Search Results - "Simon, Jacob"

The Streaming Instability Cannot Form Planetesimals from Millimeter-size Grains in Pressure Bumps by Carrera, Daniel, Simon, Jacob B.

“…Abstract We present evidence that it is unlikely that the streaming instability (SI) can form planetesimals from millimeter grains inside axisymmetric pressure…”
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THE MASS AND SIZE DISTRIBUTION OF PLANETESIMALS FORMED BY THE STREAMING INSTABILITY. I. THE ROLE OF SELF-GRAVITY by Simon, Jacob B., Armitage, Philip J., Li, Rixin, Youdin, Andrew N.

“…ABSTRACT We study the formation of planetesimals in protoplanetary disks from the gravitational collapse of solid over-densities generated via the streaming…”
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Monoaminergic Neuromodulation of Sensory Processing by Jacob, Simon N, Nienborg, Hendrikje

“…All neuronal circuits are subject to neuromodulation. Modulatory effects on neuronal processing and resulting behavioral changes are most commonly reported for…”
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Complementary Roles for Primate Frontal and Parietal Cortex in Guarding Working Memory from Distractor Stimuli by Jacob, Simon Nikolas, Nieder, Andreas

“…Prefrontal cortex (PFC) and posterior parietal cortex are important for maintaining behaviorally relevant information in working memory. Here, we challenge the…”
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Demographics of Planetesimals Formed by the Streaming Instability by Li, Rixin, Youdin, Andrew N., Simon, Jacob B.

“…The streaming instability (SI) is a mechanism to aerodynamically concentrate solids in protoplanetary disks and facilitate the formation of planetesimals…”
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Turbulence in the TW Hya Disk by Flaherty, Kevin M., Hughes, A. Meredith, Teague, Richard, Simon, Jacob B., Andrews, Sean M., Wilner, David J.

“…Turbulence is a fundamental parameter in models of grain growth during the early stages of planet formation. As such, observational constraints on its…”
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Strongly magnetized accretion discs: structure and accretion from global magnetohydrodynamic simulations by Mishra, Bhupendra, Begelman, Mitchell C, Armitage, Philip J, Simon, Jacob B

“…ABSTRACT We use global magnetohydrodynamic simulations to study the influence of net vertical magnetic fields on the structure of geometrically thin…”
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Accretion disc dynamo activity in local simulations spanning weak-to-strong net vertical magnetic flux regimes by Salvesen, Greg, Simon, Jacob B., Armitage, Philip J., Begelman, Mitchell C.

“…Strongly magnetized accretion discs around black holes have attractive features that may explain enigmatic aspects of X-ray binary behaviour. The structure and…”
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Magnetically driven accretion in protoplanetary discs by Simon, Jacob B., Lesur, Geoffroy, Kunz, Matthew W., Armitage, Philip J.

“…We characterize magnetically driven accretion at radii between 1 and 100 au in protoplanetary discs, using a series of local non-ideal magnetohydrodynamic…”
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Turbulence Regulates the Rate of Planetesimal Formation via Gravitational Collapse by Gole, Daniel A., Simon, Jacob B., Li, Rixin, Youdin, Andrew N., Armitage, Philip J.

“…We study how the interaction between the streaming instability (SI) and intrinsic gas-phase turbulence affects planetesimal formation via gravitational…”
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The Mass and Size Distribution of Planetesimals Formed by the Streaming Instability. II. The Effect of the Radial Gas Pressure Gradient by Abod, Charles P., Simon, Jacob B., Li, Rixin, Armitage, Philip J., Youdin, Andrew N., Kretke, Katherine A.

“…The streaming instability concentrates solid particles in protoplanetary disks, leading to gravitational collapse into planetesimals. Despite its key role in…”
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On the Numerical Robustness of the Streaming Instability: Particle Concentration and Gas Dynamics in Protoplanetary Disks by Li, Rixin, Youdin, Andrew N., Simon, Jacob B.

“…The streaming instability (SI) is a mechanism to concentrate solids in protoplanetary disks. Nonlinear particle clumping from the SI can trigger gravitational…”
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A Three-dimensional View of Turbulence: Constraints on Turbulent Motions in the HD 163296 Protoplanetary Disk Using DCO by Flaherty, Kevin M., Hughes, A. Meredith, Rose, Sanaea C., Simon, Jacob B., Qi, Chunhua, Andrews, Sean M., Kóspál, Ágnes, Wilner, David J., Chiang, Eugene, Armitage, Philip J., Bai, Xue-ning

“…Gas kinematics are an important part of the planet formation process. Turbulence influences planetesimal growth and migration from the scale of submicron dust…”
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Emergent mesoscale phenomena in magnetized accretion disc turbulence by Simon, Jacob B., Beckwith, Kris, Armitage, Philip J.

“…We study how the structure and variability of magnetohydrodynamic (MHD) turbulence in accretion discs converge with domain size. Our results are based on a…”
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Measuring Turbulent Motion in Planet-forming Disks with ALMA: A Detection around DM Tau and Nondetections around MWC 480 and V4046 Sgr by Flaherty, Kevin, Hughes, A. Meredith, Simon, Jacob B., Qi, Chunhua, Bai, Xue-Ning, Bulatek, Alyssa, Andrews, Sean M., Wilner, David J., Kóspál, Ágnes

“…Turbulence is a crucial factor in many models of planet formation, but it has only been directly constrained among a small number of planet-forming disks…”
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Origin of Weak Turbulence in the Outer Regions of Protoplanetary Disks by Simon, Jacob B., Bai, Xue-Ning, Flaherty, Kevin M., Hughes, A. Meredith

“…The mechanism behind angular momentum transport in protoplanetary disks, and whether this transport is turbulent in nature, is a fundamental issue in planet…”
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TURBULENCE IN THE OUTER REGIONS OF PROTOPLANETARY DISKS. II. STRONG ACCRETION DRIVEN BY A VERTICAL MAGNETIC FIELD by Simon, Jacob B, Bai, Xue-Ning, Armitage, Philip J, Stone, James M, Beckwith, Kris

“…We carry out a series of local, vertically stratified shearing box simulations of protoplanetary disks that include ambipolar diffusion and a net vertical…”
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Relating magnitudes: the brain's code for proportions by Jacob, Simon N, Vallentin, Daniela, Nieder, Andreas

“…Whereas much is known about how we categorize and reason based on absolute quantity, data exploring ratios of quantities, as in proportions and fractions, are…”
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Dopamine Receptors Differentially Enhance Rule Coding in Primate Prefrontal Cortex Neurons by Ott, Torben, Jacob, Simon Nikolas, Nieder, Andreas

“…Flexibly applying abstract rules is a hallmark feature of executive functioning represented by prefrontal cortex (PFC) neurons. Prefrontal networks are…”
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EFFICIENCY OF PARTICLE TRAPPING IN THE OUTER REGIONS OF PROTOPLANETARY DISKS by Simon, Jacob B, Armitage, Philip J

“…We investigate the strength of axisymmetric local pressure maxima (zonal flows) in the outer regions of protoplanetary disks, where ambipolar diffusion reduces…”
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