Search Results - "Hartmann, Lee"

Accretion onto Pre-Main-Sequence Stars by Hartmann, Lee, Herczeg, Gregory, Calvet, Nuria

“…Accretion through circumstellar disks plays an important role in star formation and in establishing the properties of the regions in which planets form and…”
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On the Formation of Multiple Concentric Rings and Gaps in Protoplanetary Disks by Bae, Jaehan, Zhu, Zhaohuan, Hartmann, Lee

“…As spiral waves driven by a planet in a gaseous disk steepen into a shock, they deposit angular momentum, opening a gap in the disk. This has been well studied…”
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Angular Momenta, Magnetization, and Accretion of Protostellar Cores by Kuznetsova, Aleksandra, Hartmann, Lee, Heitsch, Fabian

“…Building on our previous hydrodynamic study of the angular momenta of cloud cores formed during gravitational collapse of star-forming molecular gas in…”
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PLANETARY SIGNATURES IN THE SAO 206462 (HD 135344B) DISK: A SPIRAL ARM PASSING THROUGH VORTEX? by Bae, Jaehan, Zhu, Zhaohuan, Hartmann, Lee

“…ABSTRACT The disk surrounding SAO 206462, an 8 Myr old Herbig Ae star, has recently been reported to exhibit spiral arms, an asymmetric dust continuum, and a…”
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THE DEPENDENCE OF STAR FORMATION EFFICIENCY ON GAS SURFACE DENSITY by Burkert, Andreas, Hartmann, Lee

“…Studies by Lada et al. and Heiderman et al. have suggested that star formation mostly occurs above a threshold in gas surface density capital sigma of capital…”
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Bondi–Hoyle–Littleton accretion and the upper-mass stellar initial mass function by Ballesteros-Paredes, Javier, Hartmann, Lee W., Pérez-Goytia, Nadia, Kuznetsova, Aleksandra

“…We report on a series of numerical simulations of gas clouds with self-gravity forming sink particles, adopting an isothermal equation of state to isolate the…”
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DUST FILTRATION BY PLANET-INDUCED GAP EDGES: IMPLICATIONS FOR TRANSITIONAL DISKS by ZHAOHUAN ZHU, NELSON, Richard P, RUOBING DONG, ESPAILLAT, Catherine, HARTMANN, Lee

“…By carrying out two-dimensional two-fluid global simulations, we have studied the response of dust to gap formation by a single planet in the gaseous component…”
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Transitional and Pre-transitional Disks: Gap Opening by Multiple Planets? by Zhu, Zhaohuan, Nelson, Richard P, Hartmann, Lee, Espaillat, Catherine, Calvet, Nuria

“…We use two-dimensional hydrodynamic simulations of viscous disks to examine whether dynamically interacting multiple giant planets can explain the large gaps…”
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Accretion in Evolved and Transitional Disks in CEP OB2: Looking for the Origin of the Inner Holes by Sicilia-Aguilar, Aurora, Henning, Thomas, Hartmann, Lee W

“…We present accretion rates for a large number of solar-type stars in the Cep OB2 region, based on U-band observations. Our study comprises 95 members of the…”
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The Gould's Belt Distances Survey (GOBELINS). V. Distances and Kinematics of the Perseus Molecular Cloud by Ortiz-León, Gisela N., Loinard, Laurent, Dzib, Sergio A., Galli, Phillip A. B., Kounkel, Marina, Mioduszewski, Amy J., Rodríguez, Luis F., Torres, Rosa M., Hartmann, Lee, Boden, Andrew F., Evans, Neal J., Briceño, Cesar, Tobin, John J.

“…We derive the distance and structure of the Perseus molecular cloud by combining trigonometric parallaxes from Very Long Baseline Array (VLBA) observations,…”
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THE SPIRAL WAVE INSTABILITY INDUCED BY A GIANT PLANET. I. PARTICLE STIRRING IN THE INNER REGIONS OF PROTOPLANETARY DISKS by Bae, Jaehan, Nelson, Richard P., Hartmann, Lee

“…ABSTRACT We have recently shown that spiral density waves propagating in accretion disks can undergo a parametric instability by resonantly coupling with and…”
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Gravity or turbulence? - II. Evolving column density probability distribution functions in molecular clouds by Ballesteros-Paredes, Javier, Vázquez-Semadeni, Enrique, Gazol, Adriana, Hartmann, Lee W., Heitsch, Fabian, Colín, Pedro

“…It has been recently shown that molecular clouds do not exhibit a unique shape for the column density probability distribution function (N-PDF). Instead,…”
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Rapid star formation and global gravitational collapse by Hartmann, Lee, Ballesteros-Paredes, Javier, Heitsch, Fabian

“…Most young stars in nearby molecular clouds have estimated ages of 1-2 Myr, suggesting that star formation is rapid. However, small numbers of stars in these…”
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Flows, Fragmentation, and Star Formation. I. Low-Mass Stars in Taurus by Hartmann, Lee

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Magnetic suppression of turbulence and the star formation activity of molecular clouds by Zamora-Avilés, Manuel, Vázquez-Semadeni, Enrique, Körtgen, Bastian, Banerjee, Robi, Hartmann, Lee

“…Abstract We present magnetohydrodynamic simulations aimed at studying the effect of the magnetic suppression of turbulence (generated through various…”
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Multiple Spiral Arms in the Disk around Intermediate-mass Binary HD 34700A by Monnier, John D., Harries, Tim J., Bae, Jaehan, Setterholm, Benjamin R., Laws, Anna, Aarnio, Alicia, Adams, Fred C., Andrews, Sean, Calvet, Nuria, Espaillat, Catherine, Hartmann, Lee, Kraus, Stefan, McClure, Melissa, Miller, Chris, Oppenheimer, Rebecca, Wilner, David, Zhu, Zhaohuan

“…We present the first images of the transition disk around the close binary system HD 34700A in polarized scattered light using the Gemini Planet Imager…”
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Gravitational Focusing and the Star Cluster Initial Mass Function by Kuznetsova, Aleksandra, Hartmann, Lee, Burkert, Andreas

“…We discuss the possibility that gravitational focusing is responsible for the power-law mass function of star clusters . This power law can be produced…”
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The Role of Gravity in Producing Power-law Mass Functions by Kuznetsova, Aleksandra, Hartmann, Lee, Heitsch, Fabian, Ballesteros-Paredes, Javier

“…Numerical simulations of star formation have found that a power-law mass function can develop at high masses. In a previous paper, we employed isothermal…”
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The Gould's Belt Distances Survey (GOBELINS). IV. Distance, Depth, and Kinematics of the Taurus Star-forming Region by Galli, Phillip A. B., Loinard, Laurent, Ortiz-Léon, Gisela N., Kounkel, Marina, Dzib, Sergio A., Mioduszewski, Amy J., Rodríguez, Luis F., Hartmann, Lee, Teixeira, Ramachrisna, Torres, Rosa M., Rivera, Juana L., Boden, Andrew F., Evans II, Neal J., Briceño, Cesar, Tobin, John J., Heyer, Mark

“…We present new trigonometric parallaxes and proper motions of young stellar objects in the Taurus molecular cloud complex from observations collected with the…”
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On the Structure of the Orion A Cloud and the Formation of the Orion Nebula Cluster by Hartmann, Lee, Burkert, Andreas

“…We suggest that the Orion A cloud is gravitationally collapsing on large scales, and is producing the Orion Nebula Cluster through the focusing effects of…”
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