Chemical Composition of Planetary Nebulae: The Galaxy and the
... the SMC extends to even lower metallicities, namely (O) 7.0. Taking into account the Galactic and MC nebulae by Stasińska et al. [18], these results are confirmed and extended, especially at lower metallicities, (O) < 8.0, for which their sample is richer than ours. Correlations Involving N An a ...
... the SMC extends to even lower metallicities, namely (O) 7.0. Taking into account the Galactic and MC nebulae by Stasińska et al. [18], these results are confirmed and extended, especially at lower metallicities, (O) < 8.0, for which their sample is richer than ours. Correlations Involving N An a ...
The Evryscope: the first full-sky gigapixel-scale telescope Nicholas Law
... Habitable zone of M-dwarfs Asteroids around white dwarfs Confirmation of long-period TESS single-transit detections ...
... Habitable zone of M-dwarfs Asteroids around white dwarfs Confirmation of long-period TESS single-transit detections ...
The Sun as an X-Ray Star. III. Flares
... than expected, therefore leading to very coarse loop lengths overestimates. A useful tool to identify the presence of such a prolonged heating is the Ñare density-temperature diagram : the longer the heating decay (compared to the free cooling loop decay time ; Serio et al. 1991), the smaller is the ...
... than expected, therefore leading to very coarse loop lengths overestimates. A useful tool to identify the presence of such a prolonged heating is the Ñare density-temperature diagram : the longer the heating decay (compared to the free cooling loop decay time ; Serio et al. 1991), the smaller is the ...
Extrasolar Cosmochemistry
... atmosphere. These stars are typically the radius of Earth and slowly cool from an initial outer temperature above 100,000 K. Once the effective temperature of the atmosphere falls below 20,000 K, radiative levitation—the process of supporting an element in the atmosphere by the upward flow of radiati ...
... atmosphere. These stars are typically the radius of Earth and slowly cool from an initial outer temperature above 100,000 K. Once the effective temperature of the atmosphere falls below 20,000 K, radiative levitation—the process of supporting an element in the atmosphere by the upward flow of radiati ...
white dwarfs and the age of the universe
... of energy: latent heat and sedimentation. In the case of Coulomb plasmas, the latent heat is small, of the order of kB Ts per nuclei, where kB is the Boltzmann constant and Ts is the temperature of solidification. Its contribution to the total luminosity is between ∼ 5 and 10% [18]. During the cryst ...
... of energy: latent heat and sedimentation. In the case of Coulomb plasmas, the latent heat is small, of the order of kB Ts per nuclei, where kB is the Boltzmann constant and Ts is the temperature of solidification. Its contribution to the total luminosity is between ∼ 5 and 10% [18]. During the cryst ...
The Formation of Primordial Luminous Objects - SLAC
... (i) Free streaming: the dark matter particles are in motion, and since they are believed to interact only through gravity, they freely propagate from overdense to underdense regions, wiping out the density perturbations. However, at any given cosmic time t, this will affect only wavelengths smaller ...
... (i) Free streaming: the dark matter particles are in motion, and since they are believed to interact only through gravity, they freely propagate from overdense to underdense regions, wiping out the density perturbations. However, at any given cosmic time t, this will affect only wavelengths smaller ...
Broggini
... Neutron flux, mainly from (a,n): 2.92 10-6 cm-2s-1 (0-1 keV), 0.86 10-6 cm-2s-1 (> 1 keV), 3 orders of magnitude reduction Gamma rays: only 1 order of magnitude reduction, but with thick shield about 5 orders of magnitude in the region of natural radioactivity and 4-5 orders above 3.2 MeV without an ...
... Neutron flux, mainly from (a,n): 2.92 10-6 cm-2s-1 (0-1 keV), 0.86 10-6 cm-2s-1 (> 1 keV), 3 orders of magnitude reduction Gamma rays: only 1 order of magnitude reduction, but with thick shield about 5 orders of magnitude in the region of natural radioactivity and 4-5 orders above 3.2 MeV without an ...
The Stellar Population And Origin Of The Mysterious K.V. Getman
... made 30 years ago by Williams et al. (1977) who suggested that a large expanding highlatitude interstellar shell could have traversed CG12 7-19 Myr ago. Produced by one or more supernova explosions from a still-unidentified association, the encounter would have drawn out the 10 pc-long tail and trig ...
... made 30 years ago by Williams et al. (1977) who suggested that a large expanding highlatitude interstellar shell could have traversed CG12 7-19 Myr ago. Produced by one or more supernova explosions from a still-unidentified association, the encounter would have drawn out the 10 pc-long tail and trig ...
The fuelling of local supermassive black holes
... Heating by SNIa’s is likely also secularly evolving (for the most recent modeling see Greggio 2005, A&A): QuickTime™ and a TIFF (LZW) decompressor are needed to see this picture. ...
... Heating by SNIa’s is likely also secularly evolving (for the most recent modeling see Greggio 2005, A&A): QuickTime™ and a TIFF (LZW) decompressor are needed to see this picture. ...
their evolution, nucleosynthesis and dusty end
... For Intermediate Mass Stars, the temperature at the bottom of the convective envelope is high enough (T>4e7 K) to allow proton captures: ...
... For Intermediate Mass Stars, the temperature at the bottom of the convective envelope is high enough (T>4e7 K) to allow proton captures: ...
Chapter 9 Post-main sequence evolution through helium burning
... D is spent in the thick shell burning phase at relatively small radii and log T eff > 4.05. The phase of expansion from log T eff ≈ 4.05 to point D at log T eff ≈ 3.7 occurs on the Kelvin-Helmholtz timescale and takes only a few times 105 yrs. A substantial fraction of the energy generated by shell ...
... D is spent in the thick shell burning phase at relatively small radii and log T eff > 4.05. The phase of expansion from log T eff ≈ 4.05 to point D at log T eff ≈ 3.7 occurs on the Kelvin-Helmholtz timescale and takes only a few times 105 yrs. A substantial fraction of the energy generated by shell ...
Word - The Open University
... You will appreciate from Figure 2 that the rest of this course will necessarily refer to incredibly small times after the Big Bang (notice how far along the graph 1 second appears). Many important processes took place when the Universe was significantly less than 1 s old, when the energy available f ...
... You will appreciate from Figure 2 that the rest of this course will necessarily refer to incredibly small times after the Big Bang (notice how far along the graph 1 second appears). Many important processes took place when the Universe was significantly less than 1 s old, when the energy available f ...
3011800000631
... dim isolated thermally emitting neutron stars (DINs) have rotation periods all in the same narrow range P = 3−12 s, giving rotation rates Ω ~ O(1)? As Psaltis and Miller (2002) have shown, dipole spindown (braking index n = 3) or spindown with any other power law index in the range n = 2−4, can prod ...
... dim isolated thermally emitting neutron stars (DINs) have rotation periods all in the same narrow range P = 3−12 s, giving rotation rates Ω ~ O(1)? As Psaltis and Miller (2002) have shown, dipole spindown (braking index n = 3) or spindown with any other power law index in the range n = 2−4, can prod ...
dark matter?
... WIMPs) must be high in order for these particles to meet up and destroy each other. This typically happens within more massive objects. A WIMP near the Sun or Earth could collide with an ordinary particle’s nucleus. (This is similar to what happens within detector material.) The WIMP will lose energ ...
... WIMPs) must be high in order for these particles to meet up and destroy each other. This typically happens within more massive objects. A WIMP near the Sun or Earth could collide with an ordinary particle’s nucleus. (This is similar to what happens within detector material.) The WIMP will lose energ ...
ASTRONOMY AND ASTROPHYSICS Barium and europium
... halo stars are of the r-process origin. Much observational efforts were invested in testing this idea. For extremely metalpoor stars with metallicities [Fe/H] ≤ −2.4 McWilliam (1998) has derived an average [Eu/Ba] = 0.69, consistent with pure rprocess nucleosynthesis provided that the data of Arland ...
... halo stars are of the r-process origin. Much observational efforts were invested in testing this idea. For extremely metalpoor stars with metallicities [Fe/H] ≤ −2.4 McWilliam (1998) has derived an average [Eu/Ba] = 0.69, consistent with pure rprocess nucleosynthesis provided that the data of Arland ...
2. The Universe Is Expanding and Evolving
... the surface of last scattering, which occurred 380,000 years after the Big Bang. It’s like a distant wallpaper covering the entire sky behind all the stars and galaxies. This is important, as it means that we can clearly see any structures (irregularities in the distribution of matter) that may be i ...
... the surface of last scattering, which occurred 380,000 years after the Big Bang. It’s like a distant wallpaper covering the entire sky behind all the stars and galaxies. This is important, as it means that we can clearly see any structures (irregularities in the distribution of matter) that may be i ...
Magnetars origin and progenitors with enhanced rotation'
... Magnetars origin and progenitors with enhanced rotation S.B. Popov, M.E. Prokhorov (Sternberg Astronomical Institute) ...
... Magnetars origin and progenitors with enhanced rotation S.B. Popov, M.E. Prokhorov (Sternberg Astronomical Institute) ...
THE FINAL FATE OF STARS THAT IGNITE NEON AND OXYGEN
... is not enough to quench the propagation of the carbon flame in super-AGB stars, and the flame successfully reaches the center of the star. Furthermore, Denissenkov and collaborators have tested the resilience of the carbon-burning flame when assuming a convective boundary mixing characterized by an ...
... is not enough to quench the propagation of the carbon flame in super-AGB stars, and the flame successfully reaches the center of the star. Furthermore, Denissenkov and collaborators have tested the resilience of the carbon-burning flame when assuming a convective boundary mixing characterized by an ...
GDR-PH-QCD, IPNO 7/XII/2012
... • The residual energy turns into kinetic energy of the motion with relative velocity • The strong chromo-EM field leads to an effective loss of color. Fermi statistics: identical quarks are repulsed. The remaining quark of different flavor is attracted to one of the identical quarks, creating a comp ...
... • The residual energy turns into kinetic energy of the motion with relative velocity • The strong chromo-EM field leads to an effective loss of color. Fermi statistics: identical quarks are repulsed. The remaining quark of different flavor is attracted to one of the identical quarks, creating a comp ...
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.