Related papers: Alignment Between Flattened Protostellar Infall En…
We have developed a modified form of the equations of smoothed particle magnetohydrodynamics which are stable in the presence of very steep density gradients. Using this formalism, we have performed simulations of the collapse of magnetised…
We investigate the roles of magnetic fields and ambipolar diffusion during prestellar core formation in turbulent giant molecular clouds (GMCs), using three-dimensional numerical simulations. Our simulations focus on the shocked layer…
Massive young stellar objects (YSOs), like low-mass YSOs, are thought to be surrounded by optically thick envelopes and/or discs and are observed to have associated regions that produce polarized light at near-infrared wavelengths. These…
We present JCMT POL-2 850 um dust polarization observations and Mimir H band stellar polarization observations toward the starless core L1512. We detect the highly-ordered core-scale magnetic field traced by the POL-2 data, of which the…
Non-ideal magnetohydrodynamic effects that rule the coupling of the magnetic field to the circumstellar gas during the low-mass star formation process depend heavily on the local physical conditions, such as the ionization fraction of the…
The magnetic vortex structure, an important ground state configuration in micron and sub-micron sized ferromagnetic thin film platelets, is characterized by a curling in-plane magnetization and, in the center, a minuscule region with…
We present an observational study of the protostellar core B335 harboring a low-mass Class 0 source. The observations of the H13CO+(J=1-0) line emission were carried out using the Nobeyama 45 m telescope and Nobeyama Millimeter Array. Our…
We present integrated polarization properties of nearby spiral galaxies at 4.8 GHz, and models for the integrated polarization of spiral galaxy disks as a function of inclination. Spiral galaxies in our sample have observed integrated…
The HH 1-2 region in the L1641 molecular cloud was observed in the near-IR J, H, and Ks bands, and imaging polarimetry was performed. Seventy six point-like sources were detected in all three bands. The near-IR polarizations of these…
(abridged) The nature of early Class 0/I protostellar discs is not clearly understood. Early protostellar discs are needed to drive molecular outflows and jets observed in star forming regions, but there has been some debate to how they…
Crutcher, Hakobian, and Troland (2009) used OH Zeeman observations of four nearby molecular dark clouds to show that the ratio of mass to magnetic flux was smaller in the ~0.1 pc cores than in the ~1 pc envelopes, in contradiction to the…
Building on our previous hydrodynamic study of the angular momenta of cloud cores formed during gravitational collapse of star-forming molecular gas in our previous work, we now examine core properties assuming ideal magnetohydrodynamics…
The collapse and fragmentation of initially prolate and oblate, magnetic molecular clouds is calculated in three dimensions with a gravitational, radiative hydrodynamics code. The code includes magnetic field effects in an approximate…
We conducted IRAM-30m C18O (2-1) and SMA 1.3mm continuum, 12CO (2-1), and C18O (2-1) observations toward the Class 0/I protostar L1455 IRS1 in Perseus. The IRAM results show L1455 IRS1 located in a dense core of 0.05 pc in size with a mass…
We present polarization observations of the dust continuum emission from IRAS 16293 which is a Class 0 protostar and is known to have at least two components, source A and B. These measurements were conducted by the Submillimeter Array…
Using numerical hydrodynamics simulations we studied the gravitational collapse of pre-stellar cores of sub-solar mass embedded into a low-density external environment. Four models with different magnitude and direction of rotation of the…
Many mechanisms have been proposed to alleviate the magnetic catastrophe, which prevents the Keplerian disk from forming inside a collapsing magnetized core. Such propositions include inclined field and non-ideal magnetohydrodynamics…
We present Submillimeter Array 880 $\mu$m dust polarization observations of six massive dense cores in the DR21 filament. The dust polarization shows complex magnetic field structures in the massive dense cores with sizes of 0.1 pc, in…
The pre-stellar cores in which low mass stars form are generally well magnetized. Our simulations show that early protostellar discs are massive and experience strong magnetic torques in the form of magnetic braking and protostellar…
We report our observational results of 870 $\mu$m continuum emission and its linear polarization in the massive star formation site W51 e2/e8. Inferred from the linear polarization maps, the magnetic field in the plane of sky (B$_{\bot}$)…