PH607lec08
... A large fraction of disk galaxies have bars: narrow linear structures crossing the face of the galaxy. In barred S0 galaxies the bar is often the only structure visible in the disk. In types SBa and later the bar often connects to a spiral pattern extending to larger radii (e.g. NGC 1300). Viewed fa ...
... A large fraction of disk galaxies have bars: narrow linear structures crossing the face of the galaxy. In barred S0 galaxies the bar is often the only structure visible in the disk. In types SBa and later the bar often connects to a spiral pattern extending to larger radii (e.g. NGC 1300). Viewed fa ...
A cold detached dust envelope around an oxygen-rich Mira
... boundary is required for the circumstellar dust envelope in this case (Hashimoto 1994, 1995). (4) Or, some circumstellar mechanisms other than dust grains may produce the infrared excess. For example, strong line emission from circumstellar molecules such as H2 O may cause the reddening. In any case ...
... boundary is required for the circumstellar dust envelope in this case (Hashimoto 1994, 1995). (4) Or, some circumstellar mechanisms other than dust grains may produce the infrared excess. For example, strong line emission from circumstellar molecules such as H2 O may cause the reddening. In any case ...
Unraveling the Helix Nebula: Its Structure and Knots
... 213 parsecs, which is based on the trigonometric parallax of the central star (Harris et al. 1997). This yields a scale of 1′′ = 3.19 x 1015 cm and the 5.45′ semimajor axis of the nebula (O2002) is then 0.33 pc. It is necessary to comment on the nomenclature used in this paper since different and so ...
... 213 parsecs, which is based on the trigonometric parallax of the central star (Harris et al. 1997). This yields a scale of 1′′ = 3.19 x 1015 cm and the 5.45′ semimajor axis of the nebula (O2002) is then 0.33 pc. It is necessary to comment on the nomenclature used in this paper since different and so ...
Constraining the star formation histories of spiral bulges
... processes have been proposed to produce this pre-enrichment. One possibility is an initial mass function (IMF) biased towards highmass stars in the early stages of galaxy formation. In this scenario the first few generations of stars generate large quantities of metals (Gibson & Matteucci 1997; Vazd ...
... processes have been proposed to produce this pre-enrichment. One possibility is an initial mass function (IMF) biased towards highmass stars in the early stages of galaxy formation. In this scenario the first few generations of stars generate large quantities of metals (Gibson & Matteucci 1997; Vazd ...
The formation of disc galaxies in high-resolution moving
... particles whereas the rest of the simulation volume is filled with progressively higher mass particles whose mass grows with distance from the target galaxy. This saves computational time while still ensuring the correct cosmological tidal field and mass infall rate for the forming target galaxy. Th ...
... particles whereas the rest of the simulation volume is filled with progressively higher mass particles whose mass grows with distance from the target galaxy. This saves computational time while still ensuring the correct cosmological tidal field and mass infall rate for the forming target galaxy. Th ...
SUB-KILOPARSEC IMAGING OF COOL MOLECULAR GAS IN
... Extensive effort has gone towards studying gas and dust both in the local universe and at high redshift in order to understand the physics and history of star formation. One of the most studied correlations is the powerlaw relationship between the gas surface density, Σgas , and the SFR surface dens ...
... Extensive effort has gone towards studying gas and dust both in the local universe and at high redshift in order to understand the physics and history of star formation. One of the most studied correlations is the powerlaw relationship between the gas surface density, Σgas , and the SFR surface dens ...
Introduction
... formation. I demonstrate that feedback from active nuclei is unlikely to be the dominant mechanism quenching star formation and driving the evolution of these late-type galaxies. In fact, galaxies with quenched star formation are typically gas deficient systems residing in the cluster environment, s ...
... formation. I demonstrate that feedback from active nuclei is unlikely to be the dominant mechanism quenching star formation and driving the evolution of these late-type galaxies. In fact, galaxies with quenched star formation are typically gas deficient systems residing in the cluster environment, s ...
MPhil Thesis - Final - Suzanne Knight
... white dwarfs make them ideal candidates for detecting low mass objects such as brown dwarfs and gas giant planets. ! Theoretical predictions generally agree that a star will consume and destroy close-in, low mass planets as it ascends the red giant and asymptotic giant branch evolutionary tracks, bu ...
... white dwarfs make them ideal candidates for detecting low mass objects such as brown dwarfs and gas giant planets. ! Theoretical predictions generally agree that a star will consume and destroy close-in, low mass planets as it ascends the red giant and asymptotic giant branch evolutionary tracks, bu ...
M sin i
... The Solar nebula was made of H y He, with a small fraction of heavy elements. About 4550 - 4400 million years ago these heavy elements condensed as dust in the inner disk, and as ice+dust in the outer disk. According to the Solar system formation theory, Jupiter must form beyond the ice line, at 5 A ...
... The Solar nebula was made of H y He, with a small fraction of heavy elements. About 4550 - 4400 million years ago these heavy elements condensed as dust in the inner disk, and as ice+dust in the outer disk. According to the Solar system formation theory, Jupiter must form beyond the ice line, at 5 A ...
PPT
... • Understanding of MRI through Lagrangian point of view • Consider differentially rotating plasma disk with vertical magnetic field (penetrate disk) in some gravitational field (stationary) • Put small radial perturbation in rotating plasma at radius r from rotation axis (angular momentum is conserv ...
... • Understanding of MRI through Lagrangian point of view • Consider differentially rotating plasma disk with vertical magnetic field (penetrate disk) in some gravitational field (stationary) • Put small radial perturbation in rotating plasma at radius r from rotation axis (angular momentum is conserv ...
Lokal fulltext - Chalmers Publication Library
... rings of planetesimals, remains. These rings of planetesimals are important for the circumstellar dust this thesis discusses. Gravitational influences from surrounding planets will create collisions in these rings. Such collisions result in the production of µm sized dust grains, or debris, that spr ...
... rings of planetesimals, remains. These rings of planetesimals are important for the circumstellar dust this thesis discusses. Gravitational influences from surrounding planets will create collisions in these rings. Such collisions result in the production of µm sized dust grains, or debris, that spr ...
The masses and spins of neutron stars and stellar
... mass and spin magnitude, which in turn tells us about the conditions in the pre-supernova star just before the collapse. In contrast, there is an ongoing debate about whether the spin direction of black holes can be altered substantially by accretion. As we will see, this has a significant impact on ...
... mass and spin magnitude, which in turn tells us about the conditions in the pre-supernova star just before the collapse. In contrast, there is an ongoing debate about whether the spin direction of black holes can be altered substantially by accretion. As we will see, this has a significant impact on ...
The Evolution of Isotope Ratios in the Milky Way Galaxy
... Isotope ratios have opened a new window into the study of the details of stellar evolution, supernovae, and galactic chemical evolution. We present the evolution of the isotope ratios of elemental abundances (from C to Zn) in the solar neighbourhood, bulge, halo, and thick disk, using chemical evolu ...
... Isotope ratios have opened a new window into the study of the details of stellar evolution, supernovae, and galactic chemical evolution. We present the evolution of the isotope ratios of elemental abundances (from C to Zn) in the solar neighbourhood, bulge, halo, and thick disk, using chemical evolu ...
Star Formation in the Rosette Complex
... A low resolution, single slit investigation by Hensberge et al. (1998) of 2 members and 3 field stars in the region of NGC 2244 yielded evidence that these were chemically peculiar, possibly magnetic stars. Hensberge et al. (2000) performed spectroscopic analysis of the binary member V578 Mon, which ...
... A low resolution, single slit investigation by Hensberge et al. (1998) of 2 members and 3 field stars in the region of NGC 2244 yielded evidence that these were chemically peculiar, possibly magnetic stars. Hensberge et al. (2000) performed spectroscopic analysis of the binary member V578 Mon, which ...
c Copyright by Jonathan C. McKinney, 2004
... (Run A). The dotted line indicates the thin disk value. The run has clearly entered a quasi-steady state. The evolution is relatively smooth with a small variation on a timescale τ ≈ 4 × 104 . This is the timescale for convective bubble formation (the low point in rest-mass accretion rate is when bu ...
... (Run A). The dotted line indicates the thin disk value. The run has clearly entered a quasi-steady state. The evolution is relatively smooth with a small variation on a timescale τ ≈ 4 × 104 . This is the timescale for convective bubble formation (the low point in rest-mass accretion rate is when bu ...
Observing Stellar Evolution
... Stellar evolution – refers to the stages in the lifetime of one star. When biologists talk about evolution they mean intergenerational evolution. While stars change from one generation to the next, the focus of this program is stellar lifetimes. Burning – The materials that comprise stars do not 'bu ...
... Stellar evolution – refers to the stages in the lifetime of one star. When biologists talk about evolution they mean intergenerational evolution. While stars change from one generation to the next, the focus of this program is stellar lifetimes. Burning – The materials that comprise stars do not 'bu ...