Thomas P. Downes
California Institute of Technology
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Thomas P. Downes.
The Astrophysical Journal | 2013
A. Weiß; C. De Breuck; D. P. Marrone; J. D. Vieira; James E. Aguirre; K. A. Aird; M. Aravena; M. L. N. Ashby; Matthew B. Bayliss; B. A. Benson; M. Béthermin; A. D. Biggs; L. E. Bleem; J. J. Bock; M. Bothwell; C. M. Bradford; M. Brodwin; J. E. Carlstrom; C. L. Chang; Sydney Chapman; T. M. Crawford; A. T. Crites; T. de Haan; M. Dobbs; Thomas P. Downes; C. D. Fassnacht; E. M. George; Michael D. Gladders; Anthony H. Gonzalez; T. R. Greve
Using the Atacama Large Millimeter/submillimeter Array, we have conducted a blind redshift survey in the 3 mm atmospheric transmission window for 26 strongly lensed dusty star-forming galaxies (DSFGs) selected with the South Pole Telescope. The sources were selected to have S_(1.4mm) > 20 mJy and a dust-like spectrum and, to remove low-z sources, not have bright radio (S_843MHz) 3. We discuss the effect of gravitational lensing on the redshift distribution and compare our measured redshift distribution to that of models in the literature.
The Astrophysical Journal | 2013
Jack Sayers; Nicole G. Czakon; A. Mantz; S. R. Golwala; Silvia Ameglio; Thomas P. Downes; Patrick M. Koch; Kai-Yang Lin; Ben J Maughan; Sandor M. Molnar; Leonidas A. Moustakas; Tony Mroczkowski; E. Pierpaoli; Jennifer A. Shitanishi; Seth Siegel; Keiichi Umetsu; N. van der Pyl
We describe Sunyaev-Zel’dovich (SZ) effect measurements and analysis of the intracluster medium (ICM) pressure profiles of a set of 45 massive galaxy clusters imaged using Bolocam at the Caltech Submillimeter Observatory. We deproject the average pressure profile of our sample into 13 logarithmically spaced radial bins between 0.07R500 and 3.5R500, and we find that a generalized Navarro, Frenk, and White (gNFW) profile describes our data with sufficient goodness-of-fit and best-fit parameters (C500, �, �, , P0 = 1.18, 0.86, 3.67, 0.67, 4.29). We use X-ray data to define cool-core and disturbed subsamples of clusters, and we constrain the average pressure profiles of each of these subsamples. We find that, given the precision of our data, the average pressure profiles of disturbed and cool-core clusters are consistent with one another at R & 0.15R500, with cool-core systems showing indications of higher pressure at R . 0.15R500. In addition, for the first time, we place simultaneous constraints on the mass scaling of cluster pressure profiles, their ensemble mean profile, and their radius-dependent intrinsic scatter between 0.1R500 and 2.0R500. The scatter among profiles is minimized at radii between ≃ 0.2R500 and ≃ 0.5R500, with a value of ≃ 20%. These results for the intrinsic scatter are largely consistent with previous analyses, most of which have relied heavily on X-ray derived pressures of clusters at significantly lower masses and redshifts compared to our sample. Therefore, our data provide further evidence that cluster pressure profiles are largely universal with scatter of ≃ 20–40% about the universal profile over a wide range of masses and redshifts. Subject headings: galaxies: clusters: general — galaxies: clusters: intracluster medium
The Astrophysical Journal | 2012
T. R. Greve; J. D. Vieira; A. Wei; James E. Aguirre; K. A. Aird; M. L. N. Ashby; B. A. Benson; L. E. Bleem; C. M. Bradford; Mark Brodwin; J. E. Carlstrom; C. L. Chang; S. C. Chapman; T. M. Crawford; C. De Breuck; T. de Haan; M. Dobbs; Thomas P. Downes; C. D. Fassnacht; G. G. Fazio; E. M. George; Michael D. Gladders; Anthony H. Gonzalez; N. W. Halverson; Yashar D. Hezaveh; F. W. High; G. P. Holder; W. L. Holzapfel; S. Hoover; J. D. Hrubes
We present APEX SABOCA 350 μm and LABOCA 870 μm observations of 11 representative examples of the rare, extremely bright (_( 1.4 mm) > 15 mJy), dust-dominated millimeter-selected galaxies recently discovered by the South Pole Telescope. All 11 sources are robustly detected with LABOCA with 40 mJy 3σ, with the detections or upper limits providing a key constraint on the shape of the spectral energy distribution (SED) near its peak. We model the SEDs of these galaxies using a simple modified blackbody and perform the same analysis on samples of SMGs of known redshift from the literature. These calibration samples inform the distribution of dust temperature for similar SMG populations, and this dust temperature prior allows us to derive photometric redshift estimates and far-infrared luminosities for the sources. We find a median redshift of z = 3.0, higher than the z = 2.2 inferred for the normal SMG population. We also derive the apparent size of the sources from the temperature and apparent luminosity, finding them to appear larger than our unlensed calibration sample, which supports the idea that these sources are gravitationally magnified by massive structures along the line of sight.
The Astrophysical Journal | 2015
Nicole G. Czakon; Jack Sayers; A. Mantz; S. R. Golwala; Thomas P. Downes; Patrick M. Koch; Kai-Yang Lin; Sandor M. Molnar; Leonidas A. Moustakas; Tony Mroczkowski; E. Pierpaoli; Jennifer A. Shitanishi; Seth Siegel; Keiichi Umetsu
We present scaling relations between the integrated Sunyaev-Zeldovich Effect (SZE) signal,
Proceedings of SPIE | 2010
Ran Duan; Sean McHugh; B. Serfass; Benjamin A. Mazin; Andrew Merrill; S. R. Golwala; Thomas P. Downes; Nicole G. Czakon; Peter K. Day; Jiansong Gao; J. Glenn; Matthew I. Hollister; H. G. LeDuc; Philip R. Maloney; Hien T. Nguyen; Jack Sayers; James A. Schlaerth; Seth Siegel; John E. Vaillancourt; Anastasios Vayonakis; Philip R. Wilson; Jonas Zmuidzinas
Y_{rm SZ}
The Astrophysical Journal | 2013
M. Bothwell; James E. Aguirre; S. C. Chapman; D. P. Marrone; J. D. Vieira; M. L. N. Ashby; M. Aravena; B. A. Benson; J. J. Bock; C. M. Bradford; M. Brodwin; J. E. Carlstrom; T. M. Crawford; C. De Breuck; Thomas P. Downes; C. D. Fassnacht; Anthony H. Gonzalez; T. R. Greve; B. Gullberg; Yashar D. Hezaveh; G. P. Holder; W. L. Holzapfel; E. Ibar; R. J. Ivison; J. Kamenetzky; R. Keisler; R. Lupu; J. Ma; M. Malkan; V. McIntyre
, its X-ray analogue,
Proceedings of SPIE | 2010
Philip R. Maloney; Nicole G. Czakon; Peter K. Day; Thomas P. Downes; Ran Duan; Jiansong Gao; J. Glenn; S. R. Golwala; Matt I. Hollister; H. G. LeDuc; Benjamin A. Mazin; Sean McHugh; Hien T. Nguyen; Jack Sayers; James A. Schlaerth; Seth Siegel; John E. Vaillancourt; Anastasios Vayonakis; Philip R. Wilson; Jonas Zmuidzinas
Y_{rm X}equiv M_{rm gas}T_{rm X}
The Astrophysical Journal | 2013
Jack Sayers; Tony Mroczkowski; Nicole G. Czakon; S. R. Golwala; A. Mantz; Silvia Ameglio; Thomas P. Downes; Patrick M. Koch; Kai-Yang Lin; Sandor M. Molnar; Leonidas A. Moustakas; Stephen Muchovej; E. Pierpaoli; Jennifer A. Shitanishi; Seth Siegel; Keiichi Umetsu
, and total mass,
Proceedings of SPIE | 2012
S. R. Golwala; Clint Bockstiegel; Spencer Brugger; Nicole G. Czakon; Peter K. Day; Thomas P. Downes; Ran Duan; Jiansong Gao; Amandeep K. Gill; J. Glenn; Matthew I. Hollister; H. G. LeDuc; Philip R. Maloney; Benjamin A. Mazin; Sean McHugh; David P. Miller; Hien T. Nguyen; Jack Sayers; James A. Schlaerth; Seth Siegel; Anastasios Vayonakis; Philip R. Wilson; Jonas Zmuidzinas
M_{rm tot}
Proceedings of SPIE | 2010
James A. Schlaerth; Nicole G. Czakon; Peter K. Day; Thomas P. Downes; Ran Duan; Jiansong Gao; J. Glenn; S. R. Golwala; Matthew I. Hollister; H. G. LeDuc; Benjamin A. Mazin; Philip R. Maloney; Hien T. Nguyen; Jack Sayers; Seth Siegel; John E. Vaillancourt; Anastasios Vayonakis; Philip R. Wilson; Jonas Zmuidzinas
, for the 45 galaxy clusters in the Bolocam X-ray-SZ (BOXSZ) sample. All parameters are integrated within