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Circumstellar gas and dust emission and mass loss from evolved stars
Orbiting a star Gas Dust emissions Evolution of stars
2014/12/9
This dissertation presents a study of the circumstellar gas and dust emission and their relation to the mass-loss in evolved stars. Considering the physical process of heating and cooling of the dust,...
Investigation of Herbig Ae /Be stars in the near -infrared with a long baseline interferometer
Long baseline Stars Near infrared interferometry The dust
2014/12/9
We have conducted the first systematic study of Herbig Ae/Be stars using the technique of long baseline spatial interferometry in the near-infrared, with the objective of characterizing the distributi...
Iron and helium emission lines in classical T Tauri stars
Emissions Molecular cloud Emissions High resolution Echelle spectrum The center of mass velocity
2014/12/9
Results are presented for the He emission in 31 CTTS from the Taurus-Auriga molecular cloud spanning two orders of magnitude in the mass accretion rate, and for the Fe emission in DR Tau, based on a s...
Low mass stars and the structure of the Pleiades cluster
Low quality The Pleiades cluster Micron Near infrared photometric method The observatory
2014/12/9
This thesis presents a large scale search for new low mass members of the Pleiades cluster using near-infrared photometry from the Two Micron All Sky Survey and proper motions derived from digitized P...
One-micron spectroscopic studies of accretion and outflow in T Tauri stars
High resolution spectrum Classical T Taurus Stars Spectrum Air calibrator The stars
2014/12/9
High-resolution spectroscopy of classical T Tauri stars (CTTS) at one micron yields new insight into the interaction of accretion disks, outflowing gas, and the central stars. Eighty-one 0.95–1.12 μm ...
Massive black holes spewing out radio-frequency-emitting particles at near-light speed can block formation of new stars in aging galaxies, a study has found.
Formation and large-scale confinement of jets emitted by young stars finally elucidated
young stars plane scientists
2014/10/30
An international team of scientists has succeeded in explaining the formation and propagation over astronomical distances of jetsof matter emitted by young stars—one of the most fascinating mysteries ...
Making stars
astronomy universe Light pollution
2014/10/16
Like so many other children, Fabienne Bastien did not like to go to sleep at bedtime
She recalls her mother lying alongside her, telling her to look out her window into the night sky because her guar...
Imagine living on an exoplanet with two suns. One, you orbit and the other is a very bright, nearby neighbor looming large in your sky. With this “second sun” in the sky, nightfall might be a rare eve...
Mixing in star-forming clouds explains why sibling stars look alike（图）
sibling star-forming clouds
2014/9/12
The chemical uniformity of stars in the same cluster is the result of turbulent mixing in the clouds of gas where star formation occurs, according to a study by astrophysicists at the University of Ca...
Analyzing sun-like stars that eat Earth-like planets
Analyzing sun-like stars eat Earth-like planets
2014/6/12
Some Sun-like stars are ‘Earth-eaters.’ During their development they ingest large amounts of the rocky material from which ‘terrestrial’ planets like Earth, Mars and Venus are made.
'Death stars' in Orion blast planets before they even form（图）
Death stars they even form planets
2014/3/20
The Orion Nebula is home to hundreds of young stars and even younger protostars known as proplyds. Many of these nascent systems will go on to develop planets, while others will have their planet-form...
Surprising new class of 'hypervelocity stars' discovered escaping the galaxy（图）
hypervelocity stars galaxy
2014/3/17
Top and side views of the Milky Way galaxy show the location of four of the new class of hypervelocity stars. These are sun-like stars that are moving at speeds of more than a million miles per hour r...
The study of neutron stars is a topic of central interest in the investigation of the properties of strongly compressed hadronic matter. Whereas in heavy-ion collisions the fireball, created in the co...
Vibrational Instability of Metal-Poor Low-Mass Main-Sequence Stars
Vibrational Instability Metal-Poor Low-Mass Main-Sequence Stars
2012/2/24
We find that low-degree low-order g-modes become unstable in metal-poor low-mass stars due to the $\varepsilon$-mechanism of the pp-chain. Since the outer convection zone of these stars is limited onl...