Continuum Description of the Cytoskeleton: Ring Formation in the Cell Cortex

Kavli Affiliate: Marileen Dogterom | Summary:Motivated by the formation of ring-like filament structures in the cortex of plant and animal cells, we study the dynamics of a two-dimensional layer of cytoskeletal filaments and motor proteins near a surface by a general continuum theory. As a result of active processes, dynamic patterns of filament orientation and […]


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Continuum approach to wide shear zones in quasi-static granular matter

Kavli Affiliate: Martin Depken | Summary:Slow and dense granular flows often exhibit narrow shear bands, making them ill-suited for a continuum description. However, smooth granular flows have been shown to occur in specific geometries such as linear shear in the absence of gravity, slow inclined plane flows and, recently, flows in split-bottom Couette geometries. The […]


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Spurious phase in a model for traffic on a bridge

Kavli Affiliate: David Erickson | Summary:We present high-precision Monte Carlo data for the phase diagram of a two-species driven diffusive system, reminiscent of traffic across a narrow bridge. Earlier studies reported two phases with broken symmetry; the existence of one of these has been the subject of some debate. We show that the disputed phase […]


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GALEX Observations of an Energetic Ultraviolet Flare on the dM4e Star GJ 3685A

Kavli Affiliate: Richard D. Robinson | Summary:The Galaxy Evolution Explorer (GALEX) satellite has obtained high time resolution ultraviolet photometry during a large flare on the M4 dwarf star GJ 3685A. Simultaneous NUV (1750 – 2800A) and FUV (1350 – 1750A) time-tagged photometry with time resolution better than 0.1 s shows that the overall brightness in […]


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MACHOs in M31? Absence of evidence but not evidence of absence

Kavli Affiliate: Geza Gyuk | Summary:We present results of a microlensing survey toward the Andromeda Galaxy (M31) carried out during four observing seasons at the Isaac Newton Telescope (INT). This survey is part of the larger microlensing survey toward M31 performed by the Microlensing Exploration of the Galaxy and Andromeda (MEGA) collaboration. Using a fully […]


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HST Imaging of MEGA Microlensing Candidates in M31

Kavli Affiliate: Geza Gyuk | Summary:We investigate $HST$/ACS and WFPC2 images at the positions of five candidate microlensing events from a large survey of variability in M31 (MEGA). Three closely match unresolved sources, and two produce only flux upper limits. All are confined to regions of the color-magnitude diagram where stellar variability is unlikely to […]


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Model atmospheres and X-ray spectra of iron-rich bursting neutron stars. II. Iron rich Comptonized Spectra

Kavli Affiliate: P. C. Joss | Summary:This paper presents the set of plane-parallel model atmosphere equations for a very hot neutron star (X-ray burst source). The model equations assume both hydrostatic and radiative equilibrium, and the equation of state of an ideal gas in local thermodynamic equilibrium (LTE). The equation of radiative transfer includes terms […]


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Missing Quasiparticles and the Chemical Potential Puzzle in the Doping Evolution of the Cuprate Superconductors

Kavli Affiliate: Kyle Shen | First 5 Authors: K. M. Shen, K. M. Shen, , , | Summary: The evolution of Ca$_2-x$Na$_x$CuO$_2$Cl$_2$ from Mott insulator to superconductor was studied using angle-resolved photoemission spectroscopy. By measuring both the excitations near the Fermi energy as well as non-bonding states, we tracked the doping dependence of the electronic […]


Continue.. Missing Quasiparticles and the Chemical Potential Puzzle in the Doping Evolution of the Cuprate Superconductors

Missing Quasiparticles and the Chemical Potential Puzzle in the Doping Evolution of the Cuprate Superconductors

Kavli Affiliate: Kyle Shen | First 5 Authors: K. M. Shen, K. M. Shen, , , | Summary: The evolution of Ca$_2-x$Na$_x$CuO$_2$Cl$_2$ from Mott insulator to superconductor was studied using angle-resolved photoemission spectroscopy. By measuring both the excitations near the Fermi energy as well as non-bonding states, we tracked the doping dependence of the electronic […]


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Chandra Observations and Monte Carlo Simulations of the Grain-Scattered Halo of the Binary X-Ray Pulsar 4U 1538-52

Kavli Affiliate: George Clark | Summary:Properties of the X-ray halo of the eclipsing X-ray pulsar 4U 1538-52 are derived from a 25 ksec observation by the Chandra X-Ray Observatory. Profiles of the halo, compiled in two energy ranges, 2 to 4 keV and 4 to 6 keV, and three time intervals before and after an […]


Continue.. Chandra Observations and Monte Carlo Simulations of the Grain-Scattered Halo of the Binary X-Ray Pulsar 4U 1538-52