Dusty AGN Tori
... density annular ring dust with inner radius a, outer radius b and height h (15). The dust extinction curve is that of Fig. 10. The central luminosity is assumed to be a power-law spectrum The four model parameters are: the inner aspect ratio a/h, the radial and vertical Thomson depths of the torus,τ ...
... density annular ring dust with inner radius a, outer radius b and height h (15). The dust extinction curve is that of Fig. 10. The central luminosity is assumed to be a power-law spectrum The four model parameters are: the inner aspect ratio a/h, the radial and vertical Thomson depths of the torus,τ ...
Planet formation around M-dwarfs: the moving snow line and super
... 2–3 AU, and 1–2M⊕ planets at 3–4 AU. If we simply adapt the collisional history of Earth formation to a planetesimal disk around a 0.25M star, mergers of ∼10 oligarchs should yield planets with masses ∼1–2M⊕ at 1 AU and ∼3–5M⊕ at 2.5 AU. To consider whether oligarchs can merge into superEarths on r ...
... 2–3 AU, and 1–2M⊕ planets at 3–4 AU. If we simply adapt the collisional history of Earth formation to a planetesimal disk around a 0.25M star, mergers of ∼10 oligarchs should yield planets with masses ∼1–2M⊕ at 1 AU and ∼3–5M⊕ at 2.5 AU. To consider whether oligarchs can merge into superEarths on r ...
FIVE NEW TRANSITS OF THE SUPER
... determine the best-fitting parameter values and confidence intervals. This algorithm delivers an estimate of the a posteriori joint probability distribution for all of the parameters (see Holman et al. 2006 or Winn et al. 2007 for more details). For each parameter we took the mode of the distributio ...
... determine the best-fitting parameter values and confidence intervals. This algorithm delivers an estimate of the a posteriori joint probability distribution for all of the parameters (see Holman et al. 2006 or Winn et al. 2007 for more details). For each parameter we took the mode of the distributio ...
Document
... observations of M dwarfs to determine flare rates • I am creating model galaxy simulations to predict flare rates on a Galactic scale that includes spectral type and activity level. We can ‘observe’ this model to predict what LSST will see. ...
... observations of M dwarfs to determine flare rates • I am creating model galaxy simulations to predict flare rates on a Galactic scale that includes spectral type and activity level. We can ‘observe’ this model to predict what LSST will see. ...
The First Stars in the Universe - Scientific American
... and Abraham Loeb of Harvard, one of us (Bromm) devised theoretical models of such stars with masses between 100 and 1,000 solar masses. The models showed that the stars had surface temperatures of about 100,000 kelvins—about 17 times higher than the sun’s surface temperature. Therefore, the first st ...
... and Abraham Loeb of Harvard, one of us (Bromm) devised theoretical models of such stars with masses between 100 and 1,000 solar masses. The models showed that the stars had surface temperatures of about 100,000 kelvins—about 17 times higher than the sun’s surface temperature. Therefore, the first st ...
Spectral modeling of nebular-phase supernovae Anders Jerkstrand Department of Astronomy
... where Z is the proton number, q is the charge unit, and kB is Boltzmann’s constant. For hydrogen (Z = 1), we obtain T ∼ 1010 K. At the beginning of ...
... where Z is the proton number, q is the charge unit, and kB is Boltzmann’s constant. For hydrogen (Z = 1), we obtain T ∼ 1010 K. At the beginning of ...
double shell–burning
... Role of Mass • A star’s mass determines its entire life story because it determines its core temperature. • High-mass stars with > 8MSun have short lives, eventually becoming hot enough to make iron, and end in supernova explosions. • Low-mass stars with < 2MSun have long lives, ...
... Role of Mass • A star’s mass determines its entire life story because it determines its core temperature. • High-mass stars with > 8MSun have short lives, eventually becoming hot enough to make iron, and end in supernova explosions. • Low-mass stars with < 2MSun have long lives, ...
Solar flux variation of the electron temperature morning
... plasma drift velocities further decrease the local ion density, which increases Te. As the ion density builds up after sunrise, Te decreases to daytime values that are reached at about 09 LT. The neutral density and the electron‐neutral cooling rate also build up after sunrise but it has a smaller e ...
... plasma drift velocities further decrease the local ion density, which increases Te. As the ion density builds up after sunrise, Te decreases to daytime values that are reached at about 09 LT. The neutral density and the electron‐neutral cooling rate also build up after sunrise but it has a smaller e ...
Modified r-matrix analysis of the 19F(p,a)16O HOES reaction
... is a key isotope in astrophysics as it can be used to probe AGB star mixing phenomena and nucleosynthesis. But its production is still uncertain! In AGB stars, the largest observed fluorine overabundances cannot be explained with standard AGB models. A possible lack of proper accounting for the cont ...
... is a key isotope in astrophysics as it can be used to probe AGB star mixing phenomena and nucleosynthesis. But its production is still uncertain! In AGB stars, the largest observed fluorine overabundances cannot be explained with standard AGB models. A possible lack of proper accounting for the cont ...
Highligh in Physics 2005
... FU Orionis objects are a small class of young stellar objects undergoing periods of enhanced disk accretion activity (outbursts). While T Tauri stars usually have rather low accretion rates (of the order of 10-8 M/yr), during the outburst the accretion rate can reach a few times 10-4 M/yr. Even if ...
... FU Orionis objects are a small class of young stellar objects undergoing periods of enhanced disk accretion activity (outbursts). While T Tauri stars usually have rather low accretion rates (of the order of 10-8 M/yr), during the outburst the accretion rate can reach a few times 10-4 M/yr. Even if ...
Pre-main sequence evolution
... What are T Tauri & Herbig Ae/Be stars? • T Tauri stars are low-mass stars with discs • Herbig Ae/Be stars are intermediate-mass stars with discs • in the Hertzsprung-Russel-Diagram (HRD), both are located above the main sequence, in the region of pre-main sequence evolution Pre-main sequence: • mai ...
... What are T Tauri & Herbig Ae/Be stars? • T Tauri stars are low-mass stars with discs • Herbig Ae/Be stars are intermediate-mass stars with discs • in the Hertzsprung-Russel-Diagram (HRD), both are located above the main sequence, in the region of pre-main sequence evolution Pre-main sequence: • mai ...
The solution of the radiative transfer equation in axial symmetry
... thick regions it’s possible to calculate using a method which uses the diffusion approximation [10]. Both of these methods are inappropriate for stellar atmospheres. The classical way for calculating a solution to this equation in more dimensions is the long characteristic method [2]. This method fu ...
... thick regions it’s possible to calculate using a method which uses the diffusion approximation [10]. Both of these methods are inappropriate for stellar atmospheres. The classical way for calculating a solution to this equation in more dimensions is the long characteristic method [2]. This method fu ...
Lecture 2. Thermal evolution and surface emission of
... The total thermal energy of a nonsuperfluid neutron star is estimated as UT ~ 1048 T29 erg. The heat capacity of an npe neutron star core with strongly superfluid neutrons and protons is determined by the electrons, which are not superfluid, and it is ~20 times lower than for a neutron star with a n ...
... The total thermal energy of a nonsuperfluid neutron star is estimated as UT ~ 1048 T29 erg. The heat capacity of an npe neutron star core with strongly superfluid neutrons and protons is determined by the electrons, which are not superfluid, and it is ~20 times lower than for a neutron star with a n ...
Surface temperatures at the nearside of the Moon as a
... variability and the change in the global mean surface temperature. However, model simulations show that the observed change in total solar irradiance has a much smaller impact on the observed temperature change than does the anthropogenic greenhouse effect (Bender et al., 2006; Hansen et al., 2002; L ...
... variability and the change in the global mean surface temperature. However, model simulations show that the observed change in total solar irradiance has a much smaller impact on the observed temperature change than does the anthropogenic greenhouse effect (Bender et al., 2006; Hansen et al., 2002; L ...
point-like
... Goal: a deeper understanding of a particular issue/problem analyzed in class, or a totally new AGN-related topic we did not have time to talk about Either a literature search or original data analysis (using data from public archives) Submit an outline for pre-approval by November 1 Your paper (< 20 ...
... Goal: a deeper understanding of a particular issue/problem analyzed in class, or a totally new AGN-related topic we did not have time to talk about Either a literature search or original data analysis (using data from public archives) Submit an outline for pre-approval by November 1 Your paper (< 20 ...
STELLAR SPECTRA A. Basic Line Formation
... division on the basis of spectral line appearances; – Hertzsprung (1908) and Russell (1913) independently plot a diagram of stellar absolute magnitude against spectral type (Figure 1). It shows that stars occupy sharply defined locations in this parameter space; – Cecilia Payne (1925): demonstration ...
... division on the basis of spectral line appearances; – Hertzsprung (1908) and Russell (1913) independently plot a diagram of stellar absolute magnitude against spectral type (Figure 1). It shows that stars occupy sharply defined locations in this parameter space; – Cecilia Payne (1925): demonstration ...
