how dry is the brown dwarf desert? quantifying the
... from other Doppler searches found in the literature. Our sample selection is illustrated in Figure 1 and detailed in Table 1 (complete list in the electronic version only) for stars closer than 25 pc and Figure 2 for stars closer than 50 pc. Most Doppler survey target stars come from the Hipparcos c ...
... from other Doppler searches found in the literature. Our sample selection is illustrated in Figure 1 and detailed in Table 1 (complete list in the electronic version only) for stars closer than 25 pc and Figure 2 for stars closer than 50 pc. Most Doppler survey target stars come from the Hipparcos c ...
banff04
... higher accretion rates and mass outflow rates (e.g. Pudritz 1985). • Disk photo-evaporation could create a low-velocity disk outflow (e.g. Hollenbach et al. 1994; Yorke & Welz 1996). • Radiation pressure higher for dusty gas (e.g. Wolfire & Cassinelli 1987), may contribute to flow acceleration and a ...
... higher accretion rates and mass outflow rates (e.g. Pudritz 1985). • Disk photo-evaporation could create a low-velocity disk outflow (e.g. Hollenbach et al. 1994; Yorke & Welz 1996). • Radiation pressure higher for dusty gas (e.g. Wolfire & Cassinelli 1987), may contribute to flow acceleration and a ...
Thermohaline mixing and the photospheric composition of low
... the square of the (unknown) aspect ratio α (length/width) of fluid elements. Unfortunately, this leads to a strong uncertainty in its value, since the linear theory does not reliably estimate the maximum length of salt fingers relative to their diameter. Laboratory experiments that simulate oceanic ...
... the square of the (unknown) aspect ratio α (length/width) of fluid elements. Unfortunately, this leads to a strong uncertainty in its value, since the linear theory does not reliably estimate the maximum length of salt fingers relative to their diameter. Laboratory experiments that simulate oceanic ...
STRUCTURE AND EVOLUTION OF WHITE DWARFS S. 0. Kepler1
... do not know the timescale for a white dwarf to undergo a spectral type change, and only G 104-27 shows any evidence for it (Kidder et al. 1992). It may not be coincidence that the PNN also divide into about 70 % hydrogen rich and 30 % helium rich members, which might indicate a separate channel for ...
... do not know the timescale for a white dwarf to undergo a spectral type change, and only G 104-27 shows any evidence for it (Kidder et al. 1992). It may not be coincidence that the PNN also divide into about 70 % hydrogen rich and 30 % helium rich members, which might indicate a separate channel for ...
View/Open - University of Hertfordshire
... Albada et al. [1985] and others. These studies show that the kinematics of objects, under Newtonian gravitational theory, cannot be fully accounted for by the mass of observed luminous matter in the universe, and additional matter must be added. While it is unlikely that all baryonic matter has been ...
... Albada et al. [1985] and others. These studies show that the kinematics of objects, under Newtonian gravitational theory, cannot be fully accounted for by the mass of observed luminous matter in the universe, and additional matter must be added. While it is unlikely that all baryonic matter has been ...
A" Light," Centrally-Concentrated Milky Way Halo?
... the tracer properties, Galactic mass measurements suffer from the well-known mass-anisotropy-density degeneracy. The unknown properties and low number of tracers, the uncertainties as to whether some satellites are bound or unbound, and the problematic extrapolations from the inner halo to the viria ...
... the tracer properties, Galactic mass measurements suffer from the well-known mass-anisotropy-density degeneracy. The unknown properties and low number of tracers, the uncertainties as to whether some satellites are bound or unbound, and the problematic extrapolations from the inner halo to the viria ...
Accreting millisecond X-ray pulsars: a search for pulsed radio
... supernova event, which occurs when a massive star runs out of nuclear fuel in its core at the end of its life. A typical neutron star has a mass between 1 M⊙ – 2.1 M⊙ , with a corresponding radius range of 8 – 15 km and then a resulting central density of 1014 −1015 g/cm3 (Lattimer & Prakash 2007). ...
... supernova event, which occurs when a massive star runs out of nuclear fuel in its core at the end of its life. A typical neutron star has a mass between 1 M⊙ – 2.1 M⊙ , with a corresponding radius range of 8 – 15 km and then a resulting central density of 1014 −1015 g/cm3 (Lattimer & Prakash 2007). ...
New Evidence for Mass-Loss from δ Cephei from H i 21
... Cepheids. While IR excesses were not directly detected, ruling out the presence of a large amount of warm (∼500 K) dust in close proximity to the stars, the Spitzer images revealed extended emission around several targets (Marengo et al. 2010a; Barmby et al. 2011). Perhaps the most intriguing was th ...
... Cepheids. While IR excesses were not directly detected, ruling out the presence of a large amount of warm (∼500 K) dust in close proximity to the stars, the Spitzer images revealed extended emission around several targets (Marengo et al. 2010a; Barmby et al. 2011). Perhaps the most intriguing was th ...
On the origin of lopsidedness in galaxies as determined
... Eymeren et al. 2011b). Despite the ubiquity of m = 1 distortions, how they arise remains unresolved, even though various mechanisms have been suggested (see Jog & Combes 2009 for a review of the field). As usual, the scenarios can be divided into a “nature” category, for example, one in which the lo ...
... Eymeren et al. 2011b). Despite the ubiquity of m = 1 distortions, how they arise remains unresolved, even though various mechanisms have been suggested (see Jog & Combes 2009 for a review of the field). As usual, the scenarios can be divided into a “nature” category, for example, one in which the lo ...
THE ORIGIN AND EVOLUTION OF PLANETARY NEBULAE
... Herschel (1791). However, no further progress was made for another century. Hubble (1922), using data obtained with the Mount Wilson 60- and 100-in. telescopes, found a correlation between the magnitude of the central star and the size of the nebula. He therefore argued that the emission-line spectr ...
... Herschel (1791). However, no further progress was made for another century. Hubble (1922), using data obtained with the Mount Wilson 60- and 100-in. telescopes, found a correlation between the magnitude of the central star and the size of the nebula. He therefore argued that the emission-line spectr ...
The VLT LEGA-C Spectroscopic Survey: The Physics of Galaxies at
... derstand the star formation history, and stellar velocity dispersions are a crucial element in quantifying the dynamical scaling relations such the Faber & Jackson (1976) relation, the Tully & Fisher (1977), and the fundamental plane (Djorgovski & Davis 1987; Dressler et al. 1987), the evolution of ...
... derstand the star formation history, and stellar velocity dispersions are a crucial element in quantifying the dynamical scaling relations such the Faber & Jackson (1976) relation, the Tully & Fisher (1977), and the fundamental plane (Djorgovski & Davis 1987; Dressler et al. 1987), the evolution of ...
ON THE ORIGIN OF THE SALPETER SLOPE FOR THE INITIAL
... logarithmic Salpeter slope Γ = 1.35 in clusters is then the aggregate slope for all the star-forming clumps contributing to an individual cluster, and it is steeper than the intrinsic slope within individual clumps because the smallest star-forming clumps contributing to any given cluster are unable ...
... logarithmic Salpeter slope Γ = 1.35 in clusters is then the aggregate slope for all the star-forming clumps contributing to an individual cluster, and it is steeper than the intrinsic slope within individual clumps because the smallest star-forming clumps contributing to any given cluster are unable ...
The X-ray/radio and UV luminosity expected from symbiotic systems
... Context. Symbiotic systems (i.e. a white dwarf + red giant star, WD + RG), which experience mass loss and form circumstellar material (CSM), have been suggested as being a possible progenitor system of type Ia supernovae (SNe Ia). After a supernova explosion, the supernova ejecta may interact with t ...
... Context. Symbiotic systems (i.e. a white dwarf + red giant star, WD + RG), which experience mass loss and form circumstellar material (CSM), have been suggested as being a possible progenitor system of type Ia supernovae (SNe Ia). After a supernova explosion, the supernova ejecta may interact with t ...
Follow-up observations of extremely metal
... compositions that are close to the pristine mixture from Big Bang nucleosynthesis, polluted by one or few supernovae. Aims. Only two dozen stars with ([Fe/H]< −4) are known, and they show a wide range of abundance patterns. It is therefore important to enlarge this sample. We present the first resul ...
... compositions that are close to the pristine mixture from Big Bang nucleosynthesis, polluted by one or few supernovae. Aims. Only two dozen stars with ([Fe/H]< −4) are known, and they show a wide range of abundance patterns. It is therefore important to enlarge this sample. We present the first resul ...
the solar neighborhood. xxviii. the multiplicity fraction of nearby stars
... various color combinations and present astrometry for 19 multiple systems in our sample. Considering these results and results from several other studies, we argue that the so-called brown dwarf desert extends to binary systems with low-mass primaries and is largely independent of primary mass, mass ...
... various color combinations and present astrometry for 19 multiple systems in our sample. Considering these results and results from several other studies, we argue that the so-called brown dwarf desert extends to binary systems with low-mass primaries and is largely independent of primary mass, mass ...
Vicky Kaspi Chandra Anomalous X-ray Pulsars Fotis Gavriil
... • SGRs (5): giant flares, short bursts, spectral changes, pulse profile changes, timing anomalies… • AXPs (9): short bursts, outbursts, slow flux changes, long-lived flares, glitches… – Most recognized only since 2002 ...
... • SGRs (5): giant flares, short bursts, spectral changes, pulse profile changes, timing anomalies… • AXPs (9): short bursts, outbursts, slow flux changes, long-lived flares, glitches… – Most recognized only since 2002 ...
edmund c. stoner and the discovery of the maximum mass of white
... white dwarfs”.24 Again Chandrasekhar was able to obtain his result with great ease, because the relevant solution of the differential equation for gravitational equilibrium for the extreme relativistic equation of state of a degenerate electron, which has an exponent 4/3, corresponds to the n = 3 La ...
... white dwarfs”.24 Again Chandrasekhar was able to obtain his result with great ease, because the relevant solution of the differential equation for gravitational equilibrium for the extreme relativistic equation of state of a degenerate electron, which has an exponent 4/3, corresponds to the n = 3 La ...
The Current Status of Galaxy Formation
... dark matter is found to be excessive in barred galaxies and in dwarfs. The resolution to all of these difficulties must lie in feedback. There are various flavors of feedback that span the range of processes including reionization at very high redshift, supernova (SN) explosions, tidal stripping and ...
... dark matter is found to be excessive in barred galaxies and in dwarfs. The resolution to all of these difficulties must lie in feedback. There are various flavors of feedback that span the range of processes including reionization at very high redshift, supernova (SN) explosions, tidal stripping and ...
P-nuclei
p-Nuclei (p stands for proton-rich) are certain proton-rich, naturally occurring isotopes of some elements between selenium and mercury which cannot be produced in either s- or r-process.