21 results on '"Lemze, Doron"'
Search Results
2. Erratum: Single-cell spatial reconstruction reveals global division of labour in the mammalian liver
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Halpern, Keren Bahar, Shenhav, Rom, Matcovitch-Natan, Orit, Tóth, Beáta, Lemze, Doron, Golan, Matan, Massasa, Efi E., Baydatch, Shaked, Landen, Shanie, Moor, Andreas E., Brandis, Alexander, Giladi, Amir, Stokar-Avihail, Avigail, David, Eyal, Amit, Ido, and Itzkovitz, Shalev
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- 2017
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3. Single-cell spatial reconstruction reveals global division of labour in the mammalian liver
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Halpern, Keren Bahar, Shenhav, Rom, Matcovitch-Natan, Orit, Tóth, Beáta, Lemze, Doron, Golan, Matan, Massasa, Efi E., Baydatch, Shaked, Landen, Shanie, Moor, Andreas E., Brandis, Alexander, Giladi, Amir, Stokar-Avihail, Avigail, David, Eyal, Amit, Ido, and Itzkovitz, Shalev
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- 2017
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4. A magnified young galaxy from about 500 million years after the Big Bang
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Zheng, Wei, Postman, Marc, Zitrin, Adi, Moustakas, John, Shu, Xinwen, Jouvel, Stephanie, Høst, Ole, Molino, Alberto, Bradley, Larry, Coe, Dan, Moustakas, Leonidas A., Carrasco, Mauricio, Ford, Holland, Benítez, Narciso, Lauer, Tod R., Seitz, Stella, Bouwens, Rychard, Koekemoer, Anton, Medezinski, Elinor, Bartelmann, Matthias, Broadhurst, Tom, Donahue, Megan, Grillo, Claudio, Infante, Leopoldo, Jha, Saurabh W., Kelson, Daniel D., Lahav, Ofer, Lemze, Doron, Melchior, Peter, Meneghetti, Massimo, Merten, Julian, Nonino, Mario, Ogaz, Sara, Rosati, Piero, Umetsu, Keiichi, and van der Wel, Arjen
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- 2012
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5. Nuclear Retention of mRNA in Mammalian Tissues.
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Bahar Halpern, Keren, Caspi, Inbal, Lemze, Doron, Levy, Maayan, Landen, Shanie, Elinav, Eran, Ulitsky, Igor, and Itzkovitz, Shalev
- Abstract
Summary mRNA is thought to predominantly reside in the cytoplasm, where it is translated and eventually degraded. Although nuclear retention of mRNA has a regulatory potential, it is considered extremely rare in mammals. Here, to explore the extent of mRNA retention in metabolic tissues, we combine deep sequencing of nuclear and cytoplasmic RNA fractions with single-molecule transcript imaging in mouse beta cells, liver, and gut. We identify a wide range of protein-coding genes for which the levels of spliced polyadenylated mRNA are higher in the nucleus than in the cytoplasm. These include genes such as the transcription factor ChREBP, Nlrp6, Glucokinase, and Glucagon receptor. We demonstrate that nuclear retention of mRNA can efficiently buffer cytoplasmic transcript levels from noise that emanates from transcriptional bursts. Our study challenges the view that transcripts predominantly reside in the cytoplasm and reveals a role of the nucleus in dampening gene expression noise. [ABSTRACT FROM AUTHOR]
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- 2015
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6. CLASH: COMPLETE LENSING ANALYSIS OF THE LARGEST COSMIC LENS MACS J0717.5+3745 AND SURROUNDING STRUCTURES.
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Medezinski, Elinor, Umetsu, Keiichi, Nonino, Mario, Merten, Julian, Zitrin, Adi, Broadhurst, Tom, Donahue, Megan, Sayers, Jack, Waizmann, Jean-Claude, Koekemoer, Anton, Coe, Dan, Molino, Alberto, Melchior, Peter, Mroczkowski, Tony, Czakon, Nicole, Postman, Marc, Meneghetti, Massimo, Lemze, Doron, Ford, Holland, and Grillo, Claudio
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GALAXY clusters ,GRAVITATIONAL lenses ,ACCRETION (Astrophysics) ,SUPERNOVAE ,ASTROPHYSICS research - Abstract
The galaxy cluster MACS J0717.5+3745 (z = 0.55) is the largest known cosmic lens, with complex internal structures seen in deep X-ray, Sunyaev-Zel'dovich effect, and dynamical observations. We perform a combined weak- and strong-lensing analysis with wide-field BVR
c i′z′ Subaru/Suprime-Cam observations and 16-band Hubble Space Telescope observations taken as part of the Cluster Lensing And Supernova survey with Hubble. We find consistent weak distortion and magnification measurements of background galaxies and combine these signals to construct an optimally estimated radial mass profile of the cluster and its surrounding large-scale structure out to 5 Mpc h–1 . We find consistency between strong-lensing and weak-lensing in the region where these independent data overlap, <500 kpc h–1 . The two-dimensional weak-lensing map reveals a clear filamentary structure traced by distinct mass halos. We model the lensing shear field with nine halos, including the main cluster, corresponding to mass peaks detected above 2.5σκ . The total mass of the cluster as determined by the different methods is Mvir ≈ (2.8 ± 0.4) × 1015 M☼ . Although this is the most massive cluster known at z > 0.5, in terms of extreme value statistics, we conclude that the mass of MACS J0717.5+3745 by itself is not in serious tension with ΛCDM, representing only a ∼2σ departure above the maximum simulated halo mass at this redshift. [ABSTRACT FROM AUTHOR]- Published
- 2013
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7. THE CONTRIBUTION OF HALOS WITH DIFFERENT MASS RATIOS TO THE OVERALL GROWTH OF CLUSTER-SIZED HALOS.
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Lemze, Doron, Postman, Marc, Genel, Shy, Ford, Holland C., Balestra, Italo, Donahue, Megan, Kelson, Daniel, Nonino, Mario, Mercurio, Amata, Biviano, Andrea, Rosati, Piero, Umetsu, Keiichi, Sand, David, Koekemoer, Anton, Meneghetti, Massimo, Melchior, Peter, Newman, Andrew B., Bhatti, Waqas A., Voit, G. Mark, and Medezinski, Elinor
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GALACTIC halos , *ASTROPHYSICS research , *DARK matter , *INTERSTELLAR medium , *GALAXIES - Abstract
We provide a new observational test for a key prediction of the ΛCDM cosmological model: the contributions of mergers with different halo-to-main-cluster mass ratios to cluster-sized halo growth. We perform this test by dynamically analyzing 7 galaxy clusters, spanning the redshift range 0.13 < zc < 0.45 and caustic mass range 0.4-1.5 M☼, with an average of 293 spectroscopically confirmed bound galaxies to each cluster. The large radial coverage (a few virial radii), which covers the whole infall region, with a high number of spectroscopically identified galaxies enables this new study. For each cluster, we identify bound galaxies. Out of these galaxies, we identify infalling and accreted halos and estimate their masses and their dynamical states. Using the estimated masses, we derive the contribution of different mass ratios to cluster-sized halo growth. For mass ratios between ∼0.2 and ∼0.7, we find a ∼1σ agreement with ΛCDM expectations based on the Millennium simulations I and II. At low mass ratios, ≲ 0.2, our derived contribution is underestimated since the detection efficiency decreases at low masses, ∼2 × 1014M☼. At large mass ratios, ≳ 0.7, we do not detect halos probably because our sample, which was chosen to be quite X-ray relaxed, is biased against large mass ratios. Therefore, at large mass ratios, the derived contribution is also underestimated. [ABSTRACT FROM AUTHOR]
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- 2013
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8. GALAXY HALO TRUNCATION AND GIANT ARC SURFACE BRIGHTNESS RECONSTRUCTION IN THE CLUSTER MACSJ1206.2-0847.
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EICHNER, THOMAS, SEITZ, STELLA, SUYU, SHERRY H., HALKOLA, ALEKSI, UMETSU, KEIICHI, ZITRIN, ADI, COE, DAN, MONNA, ANNA, ROSATI, PIERO, GRILLO, CLAUDIO, BALESTRA, ITALO, POSTMAN, MARC, KOEKEMOER, ANTON, WEI ZHENG, HØST, OLE, LEMZE, DORON, BROADHURST, TOM, MOUSTAKAS, LEONIDAS, BRADLEY, LARRY, and MOLINO, ALBERTO
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GALAXIES ,X-ray emission spectroscopy ,STAR clusters ,SURFACE brightness (Astronomy) ,GRAVITATIONAL lenses - Abstract
In this work, we analyze the mass distribution of MACSJ1206.2-0847, particularly focusing on the halo properties of its cluster members. The cluster appears relaxed in its X-ray emission, but has a significant amount of intracluster light that is not centrally concentrated, suggesting that galaxy-scale interactions are still ongoing despite the overall relaxed state. The cluster lenses 12 background galaxies into multiple images and one galaxy at z = 1.033 into a giant arc and its counterimage. The multiple image positions and the surface brightness (SFB) distribution of the arc, which is bent around several cluster members, are sensitive to the cluster galaxy halo properties. We model the cluster mass distribution with a Navarro-Frenk-White profile and the galaxy halos with two parameters for the mass normalization and the extent of a reference halo assuming scalings with their observed near-infrared light. We match the multiple image positions at an rms level of 0. ''85 and can reconstruct the SFB distribution of the arc in several filters to a remarkable accuracy based on this cluster model. The length scale where the enclosed galaxy halo mass is best constrained is about 5 effective radii-a scale in between those accessible to dynamical and field strong-lensing mass estimates on the one hand and galaxy-galaxy weak-lensing results on the other hand. The velocity dispersion and halo size of a galaxy with m160W,AB = 19.2 and M
B,Vega = -20.7 are σ = 150 km s-1 and r ≈ 26±6 kpc, respectively, indicating that the halos of the cluster galaxies are tidally stripped.We also reconstruct the unlensed source, which is smaller by a factor of ~5.8 in area, demonstrating the increase in morphological information due to lensing. We conclude that this galaxy likely has star-forming spiral arms with a red (older) central component. [ABSTRACT FROM AUTHOR]- Published
- 2013
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9. Cluster contribution to the X-ray background as a cosmological probe.
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Lemze, Doron, Sadeh, Sharon, and Rephaeli, Yoel
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GALAXY clusters , *X-ray spectroscopy , *METAPHYSICAL cosmology , *DARK matter , *INTERSTELLAR medium , *ASTRONOMY - Abstract
Extensive measurements of the X-ray background (XRB) yield a reasonably reliable characterization of its basic properties. Having resolved most of the cosmic XRB into discrete sources, the levels and spectral shapes of its main components can be used to probe both the source populations and also alternative cosmological and large-scale structure models. Recent observations of clusters seem to provide evidence that clusters formed earlier and are more abundant than predicted in the standard Λ cold dark matter (ΛCDM) model. This motivates interest in alternative models that predict enhanced power on cluster scales. We calculate predicted levels and spectra of the superposed emission from groups and clusters of galaxies in ΛCDM and in two viable alternative non-Gaussian and early dark energy models. The predicted levels of the contribution of clusters to the XRB in the non-Gaussian models exceed the measured level at low energies and levels of the residual XRB in the 2–8 keV band; these particular models are essentially ruled out. Our work demonstrates the diagnostic value of the integrated X-ray emission from clusters, by considering also its dependences on different metallicities, gas and temperature profiles, Galactic absorption, merger scenarios and on a non-thermal pressure component. We also show that the XRB can be used for an upper limit for the concentration parameter value. [ABSTRACT FROM AUTHOR]
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- 2009
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10. Mass and gas profiles in A1689: joint X-ray and lensing analysis.
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Lemze, Doron, Barkana, Rennan, Broadhurst, Tom J., and Rephaeli, Yoel
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X-rays , *LENSES , *COAL gas , *MASS (Physics) , *TEMPERATURE , *ENTROPY , *CLUSTER analysis (Statistics) - Abstract
We carry out a comprehensive joint analysis of high-quality HST/ACS and Chandra measurements of A1689, from which we derive mass, temperature, X-ray emission and abundance profiles. The X-ray emission is smooth and symmetric, and the lensing mass is centrally concentrated indicating a relaxed cluster. Assuming hydrostatic equilibrium we deduce a 3D mass profile that agrees simultaneously with both the lensing and X-ray measurements. However, the projected temperature profile predicted with this 3D mass profile exceeds the observed temperature by ∼30 per cent at all radii, a level of discrepancy comparable to the level found for other relaxed clusters. This result may support recent suggestions from hydrodynamical simulations that denser, more X-ray luminous small-scale structure can bias observed temperature measurements downward at about the same (∼30 per cent) level. We determine the gas entropy at (where rvir is the virial radius) to be ∼800 keV cm2, as expected for a high-temperature cluster, but its profile at has a power-law form with index ∼0.8, considerably shallower than the ∼1.1 index advocated by theoretical studies and simulations. Moreover, if a constant entropy ‘floor’ exists at all, then it is within a small region in the inner core, , in accord with previous theoretical studies of massive clusters. [ABSTRACT FROM AUTHOR]
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- 2008
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11. DYNAMICAL STUDY OF A1689 FROM WIDE-FIELD VLT/VIMOS SPECTROSCOPY: MASS PROFILE, CONCENTRATION PARAMETER, AND VELOCITY ANISOTROPY
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Lemze, Doron, Broadhurst, Tom, Rephaeli, Yoel, Barkana, Rennan, and Umetsu, Keiichi
- Abstract
We examine the dynamics structure of the rich cluster A1689, combining VLT/VIMOS spectroscopy with Subaru/Suprime-Cam imaging. The radial velocity distribution of [?]500 cluster members is bounded by a pair of clearly defined velocity caustics, with a maximum amplitude of [?]|4000| km s-1 at [?] 300 h -1 kpc, beyond which the amplitude steadily declines, approaching zero velocity at a limiting radius of [?]2 h -1 Mpc. We derive the three-dimensional velocity anisotropy and galaxy number density profiles using a model-independent method to solve the Jeans equation, simultaneously incorporating the observed velocity dispersion profile, the galaxy counts from deep Subaru imaging, and our previously derived cluster mass profile from a joint lensing and X-ray analysis. The velocity anisotropy is found to be predominantly radial at large radius, becoming increasingly tangential towards the center, in accord with expectations. We also analyze the galaxy data independently of our previous analysis using two different methods: The first is based on a solution of the Jeans equation assuming an Navarro-Frenk-White (NFW) form for the mass distribution, whereas in the second method the caustic amplitude is used to determine the escape velocity. The cluster virial mass derived by both of these dynamical methods is in good agreement with results from our earlier lensing and X-ray analysis. We also confirm the high NFW concentration parameter, with results from both methods combined to yield c vir > 13 (1s). The inferred virial radius is consistent with the limiting radius where the caustics approach zero velocity and where the counts of cluster members drop off, suggesting that infall onto A1689 is currently not significant.
- Published
- 2009
12. MASS AND HOT BARYONS IN MASSIVE GALAXY CLUSTERS FROM SUBARU WEAK-LENSING AND AMiBA SUNYAEV-ZEL'DOVICH EFFECT OBSERVATIONS
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Umetsu, Keiichi, Birkinshaw, Mark, Liu, Chin, Proty, Huei, Medezinski, Elinor, Broadhurst, Tom, Lemze, Doron, Zitrin, Adi, P, Paul T., Locutus, Wei, Koch, Patrick M., Liao, Wei, Lin, Yang, Molnar, Sandor M., Nishioka, Hiroaki, Wang, Cheng, Altamirano, Pablo, Chang, Hao, Chang, Hao, Chang, Wei, Chen, Tang, Han, Chiang, Huang, De, Hwang, Jing, Jiang, Homin, Kesteven, Michael, Kubo, Derek Y., Li, Te, Martin, Pierre, Oshiro, Peter, Raffin, Philippe, Wei, Tashun, and Wilson, Warwick
- Abstract
We present a multiwavelength analysis of a sample of four hot (TX > 8 keV) X-ray galaxy clusters (A1689, A2261, A2142, and A2390) using joint AMiBA Sunyaev-Zel'dovich effect (SZE) and Subaru weak-lensing observations, combined with published X-ray temperatures, to examine the distribution of mass and the intracluster medium (ICM) in massive cluster environments. Our observations show that A2261 is very similar to A1689 in terms of lensing properties. Many tangential arcs are visible around A2261, with an effective Einstein radius [?]40'' (at z [?] 1.5), which when combined with our weak-lensing measurements implies a mass profile well fitted by a Navarro-Frenk-White model with a high concentration c vir [?] 10, similar to A1689 and to other massive clusters. The cluster A2142 shows complex mass substructure, and displays a shallower profile (c vir [?] 5), consistent with detailed X-ray observations which imply recent interaction. The AMiBA map of A2142 exhibits an SZE feature associated with mass substructure lying ahead of the sharp northwest edge of the X-ray core suggesting a pressure increase in the ICM. For A2390 we obtain highly elliptical mass and ICM distributions at all radii, consistent with other X-ray and strong-lensing work. Our cluster gas fraction measurements, free from the hydrostatic equilibrium assumption, are overall in good agreement with published X-ray and SZE observations, with the sample-averaged gas fraction of [?]f gas(
- Published
- 2009
13. XMM-Newton Spectroscopy of the Starburst-Dominated Ultraluminous Infrared Galaxy NGC 6240
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Netzer, Hagai, Lemze, Doron, Kaspi, Shai, and Chelouche, Doron
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We present a new XMM-Newton observation of the ultraluminous infrared galaxy (ULIRG) NGC 6240. We analyze the reflecting grating spectrometer (RGS) data, as well as data from the other instruments, and find a starburst-dominated 0.5-3 keV spectrum with global properties resembling those observed in M82 but with a much higher luminosity. We show that the starburst region can be divided into an outer zone, beyond a radius of about 2.1 kpc, with a gas temperature of about 107 K, and a central region with temperatures in the range (2-6) x 107 K. The gas in the outer region emits most of the observed O VIII Lya line, and the gas in the inner region the emission lines of higher ionization ions, including a strong Fe XXV line. We also identify a small inner part, very close to the active nuclei, with typical Seyfert 2 properties, including a large amount of photoionized gas producing a strong Fe Ka 6.4 keV line. The combined abundance, temperature, and emission measure analysis indicates supersolar Ne/O, Mg/O, Si/O, S/O, and possibly also Fe/O. The analysis suggests densities in the range of (0.07-0.28)[?]-1/2 cm-3 and a total thermal gas mass of ~4 x 108[?]1/2 M, where [?] is the volume filling factor. We used a simple model to argue that a massive starburst with an age of [?]2 x 107 yr can explain most of the observed properties of the source. NGC 6240 is perhaps the clearest case of an X-ray-bright luminous AGN that is in a merger and whose soft X-ray spectrum is dominated by a powerful starburst.
- Published
- 2005
14. A conserved abundant cytoplasmic long noncoding RNA modulates repression by Pumilio proteins in human cells.
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Tichon, Ailone, Gil, Noa, Lubelsky, Yoav, Havkin Solomon, Tal, Lemze, Doron, Itzkovitz, Shalev, Stern-Ginossar, Noam, and Ulitsky, Igor
- Published
- 2016
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15. CLASH: EXTREME EMISSION-LINE GALAXIES AND THEIR IMPLICATION ON SELECTION OF HIGH-REDSHIFT GALAXIES.
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Huang, Xingxing, Zheng, Wei, Wang, Junxian, Ford, Holland, Lemze, Doron, Moustakas, John, Shu, Xinwen, Van der Wel, Arjen, Zitrin, Adi, Frye, Brenda L., Postman, Marc, Bartelmann, Matthias, Benítez, Narciso, Bradley, Larry, Broadhurst, Tom, Coe, Dan, Donahue, Megan, Infante, Leopoldo, Kelson, Daniel, and Koekemoer, Anton
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GALAXIES ,REDSHIFT ,PHOTOMETRY ,STELLAR luminosity function ,SIGNAL-to-noise ratio - Abstract
We utilize the Cluster Lensing And Supernova survey with Hubble observations of 25 clusters to search for extreme emission-line galaxies (EELGs). The selections are carried out in two central bands: F105W (Y
105 ) and F125W (J125 ), as the flux of the central bands could be enhanced by the presence of [O III] λλ4959, 5007 at redshifts of ∼0.93-1.14 and 1.57-1.79, respectively. The multiband observations help to constrain the equivalent widths (EWs) of emission lines. Thanks to cluster lensing, we are able to identify 52 candidates down to an intrinsic limiting magnitude of 28.5 and to a rest-frame [O III] λλ4959, 5007 EW of ≃ 3700 Å. Our samples include a number of EELGs at lower luminosities that are missed in other surveys, and the extremely high EW can only be found in such faint galaxies. These EELGs can mimic a dropout feature similar to that of high-redshift galaxies and contaminate the color-color selection of high-redshift galaxies when the signal-to-noise ratio is limited or the band coverage is incomplete. [ABSTRACT FROM AUTHOR]- Published
- 2015
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16. CLASH: WEAK-LENSING SHEAR-AND-MAGNIFICATION ANALYSIS OF 20 GALAXY CLUSTERS.
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Umetsu, Keiichi, Medezinski, Elinor, Nonino, Mario, Merten, Julian, Postman, Marc, Meneghetti, Massimo, Donahue, Megan, Czakon, Nicole, Molino, Alberto, Seitz, Stella, Gruen, Daniel, Lemze, Doron, Balestra, Italo, Benítez, Narciso, Biviano, Andrea, Broadhurst, Tom, Ford, Holland, Grillo, Claudio, Koekemoer, Anton, and Melchior, Peter
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DARK matter ,OPEN clusters of stars ,METAPHYSICAL cosmology ,STAR clusters ,GRAVITATIONAL lenses - Abstract
We present a joint shear-and-magnification weak-lensing analysis of a sample of 16 X-ray-regular and 4 high-magnification galaxy clusters at 0.19 ≲ z ≲ 0.69 selected from the Cluster Lensing And Supernova survey with Hubble (CLASH). Our analysis uses wide-field multi-color imaging, taken primarily with Suprime-Cam on the Subaru Telescope. From a stacked-shear-only analysis of the X-ray-selected subsample, we detect the ensemble-averaged lensing signal with a total signal-to-noise ratio of ≃ 25 in the radial range of 200-3500 kpc h
–1 , providing integrated constraints on the halo profile shape and concentration-mass relation. The stacked tangential-shear signal is well described by a family of standard density profiles predicted for dark-matter-dominated halos in gravitational equilibrium, namely, the Navarro-Frenk-White (NFW), truncated variants of NFW, and Einasto models. For the NFW model, we measure a mean concentration of at an effective halo mass of . We show that this is in excellent agreement with Λ cold dark matter (ΛCDM) predictions when the CLASH X-ray selection function and projection effects are taken into account. The best-fit Einasto shape parameter is , which is consistent with the NFW-equivalent Einasto parameter of ∼0.18. We reconstruct projected mass density profiles of all CLASH clusters from a joint likelihood analysis of shear-and-magnification data and measure cluster masses at several characteristic radii assuming an NFW density profile. We also derive an ensemble-averaged total projected mass profile of the X-ray-selected subsample by stacking their individual mass profiles. The stacked total mass profile, constrained by the shear+magnification data, is shown to be consistent with our shear-based halo-model predictions, including the effects of surrounding large-scale structure as a two-halo term, establishing further consistency in the context of the ΛCDM model. [ABSTRACT FROM AUTHOR]- Published
- 2014
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17. CLASH-VLT: CONSTRAINTS ON THE DARK MATTER EQUATION OF STATE FROM ACCURATE MEASUREMENTS OF GALAXY CLUSTER MASS PROFILES.
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Sartoris, Barbara, Biviano, Andrea, Rosati, Piero, Borgani, Stefano, Umetsu, Keiichi, Bartelmann, Matthias, Girardi, Marisa, Grillo, Claudio, Lemze, Doron, Zitrin, Adi, Balestra, Italo, Mercurio, Amata, Nonino, Mario, Postman, Marc, Czakon, Nicole, Bradley, Larry, Broadhurst, Tom, Coe, Dan, Medezinski, Elinor, and Melchior, Peter
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- 2014
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18. CLASH: PRECISE NEW CONSTRAINTS ON THE MASS PROFILE OF THE GALAXY CLUSTER A2261.
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Coe, Dan, Umetsu, Keiichi, Zitrin, Adi, Donahue, Megan, Medezinski, Elinor, Postman, Marc, Carrasco, Mauricio, Anguita, Timo, Geller, Margaret J., Rines, Kenneth J., Diaferio, Antonaldo, Kurtz, Michael J., Bradley, Larry, Koekemoer, Anton, Zheng, Wei, Nonino, Mario, Molino, Alberto, Mahdavi, Andisheh, Lemze, Doron, and Infante, Leopoldo
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GALAXY clusters ,STELLAR mass ,DARK matter ,DARK energy ,ASTRONOMICAL photometry - Abstract
We precisely constrain the inner mass profile of A2261 (z = 0.225) for the first time and determine that this cluster is not “overconcentrated” as found previously, implying a formation time in agreement with ΛCDM expectations. These results are based on multiple strong-lensing analyses of new 16-band Hubble Space Telescope imaging obtained as part of the Cluster Lensing and Supernova survey with Hubble. Combining this with revised weak-lensing analyses of Subaru wide-field imaging with five-band Subaru + KPNO photometry, we place tight new constraints on the halo virial mass M
vir = (2.2 ± 0.2) × 1015 M☼ h–1 70 (within rvir ≈ 3 Mpc h–1 70 ) and concentration cvir = 6.2 ± 0.3 when assuming a spherical halo. This agrees broadly with average c(M, z) predictions from recent ΛCDM simulations, which span 5 ≲ 〈 c〉 ≲ 8. Our most significant systematic uncertainty is halo elongation along the line of sight (LOS). To estimate this, we also derive a mass profile based on archival Chandra X-ray observations and find it to be ∼35% lower than our lensing-derived profile at r2500 ∼ 600 kpc. Agreement can be achieved by a halo elongated with a ∼2:1 axis ratio along our LOS. For this elongated halo model, we find Mvir = (1.7 ± 0.2) × 1015 M☼ h–1 70 and cvir = 4.6 ± 0.2, placing rough lower limits on these values. The need for halo elongation can be partially obviated by non-thermal pressure support and, perhaps entirely, by systematic errors in the X-ray mass measurements. We estimate the effect of background structures based on MMT/Hectospec spectroscopic redshifts and find that these tend to lower Mvir further by ∼7% and increase cvir by ∼5%. [ABSTRACT FROM AUTHOR]- Published
- 2012
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19. A BRIGHTEST CLUSTER GALAXY WITH AN EXTREMELY LARGE FLAT CORE.
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Postman, Marc, Lauer, Tod R., Donahue, Megan, Graves, Genevieve, Coe, Dan, Moustakas, John, Koekemoer, Anton, Bradley, Larry, Ford, Holland C., Grillo, Claudio, Zitrin, Adi, Lemze, Doron, Broadhurst, Tom, Moustakas, Leonidas, Ascaso, Begoña, Medezinski, Elinor, and Kelson, Daniel
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GALAXY clusters ,SUPERNOVAE spectra ,PHOTOMETRY ,STELLAR luminosity function - Abstract
Hubble Space Telescope images of the galaxy cluster A2261, obtained as part of the Cluster Lensing And Supernova survey with Hubble, show that the brightest galaxy in the cluster, A2261-BCG, has the largest core yet detected in any galaxy. The cusp radius of A2261-BCG is 3.2 kpc, twice as big as the next largest core known, and ∼3 × bigger than those typically seen in the most luminous brightest cluster galaxies. The morphology of the core in A2261-BCG is also unusual, having a completely flat interior surface brightness profile, rather than the typical shallow cusp rising into the center. This implies that the galaxy has a core with constant or even centrally decreasing stellar density. Interpretation of the core as an end product of the “scouring” action of a binary supermassive black hole implies a total black hole mass ∼10
10 M☼ from the extrapolation of most relationships between core structure and black hole mass. The core falls 1σ above the cusp radius versus galaxy luminosity relation. Its large size in real terms, and the extremely large black hole mass required to generate it, raises the possibility that the core has been enlarged by additional processes, such as the ejection of the black holes that originally generated the core. The flat central stellar density profile is consistent with this hypothesis. The core is also displaced by 0.7 kpc from the center of the surrounding envelope, consistent with a local dynamical perturbation of the core. [ABSTRACT FROM AUTHOR]- Published
- 2012
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20. PROFILES OF DARK MATTER VELOCITY ANISOTROPY IN SIMULATED CLUSTERS.
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Lemze, Doron, Wagner, Rick, Rephaeli, Yoel, Sadeh, Sharon, Norman, Michael L., Barkana, Rennan, Broadhurst, Tom, Ford, Holland, and Postman, Marc
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GALAXY clusters , *DARK matter , *ANISOTROPY , *GALACTIC halos , *GALACTIC redshift , *GALAXY spectra - Abstract
We report statistical results for dark matter (DM) velocity anisotropy, β, from a sample of some 6000 cluster-size halos (at redshift zero) identified in a ΛCDM hydrodynamical adaptive mesh refinement simulation performed with the ENZO code. These include profiles of β in clusters with different masses, relaxation states, and at several redshifts, modeled both as spherical and triaxial DM configurations. Specifically, although we find a large scatter in the DM velocity anisotropy profiles of different halos (across elliptical shells extending to at least ∼1.5rvir), universal patterns are found when these are averaged over halo mass, redshift, and relaxation stage. These are characterized by a very small velocity anisotropy at the halo center, increasing outward to ∼0.27 and leveling off at ∼0.2rvir. Indirect measurements of the DM velocity anisotropy fall on the upper end of the theoretically expected range. Though measured indirectly, the estimations are derived by using two different surrogate measurements—X-ray and galaxy dynamics. Current estimates of the DM velocity anisotropy are based on a very small cluster sample. Increasing this sample will allow theoretical predictions to be tested, including the speculation that the decay of DM particles results in a large velocity boost. We also find, in accord with previous works, that halos are triaxial and likely to be more prolate when unrelaxed, whereas relaxed halos are more likely to be oblate. Our analysis does not indicate that there is significant correlation (found in some previous studies) between the radial density slope, γ, and β at large radii, 0.3 rvir < r < rvir. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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21. QUANTIFYING THE COLLISIONLESS NATURE OF DARK MATTER AND GALAXIES IN A1689.
- Author
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Lemze, Doron, Rephaeli, Yoel, Barkana, Rennan, Broadhurst, Tom, Wagner, Rick, and Norman, Mike L.
- Published
- 2011
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