DSpace Angular :: Browsing by Author "Rosati, P."

Browsing by Author "Rosati, P."

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CLASH : A CENSUS OF MAGNIFIED STAR-FORMING GALAXIES AT z similar to 6-8
(2014) Bradley, L.; Zitrin, A.; Coe, D.; Bouwens, R.; Postman, M.; Balestra, I.; Grillo, C.; Monna, A.; Rosati, P.; Carrasco, M.
CLASH : Accurate photometric redshifts with 14 HST bands in massive galaxy cluster cores
(2017) Lazkoz, R.; Lemze, D.; Maoz, D.; Mercurio, A.; Meneghetti, M.; Merten, J.; Moustakas, L.; Nonino, M.; Orgaz, S.; Infante Lira, Leopoldo; Riess, A.; Rodney, S.; Sayers, J.; Umetsu, K.; Zheng, W.; Zitrin, A.; Molino, A.; Benítez, N.; Ascaso, B.; Coe, D.; Postman M.; Jouvel, S.; Host, O.; Lahav O.; Seitz, S.; Medezinski, E.; Rosati, P.; Schoenell, W.; Koekemoer, A.; Jiménez-Teja, Y.; Broadhurst, T.; Melchior, P.; Balestra, I.; Bartelmann, M.; Bouwens, R.; Bradley, L.; Czakon, N.; Donahue, M.; Ford, H.; Graur, O.; Graves, G.; Grillo, C.; Jha, S.; Kelson, D.
Clash : Extending galaxy strong lensing to small physical scales with distant sources highly magnified by galaxy cluster members
(2014) Grillo, C.; Gobat, R.; Presotto, V.; Balestra, I.; Mercurio, A.; Rosati, P.; Nonino, M.; Vanzella, E.; Christensen, L.; Infante Lira, Leopoldo
CLASH-VLT : The stellar mass function and stellar mass density profile of the z = 0.44 cluster of galaxies MACS J1206.2-0847
(2014) Annunziatella, M.; Biviano, A.; Mercurio, A.; Nonino, M.; Rosati, P.; Balestra, I.; Presotto, V.; Girardi, M.; Gobat, R.; Infante Lira, Leopoldo
CLASH-VLT: spectroscopic confirmation of z=6.11 quintuply lensed galaxy in the Frontier Fields cluster RXC J2248.7-4431
(2013) Balestra, I.; Vanzella, E.; Rosati, P.; Monna, A.; Grillo, C.; Nonino, M.; Mercurio, A.; Biviano, A.; Bradley, L.; Coe, D.; Fritz, A.; Postman, M.; Seitz, S.; Scodeggio, M.; Tozzi, P.; Zhengll, W.; Ziegler, B.; Zitrin, A.; Annunziatella, M.; Bartelmann, M.; Benitez, N.; Broadhurst, T.; Bouwens, R.; Czoske, O.; Donahue, M.; Ford, H.; Girardi, M.; Infante, L.; Jouvel, S.; Kelson, D.; Koekemoer, A.; Kuchner, U.; Lemze, D.; Lombardi, M.; Maier, C.; Medezinski, E.; Melchior, P.; Meneghetti, M.; Merten, J.; Molino, A.; Moustakas, L.; Presotto, V.; Smit, R.; Umetsu, K.
We present VIsible Multi-Object Spectrograph (VIMOS) observations of a z similar to 6 galaxy quintuply imaged by the Frontier Fields galaxy cluster RXC J2248.7-4431 (z = 0.348). This sub-L*, high-z galaxy has been recently discovered by Monna et al. (2013) using dropout techniques with the 16-band HST photometry acquired as part of the Cluster Lensing And Supernova survey with Hubble (CLASH). Obtained as part of the CLASH-VLT survey, the VIMOS medium-resolution spectra of this source show a very faint continuum between similar to 8700 angstrom and similar to 9300 angstrom and a prominent emission line at 8643 angstrom, which can be readily identified with Lyman-alpha at z = 6.110 +/- 0.002. The emission line exhibits an asymmetric profile, with a more pronounced red wing. The rest-frame equivalent width of the line is EW = 79 +/- 10 angstrom, relatively well constrained thanks to the detection of the UV continuum, which is rarely achieved for a sub-L* galaxy at this redshift. After correcting for magnification, the star formation rate (SFR) estimated from the Ly alpha line is SFR(Ly alpha) = 11 M-circle dot yr(-l) and that estimated from the UV data is SFR(UV) = 3 M-circle dot yr(-1). We estimate that the effective radius of the source is R-e less than or similar to 0.4 kpc, which implies a star formation surface mass density Sigma(SFR) > 6 M(circle dot)yr(-1) kpc(-2) and, using the Kennicutt-Schmidt relation, a gas surface mass density Sigma(gas) > 10(3) M(circle dot)pc(-2). Our results support the idea that this magnified, distant galaxy is a young and compact object with luminosity 0.4 L* at z = 6, when the Universe was just 1 Gyr old, with a similar amount of mass in gas and stars. In the spirit of the Frontier Fields initiative, we also publish the redshifts of several multiply imaged sources and other background objects, which will help improving the strong-lensing model of this galaxy cluster.
CLASH: THE ENHANCED LENSING EFFICIENCY OF THE HIGHLY ELONGATED MERGING CLUSTER MACS J0416.1-2403
(2013) Zitrin, A.; Meneghetti, M.; Umetsu, K.; Broadhurst, T.; Bartelmann, M.; Bouwens, R.; Bradley, L.; Carrasco, M.; Coe, D.; Ford, H.; Kelson, D.; Koekemoer, A. M.; Medezinski, E.; Moustakas, J.; Moustakas, L. A.; Nonino, M.; Postman, M.; Rosati, P.; Seidel, G.; Seitz, S.; Sendra, I.; Shu, X.; Vega, J.; Zheng, W.
We perform a strong lensing analysis of the merging galaxy cluster MACS J0416.1-2403 (M0416; z = 0.42) in recent CLASH/HST observations. We identify 70 new multiple images and candidates of 23 background sources in the range 0.7 less than or similar to z(phot) less than or similar to 6.14 including two probable high-redshift dropouts, revealing a highly elongated lens with axis ratio similar or equal to 5:1, and a major axis of similar to 100 '' (z(s) similar to 2). Compared to other well-studied clusters, M0416 shows an enhanced lensing efficiency. Although the critical area is not particularly large (similar or equal to 0.6 square'; z(s) similar to 2), the number of multiple images, per critical area, is anomalously high. We calculate that the observed elongation boosts the number of multiple images, per critical area, by a factor of similar to 2.5x, due to the increased ratio of the caustic area relative to the critical area. Additionally, we find that the observed separation between the two main mass components enlarges the critical area by a factor of similar to 2. These geometrical effects can account for the high number (density) of multiple images observed. We find in numerical simulations that only similar to 4% of the clusters (with M-vir >= 6 x 10(14) h(-1) M-circle dot) exhibit critical curves as elongated as in M0416.
Discovery of a massive X-ray luminous galaxy cluster at z=1.579
(2011) Santos, J. S.; Fassbender, R.; Nastasi, A.; Boehringer, H.; Rosati, P.; Suhada, R.; Pierini, D.; Nonino, M.; Muehlegger, M.; Quintana, H.; Schwope, A. D.; Lamer, G.; de Hoon, A.; Strazzullo, V.
We report on the discovery of a very distant galaxy cluster serendipitously detected in the archive of the XMM-Newton mission, within the scope of the XMM-Newton Distant Cluster Project (XDCP). XMMUJ0044.0-2033 was detected at a high significance level (5 sigma) as a compact, but significantly extended source in the X-ray data, with a soft-band flux f(r < 40 '') = (1.5 +/- 0.3) x 10(-14) erg s(-1) cm(2). Optical/NIR follow-up observations confirmed the presence of an overdensity of red galaxies matching the X-ray emission. The cluster was spectroscopically confirmed to be at z = 1.579 using ground-based VLT/FORS2 spectroscopy. The analysis of the I-H colour-magnitude diagram shows a sequence of red galaxies with a colour range [3.7 < I-H < 4.6] within 1' from the cluster X-ray emission peak. However, the three spectroscopic members (all with complex morphology) have significantly bluer colours relative to the observed red-sequence. In addition, two of the three cluster members have [OII] emission, indicative of on-going star formation. Using the spectroscopic redshift we estimated the X-ray bolometric luminosity, L-bol,L-40 '' similar to 5.8 x 10(44) erg s(-1), implying a massive galaxy cluster. This places XMMU J0044.0-2033 at the forefront of massive distant clusters, closing the gap between lower redshift systems and recently discovered proto-and low-mass clusters at z > 1.6.
Discovery of a very bright strongly lensed galaxy candidate at z ≈ 7.6
(2008) Bradley, L. D.; Bouwens, R. J.; Ford, H. C.; Illingworth, G. D.; Jee, M. J.; Benitez, N.; Broadhurst, T. J.; Franx, M.; Frye, B. L.; Infante, L.; Motta, V.; Rosati, P.; White, R. L.; Zheng, W.
Using Hubble Space Telescope (HST) and Spitzer IRAC imaging, we report the discovery of a very bright strongly lensed Lyman break galaxy (LBG) candidate at z similar to 7.6 in the field of the massive galaxy clusterAbell 1689 (z = 0.18). The galaxy candidate, which we refer to as A1689-zD1, shows a strong z(850) - J(110) break of at least 2.2 mag and is completely undetected (< 1 sigma) in HST Advanced Camera for Surveys (ACS) g(475), r(625), i(775), and z(850) data. These properties, combined with the very blue J(110) - H(160) and H(160) - [4.5 mu m] colors, are exactly the properties of an z similar to 7.6 LBG, and can only be reasonably fit by a star- forming galaxy at z = 7.6 +/- 0.4 (chi(2)(nu) = 1.1). Attempts to reproduce these properties with a model galaxy at z < 4 yield particularly poor fits (chi(2)(nu) >= 25). . A1689- zD1 has an observed (lensed) magnitude of 24.7 AB (8 sigma) in the NICMOS H(160) band and is similar to 1.3 mag brighter than the brightest known z(850)-dropout galaxy. When corrected for the cluster magnification of similar to 9.3 at z similar to 7.6, the candidate has an intrinsic magnitude of H(160) = 27.1 AB, or about an L(*) galaxy at z similar to 7: 6. The source- plane deprojection shows that the star formation is occurring in compact knots of size less than or similar to 300 pc. The best- fit stellar population synthesis models yield a median redshift of 7.6, stellar masses (1.6-3.9) x 10(9) M(circle dot), stellar ages 45-320 Myr, star formation rates less than or similar to 7.6M(circle dot) yr(-1), and low reddening with A(V) <= 0.3. These properties are generally similar to those of LBGs found at z similar to 5-6. The inferred stellar ages suggest a formation redshift of z similar to 8-10 (t less than or similar to 0.63 Gyr). A1689-zD1 is the brightest observed, highly reliable z > 7.0 galaxy candidate found to date.
Distant clusters of galaxies in a deep XMM-Newton observation
(2013) Hoon, A. de; Lamer, G.; Schwope, A.; Mühlegger, M.; Fassbender, R.; Böhringer, H.; Lerchster, M.; Nastasi, A.; Šuhada, R.; Rosati, P.; Pierini, D.; Santo, J. S.; Quintana Godoy, Hernán
Distant galaxy clusters in a deep XMM-Newton field within the CFTHLS D4
(2013) de Hoon, A.; Lamer, G.; Schwope, A.; Muehlegger, M.; Fassbender, R.; Boehringer, H.; Lerchster, M.; Nastasi, A.; Suhada, R.; Verdugo, M.; Dietrich, J. P.; Brimioulle, F.; Rosati, P.; Pierini, D.; Santos, J. S.; Quintana, H.; Rabitz, A.; Takey, A.
Aims. The XMM-Newton distant cluster project (XDCP) aims at the identification of a well defined sample of X-ray selected clusters of galaxies at redshifts z >= 0.8. As part of this project, we analyse the deep XMM-Newton exposure covering one of the CFHTLS deep fields to quantify the cluster content. We validate the optical follow-up strategy as well as the X-ray selection function.
Exploring the galaxy cluster-group transition regime at high redshifts Physical properties of two newly detected z > 1 systems
(2011) Suhada, R.; Fassbender, R.; Nastasi, A.; Boehringer, H.; de Hoon, A.; Pierini, D.; Santos, J. S.; Rosati, P.; Muehlegger, M.; Quintana, H.; Schwope, A. D.; Lamer, G.; Kohnert, J.; Pratt, G. W.
Context. Multi-wavelength surveys for clusters of galaxies are opening a window on the elusive high-redshift (z > 1) cluster population. Well controlled statistical samples of distant clusters will enable us to answer questions about their cosmological context, early assembly phases and the thermodynamical evolution of the intracluster medium.
First simultaneous optical/near-infrared imaging of an X-ray selected, high-redshift cluster of galaxies with GROND The galaxy population of XMMU J0338.7+0030 at z=1.1
(2012) Pierini, D.; Suhada, R.; Fassbender, R.; Nastasi, A.; Boehringer, H.; Salvato, M.; Pratt, G. W.; Lerchster, M.; Rosati, P.; Santos, J. S.; de Hoon, A.; Kohnert, J.; Lamer, G.; Mohr, J. J.; Muehlegger, M.; Quintana, H.; Schwope, A.; Biffi, V.; Chon, G.; Giodini, S.; Koppenhoefer, J.; Verdugo, M.; Ziparo, F.; Afonso, P. M. J.; Clemens, C.; Greiner, J.; Kruehler, T.; Yoldas, A. Kuepcue; Olivares E, F.; Rossi, A.; Yoldas, A.
Context. The XMM-Newton Distant Cluster Project is a serendipitous survey for clusters of galaxies at redshifts z >= 0.8 based on deep archival XMM-Newton observations. X-ray sources identified as extended are screened against existing optical all-sky surveys for galaxies, in case of candidate high-z clusters followed up with imaging at 4 m-class telescopes and, ultimately, multi-object spectroscopy at 8 m-class telescopes. Low-significance candidate high-z clusters are followed up with the seven-channel imager GROND (Gamma-Ray Burst Optical and Near-Infrared Detector) that is mounted at a 2 m-class telescope. Its unique capability of simultaneous imaging in the g', r', i', z', J, H, Ks bands enables the use of the photometric redshift technique.
Galaxy population properties of the massive X-ray luminous galaxy cluster XDCP J0044.0-2033 at z=1.58
(2014) Fassbender, R.; Santos, J.; Verdugo, M.; Lidman, C.; Koyama, Y.; Rosati, P.; Pierini, D.; Romeo, A.; Padilla, Nelson; Nastasi, A.
Hubble Space Telescope ACS Multiband Coronagraphic Imaging of the Debris Disk around β Pictoris
(2006) Golimowski, D. A.; Ardila, D. R.; Krist, J. E.; Clampin, M.; Ford, H. C.; Illingworth, G. D.; Bartko, F.; Benitez, N.; Blakeslee, J. P.; Bouwens, R. J.; Bradley, L. D.; Broadhurst, T. J.; Brown, R. A.; Burrows, C. J.; Cheng, E. S.; Cross, N. J. G.; Demarco, R.; Feldman, P. D.; Franx, M.; Goto, T.; Gronwall, C.; Hartig, G. F.; Holden, B. P.; Homeier, N. L.; Infante, L.; Jee, M. J.; Kimble, R. A.; Lesser, M. P.; Martel, A. R.; Mei, S.; Menanteau, F.; Meurer, G. R.; Miley, G. K.; Motta, V.; Postman, M.; Rosati, P.; Sirianni, M.; Sparks, W. B.; Tran, H. D.; Tsvetanov, Z. I.; White, R. L.; Zheng, W.; Zirm, A. W.
We present F435W(B), F606W (broad V), and F814W(broad I) coronagraphic images of the debris disk around beta Pictoris obtained with the Hubble Space Telescope's Advanced Camera for Surveys. These images provide the most photometrically accurate and morphologically detailed views of the disk between 30 and 300 AU from the star ever recorded in scattered light. We confirm that the previously reported warp in the inner disk is a distinct secondary disk inclined by similar to 5 degrees from the main disk. The projected spine of the secondary disk coincides with the isophotal inflections, or "butterfly asymmetry,'' previously seen at large distances from the star. We also confirm that the opposing extensions of the main disk have different position angles, but we find that this "wing-tilt asymmetry'' is centered on the star rather than offset from it, as previously reported. The main disk's northeast extension is linear from 80 to 250 AU, but the southwest extension is distinctly bowed with an amplitude of similar to 1 AU over the same region. Both extensions of the secondary disk appear linear, but not collinear, from 80 to 150 AU. Within similar to 120 AU of the star, the main disk is similar to 50% thinner than previously reported. The surface brightness profiles along the spine of the main disk are fitted with four distinct radial power laws between 40 and 250 AU, while those of the secondary disk between 80 and 150 AU are fitted with single power laws. These discrepancies suggest that the two disks have different grain compositions or size distributions. The F606W/F435W and F814W/F435W flux ratios of the composite disk are nonuniform and asymmetric about both projected axes of the disk. The disk's northwest region appears 20%-30% redder than its southeast region, which is inconsistent with the notion that forward scattering from the nearer northwest side of the disk should diminish with increasing wavelength. Within similar to 120 AU, the m(F435W)-m(F606W) and m(F435W)-m(F814W) colors along the spine of the main disk are similar to 10% and similar to 20% redder, respectively, than those of beta Pic. These colors increasingly redden beyond similar to 120 AU, becoming 25% and 40% redder, respectively, than the star at 250 AU. These measurements overrule previous determinations that the disk is composed of neutrally scattering grains. The change in color gradient at similar to 120 AU nearly coincides with the prominent inflection in the surface brightness profile at similar to 115 AU and the expected water-ice sublimation boundary. We compare the observed red colors within similar to 120 AU with the simulated colors of nonicy grains having a radial number density alpha r(-3) and different compositions, porosities, and minimum grain sizes. The observed colors are consistent with those of compact or moderately porous grains of astronomical silicate and/or graphite with sizes greater than or similar to 0.15-0.20 mu m, but the colors are inconsistent with the blue colors expected from grains with porosities greater than or similar to 90%. The increasingly red colors beyond the ice sublimation zone may indicate the condensation of icy mantles on the refractory grains, or they may reflect an increasing minimum grain size caused by the cessation of cometary activity.
Kinematic analysis of a sample of X-ray luminous distant galaxy clusters The L_x-σ_v relation in the z > 0.6 universe
(2014) Nastasi, A.; Boehringer, H.; Fassbender, R.; De Hoon, A.; Lamer, G.; Mohr, J. J.; Padilla, N.; Pratt, G. W.; Quintana, H.; Rosati, P.; Santos, J. S.; Schwope, A. D.; Suhada, R.; Verdugo, M.
Aims. Observations and cosmological simulations show galaxy clusters as a family of nearly self-similar objects with properties that can be described by scaling relations as a function of mass and time. Here we study the scaling relations between the galaxy velocity dispersion (sigma(v)) and X-ray quantities, such as X-ray bolometric luminosity (L-X,500(Bol)) and temperature (T-X) in galaxy clusters at high redshifts (0.64 <= z <= 1.46). We also compare our results with the analogous study of the local HIFLUGCS sample.
Latin American Registry of Pediatric Renal Transplantation 2004-2008
(2010) Goulart, P.; Koch, P.; Medina-Pestana, J.; Garcia, C.; Bittencourt, V.; Medeiros, M.; Munoz, R.; Delucchi, A.; Lillo, A. M.; Ariza, M.; Bosque, M.; Carvalho, D.; Matuck, T.; Meneses, R.; Fontes, J.; Monteiro, D. C.; Neto, E. Davi; Pinto, V.; Salas, P.; Prates, L.; Belanguero, V.; Pereira, L.; Lima, E.; Penido, J. M.; Benini, V.; Laranjo, S.; Silva, J. M.; Orta, N.; Coronel, V.; Cisneros, A.; Arriaga, J.; Sebastian, M. J.; Abbud-Filho, M.; Fernandez, I.; Gastelbondo, R.; Medjia, N.; Rosati, P.; Hevia, P.; Baptista, M. A.; Ramalho, H.; Diaz, M.; Monteverde, M.; Ferraris, J.; Repetto, H.; Exeni, R.; Florentin, L.; Florin, J.; Cazorla, N.; Casadei, D.; Melendez, K.; Calderon, R.; Silva, V.; Patino, J.; Palacio, D.; Madrigal, G.; Sandoval, M.; Urbina, C.; Loza, R.; Cavagnaro, F.; Vogel, A.; Jimenez, W.; Lou, R.; Rodriguez, C.; Aguilar, C.; Galvez, H.; Rodriguez, L.; Paladini, J.; Agusti, J.; Puelma, F.; Troche, A.; Martinez-Pico, M.; Higueras, W.; Liendo, C.; Restrepo, J.; Caicedo, L. A.; Socorro, F.; Semprum, P.
The Latin American Pediatric Nephrology Association (ALANEPE) reports the first regional kidney transplant registry in Latin America. A mean range of 75%, 30% to 100% renal transplant recipients under 21 yr old were included. Out of 20 countries invited to participate, 14 performed renal transplant, 11 had universal financial support from their governments. The centers included: Brazil (9), Argentina (4), Chile (4), Venezuela (3), Mexico (2), and one in: Cuba, Colombia, Costa Rica, Nicaragua, Guatemala, Ecuador, Honduras, Paraguay and Peru. The registry included 1458 patients, average of 291 per year, 55% male. Mean follow-up 23.4 +/- 17 months; mean age was 11.7 +/- 4.3 yr (1-21), 11% under five yr of age. Etiology: uropathy/ reflux nephropathy 27%, glomerulopathies 24% (included 12% FSGS), hypo/dysplasia (11%), vascular (6%), congenital/hereditary (5%), unknown (19%). Induction therapy: 71% anti-IL2RAb, 13% ATG/TIMO, 14% non-induction. Maintenance therapy: Tacrolimus 64%, Cyclosporine 32%, MMF 54%, MPS 20%, noTORi 96%, steroids 90%, withdrawal or steroid avoidance 10%. Loss of graft 155/1458 (11%), death with functioning graft (3.4%), vascular thrombosis (2.8%), acute rejection (2.8%), recurrence of disease (1%). Forty-eight patients died (3.3%); infection was the main cause 23 (2.1%). Global patient survival rate at one, three, and five yr was 97%, 96%, and 96%. Graft survival rate at one, three, and five yr LRD was 96%, 93% and 89%; for DD 92%, 86% and 76% respectively. Both survival rates were higher in LRD (p < 0.008 and p < 0.001). A pediatric renal transplant study has started, making information available to be shared between the centers and the world.
New multiple AGN systems with subarcsec separation: Confirmation of candidates selected via the novel GMP method
(2023) Ciurlo, A.; Mannucci, F.; Yeh, S.; Amiri, A.; Carniani, S.; Cicone, C.; Cresci, G.; Lusso, E.; Marasco, A.; Marconcini, C.; Marconi, A.; Nardini, E.; Pancino, E.; Rosati, P.; Rubinur, K.; Severgnini, P.; Scialpi, M.; Tozzi, G.; Venturi, G.; Vignali, C.; Volonteri, M.
The existence of multiple active galactic nuclei (AGNs) at small projected distances on the sky is due to either the presence of multiple, inspiraling supermassive black holes, or to gravitational lensing of a single AGN. Both phenomena allow us to address important astrophysical and cosmological questions. However, few kiloparsec-separation multiple AGNs are currently known. Recently, the newly developed Gaia multi-peak (GMP) method provided numerous new candidate members of these populations. We present spatially resolved, integral-field spectroscopy of a sample of four GMP-selected multiple AGN candidates. In all of these systems, we detect two or more components with subarcsec separations. We find that two of the systems are dual AGNs, one is either an intrinsic triple or a lensed dual AGN, while the last system is a chance alignment of an AGN and a star. Our observations double the number of confirmed multiple AGNs at projected separations below 7 kpc at z > 0.5, present the first detection of a possible triple AGN in a single galaxy at z > 0.5, and successfully test the GMP method as a novel technique to discover previously unknown multiple AGNs.
Scaling Relations and Overabundance of Massive Clusters at z ≳ 1 from Weak-lensing Studies with the Hubble Space Telescope
(2011) Jee, M. J.; Dawson, K. S.; Hoekstra, H.; Perlmutter, S.; Rosati, P.; Brodwin, M.; Suzuki, N.; Koester, B.; Postman, M.; Lubin, L.; Meyers, J.; Stanford, S. A.; Barbary, K.; Barrientos, F.; Eisenhardt, P.; Ford, H. C.; Gilbank, D. G.; Gladders, M. D.; Gonzalez, A.; Harris, D. W.; Huang, X.; Lidman, C.; Rykoff, E. S.; Rubin, D.; Spadafora, A. L.
We present weak gravitational lensing analysis of 22 high-redshift (z greater than or similar to 1) clusters based on Hubble Space Telescope images. Most clusters in our sample provide significant lensing signals and are well detected in their reconstructed two-dimensional mass maps. Combining the current results and our previous weak-lensing studies of five other high-z clusters, we compare gravitational lensing masses of these clusters with other observables. We revisit the question whether the presence of the most massive clusters in our sample is in tension with the current. CDM structure formation paradigm. We find that the lensing masses are tightly correlated with the gas temperatures and establish, for the first time, the lensing mass-temperature relation at z greater than or similar to 1. For the power-law slope of the M-T-X relation (M proportional to T-alpha), we obtain alpha = 1.54 +/- 0.23. This is consistent with the theoretical self-similar prediction alpha = 3/2 and with the results previously reported in the literature for much lower redshift samples. However, our normalization is lower than the previous results by 20%-30%, indicating that the normalization in the M-T-X relation might evolve. After correcting for Eddington bias and updating the discovery area with a more conservative choice, we find that the existence of the most massive clusters in our sample still provides a tension with the current. CDM model. The combined probability of finding the four most massive clusters in this sample after the marginalization over cosmological parameters is less than 1%.
THE CLUSTER LENSING AND SUPERNOVA SURVEY WITH HUBBLE (CLASH): STRONG-LENSING ANALYSIS OF A383 FROM 16-BAND HST/WFC3/ACS IMAGING
(2011) Zitrin, A.; Broadhurst, T.; Coe, D.; Umetsu, K.; Postman, M.; Benitez, N.; Meneghetti, M.; Medezinski, E.; Jouvel, S.; Bradley, L.; Koekemoer, A.; Zheng, W.; Ford, H.; Merten, J.; Kelson, D.; Lahav, O.; Lemze, D.; Molino, A.; Nonino, M.; Donahue, M.; Rosati, P.; Van der Wel, A.; Bartelmann, M.; Bouwens, R.; Graur, O.; Graves, G.; Host, O.; Infante, L.; Jha, S.; Jimenez-Teja, Y.; Lazkoz, R.; Maoz, D.; McCully, C.; Melchior, P.; Moustakas, L. A.; Ogaz, S.; Patel, B.; Regoes, E.; Riess, A.; Rodney, S.; Seitz, S.
We examine the inner mass distribution of the relaxed galaxy cluster A383 (z = 0.189), in deep 16 band Hubble Space Telescope/ACS+WFC3 imaging taken as part of the Cluster Lensing And Supernova survey with Hubble (CLASH) multi-cycle treasury program. Our program is designed to study the dark matter distribution in 25 massive clusters, and balances depth with a wide wavelength coverage, 2000-16000 angstrom, to better identify lensed systems and generate precise photometric redshifts. This photometric information together with the predictive strength of our strong-lensing analysis method identifies 13 new multiply lensed images and candidates, so that a total of 27 multiple images of nine systems are used to tightly constrain the inner mass profile gradient, d log Sigma/d log r similar or equal to -0.6 +/- 0.1 (r < 160 kpc). We find consistency with the standard distance-redshift relation for the full range spanned by the lensed images, 1.01 < z < 6.03, with the higher-redshift sources deflected through larger angles as expected. The inner mass profile derived here is consistent with the results of our independent weak-lensing analysis of wide-field Subaru images, with good agreement in the region of overlap (similar to 0.7-1 arcmin). Combining weak and strong lensing, the overall mass profile is well fitted by a Navarro-Frenk-White profile with M-vir = (5.37(-0.63)(+0.70) +/- 0.26) x 10(14) M-circle dot h(-1) and a relatively high concentration, c(vir) = 8.77(-0.42)(+0.44) +/- 0.23, which lies above the standard c-M relation similar to other well-studied clusters. The critical radius of A383 is modest by the standards of other lensing clusters, r(E) similar or equal to 16 +/- 2 '' (for z(s) = 2.55), so the relatively large number of lensed images uncovered here with precise photometric redshifts validates our imaging strategy for the CLASH survey. In total we aim to provide similarly high-quality lensing data for 25 clusters, 20 of which are X-ray-selected relaxed clusters, enabling a precise determination of the representative mass profile free from lensing bias.
The Extended Chandra Deep Field-South Survey: Optical Spectroscopy of Faint X-ray Sources with the VLT and Keck
(2006) Silverman, J. D.; Treister, Ezequiel; Mainieri, V.; Salvato, M.; Hasinger, G.; Bergeron, J.; Capak, P.; Szokoly, G.; Finoguenov, A.; Gilli, R.; Rosati, P.

Browsing by Author "Rosati, P."

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