From Supernovae to Planets - Astronomical Society of the Pacific
... The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a partnership of NASA and the German Aerospace Center (DLR), consisting of an extensively modified Boeing 747SP aircraft carrying a reflecting telescope with an effective diameter of 2.5 meters (100 inches). Based at NASA's Armstrong Fl ...
... The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a partnership of NASA and the German Aerospace Center (DLR), consisting of an extensively modified Boeing 747SP aircraft carrying a reflecting telescope with an effective diameter of 2.5 meters (100 inches). Based at NASA's Armstrong Fl ...
The Constant-Sound-Speed parameterization of the quark matter EoS
... cores. Since little is known about the quark matter equation of state, we perform a model-independent study of the form of the mass-radius relation for hybrid stars, making only some generic assumptions about the quark matter EoS. The CSS parameterization of the EoS has three parameters: (1) at what ...
... cores. Since little is known about the quark matter equation of state, we perform a model-independent study of the form of the mass-radius relation for hybrid stars, making only some generic assumptions about the quark matter EoS. The CSS parameterization of the EoS has three parameters: (1) at what ...
Document
... Oppenheimer’s theory of neutron stars Neutron stars were first proposed to exist, and to cause supernovae by their formation, by Zwicky and Baade (1934). First calculations of their sizes: Landau (1938). Neutron stars are analogous to white dwarfs, but the calculations are much more difficult, si ...
... Oppenheimer’s theory of neutron stars Neutron stars were first proposed to exist, and to cause supernovae by their formation, by Zwicky and Baade (1934). First calculations of their sizes: Landau (1938). Neutron stars are analogous to white dwarfs, but the calculations are much more difficult, si ...
Incredible Shrinking Stars
... they age, because the energy of rotation is dissipated in creating the 'lighthouse' beams. Eventually, the pulse becomes very weak. In addition, we don't even expect to see fresh, young pulsars because, in order for us to see the pulsed beams, they must be pointed at us! There's no reason why all pu ...
... they age, because the energy of rotation is dissipated in creating the 'lighthouse' beams. Eventually, the pulse becomes very weak. In addition, we don't even expect to see fresh, young pulsars because, in order for us to see the pulsed beams, they must be pointed at us! There's no reason why all pu ...
Slide sem título - Instituto de Física / UFRJ
... (9.2X1011 g/cm3) to 5X103 MeV/fm3 (9.2X1015 g/cm3). We can see in fig. 1 that both the total mass and radius of the stars are increased by the presence of charge. Fig. 2 shows how much charge these stars can have. Table 1 shows these results for the maximum mass configuration [4]. ...
... (9.2X1011 g/cm3) to 5X103 MeV/fm3 (9.2X1015 g/cm3). We can see in fig. 1 that both the total mass and radius of the stars are increased by the presence of charge. Fig. 2 shows how much charge these stars can have. Table 1 shows these results for the maximum mass configuration [4]. ...
15. Our Star - UC Berkeley Astronomy w
... • The mass of the iron (Fe) core increases - Iron can’t burn: - No nuclear reactions: no energy production! – Gravity overwhelms the gas pressure – Electrons are squeezed into protons neutrons ...
... • The mass of the iron (Fe) core increases - Iron can’t burn: - No nuclear reactions: no energy production! – Gravity overwhelms the gas pressure – Electrons are squeezed into protons neutrons ...
Wilderness House Literary Review Volume 8 Number 2
... however, it’s made whenever a star explodes and independent fragments of atom nuclei are fuzed together. It is created in the last act of a stellar super-nova. An act that may only take a second to complete before the entire star explodes. Such stars are visible as the brightest star in the sky and ...
... however, it’s made whenever a star explodes and independent fragments of atom nuclei are fuzed together. It is created in the last act of a stellar super-nova. An act that may only take a second to complete before the entire star explodes. Such stars are visible as the brightest star in the sky and ...
C, N, O abundances and carbon isotope ratios in evolved stars of
... (2002) performed an abundance analysis of carbon for a sample of 90 F- and G-type main-sequence disk stars using C i and [C i] lines and found [C/Fe] to be about solar at solar metallicity. Roughly solar carbon abundances were found by Gustafsson et al. (1999), who analysed a sample of 80 late-F and ...
... (2002) performed an abundance analysis of carbon for a sample of 90 F- and G-type main-sequence disk stars using C i and [C i] lines and found [C/Fe] to be about solar at solar metallicity. Roughly solar carbon abundances were found by Gustafsson et al. (1999), who analysed a sample of 80 late-F and ...
Variable Star Observation
... • There are two different types of variable stars and four main classes. • Types of variable stars: ...
... • There are two different types of variable stars and four main classes. • Types of variable stars: ...
Astronomy 112: The Physics of Stars Class 8 Notes: Nuclear
... Which of these chains is most important depends on the local density, temperature, and chemical composition. Obviously pp II and pp III are more likely when there is more 42 He around, since they require it. In Sun, pp I is 69% of all reactions, pp II is 31%, and pp III is 0.1%. 2. Energetics and Ra ...
... Which of these chains is most important depends on the local density, temperature, and chemical composition. Obviously pp II and pp III are more likely when there is more 42 He around, since they require it. In Sun, pp I is 69% of all reactions, pp II is 31%, and pp III is 0.1%. 2. Energetics and Ra ...
HST Observations of the
... knowing how bright they appeared and relating them to other Cepheid stars which were used as standard candles, we can estimate the distance to the galaxies. calculated estimates have the nearest galaxies within the HDF approximately ...
... knowing how bright they appeared and relating them to other Cepheid stars which were used as standard candles, we can estimate the distance to the galaxies. calculated estimates have the nearest galaxies within the HDF approximately ...
The Chemical Composition of Carbon-Rich, Very Metal
... hypothesis for the formation of these stars is that of Fujimoto, Ikeda & Iben (2000), who suggested that production of large carbon and nitrogen excesses may follow from extensive mixing in low-mass (M . 1M⊙ ), very metal-poor stars at their helium core flash at the end of the giant branch, or durin ...
... hypothesis for the formation of these stars is that of Fujimoto, Ikeda & Iben (2000), who suggested that production of large carbon and nitrogen excesses may follow from extensive mixing in low-mass (M . 1M⊙ ), very metal-poor stars at their helium core flash at the end of the giant branch, or durin ...
Cepheid variable stars
... Pulsating stars are a type of variable star in which brightness variations are caused by changes in the area and temperature of the star’s surface layers. Recent evidence suggests that all stars pulsate (if we measure them carefully enough), although the presence of concentrated populations of pulsa ...
... Pulsating stars are a type of variable star in which brightness variations are caused by changes in the area and temperature of the star’s surface layers. Recent evidence suggests that all stars pulsate (if we measure them carefully enough), although the presence of concentrated populations of pulsa ...
Astronomy Chapter 16 – The Milky Way Galaxy A. Main Ideas 1
... ⇒ Interstellar gas is the material from which stars form, and it is the repository (storage place) of matter blown off dying stars 5. Motion of Stars and Gas in the Milky Way Although all stars within the Milky Way move around its center, the paths followed by stars in the disk and halo are very dif ...
... ⇒ Interstellar gas is the material from which stars form, and it is the repository (storage place) of matter blown off dying stars 5. Motion of Stars and Gas in the Milky Way Although all stars within the Milky Way move around its center, the paths followed by stars in the disk and halo are very dif ...
Similarity Renormalization Groups (SRG) for nuclear forces
... sidered degree of freedom. The expansion begins The unitarity of the SRG evolution is therefore with momentum independent contact interactions only preserved if all these higher order forces are and pion exchanges in leading order (LO). Three- considerd. In practise however, most calculations body f ...
... sidered degree of freedom. The expansion begins The unitarity of the SRG evolution is therefore with momentum independent contact interactions only preserved if all these higher order forces are and pion exchanges in leading order (LO). Three- considerd. In practise however, most calculations body f ...
Spectroscopy PPT
... Dark-line spectrum – a continuous spectrum with dark lines where light has been absorbed. (absorption spectrum) Helium absorption spectrum ...
... Dark-line spectrum – a continuous spectrum with dark lines where light has been absorbed. (absorption spectrum) Helium absorption spectrum ...
Lecture 12
... There is an upper limit to the mass of a white dwarf - we do not see WDs with masses > 1.4 M We will see in next lectures what the implications of this are for other phenomena in the Universe. It actually led to the discovery of dark energy! The collapse of massive stars produces two types of remna ...
... There is an upper limit to the mass of a white dwarf - we do not see WDs with masses > 1.4 M We will see in next lectures what the implications of this are for other phenomena in the Universe. It actually led to the discovery of dark energy! The collapse of massive stars produces two types of remna ...
hydrogen deficient stars and related objects
... stars, something which has puzzled us from the very beginning, is how extreme helium stars are formed and how a star of one solar mass may get rid of all its original hydrogen. A few rivalling hypotheses are known but up to now none of them are convincing. The aim of the meeting was to bring us clos ...
... stars, something which has puzzled us from the very beginning, is how extreme helium stars are formed and how a star of one solar mass may get rid of all its original hydrogen. A few rivalling hypotheses are known but up to now none of them are convincing. The aim of the meeting was to bring us clos ...
New challenges in Nuclear Structure
... instrumentation and detection equipment will be required to carry on the various programmes. The project AGATA, for a 4-array of highly segmented Ge detectors for g-ray detection and tracking, will benefit research programmes in the various facilities in Europe. NuPECC gives full support for the co ...
... instrumentation and detection equipment will be required to carry on the various programmes. The project AGATA, for a 4-array of highly segmented Ge detectors for g-ray detection and tracking, will benefit research programmes in the various facilities in Europe. NuPECC gives full support for the co ...
Presentazione di PowerPoint
... Beyond a few thousand Schwarzschild radii from the central SMBH, but within the sphere of influence, the motion of stars and gas is predominantly Keplerian (relativistic effects are minimal), with a component due to the combined gravitational potential of stars, dust, gas, dark matter, and anything ...
... Beyond a few thousand Schwarzschild radii from the central SMBH, but within the sphere of influence, the motion of stars and gas is predominantly Keplerian (relativistic effects are minimal), with a component due to the combined gravitational potential of stars, dust, gas, dark matter, and anything ...
AMUSE-Virgo on the survival of super
... - 84 new targets with Chandra ACIS-S (454 ksec) + 16 archival - 57 new targets with Spitzer MIPS (9.5 hr) + 43 archival - HST ACS archival data (100 orbits) - VLA, in progress (with D. Axon) ...
... - 84 new targets with Chandra ACIS-S (454 ksec) + 16 archival - 57 new targets with Spitzer MIPS (9.5 hr) + 43 archival - HST ACS archival data (100 orbits) - VLA, in progress (with D. Axon) ...
![Cosmic variance in [O/Fe] in the Galactic disk](http://s1.studyres.com/store/data/014331057_1-996ec6eddf93071c5e835624d4620c7e-300x300.png)
chemical abundances for a-and f-type supergiant stars
... The process of chemical evolution in the Galaxy can be understood from the study of its massive stars. These objects in their rapid evolution undergo changes through the process of nucleosynthesis and return their chemical elements to the interstellar medium by stellar winds and supernova events. Th ...
... The process of chemical evolution in the Galaxy can be understood from the study of its massive stars. These objects in their rapid evolution undergo changes through the process of nucleosynthesis and return their chemical elements to the interstellar medium by stellar winds and supernova events. Th ...
Nucleosynthesis
Nucleosynthesis is the process that creates new atomic nuclei from pre-existing nucleons, primarily protons and neutrons. The first nuclei were formed about three minutes after the Big Bang, through the process called Big Bang nucleosynthesis. It was then that hydrogen and helium formed to become the content of the first stars, and this primeval process is responsible for the present hydrogen/helium ratio of the cosmos.With the formation of stars, heavier nuclei were created from hydrogen and helium by stellar nucleosynthesis, a process that continues today. Some of these elements, particularly those lighter than iron, continue to be delivered to the interstellar medium when low mass stars eject their outer envelope before they collapse to form white dwarfs. The remains of their ejected mass form the planetary nebulae observable throughout our galaxy.Supernova nucleosynthesis within exploding stars by fusing carbon and oxygen is responsible for the abundances of elements between magnesium (atomic number 12) and nickel (atomic number 28). Supernova nucleosynthesis is also thought to be responsible for the creation of rarer elements heavier than iron and nickel, in the last few seconds of a type II supernova event. The synthesis of these heavier elements absorbs energy (endothermic) as they are created, from the energy produced during the supernova explosion. Some of those elements are created from the absorption of multiple neutrons (the R process) in the period of a few seconds during the explosion. The elements formed in supernovas include the heaviest elements known, such as the long-lived elements uranium and thorium.Cosmic ray spallation, caused when cosmic rays impact the interstellar medium and fragment larger atomic species, is a significant source of the lighter nuclei, particularly 3He, 9Be and 10,11B, that are not created by stellar nucleosynthesis.In addition to the fusion processes responsible for the growing abundances of elements in the universe, a few minor natural processes continue to produce very small numbers of new nuclides on Earth. These nuclides contribute little to their abundances, but may account for the presence of specific new nuclei. These nuclides are produced via radiogenesis (decay) of long-lived, heavy, primordial radionuclides such as uranium and thorium. Cosmic ray bombardment of elements on Earth also contribute to the presence of rare, short-lived atomic species called cosmogenic nuclides.