The double-pulsar PSR J0737−3039A/B
... of about 2.58 M giving a maximum mass for the pulsar of about 1.34 M and a minimum mass for the companion of 1.24 M . The maximum mass for the pulsar perfectly agrees with the other measurements of neutron star masses (Thorsett & Chakrabarthy 1999), while the mass of the companion is only slightl ...
... of about 2.58 M giving a maximum mass for the pulsar of about 1.34 M and a minimum mass for the companion of 1.24 M . The maximum mass for the pulsar perfectly agrees with the other measurements of neutron star masses (Thorsett & Chakrabarthy 1999), while the mass of the companion is only slightl ...
WHITE DWARFS AS A SOURCE OF CONSTRAINTS ON EXOTIC …
... Modern astrophysics is a great success of standard physical theories in understanding stellar structure and evolution Stars serves as a source of constraints on non standard ideas Some of these constraints turn out to be more stringent than laboratory ones First idea: weakly interacting partic ...
... Modern astrophysics is a great success of standard physical theories in understanding stellar structure and evolution Stars serves as a source of constraints on non standard ideas Some of these constraints turn out to be more stringent than laboratory ones First idea: weakly interacting partic ...
Astronomy 250 - University of Victoria
... Every measured quantity will always have an associated uncertainy. Errors can occur, for example, because of the limitations of the measuring device, because of systematic offsets (see below), because of legitimate dispersions in the data, etc. Example: Suppose you are trying to measure the brightne ...
... Every measured quantity will always have an associated uncertainy. Errors can occur, for example, because of the limitations of the measuring device, because of systematic offsets (see below), because of legitimate dispersions in the data, etc. Example: Suppose you are trying to measure the brightne ...
Foretellings of Ragnar\" ok: World-engulfing Asymptotic Giants and
... These thermal pulses responsible for the modulations in the stellar radius are also the drivers of the mass loss through the generation of shocks in the stellar envelope that allow the nucleation of dust grains (see, e.g., Bowen 1988, and references therein). As grains nucleate and grow they experie ...
... These thermal pulses responsible for the modulations in the stellar radius are also the drivers of the mass loss through the generation of shocks in the stellar envelope that allow the nucleation of dust grains (see, e.g., Bowen 1988, and references therein). As grains nucleate and grow they experie ...
Extrasolar Kuiper Belt Dust Disks
... At any particular age, observations show a great diversity of debris disks surrounding similar type stars [see section 3.1 and Andrews and Williams (2005)]. This may be due to the following factors that can influence the disks at different stages during their evolution: (1) different initial masses ...
... At any particular age, observations show a great diversity of debris disks surrounding similar type stars [see section 3.1 and Andrews and Williams (2005)]. This may be due to the following factors that can influence the disks at different stages during their evolution: (1) different initial masses ...
An introduction to photometry and photometric measurements Henry
... electrons counted in an electronic detector) to physically meaningful quantities like flux and flux density ...
... electrons counted in an electronic detector) to physically meaningful quantities like flux and flux density ...
FOE 2017 Poster Contributions - College of Science | Oregon State
... core-collapse of a massive star or from the thermonuclear detonation of a white dwarf, is a central problem of modern astrophysics. For a handful of SNe, we have been able to identify the progenitor from pre-explosion images (e.g., Gerke et al., 2015; Adams et al., 2016); however, for supernova remn ...
... core-collapse of a massive star or from the thermonuclear detonation of a white dwarf, is a central problem of modern astrophysics. For a handful of SNe, we have been able to identify the progenitor from pre-explosion images (e.g., Gerke et al., 2015; Adams et al., 2016); however, for supernova remn ...
Luminosity and Mass Functions of Galaxies
... Need stellar mass-to-light ratios to convert luminosity function to mass function. (Total mass can be found dynamically.) Bell et al. (2003) develop conversion from luminosity and color to M/L. Create a grid of stellar populations with range of metalicities and star-formation histories. Compute colo ...
... Need stellar mass-to-light ratios to convert luminosity function to mass function. (Total mass can be found dynamically.) Bell et al. (2003) develop conversion from luminosity and color to M/L. Create a grid of stellar populations with range of metalicities and star-formation histories. Compute colo ...
X-ray activity cycle on the active ultra
... gratings. These two reflection-grating spectrometers (RGS) provide high spectral resolution (E/ΔE ≈ 200–800) in the energy range 0.35–2.5 keV. Useful data were obtained from the EPIC and the RGS detectors (see Table 1 for a detailed account). AB Dor A, which is a very bright target with many emissio ...
... gratings. These two reflection-grating spectrometers (RGS) provide high spectral resolution (E/ΔE ≈ 200–800) in the energy range 0.35–2.5 keV. Useful data were obtained from the EPIC and the RGS detectors (see Table 1 for a detailed account). AB Dor A, which is a very bright target with many emissio ...
Star formation in luminous quasar host galaxies at z = 1–2 ⋆
... explore the host galaxies. We fit the images with simple axisymmetric galaxy models, including a point source, in order to separate nuclear and host-galaxy emission. We successfully model all of the host galaxies, with luminosities stable to within 0.3 mag. Combining with our earlier Near Infrared C ...
... explore the host galaxies. We fit the images with simple axisymmetric galaxy models, including a point source, in order to separate nuclear and host-galaxy emission. We successfully model all of the host galaxies, with luminosities stable to within 0.3 mag. Combining with our earlier Near Infrared C ...
Planetary Nebula
... Scientists believe the hourglass shape is produced by the expansion of a fast stellar wind within a slowly expanding cloud which is more dense near its equator than near its poles. The hot star which has been thought to eject and illuminate the nebula, and therefore expected to lie at its center of ...
... Scientists believe the hourglass shape is produced by the expansion of a fast stellar wind within a slowly expanding cloud which is more dense near its equator than near its poles. The hot star which has been thought to eject and illuminate the nebula, and therefore expected to lie at its center of ...
S-process in extremely metal-poor, low-mass stars
... star formation. Simulations by Greif et al. (2011) seem to indicate that Pop. III stars can be formed in multiple systems with a flat protostellar mass function (M ∼ 0.1−10 M ). Moreover, the recent discovery of an EMP star with a metallicity of [Fe/H] = −4.89 and no enhancement in CNO elements (Ca ...
... star formation. Simulations by Greif et al. (2011) seem to indicate that Pop. III stars can be formed in multiple systems with a flat protostellar mass function (M ∼ 0.1−10 M ). Moreover, the recent discovery of an EMP star with a metallicity of [Fe/H] = −4.89 and no enhancement in CNO elements (Ca ...
Progenitor neutron stars of the lightest and heaviest millisecond
... effect of a slow Roche-lobe detachment phase, which could be relevant for PSR J0751+1807, would make the lower mass limit even lower. A realistic theory for core-collapse supernovæ should account for this wide range of mass. Key words. equation of state – stars: neutron – accretion, accretion disks – ...
... effect of a slow Roche-lobe detachment phase, which could be relevant for PSR J0751+1807, would make the lower mass limit even lower. A realistic theory for core-collapse supernovæ should account for this wide range of mass. Key words. equation of state – stars: neutron – accretion, accretion disks – ...
Kepler-63b: A Giant Planet in a Polar Orbit around a Young Sun
... to the trajectory of the planet across the stellar disk; when the planet transits again, the spot is likely to have remained on the transit chord and a spot-crossing event will occur at a later phase of the transit. In contrast, the rotation of a highly oblique star would carry the spot away from th ...
... to the trajectory of the planet across the stellar disk; when the planet transits again, the spot is likely to have remained on the transit chord and a spot-crossing event will occur at a later phase of the transit. In contrast, the rotation of a highly oblique star would carry the spot away from th ...
Conditions for water ice lines and Mars-mass
... Context. The first detection of a moon around an extrasolar planet (an “exomoon”) might be feasible with NASA’s Kepler or ESA’s upcoming PLATO space telescopes or with the future ground-based European Extremely Large Telescope. To guide observers and to use observational resources most efficiently, ...
... Context. The first detection of a moon around an extrasolar planet (an “exomoon”) might be feasible with NASA’s Kepler or ESA’s upcoming PLATO space telescopes or with the future ground-based European Extremely Large Telescope. To guide observers and to use observational resources most efficiently, ...
shell properties
... Based on observations made with the Canada-France-Hawaii telescope, operated by CNRS, NRCC and UH, and on dearchived observations made with the NASA/ESA Hubble Space Telescope, operated by AURA Inc., under NASA contract NAS5-26555 ...
... Based on observations made with the Canada-France-Hawaii telescope, operated by CNRS, NRCC and UH, and on dearchived observations made with the NASA/ESA Hubble Space Telescope, operated by AURA Inc., under NASA contract NAS5-26555 ...
Star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as ""stellar nurseries"" or ""star-forming regions"", collapse to form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.