Metallicity maps
... but ram-pressure stripping is very important), they yield different metal distributions and have different time scales ram-pressure in the outskirts of clusters is sufficient to strip gas and form new stars inhomogeneous metallicity distribution, enriched material is not mixed immediately with I ...
... but ram-pressure stripping is very important), they yield different metal distributions and have different time scales ram-pressure in the outskirts of clusters is sufficient to strip gas and form new stars inhomogeneous metallicity distribution, enriched material is not mixed immediately with I ...
The Milky Way Galaxy 1 Introduction 2 Globular Clusters and
... Who first observed that the Milky Way is made up of an enormous number of stars? When did this occur, and what was the significance of the observation? ...
... Who first observed that the Milky Way is made up of an enormous number of stars? When did this occur, and what was the significance of the observation? ...
The Milky Way galaxy Contents Summary
... them to drift inwards. The outward thrust from the bar and the frictional inward drift balance just outside rcr , and gas accumulates here. This accumulation of gas near rcr is conspicuous in the lower panel of Figure 8 as a band of emission that slopes from upper left to lower right at |l| < 25◦ . ...
... them to drift inwards. The outward thrust from the bar and the frictional inward drift balance just outside rcr , and gas accumulates here. This accumulation of gas near rcr is conspicuous in the lower panel of Figure 8 as a band of emission that slopes from upper left to lower right at |l| < 25◦ . ...
LIDAR Imaging Detector Could Build `Super Road Maps` of Planets
... operational flexibility. All of these benefits will lead to lower mission cost and greater scientific productivity. Our design efforts will enable a broad range of applications, including demanding hyper-spectral imaging in the most severe radiation environments in the Solar system. They will help N ...
... operational flexibility. All of these benefits will lead to lower mission cost and greater scientific productivity. Our design efforts will enable a broad range of applications, including demanding hyper-spectral imaging in the most severe radiation environments in the Solar system. They will help N ...
The impact of X-rays on molecular cloud fragmentation and the IMF
... that sink particles are created in the compressed cloud edge much earlier than in the shielded and colder parts. A phase diagram is plotted in Fig. 3.3 that shows the decline of temperature as the density increases. The secondary band with a steep decrease in temperature at low densities is the dire ...
... that sink particles are created in the compressed cloud edge much earlier than in the shielded and colder parts. A phase diagram is plotted in Fig. 3.3 that shows the decline of temperature as the density increases. The secondary band with a steep decrease in temperature at low densities is the dire ...
THE MYSTERIOUS SICKLE OBJECT IN THE CARINA NEBULA: A
... close to the tip of the Sickle. The position of the peak of the sub-mm emission is 10h 44m 04.06s , −59◦ 33′ 35.5′′ , i.e. 10 arcseconds (or 0.1 pc) north-west of the star MJ 218 and about 3 arcseconds north-west of the apex point of the Sickle nebula. The sub-mm emission is almost point-like and on ...
... close to the tip of the Sickle. The position of the peak of the sub-mm emission is 10h 44m 04.06s , −59◦ 33′ 35.5′′ , i.e. 10 arcseconds (or 0.1 pc) north-west of the star MJ 218 and about 3 arcseconds north-west of the apex point of the Sickle nebula. The sub-mm emission is almost point-like and on ...
Period Changes of Delta Scuti Stars and Stellar Evolution
... for the longer-period evolved variables. (More exact values will be computed in a later section of this paper.) Such period changes should be observable. There have been several comparisons between theoretical and observed period changes. The careful compilation by Percy et al. (1980) led to inconcl ...
... for the longer-period evolved variables. (More exact values will be computed in a later section of this paper.) Such period changes should be observable. There have been several comparisons between theoretical and observed period changes. The careful compilation by Percy et al. (1980) led to inconcl ...
Chapter 3 (Lectures 7
... Michel Aurière and a cast of thousands of eager MuSiCoS observers have recently shown conclusively that the suite of chemical peculiarities associated with magnetic Ap stars are invariably the signature of a magnetic field (Aurière et al. 2007). They did this by selecting a sample of 28 stars in w ...
... Michel Aurière and a cast of thousands of eager MuSiCoS observers have recently shown conclusively that the suite of chemical peculiarities associated with magnetic Ap stars are invariably the signature of a magnetic field (Aurière et al. 2007). They did this by selecting a sample of 28 stars in w ...
Rapid Rotation of Low-Mass Red Giants Using APOKASC: A
... & Reiners 2011), and declare all giants rotating faster than this rate to be ’rapid rotators’. While this is a conservative approach to selecting interaction products, a single value does not allow identification of all stars in a sample that have been spun up by unusual evolution, because low-mass ...
... & Reiners 2011), and declare all giants rotating faster than this rate to be ’rapid rotators’. While this is a conservative approach to selecting interaction products, a single value does not allow identification of all stars in a sample that have been spun up by unusual evolution, because low-mass ...
THE DISRUPTION OF STELLAR CLUSTERS CONTAINING
... is part of the collapsing core, we add its mass to a growing central point mass and remove it from the simulation. This central point mass is then used only during the calculation of the cluster gravitational potential. We determine whether a star is part of the collapsing core by monitoring its orb ...
... is part of the collapsing core, we add its mass to a growing central point mass and remove it from the simulation. This central point mass is then used only during the calculation of the cluster gravitational potential. We determine whether a star is part of the collapsing core by monitoring its orb ...
The synthesis of organic and inorganic compounds in evolved stars
... giant phase. The element carbon is created by helium-burning (the triple-a process), first through core burning and later through shell burning above an electron-degenerate carbon-oxygen core. For massive (more than ten solar masses, .10 M() stars, direct nuclear burning continues with the productio ...
... giant phase. The element carbon is created by helium-burning (the triple-a process), first through core burning and later through shell burning above an electron-degenerate carbon-oxygen core. For massive (more than ten solar masses, .10 M() stars, direct nuclear burning continues with the productio ...
Spiral Galaxies: Density Waves
... • Thus there are regions of slightly higher density than their surroundings. The higher density means higher gravity. • Objects (such as a gas cloud) will be attracted to these regions and will drift towards them. ...
... • Thus there are regions of slightly higher density than their surroundings. The higher density means higher gravity. • Objects (such as a gas cloud) will be attracted to these regions and will drift towards them. ...
A detached white dwarf/M dwarf binary with an
... to the exact mass because of the form of the mass-radius relation, although it could be up to a factor of 2 smaller if the star is oversized for its mass, with the maximum size set by the Roche lobe. A further (K~ - K?-vv )/2c sin2 i = 0.1 km S-1 comes from the difference in transverse Doppler shift ...
... to the exact mass because of the form of the mass-radius relation, although it could be up to a factor of 2 smaller if the star is oversized for its mass, with the maximum size set by the Roche lobe. A further (K~ - K?-vv )/2c sin2 i = 0.1 km S-1 comes from the difference in transverse Doppler shift ...
Spin-Driven Changes in Neutron Star Magnetic Fields
... expected in a spinning-down neutron star whenever spin-down expels enough flux from the stellar core into the equatorial regions of the lower crust. Although this sort of event should occur less than once a millenium for a Vela-like pulsar, it should happen every few decades in a 104 year old pulsar ...
... expected in a spinning-down neutron star whenever spin-down expels enough flux from the stellar core into the equatorial regions of the lower crust. Although this sort of event should occur less than once a millenium for a Vela-like pulsar, it should happen every few decades in a 104 year old pulsar ...
Unit 5B PowerPoint
... device (copper and iron) thermostat (n.) measures and maintains temperature thermonuclear (adj.): related to fusion, atomic power ...
... device (copper and iron) thermostat (n.) measures and maintains temperature thermonuclear (adj.): related to fusion, atomic power ...
Hajime Togashi - International Workshop on Neutrino Physics and
... Figure 3 | Neutron star mass–radius diagram. The plot shows non-rotating mass versus physical radius for several typical EOSs27: blue, nucleons; pink, nucleons plus exotic matter; green, strange quark matter. The horizontal bands show the observational constraint from our J1614-2230 mass measurement ...
... Figure 3 | Neutron star mass–radius diagram. The plot shows non-rotating mass versus physical radius for several typical EOSs27: blue, nucleons; pink, nucleons plus exotic matter; green, strange quark matter. The horizontal bands show the observational constraint from our J1614-2230 mass measurement ...
15. Our Star - UC Berkeley Astronomy w
... • Sun’s Core becomes pure helium! • No Hydrogen burning possible. • The Helium core begins to collapse. – H shell (around Helium) heats up and H fusion begins there. – Outer layers of the Sun expand. – The Sun enters red-giant phase of its life. ...
... • Sun’s Core becomes pure helium! • No Hydrogen burning possible. • The Helium core begins to collapse. – H shell (around Helium) heats up and H fusion begins there. – Outer layers of the Sun expand. – The Sun enters red-giant phase of its life. ...
IAC_L4_halo
... For example, simulations by Abadi et al (2003) suggest that some of the thin disk stars of spirals did not form in situ but was accreted from satellites. The simulation includes gas, star formation, stars and DM. 60% of the thick disk comes from debris of accreted satellites. 90% of thick disk stars ...
... For example, simulations by Abadi et al (2003) suggest that some of the thin disk stars of spirals did not form in situ but was accreted from satellites. The simulation includes gas, star formation, stars and DM. 60% of the thick disk comes from debris of accreted satellites. 90% of thick disk stars ...
1Lec_1 - The University of Texas at Dallas
... This is the first part of a two-semester lecture sequence of introductory biology. There is a co-requisite workshop, BIO 2111. All students enrolled in BIO 2311 must also enroll in a BIO 2111 workshop[1]. The grade for BIO 2111 will be determined by attendance and scores on homework and occasional q ...
... This is the first part of a two-semester lecture sequence of introductory biology. There is a co-requisite workshop, BIO 2111. All students enrolled in BIO 2311 must also enroll in a BIO 2111 workshop[1]. The grade for BIO 2111 will be determined by attendance and scores on homework and occasional q ...
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... are s5ll significant uncertain5es in X-‐ray radia5ve transfer (porosity; resonance scatering) that require further explora5on • Even a limited sample has a big impact on the field because of the large syste ...
... are s5ll significant uncertain5es in X-‐ray radia5ve transfer (porosity; resonance scatering) that require further explora5on • Even a limited sample has a big impact on the field because of the large syste ...
The age structure of the Milky Way`s halo
... on the ages of the stellar populations in the halo of the Milky Way based on the colours of a class of stars known as field blue horizontal-branch (BHB) stars19. Originally identified because of their distinctive position in the colour-magnitude diagrams of globular clusters, BHB stars are less mass ...
... on the ages of the stellar populations in the halo of the Milky Way based on the colours of a class of stars known as field blue horizontal-branch (BHB) stars19. Originally identified because of their distinctive position in the colour-magnitude diagrams of globular clusters, BHB stars are less mass ...
Word - Department of Physics - Hong Kong University of Science
... To correct this situation, we have initialized the velocities of the particles of the red giant to be due to the translational motion of the centre of mass of the red giant, plus the rotational motion with respect to the centre of mass of the red giant too. The angular velocity of the rotational mo ...
... To correct this situation, we have initialized the velocities of the particles of the red giant to be due to the translational motion of the centre of mass of the red giant, plus the rotational motion with respect to the centre of mass of the red giant too. The angular velocity of the rotational mo ...
Chemical composition of halo and disk stars with
... by fitting Gaussians to the lines. Since only rather weak lines were included, this gives a higher accuracy than area integration, which is more affected by blends in the outer parts of the lines. Altogether 13 halo stars and 16 disk stars were observed. Most of them have magnitudes between mV = 9 a ...
... by fitting Gaussians to the lines. Since only rather weak lines were included, this gives a higher accuracy than area integration, which is more affected by blends in the outer parts of the lines. Altogether 13 halo stars and 16 disk stars were observed. Most of them have magnitudes between mV = 9 a ...
Cluster formation in molecular clouds – I. Stellar populations, star
... fixed output that does not change with time. As an example, the luminosity of a cluster can be determined from its mass via an averaged IMF (Murray, Quataert & Thompson 2010). This simplified approach misses key aspects of the star formation process. As an attempt to bridge the gap between these two ...
... fixed output that does not change with time. As an example, the luminosity of a cluster can be determined from its mass via an averaged IMF (Murray, Quataert & Thompson 2010). This simplified approach misses key aspects of the star formation process. As an attempt to bridge the gap between these two ...
Main sequence
In astronomy, the main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell. Stars on this band are known as main-sequence stars or ""dwarf"" stars.After a star has formed, it generates thermal energy in the dense core region through the nuclear fusion of hydrogen atoms into helium. During this stage of the star's lifetime, it is located along the main sequence at a position determined primarily by its mass, but also based upon its chemical composition and other factors. All main-sequence stars are in hydrostatic equilibrium, where outward thermal pressure from the hot core is balanced by the inward pressure of gravitational collapse from the overlying layers. The strong dependence of the rate of energy generation in the core on the temperature and pressure helps to sustain this balance. Energy generated at the core makes its way to the surface and is radiated away at the photosphere. The energy is carried by either radiation or convection, with the latter occurring in regions with steeper temperature gradients, higher opacity or both.The main sequence is sometimes divided into upper and lower parts, based on the dominant process that a star uses to generate energy. Stars below about 1.5 times the mass of the Sun (or 1.5 solar masses (M☉)) primarily fuse hydrogen atoms together in a series of stages to form helium, a sequence called the proton–proton chain. Above this mass, in the upper main sequence, the nuclear fusion process mainly uses atoms of carbon, nitrogen and oxygen as intermediaries in the CNO cycle that produces helium from hydrogen atoms. Main-sequence stars with more than two solar masses undergo convection in their core regions, which acts to stir up the newly created helium and maintain the proportion of fuel needed for fusion to occur. Below this mass, stars have cores that are entirely radiative with convective zones near the surface. With decreasing stellar mass, the proportion of the star forming a convective envelope steadily increases, whereas main-sequence stars below 0.4 M☉ undergo convection throughout their mass. When core convection does not occur, a helium-rich core develops surrounded by an outer layer of hydrogen.In general, the more massive a star is, the shorter its lifespan on the main sequence. After the hydrogen fuel at the core has been consumed, the star evolves away from the main sequence on the HR diagram. The behavior of a star now depends on its mass, with stars below 0.23 M☉ becoming white dwarfs directly, whereas stars with up to ten solar masses pass through a red giant stage. More massive stars can explode as a supernova, or collapse directly into a black hole.