flexible numerical methods with convergence order no less than 3/2. We prove the convergence and stability of the proposed schemes. Numerical examples illustrate the flexibility and the efficiency of these time-splitting schemes and show that they work for multirate and stiff time-fractional differential systems effectively. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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37. TEMPERED FRACTIONAL STURM-LIOUVILLE EIGENPROBLEMS.
- Author
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ZAYERNOURI, MOHSEN, AINSWORTH, MARK, and KARNIADAKIS, GEORGE E. M.
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NUMERICAL solutions to Sturm-Liouville equations ,RANDOM walks ,EIGENFUNCTIONS ,EIGENVALUES ,NUMERICAL solutions to boundary value problems - Abstract
Continuum-time random walk is a general model for particle kinetics, which allows for incorporating waiting times and/or non-Gaussian jump distributions with divergent second moments to account for Lévy flights. Exponentially tempering the probability distribution of the waiting times and the anomalously large displacements results in tempered-stable L´evy processes with finite moments, where the fluid (continuous) limit leads to the tempered fractional diffusion equation. The development of fast and accurate numerical schemes for such nonlocal problems requires a new spectral theory and suitable choice of basis functions. In this study, we introduce two classes of regular and singular tempered fractional Sturm-Liouville problems of two kinds (TFSLP-I and TFSLP-II) of order v ∈ (0, 2). In the regular case, the corresponding tempered differential operators are associated with tempering functions pI (x) = exp(2τ) and pII (x) = exp(-2τ), τ ≥ 0, respectively, in the regular TFSLP-I and TFSLP-II, which do not vanish in [-1, 1]. In contrast, the corresponding differential operators in the singular setting are associated with different forms of pI (x) = exp(2τ)(1-x)1+α(1+ x)1+β and pII (x) = exp(-2τ)(1 - x)1+α(1 + x)1+β, vanishing at x = ±1 in the singular TFSLP-I and TFSLP-II, respectively. The aforementioned tempered fractional differential operators are both of tempered Riemann--Liouville and tempered Caputo type of fractional order μ = v/2 ∈ (0, 1). We prove the well-posedness of the boundary-value problems and that the eigenvalues of the regular tempered problems are real-valued and the corresponding eigenfunctions are orthogonal. Next, we obtain the explicit eigensolutions to TFSLP-I and -II as nonpolynomial functions, which we define as tempered Jacobi poly-fractonomials. These eigenfunctions are orthogonal with respect to the weight function associated with TFSLP-I and -II. Finally, we introduce these eigenfunctions as new basis (and test) functions for spectrally accurate approximation of functions and tempered-fractional differential operators. To this end, we further develop a Petrov-Galerkin spectral method for solving tempered fractional ODEs, followed by the corresponding stability and convergence analysis, which validates the achieved spectral convergence in our simulations. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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38. A MEASUREMENT OF THE SECONDARY-CMB AND MILLIMETER-WAVE-FOREGROUND BISPECTRUM USING 800 deg2 OF SOUTH POLE TELESCOPE DATA.
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Crawford, T. M., Schaffer, K. K., Bhattacharya, S., Aird, K. A., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H-M., Crites, A. T., Haan, T. de, Dobbs, M. A., Dudley, J., George, E. M., Halverson, N. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hou, Z., and Hrubes, J. D.
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GALAXY spectra ,SPECTRUM analysis ,ACTIVE galactic nuclei ,COSMIC background radiation ,EXTRAGALACTIC distances - Abstract
We present a measurement of the angular bispectrum of the millimeter-wave sky in observing bands centered at roughly 95, 150, and 220 GHz, on angular scales of 1′ ≲ θ ≲ 10′ (multipole number 1000 ≲ l ≲ 10,000). At these frequencies and angular scales, the main contributions to the bispectrum are expected to be the thermal Sunyaev-Zel'dovich (tSZ) effect and emission from extragalactic sources, predominantly dusty, star-forming galaxies (DSFGs) and active galactic nuclei. We measure the bispectrum in 800 deg
2 of three-band South Pole Telescope data, and we use a multi-frequency fitting procedure to separate the bispectrum of the tSZ effect from the extragalactic source contribution. We simultaneously detect the bispectrum of the tSZ effect at >10σ, the unclustered component of the extragalactic source bispectrum at >5σ in each frequency band, and the bispectrum due to the clustering of DSFGs—i.e., the clustered cosmic infrared background (CIB) bispectrum—at >5σ. This is the first reported detection of the clustered CIB bispectrum. We use the measured tSZ bispectrum amplitude, compared to model predictions, to constrain the normalization of the matter power spectrum to be σ8 = 0.787 ± 0.031 and to predict the amplitude of the tSZ power spectrum at l = 3000. This prediction improves our ability to separate the thermal and kinematic contributions to the total SZ power spectrum. The addition of bispectrum data improves our constraint on the tSZ power spectrum amplitude by a factor of two compared to power spectrum measurements alone and demonstrates a preference for a nonzero kinematic SZ (kSZ) power spectrum, with a derived constraint on the kSZ amplitude at l = 3000 of AkSZ = 2.9 ± 1.6 μK2 , or AkSZ = 2.6 ± 1.8 μK2 if the default AkSZ > 0 prior is removed. [ABSTRACT FROM AUTHOR]- Published
- 2014
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39. CONSTRAINTS ON COSMOLOGY FROM THE COSMIC MICROWAVE BACKGROUND POWER SPECTRUM OF THE 2500 deg2 SPT-SZ SURVEY.
- Author
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Hou, Z., Reichardt, C. L., Story, K. T., Follin, B., Keisler, R., Aird, K. A., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H.-M., Crawford, T. M., Crites, A. T., Haan, T. de, Putter, R. de, Dobbs, M. A., Dodelson, S., Dudley, J., George, E. M., and Halverson, N. W.
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METAPHYSICAL cosmology ,ASTRONOMY ,COSMIC background radiation ,ASTROPHYSICAL radiation ,PHYSICAL cosmology - Abstract
We explore extensions to the ΛCDM cosmology using measurements of the cosmic microwave background (CMB) from the recent SPT-SZ survey, along with data from WMAP7 and measurements of H
0 and baryon acoustic oscillation (BAO). We check for consistency within ΛCDM between these data sets, and find some tension. The CMB alone gives weak support to physics beyond ΛCDM, due to a slight trend relative to ΛCDM of decreasing power toward smaller angular scales. While it may be due to statistical fluctuation, this trend could also be explained by several extensions. We consider running of the primordial spectral index (dns /dln k), as well as two extensions that modify the damping tail power (the primordial helium abundance Yp and the effective number of neutrino species Neff ) and one that modifies the large-scale power due to the integrated Sachs-Wolfe effect (the sum of neutrino masses ∑mν ). These extensions have similar observational consequences and are partially degenerate when considered simultaneously. Of the six one-parameter extensions considered, we find CMB to have the largest preference for dns /dln k with –0.046 < dns /dln k < –0.003 at 95% confidence, which strengthens to a 2.7σ indication of dns /dln k < 0 from CMB+BAO+H0 . Detectable dns /dln k ≠ 0 is difficult to explain in the context of single-field, slow-roll inflation models. We find Neff = 3.62 ± 0.48 for the CMB, which tightens to Neff = 3.71 ± 0.35 from CMB+BAO+H0 . Larger values of Neff relieve the mild tension between CMB, BAO, and H0 . When the Sunyaev-Zel'dovich selected galaxy cluster abundances () data are also included, we obtain Neff = 3.29 ± 0.31. Allowing for ∑mν gives a 3.0σ detection of ∑mν > 0 from CMB+BAO+H0 +. The median value is (0.32 ± 0.11) eV, a factor of six above the lower bound set by neutrino oscillation observations. All data sets except H0 show some preference for massive neutrinos; data combinations including H0 favor nonzero masses only if BAO data are also included. We also constrain the two-parameter extensions Neff + ∑mν and Neff + Yp to explore constraints on additional light species and big bang nucleosynthesis, respectively. [ABSTRACT FROM AUTHOR]- Published
- 2014
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40. TIME CORRELATION FUNCTIONS OF BROWNIAN MOTION AND EVALUATION OF FRICTION COEFFICIENT IN THE NEAR-BROWNIAN-LIMIT REGIME.
- Author
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CHANGHO KIM and KARNIADAKIS, GEORGE E. M.
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MOLECULAR dynamics , *WIENER processes , *MOMENTUM (Mechanics) , *FRICTION , *STATISTICAL correlation , *ASYMPTOTIC expansions - Abstract
The exponentially decaying behavior of the momentum-momentum and momentumforce time correlation functions of Brownian motion at large times has been extensively used for the numerical evaluation of the friction coefficient γ from molecular dynamics simulations. We perform numerical analysis on these methods and address issues related to the appropriate choice of large time and the rate of convergence of these methods. To this end, we obtain asymptotic expansions of the time correlation functions with respect to the reduced mass μ of the Brownian particle. For two important limit procedures of achieving the Brownian limit, certain forms of the asymptotic expansion of the Mori memory function K(t) are introduced by physical arguments, and then the asymptotic expansions of the time correlation functions are expressed in terms of the limit of K(t), i.e., K0(t) = limμ→∝ K(t), and the next-order correction term K1(t). For the infinite mass limit case, we show that the numerical methods of estimating γ from the exponential decay of the time correlation functions produce γ + O(μ-1), where the first-order correction depends on the microscopic nature of K0(t) (i.e., deviation of K0(t) from the Dirac delta function γδ(t)) as well as the contribution of K1(t) (i.e., deviation of K(t) from K0(t)). We also analyze the ratio of the momentum-force correlation function to the momentum-momentum correlation function, which gives instantaneous exponential decay rate. For the thermodynamic limit case, we consider the Rayleigh gas system to investigate the finite-volume effect due to the boundary conditions and to demonstrate that the lowest-order terms of the asymptotic expansions may fail to describe some characteristic behavior of the time correlation functions. We perform systematic molecular dynamics simulations of the Rayleigh gas system to confirm the theoretical predictions. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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41. COARSE-GRAINED MODELING OF PROTEIN UNFOLDING DYNAMICS.
- Author
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DENG, MINGGE and KARNIADAKIS, GEORGE E. M.
- Subjects
- *
DENATURATION of proteins , *PROTEIN-protein interactions , *COVALENT bonds , *ACTIVATION energy , *MOLECULAR dynamics , *MATHEMATICAL models - Abstract
We present a new dynamic elastic network model (DENM) that describes the unfolding process of a force-loaded protein. The protein interaction network and its potentials are constructed based on information of its native-state structure obtained from the Protein Data Bank, with network nodes positioned at the Cα coordinates of the protein backbone. Specifically, to mimic the unfolding process, i.e., to simulate the process of overcoming the local energy barrier on the free energy landscape with force loading, the noncovalent protein network bonds (i.e., hydrogen bonds, salt bridges, hydrophobic contacts, etc.) are broken one-by-one with a certain probability, while the strong covalent bonds along the backbone (i.e., peptide bonds, disulfide bonds, etc.) are kept intact. The jumping event from local energy minima (bonds breaking rate) are chosen according to Kramer's theory and the Bell model. Moreover, we exploit the self-similar structure of proteins at different scales to design an effective coarse-graining procedure for DENM with optimal parameter selection. The robustness of DENM is validated by coarse-grained molecular dynamics (MD) simulation against atomistic MD simulation of force-extension processes of the Fibrinogen and Titin Immunoglobulin proteins. We observe that the native structure of the proteins determines the total unfolding dynamics (including large deviations) and not just the fluctuations around the native state. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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42. A MEASUREMENT OF THE COSMIC MICROWAVE BACKGROUND DAMPING TAIL FROM THE 2500-SQUARE-DEGREE SPT-SZ SURVEY.
- Author
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Story, K. T., Reichardt, C. L., Hou, Z., Keisler, R., Aird, K. A., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H.-M., Crawford, T. M., Crites, A. T., Haan, T. de, Dobbs, M. A., Dudley, J., Follin, B., George, E. M., Halverson, N. W., Holder, G. P., and Holzapfel, W. L.
- Subjects
COSMIC background radiation ,METAPHYSICAL cosmology ,ANISOTROPY ,BARYON spectra ,GRAVITATIONAL lenses - Abstract
We present a measurement of the cosmic microwave background (CMB) temperature power spectrum using data from the recently completed South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) survey. This measurement is made from observations of 2540 deg
2 of sky with arcminute resolution at 150 GHz, and improves upon previous measurements using the SPT by tripling the sky area. We report CMB temperature anisotropy power over the multipole range 650 < ℓ < 3000. We fit the SPT bandpowers, combined with the 7 yr Wilkinson Microwave Anisotropy Probe (WMAP7) data, with a six-parameter ΛCDM cosmological model and find that the two datasets are consistent and well fit by the model. Adding SPT measurements significantly improves ΛCDM parameter constraints; in particular, the constraint on θs tightens by a factor of 2.7. The impact of gravitational lensing is detected at 8.1σ, the most significant detection to date. This sensitivity of the SPT+WMAP7 data to lensing by large-scale structure at low redshifts allows us to constrain the mean curvature of the observable universe with CMB data alone to be . Using the SPT+WMAP7 data, we measure the spectral index of scalar fluctuations to be ns = 0.9623 ± 0.0097 in the ΛCDM model, a 3.9σ preference for a scale-dependent spectrum with ns < 1. The SPT measurement of the CMB damping tail helps break the degeneracy that exists between the tensor-to-scalar ratio r and ns in large-scale CMB measurements, leading to an upper limit of r < 0.18 (95% C.L.) in the ΛCDM+r model. Adding low-redshift measurements of the Hubble constant (H0 ) and the baryon acoustic oscillation (BAO) feature to the SPT+WMAP7 data leads to further improvements. The combination of SPT+WMAP7+H0 +BAO constrains ns = 0.9538 ± 0.0081 in the ΛCDM model, a 5.7σ detection of ns < 1, and places an upper limit of r < 0.11 (95% C.L.) in the ΛCDM+r model. These new constraints on ns and r have significant implications for our understanding of inflation, which we discuss in the context of selected single-field inflation models. [ABSTRACT FROM AUTHOR]- Published
- 2013
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43. EXTRAGALACTIC MILLIMETER-WAVE POINT-SOURCE CATALOG, NUMBER COUNTS AND STATISTICS FROM 771 deg2 OF THE SPT-SZ SURVEY.
- Author
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Mocanu, L. M., Crawford, T. M., Vieira, J. D., Aird, K. A., Aravena, M., Austermann, J. E., Benson, B. A., Béthermin, M., Bleem, L. E., Bothwell, M., Carlstrom, J. E., Chang, C. L., Chapman, S., Cho, H.-M., Crites, A. T., Haan, T. de, Dobbs, M. A., Everett, W. B., George, E. M., and Halverson, N. W.
- Subjects
ACTIVE galactic nuclei ,EXTRAGALACTIC distances ,REDSHIFT ,SYNCHROTRON radiation ,GALAXIES - Abstract
We present a point-source catalog from 771 deg
2 of the South Pole Telescope Sunyaev-Zel'dovich survey at 95, 150, and 220 GHz. We detect 1545 sources above 4.5σ significance in at least one band. Based on their relative brightness between survey bands, we classify the sources into two populations, one dominated by synchrotron emission from active galactic nuclei, and one dominated by thermal emission from dust-enshrouded star-forming galaxies. We find 1238 synchrotron and 307 dusty sources. We cross-match all sources against external catalogs and find 189 unidentified synchrotron sources and 189 unidentified dusty sources. The dusty sources without counterparts are good candidates for high-redshift, strongly lensed submillimeter galaxies. We derive number counts for each population from 1 Jy down to roughly 11, 4, and 11 mJy at 95, 150, and 220 GHz. We compare these counts with galaxy population models and find that none of the models we consider for either population provide a good fit to the measured counts in all three bands. The disparities imply that these measurements will be an important input to the next generation of millimeter-wave extragalactic source population models. [ABSTRACT FROM AUTHOR]- Published
- 2013
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44. A COSMIC MICROWAVE BACKGROUND LENSING MASS MAP AND ITS CORRELATION WITH THE COSMIC INFRARED BACKGROUND.
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HOLDER, G. P., VIERO, M. P., ZAHN, O., AIRD, K. A., BENSON, B. A., BHATTACHARYA, S., BLEEM, L. E., BOCK, J., BRODWIN, M., CARLSTROM, J. E., C. L. CHANG, H-M. CHO, CONLEY, A., CRAWFORD, T. M., CRITES, A. T., DE HAAN, T., DOBBS, M. A., DUDLEY, J., GEORGE, E. M., and HALVERSON, N. W.
- Published
- 2013
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45. THE FIRST PUBLIC RELEASE OF SOUTH POLE TELESCOPE DATA: MAPS OF A 95 deg² FIELD FROM 2008 OBSERVATIONS.
- Author
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Schaffer, K. K., Crawford, T. M., Aird, K. A., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H. M., Crites, A. T., De Haan, T., Dobbs, M. A., George, E. M., Halverson, N. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hrubes, J. D., Joy, M., Keisler, R., and Knox, L.
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ELECTRONIC data processing management ,GALAXY clusters ,LARGE astronomical telescopes ,EMISSIVITY - Abstract
The South Pole Telescope (SPT) has nearly completed a 2500 deg² survey of the southern sky in three frequency bands. Here, we present the first public release of SPT maps and associated data products. We present arcminute-resolution maps at 150 GHz and 220 GHz of an approximately 95 deg² field centered at R.A. 82°.17, decl.-55°. The field was observed to a depth of approximately 17 µK arcmin at 150 GHz and 41 µK arcmin at 220 GHz during the 2008 austral winter season. Two variations on map filtering and map projection are presented, one tailored for producing catalogs of galaxy clusters detected through their Sunyaev-Zel'dovich effect signature and one tailored for producing catalogs of emissive sources. We describe the data processing pipeline, and we present instrument response functions, filter transfer functions, and map noise properties. All data products described in this paper are available for download at http://pole.uchicago.edu/public/data/maps/ra5h30dec-55 and from the NASA Legacy Archive for Microwave Background Data Analysis server. This is the first step in the eventual release of data from the full 2500 deg² SPT survey. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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46. A MEASUREMENT OF THE DAMPING TAIL OF THE COSMIC MICROWAVE BACKGROUND POWER SPECTRUM WITH THE SOUTH POLE TELESCOPE.
- Author
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Keisler, R., Reichardt, C. L., Aird, K. A., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H. M., Crawford, T. M., Crites, A. T., De Haan, T., Dobbs, M. A., Dudley, J., George, E. M., Halverson, N. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hou, Z., and Hrubes, J. D.
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COSMIC background radiation ,NEUTRINOS ,HELIUM ,HUBBLE constant ,REDSHIFT ,GALAXY clusters - Abstract
We present a measurement of the angular power spectrum of the cosmic microwave background (CMB) using data from the South Pole Telescope (SPT). The data consist of 790 deg² of sky observed at 150 GHz during 2008 and 2009. Here we present the power spectrum over the multipole range 650 < ℓ < 3000, where it is dominated by primary CMB anisotropy. We combine this power spectrum with the power spectra from the seven-year Wilkinson Microwave Anisotropy Probe (WMAP) data release to constrain cosmological models. We find that the SIM and WMAP data are consistent with each other and, when combined, are well fit by a spatially flat, ACDM cosmological model. The SVT+WMAP constraint on the spectral index of scalar fluctuations is n
s = 0.9663 ± 0.0112. We detect, at ~5σ significance, the effect of gravitational lensing on the CMB power spectrum, and find its amplitude to be consistent with the ACDM cosmological model. We explore a number of extensions beyond the ACDM model. Each extension is tested independently, although there are degeneracies between some of the extension parameters We constrain the tensor-to-scalar ratio to be r < 0.21 (95% CL) and constrain the running of the scalar spectral index to be dns /d lnk = -0.024 ± 0.013. We strongly detect the effects of primordial helium and neutrinos on the CMB; a model without helium is rejected at 7.7σ, while a model without neutrinos is rejected at 7.5σ. The primordial helium abundance is measured to be Yp = 0.296 ± 0.030, and the effective number of relativistic. species is measured to be Neff = 3.85 ± 0.62. The constraints on these models are strengthened when the CMB data are combined with measurements of the Hubble constant and the baryon acoustic oscillation feature. Notable improvements include ns = 0.9668 ± 0.0093, r < 0.17 (95% CL), and Neff = 3.86 ± 0.42. The SPT+WMAP data show a mild preference for low power in the CMB damping tail, and while this preference may be accommodated by models that have a negative spectral running, a high primordial helium abundance, or a high effective number of relativistic species, such models are disfavored by the abundance of low-redshift galaxy clusters. [ABSTRACT FROM AUTHOR]- Published
- 2011
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47. X-RAY PROPERTIES OF THE FIRST SUNYAEV-ZEL'DOVICH EFFECT SELECTED GALAXY CLUSTER SAMPLE FROM THE SOUTH POLE TELESCOPE.
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ANDERSSON, K., BENSON, B. A., ADE, P. A. R., AIRD, K. A., ARMSTRONG, B., BAUTZ, M., BLEEM, L. E., BRODWIN, M., CARLSTROM, J. E., CHANG, C. L., CRAWFORD, T. M., CRITES, A. T., DE HAAN, T., DESAI, S., DOBBS, M. A., DUDLEY, J. P., FOLEY, R. J., FORMAN, W. R., GARMIRE, G., and GEORGE, E. M.
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GALAXY clusters ,X-ray astronomy ,COSMIC background radiation ,TELESCOPES ,REDSHIFT - Abstract
We present results of X-ray observations of a sample of 15 clusters selected via their imprint on the cosmic microwave background from the thermal Sunyaev-Zel'dovich (SZ) effect. These clusters are a subset of the first SZ-selected cluster catalog, obtained from observations of 178 deg² of sky surveyed by the South Pole Telescope (SPT). Using X-ray observations with Chandra and XMM-Newton, we estimate the temperature, T
X , and mass, Mg , of the intracluster medium within r500 for each cluster. From these, we calculate YX = Mg TX and estimate the total cluster mass using an M500 -YX scaling relation measured from previous X-ray studies. The integrated Comptonization, YSZ . is derived from the SZ measurements, using additional information from the X-ray-measured gas density profiles and a universal temperature profile. We calculate scaling relations between the X-ray and SZ observables and find results generally consistent with other measurements and the expectations from simple self-similar behavior. Specifically, we fit a YSZ -YX relation and find a normalization of 0.82 ± 0.07, marginally consistent with the predicted ratio of YSZ /YX - 0.91 ± 0.01 that would be expected from the density and temperature models used in this work. Using the YX -derived mass estimates, we fit a YSZ -M500 relation and find a slope consistent with the self-similar expectation of YSZ ∝ M5/3 with a normalization consistent with predictions from other X-ray studies. We find that the SZ mass estimates, derived from cosmological simulations of the SPT survey, are lower by a factor of 0.78 ± 0.06 relative to the X-ray mass estimates. This offset is at a level of 1.3σ when considering the ~15% systematic uncertainty for the simulation-based SZ masses. Overall, the X-ray measurements confirm that the scaling relations of the SZ-selected clusters are consistent with the properties of other X-ray-selected samples of massive clusters, even allowing for the broad redshift range (0.29 < z < 1.08) of the sample. [ABSTRACT FROM AUTHOR]- Published
- 2011
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- View/download PDF
48. IMPROVED CONSTRAINTS ON COSMIC MICROWAVE BACKGROUND SECONDARY ANISOTROPIES FROM THE COMPLETE 2008 SOUTH POLE TELESCOPE DATA.
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SHIROKOFF, E., REICHARDT, C. L., SHAW, L., MILLEA, M., ADE, P. A. R., AIRD, K. A., BENSON, B. A., BLEEM, L. E., CARLSTROM, J. E., CHANG, C. L., CHO, H. M., CRAWFORD, T. M., CRITES, A. T., DE HAAN, T., DOBBS, M. A., DUDLEY, J., GEORGE, E. M., HALVERSON, N. W., HOLDER, G. P., and HOLZAPFEL, W. L.
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COSMIC background radiation ,TELESCOPES ,ANISOTROPY ,GALAXY spectra ,ASTRONOMICAL observations - Abstract
We report measurements of the cosmic microwave background (CMB) power spectrum from the complete 2008 South Pole Telescope (SPT) data set. We analyze twice as much data as the first SPT power spectrum analysis, using an improved cosmological parameter estimator which fits multi-frequency models to the SPT 150 and 220 GHz bandpowers. We find an excellent fit to the measured bandpowers with a model that includes lensed primary CMB anisotropy, secondary thermal (tSZ) and kinetic (kSZ) Sunyaev-Zel'dovich anisotropies, unclustered synchrotron point sources, and clustered dusty point sources. In addition to measuring the power spectrum of dusty galaxies at high signal-to-noise, the data primarily constrain a linear combination of the kSZ and tSZ anisotropy contributions at 150 GHz and Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. The 95% confidence upper limits on secondary anisotropy power are Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. and Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. We also consider the potential correlation of dusty and tSZ sources and find it incapable of relaxing the tSZ upper limit. These results increase the significance of the lower than expected tSZ amplitude previously determined from SPT power spectrum measurements. We find that models including non-thermal pressure support in groups and clusters predict tSZ power in better agreement with the SPT data. Combining the tSZ power measurement with primary CMB data halves the statistical uncertainty on or8. However, the preferred value of σ
8 varies significantly between tSZ models. Improved constraints on cosmological parameters from tSZ power spectrum measurements require continued progress in the modeling of the tSZ power. [ABSTRACT FROM AUTHOR]- Published
- 2011
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49. Progress on ANL/KICP Bolometers for SPTpol.
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Crites, A. T., Benson, B. A., Bleem, L., Carlstrom, J. E., Chang, C. L., Datesman, A., Divan, R., George, E. M., Holzapfel, W. L., Lee, A., Lueker, M., McMahon, J. J., Mehl, J., Meyer, S. S., Montroy, T., Natoli, T., Novosad, V., Pearson, J., Ruhl, J., and Sayre, J.
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BOLOMETERS ,OPTICAL measurements ,OPTICAL detectors ,MICROFABRICATION ,TEMPERATURE measurements ,COSMIC background radiation - Abstract
We present progress on Argonne/KICP TES bolometers fabricated at Argonne National Labs. These detectors will be used to measure the polarization of the Cosmic Microwave Background radiation with SPTpol. The sensors are bolometers consisting of a Mo/Au transition edge sensors (TES) suspended on silicon nitride with a gold bar absorber to couple radiation to the device. We present optical measurements and thermal characterizations of prototype devices. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
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50. Stability of Al-Mn Transition Edge Sensors for Frequency Domain Multiplexing.
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Hubmayr, J., Austermann, J. E., Beall, J. A., Becker, D., Bennett, D. A., Benson, B. A., Bleem, L. E., Chang, C. L., Carlstrom, J. E., Cho, H.-M., Crites, A. T., Dobbs, M., Everett, W., George, E. M., Holzapfel, W. L., Halverson, N. W., Henning, J. W., Hilton, G. C., Irwin, K. D., and Li, D.
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MULTIPLEXING ,STABILITY (Mechanics) ,BOLOMETERS ,MANGANESE alloys ,TEMPERATURE measurements ,POLARISCOPE ,INTEGRATED circuits ,MICROFABRICATION - Abstract
We are developing arrays of 150 GHz transition edge sensor (TES) polarimeters for the South Pole Telescope polarimeter (SPTpol). Prototype devices use an aluminum manganese (Al-Mn) alloy TES with a normal resistance Rn suited to frequency domain multiplexing (fMUX) used in SPTpol. Using the fMUX readout, the devices exhibit noise performance consistent with expectations when R>0.8Rn. Below 0.8Rn, the detectors have high loopgain and become unstable, which is predicted by use of a compound TES model. We address this issue in a recent fabrication with increased TES heat capacity and normal metal structures on the TES to tune the temperature sensitivity. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
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