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Finner, Kyle,Jee, M. James,Golovich, Nathan,Wittman, David,Dawson, William,Gruen, Daniel,Koekemoer, Anton M.,Lemaux, Brian C.,Seitz, Stella American Astronomical Society 2017 The Astrophysical journal Vol.851 No.1
<P>The second most significant detection of the Planck Sunyaev-Zel'dovich survey, PLCK G287.0+32.9 (z = 0.385), boasts two similarly bright radio relics and a radio halo. One radio relic is located similar to 400 kpc NW of the X-ray peak and the other similar to 2.8 Mpc to the SE. This large difference suggests that a complex merging scenario is required. A key missing puzzle for the merging scenario reconstruction is the underlying dark matter distribution in high resolution. We present a joint Subaru Telescope and Hubble Space Telescope weak-lensing analysis of the cluster. Our analysis shows that the mass distribution features four significant substructures. Of the substructures, a primary cluster of mass M-200c = 1.59(-0.22)(+0.25) x 10(15) h(70)(-1) M-circle dot dominates the weak-lensing signal. This cluster is likely to be undergoing a merger with one (or more) subcluster whose mass is approximately a factor of 10 lower. One candidate is the subcluster of mass M-200c = 1.16(-0.13)(+0.15) x 10(14) h(70)(-1) M-circle dot located similar to 400 kpc to the SE. The location of this subcluster suggests that its interaction with the primary cluster could be the source of the NW radio relic. Another subcluster is detected similar to 2 Mpc to the SE of the X-ray peak with mass M-200c =1.68(-0.20)(+0.22) x 10(14) h(70)(-1) M-circle dot. This SE subcluster is in the vicinity of the SE radio relic and may have created the SE radio relic during a past merger with the primary cluster. The fourth subcluster, M-200c = 1.87(-0.22)(+0.24) x 10(14) h(70)(-1) M-circle dot, is NW of the X-ray peak and beyond the NW radio relic.</P>
Jee, M. James,Dawson, William A.,Stroe, Andra,Wittman, David,van Weeren, Reinout J.,Brü,ggen, Marcus,Bradad,, Maruš,a,Rö,ttgering, Huub American Astronomical Society 2016 The Astrophysical journal Vol.817 No.2
<P>The galaxy cluster RX J0603.3+4214. at z-0.225 is one of the rarest clusters boasting an extremely large (similar to 2 Mpc) radio. relic. Because of the remarkable morphology of the relic, the cluster is nicknamed the. 'Toothbrush Cluster.' Although the cluster's underlying mass distribution is one of the critical pieces of information needed to reconstruct the merger scenario responsible for the puzzling radio. relic morphology, its proximity to the Galactic plane b similar to 10 degrees has imposed significant observational challenges. We present a high-resolution weak-lensing study of the cluster with Subaru/Suprime Cam and Hubble Space Telescope imaging data. Our mass reconstruction reveals that the cluster is composed of complicated dark matter substructures closely tracing the galaxy distribution, in contrast, however, with the relatively simple binary X-ray morphology. Nevertheless, we find that the cluster mass is still dominated by the two most massive clumps aligned north-south with a similar to 3: 1 mass ratio (M-200 = 6.29(-1.62)(+2.24) x 10(14) M-circle dot and 1.98(-0.74)(+1.24) x 10(14) M-circle dot for the northern and southern clumps, respectively). The southern mass peak is similar to 2' offset toward the south with respect to the corresponding X-ray peak, which has a 'bullet'-like morphology pointing south. Comparison of the current weak-lensing result with the X-ray, galaxy, and radio. relic suggests that perhaps the dominant mechanism responsible for the observed relic may be a highspeed collision of the two most massive subclusters, although the peculiarity of the morphology necessitates involvement of additional subclusters. Careful numerical simulations should follow in order to obtain more complete understanding of the merger scenario utilizing all existing observations.</P>
Golovich, Nathan,Weeren, Reinout J. van,Dawson, William A.,Jee, M. James,Wittman, David American Astronomical Society 2017 The Astrophysical journal Vol.838 No.2
<P>We present and analyze a rich data set including Subaru/SuprimeCam, HST/Advanced Camera for Surveys and Wide Field Camera 3, Keck/DEIMOS, Chandra/ACIS-I, and JVLA/C and D array for the merging cluster of galaxies ZwCl 0008.8+ 5215. With a joint Subaru+ HST weak gravitational lensing analysis, we identify two dominant subclusters and estimate the masses to be M-200 = 5.8(-1.8)(+2.8) x 10(14) M-circle dot. We estimate the projected separation between the two subclusters to be 924(-206)(+243) kpc. We perform a clustering analysis of spectroscopically confirmed cluster member galaxies and estimate the line-of-sight velocity difference between the two subclusters to be 92 +/- 164 km s(-1). We further motivate, discuss, and analyze the merger scenario through an analysis of the 42 ks of Chandra/ACIS-I and JVLA/C and D array polarization data. The X-ray surface brightness profile reveals a merging gas-core reminiscent of the Bullet Cluster. The global X-ray luminosity in the 0.5-7.0 keV band is 1.7. +/- 0.1 x 10(44) erg s(-1) and the global X-ray temperature is 4.90 +/- 0.13 keV. The radio relics are polarized up to 40%,. and along with the masses, velocities, and positions of the two subclusters, we input these quantities into a Monte Carlo dynamical analysis and estimate the merger velocity at pericenter to be 1800(-300)(+400) km s(-1). This is a lower-mass version of the Bullet Cluster and therefore may prove useful in testing alternative models of dark matter (DM). We do not find significant offsets between DM and galaxies, but the uncertainties are large with the current lensing data. Furthermore, in the east, the BCG is offset from other luminous cluster galaxies, which poses a puzzle for defining DM-galaxy offsets.</P>
Jee, M. James,Tyson, J. Anthony,Hilbert, Stefan,Schneider, Michael D.,Schmidt, Samuel,Wittman, David American Astronomical Society 2016 The Astrophysical journal Vol.824 No.2
<P>We present a tomographic cosmic shear study from the Deep Lens Survey (DLS), which, providing a limiting magnitude r(lim) similar to 27 (5 sigma), is designed as a precursor Large Synoptic Survey Telescope (LSST) survey with an emphasis on depth. Using five tomographic redshift bins, we study their auto- and cross-correlations to constrain cosmological parameters. We use a luminosity-dependent nonlinear model to account for the astrophysical systematics originating from intrinsic alignments of galaxy shapes. We find that the cosmological leverage of the DLS is among the highest among existing > 10 deg(2) cosmic shear surveys. Combining the DLS tomography with the 9 yr results of the Wilkinson Microwave Anisotropy Probe (WMAP9) gives Omega(m) = 0.293(-0.014)(+0.012), sigma(8) = 0.833(-0.018)(+0.011), H-0 = 68.6(-1.2)(+1.4) km s(-1) Mpc(-1).4 1 1, and Omega(b) = 0.0475 +/- 0.0012 for Lambda CDM, reducing the uncertainties of the WMAP9-only constraints by similar to 50%. When we do not assume flatness for Lambda CDM, we obtain the curvature constraint Omega(k) = -0.010(-0.015)(+0.013) from the DLS+WMAP9 combination, which, however, is not well constrained when WMAP9 is used alone. The dark energy equation-of-state parameter w is tightly constrained when baryonic acoustic oscillation (BAO) data are added, yielding = - w -1.02(-0.09)(+0.10) with the DLS+WMAP9+BAO joint probe. The addition of supernova constraints further tightens the parameter to w = -1.03 +/- 0.03. Our joint constraints are fully consistent with the final Planck results and also with the predictions of a Lambda CDM universe.</P>