The SOPHIE search for northern extrasolar planets
... We present high-precision radial-velocity measurements of three solar-type stars: HD 13908, HD 159243, and HIP 91258. The observations were made with the SOPHIE spectrograph at the 1.93 m telescope of the Observatoire de Haute-Provence (France). They show that these three bright stars host exoplanet ...
... We present high-precision radial-velocity measurements of three solar-type stars: HD 13908, HD 159243, and HIP 91258. The observations were made with the SOPHIE spectrograph at the 1.93 m telescope of the Observatoire de Haute-Provence (France). They show that these three bright stars host exoplanet ...
Synergies between E-ELT and space instrumentation for
... Young stars (<5 108 yrs) Nearby stars (<20 pc) Many giant planets (both young and old) Tens of Neptune-like planets A few rocky planets La ricerca dei pianeti extrasolari in Italia Roma, Nov. 5-7 2014 ...
... Young stars (<5 108 yrs) Nearby stars (<20 pc) Many giant planets (both young and old) Tens of Neptune-like planets A few rocky planets La ricerca dei pianeti extrasolari in Italia Roma, Nov. 5-7 2014 ...
AMUSE-Virgo AGN Multi-wavelength Survey
... AMUSE, the team: E. Gallo, T. Treu, J.-H. Woo, J. Jacob, R. Antonucci, ...
... AMUSE, the team: E. Gallo, T. Treu, J.-H. Woo, J. Jacob, R. Antonucci, ...
Galactic astroarchaeology: reconstructing the bulge history by
... solar vicinity (∼–1.0). For spiral and irregular instead, the Fe enrichment by core collapse SNe is much less, due to the milder SFR, and the [Fe/H] is still low when type Ia SNe start appearing. Thus the change in slope in irregulars occurs at [Fe/H] ≤–2.0 (see Matteucci 2001). Years later, McWilli ...
... solar vicinity (∼–1.0). For spiral and irregular instead, the Fe enrichment by core collapse SNe is much less, due to the milder SFR, and the [Fe/H] is still low when type Ia SNe start appearing. Thus the change in slope in irregulars occurs at [Fe/H] ≤–2.0 (see Matteucci 2001). Years later, McWilli ...
Ascertaining the Core Collapse Supernova Mechanism: An
... explosion is not obtained in spherical symmetry demonstrates that multidimensional effects are required for explosion, which is an important conclusion that frames all subsequent work in two and three dimensions differently than if the opposite were true. Similarly, two-dimensional models have now a ...
... explosion is not obtained in spherical symmetry demonstrates that multidimensional effects are required for explosion, which is an important conclusion that frames all subsequent work in two and three dimensions differently than if the opposite were true. Similarly, two-dimensional models have now a ...
ellc: A fast, flexible light curve model for detached eclipsing binary
... the thermal structure of its atmosphere. As a result, the emergent spectrum can be very different to that of the incident radiation, e.g., ultraviolet photons from the companion can be absorbed and re-emitted as emission lines at optical wavelengths. The change in thermal structure also changes the ...
... the thermal structure of its atmosphere. As a result, the emergent spectrum can be very different to that of the incident radiation, e.g., ultraviolet photons from the companion can be absorbed and re-emitted as emission lines at optical wavelengths. The change in thermal structure also changes the ...
Distance determination for RAVE stars using stellar models
... ated. The right panel Fig. 1 shows isochrones of similar chemical composition and can be compared to the stellar tracks shown on the left panel. All stars on the 0.01 Gyr isochrone are still on the main sequence. For older isochrones we can clearly see the main sequence turnoff points, the point at ...
... ated. The right panel Fig. 1 shows isochrones of similar chemical composition and can be compared to the stellar tracks shown on the left panel. All stars on the 0.01 Gyr isochrone are still on the main sequence. For older isochrones we can clearly see the main sequence turnoff points, the point at ...
- UCL Discovery
... Pelupessy, van der Werf & Icke 2004). The thermal energy of the feedback particles is calculated with the SPH scheme with radiative cooling and additional heating from stellar wind, SNe II and SNe Ia. Eight out of the 19 feedback particles spend no time being stars and immediately become SNe II feed ...
... Pelupessy, van der Werf & Icke 2004). The thermal energy of the feedback particles is calculated with the SPH scheme with radiative cooling and additional heating from stellar wind, SNe II and SNe Ia. Eight out of the 19 feedback particles spend no time being stars and immediately become SNe II feed ...
THE KEPLER CLUSTER STUDY: STELLAR ROTATION IN NGC 6811
... process, attempts are made to remove signals in the data from pointing drifts, focus changes, and thermal variations. As described in the Kepler Data Release Notes (Van Cleve et al. 2010), the pipeline is still under development and is primarily intended to optimize the search for planetary transits ...
... process, attempts are made to remove signals in the data from pointing drifts, focus changes, and thermal variations. As described in the Kepler Data Release Notes (Van Cleve et al. 2010), the pipeline is still under development and is primarily intended to optimize the search for planetary transits ...
PDF only - at www.arxiv.org.
... points, MinPts, in its ε-neighborhood (the circle of radius ε, centered on a data point) required to be considered as a cluster. The algorithm starts from an arbitrary data point in the data set. For this point, if the number of other data points in its ε-neighborhood is less than MinPts, the point ...
... points, MinPts, in its ε-neighborhood (the circle of radius ε, centered on a data point) required to be considered as a cluster. The algorithm starts from an arbitrary data point in the data set. For this point, if the number of other data points in its ε-neighborhood is less than MinPts, the point ...
Which of the following is not a characteristic of the stars of the disk
... Please indicate the best answer to the following questions on the answer sheet provided. 1. Which of the following is not a characteristic of the stars of the disk component of our galaxy? a. circular orbits, b. randomly inclined orbits, c. higher metal abundance d. young stars, 2. The mass of a sin ...
... Please indicate the best answer to the following questions on the answer sheet provided. 1. Which of the following is not a characteristic of the stars of the disk component of our galaxy? a. circular orbits, b. randomly inclined orbits, c. higher metal abundance d. young stars, 2. The mass of a sin ...
The Eight Parts of Speech:
... SUR means over. The surface of the sea is over the rest; a surrealist is an artist who depicts things beyond ordinary reality; a surfeit is an excess! ...
... SUR means over. The surface of the sea is over the rest; a surrealist is an artist who depicts things beyond ordinary reality; a surfeit is an excess! ...
3. Solar System Formation and Early Evolution
... stellar cluster the Sun was born: our star is about 50 times older than the oldest open clusters. But the issue is fundamental for planet formation in general and for the origin of the solar system in particular, because of the short time evolution of the circumstellar disks around young stars (see ...
... stellar cluster the Sun was born: our star is about 50 times older than the oldest open clusters. But the issue is fundamental for planet formation in general and for the origin of the solar system in particular, because of the short time evolution of the circumstellar disks around young stars (see ...
REVIEWS 18 years of science with the Hubble Space Telescope Julianne J. Dalcanton
... stellar clusters. The HST is yielding surprises even for more ordinary stars. For most of the past century, astronomers believed that the simplest collections of stars could be found in globular clusters, which are dense, gravitationally bound groups of ,104–106 stars. The stars in globular clusters ...
... stellar clusters. The HST is yielding surprises even for more ordinary stars. For most of the past century, astronomers believed that the simplest collections of stars could be found in globular clusters, which are dense, gravitationally bound groups of ,104–106 stars. The stars in globular clusters ...
The half-light radius distribution of LBGs and their
... • The predicted stellar mass function of LBGs is obtained; • The predicted correlation length of LBGs, which can be tested by Spitzer, is also obtained ...
... • The predicted stellar mass function of LBGs is obtained; • The predicted correlation length of LBGs, which can be tested by Spitzer, is also obtained ...
SN 2011dh and the progenitors of Type IIb supernovae Mattias Ergon
... situation is quite different, and a furious struggle between gravity and pressure is coming to its end. In the oxygen-magnesium core the temperature exceeds a billion Kelvin, oxygen burning will soon ignite, and in the six years that follows the temperature will continue to rise, the nuclear burning ...
... situation is quite different, and a furious struggle between gravity and pressure is coming to its end. In the oxygen-magnesium core the temperature exceeds a billion Kelvin, oxygen burning will soon ignite, and in the six years that follows the temperature will continue to rise, the nuclear burning ...
ppt
... • An open cluster is a group of up to a few thousand stars that were formed from the same giant molecular cloud, and are still gravitationally bound to each other • Open clusters are found only in spiral and irregular galaxies, in which active star formation is occurring. • The Pleiades is an open c ...
... • An open cluster is a group of up to a few thousand stars that were formed from the same giant molecular cloud, and are still gravitationally bound to each other • Open clusters are found only in spiral and irregular galaxies, in which active star formation is occurring. • The Pleiades is an open c ...
December - Weasner
... send that boat to the celestial breaker’s yard, on the grounds that it was too unwieldy. Despite being thought of as a far-southern group, I was able to hunt out a variety of targets from Northern England ! M47 was a large grouping of some 25 brighter stars which showed up well despite the Full Moon ...
... send that boat to the celestial breaker’s yard, on the grounds that it was too unwieldy. Despite being thought of as a far-southern group, I was able to hunt out a variety of targets from Northern England ! M47 was a large grouping of some 25 brighter stars which showed up well despite the Full Moon ...
Stellar evolution
Stellar evolution is the process by which a star changes during its lifetime. Depending on the mass of the star, this lifetime ranges from a few million years for the most massive to trillions of years for the least massive, which is considerably longer than the age of the universe. The table shows the lifetimes of stars as a function of their masses. All stars are born from collapsing clouds of gas and dust, often called nebulae or molecular clouds. Over the course of millions of years, these protostars settle down into a state of equilibrium, becoming what is known as a main-sequence star.Nuclear fusion powers a star for most of its life. Initially the energy is generated by the fusion of hydrogen atoms at the core of the main-sequence star. Later, as the preponderance of atoms at the core becomes helium, stars like the Sun begin to fuse hydrogen along a spherical shell surrounding the core. This process causes the star to gradually grow in size, passing through the subgiant stage until it reaches the red giant phase. Stars with at least half the mass of the Sun can also begin to generate energy through the fusion of helium at their core, whereas more-massive stars can fuse heavier elements along a series of concentric shells. Once a star like the Sun has exhausted its nuclear fuel, its core collapses into a dense white dwarf and the outer layers are expelled as a planetary nebula. Stars with around ten or more times the mass of the Sun can explode in a supernova as their inert iron cores collapse into an extremely dense neutron star or black hole. Although the universe is not old enough for any of the smallest red dwarfs to have reached the end of their lives, stellar models suggest they will slowly become brighter and hotter before running out of hydrogen fuel and becoming low-mass white dwarfs.Stellar evolution is not studied by observing the life of a single star, as most stellar changes occur too slowly to be detected, even over many centuries. Instead, astrophysicists come to understand how stars evolve by observing numerous stars at various points in their lifetime, and by simulating stellar structure using computer models.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.