New Evidence for Mass-Loss from δ Cephei from H i 21
... for neutral atomic hydrogen associated with this wind. Our VLA data reveal a spatially extended H i nebula (∼ 13′ or 1 pc across) surrounding the position of δ Cephei. The nebula has a head-tail morphology, consistent with circumstellar ejecta shaped by the interaction between a stellar wind and the ...
... for neutral atomic hydrogen associated with this wind. Our VLA data reveal a spatially extended H i nebula (∼ 13′ or 1 pc across) surrounding the position of δ Cephei. The nebula has a head-tail morphology, consistent with circumstellar ejecta shaped by the interaction between a stellar wind and the ...
starwalk2 manual en
... If your device has built-in compass tilt your device and the Star Spotter function will be activated. Star Walk™ uses the digital compass to learn which way you are looking. A live representation of what you see in the sky will appear on your display and the sky will start following your movements w ...
... If your device has built-in compass tilt your device and the Star Spotter function will be activated. Star Walk™ uses the digital compass to learn which way you are looking. A live representation of what you see in the sky will appear on your display and the sky will start following your movements w ...
The 13C(α,n)16O reaction rate. Recent estimates, new
... of nuclei lighter than 12 C, which are created during the first minutes after the Big Bang) are produced in stars. The main cause of heating, contraction and density increase in stars is the total gravitational energy of the stellar mass. Generally speaking, the larger is the mass, the higher is the ...
... of nuclei lighter than 12 C, which are created during the first minutes after the Big Bang) are produced in stars. The main cause of heating, contraction and density increase in stars is the total gravitational energy of the stellar mass. Generally speaking, the larger is the mass, the higher is the ...
The Chemical Composition of Exoplanet
... and stellar systems. Furthermore, a comparison between binary components will be made to look for any systematic differences between binary partners having planets, and those without currently known planets. Binary systems are an ideal comparison because the stars are very likely to have formed from ...
... and stellar systems. Furthermore, a comparison between binary components will be made to look for any systematic differences between binary partners having planets, and those without currently known planets. Binary systems are an ideal comparison because the stars are very likely to have formed from ...
IAC_L3_thickdisk
... Diversion to radial migration (Sellwood & Binney 2002) Stars in disk galaxies can migrate in radius under the torque of a passing transient spiral wave. Stars moving at similar angular velocity to the spiral are flipped from one near-circular orbit to another: inwards or outwards. The spiral wave m ...
... Diversion to radial migration (Sellwood & Binney 2002) Stars in disk galaxies can migrate in radius under the torque of a passing transient spiral wave. Stars moving at similar angular velocity to the spiral are flipped from one near-circular orbit to another: inwards or outwards. The spiral wave m ...
Lecture 2. Isolated Neutron Stars – I.
... At high masses the slope is usually steeper. Note: it is initial mass function, not the present day! M Mmin ...
... At high masses the slope is usually steeper. Note: it is initial mass function, not the present day! M Mmin ...
On the possibility of a helium white dwarf donor in the presumed
... Abstract. 2S 0918–549 is a low-mass X-ray binary (LMXB) with a low optical to X-ray flux ratio. Probably it is an ultracompact binary with an orbital period shorter than 60 min. Such binaries cannot harbor hydrogen rich donor stars. As with other (sometimes confirmed) ultracompact LMXBs, 2S 0918–549 ...
... Abstract. 2S 0918–549 is a low-mass X-ray binary (LMXB) with a low optical to X-ray flux ratio. Probably it is an ultracompact binary with an orbital period shorter than 60 min. Such binaries cannot harbor hydrogen rich donor stars. As with other (sometimes confirmed) ultracompact LMXBs, 2S 0918–549 ...
Spatial distribution of electron cloud footprints
... detectors with charge-division readouts often requires optimization of the event charge footprint to achieve high spatial resolution and good image linearity. The best performance of many readout schemes is obtained when the charge cloud is spread out in the plane of the anode, so that several pitch ...
... detectors with charge-division readouts often requires optimization of the event charge footprint to achieve high spatial resolution and good image linearity. The best performance of many readout schemes is obtained when the charge cloud is spread out in the plane of the anode, so that several pitch ...
Photometric transit search for planets around cool stars from the
... their radii which can in turn provide a useful testing ground for improving stellar evolution models. Secondly, degeneracies in the models of the physical structures of Super-Earths, such as objects with very different compositions having similar masses and radii, also prevent one from exactly infer ...
... their radii which can in turn provide a useful testing ground for improving stellar evolution models. Secondly, degeneracies in the models of the physical structures of Super-Earths, such as objects with very different compositions having similar masses and radii, also prevent one from exactly infer ...
... use the time delay between a light pulse sent to an object and the return of the reflected light pulse plus the finite speed of light to measure distances. However, stars are so far away and such poor reflectors that this approach is impractical (though it is used to determine distances to planets i ...
Curtis/Shapley Debate – 1920 - Tufts Institute of Cosmology
... did not always have telescopes. Humanity didn't always know the limits of our Galaxy and the existence of other galaxies - this knowledge came only this century - what was thought previously? While it is certainly true that early civilizations had a drastically different picture of the universe, the ...
... did not always have telescopes. Humanity didn't always know the limits of our Galaxy and the existence of other galaxies - this knowledge came only this century - what was thought previously? While it is certainly true that early civilizations had a drastically different picture of the universe, the ...
The environment of high-redshift AGN OLIMPIA JUDIT FOGASY
... According to the currently accepted cosmological model, the Λ Cold Dark Matter model (ΛCDM), structure formation started from primordial density fluctuations followed by gravitational collapse of dark matter, leading to the formation of dark matter haloes. As the virial equilibrium is reached in the ...
... According to the currently accepted cosmological model, the Λ Cold Dark Matter model (ΛCDM), structure formation started from primordial density fluctuations followed by gravitational collapse of dark matter, leading to the formation of dark matter haloes. As the virial equilibrium is reached in the ...
models for low-mass x-ray binaries in the elliptical
... 1037 ergs s1), pointing to a different LMXB formation mechanism in GCs. The natural question that arises is whether (1) all LMXBs were formed in GCs through dynamical interactions and some eventually escaped or some GCs dissolved in the field, or (2) field LMXBs were born in situ through binary evo ...
... 1037 ergs s1), pointing to a different LMXB formation mechanism in GCs. The natural question that arises is whether (1) all LMXBs were formed in GCs through dynamical interactions and some eventually escaped or some GCs dissolved in the field, or (2) field LMXBs were born in situ through binary evo ...
REVIEW Early star-forming galaxies and the reionization of the Universe
... produced by star-forming galaxies can be modelled and, assuming that some fraction can escape the galaxies, the average volume fraction of hydrogen ionized by these photons (QH II) can be calculated from the star formation rate density. The history of star formation is further constrained by its tim ...
... produced by star-forming galaxies can be modelled and, assuming that some fraction can escape the galaxies, the average volume fraction of hydrogen ionized by these photons (QH II) can be calculated from the star formation rate density. The history of star formation is further constrained by its tim ...
ppt
... most objects, the dispersion of 10point averages is much higher than that which is expected for white noise, especially for brighter magnitudes. The dotted line shows the expected dispersion of the 10-point means according to the discussion in this paper, with an amplitude of σr= 3.6 mmag for the re ...
... most objects, the dispersion of 10point averages is much higher than that which is expected for white noise, especially for brighter magnitudes. The dotted line shows the expected dispersion of the 10-point means according to the discussion in this paper, with an amplitude of σr= 3.6 mmag for the re ...
arXiv 2011 Feroci
... are also observed during type I X-ray bursts, which are mostly the result of thermally unstable helium ignition in the accreted envelope of a neutron star. This generates a thermonuclear explosion that is observed as an X-ray burst with a rapid rise (∼1 s) followed by a slower decay (∼10–100 s). X-r ...
... are also observed during type I X-ray bursts, which are mostly the result of thermally unstable helium ignition in the accreted envelope of a neutron star. This generates a thermonuclear explosion that is observed as an X-ray burst with a rapid rise (∼1 s) followed by a slower decay (∼10–100 s). X-r ...
eng_gw150914
... interactions, the registration of which there is only a question of their experimental detection. There have, of course, and the reverse processes - processes of formation, condensation, absorption of baryonic matter, which we consider in other articles. The case of the merger of black holes ...
... interactions, the registration of which there is only a question of their experimental detection. There have, of course, and the reverse processes - processes of formation, condensation, absorption of baryonic matter, which we consider in other articles. The case of the merger of black holes ...
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.