Overview and first year observation of CALET Gamma ray Burst
... That is collisions between each ejecta which have a different velocity in a relativistic jet cause the internal shock (Rees and Meszaros, 1994 ). The shock accelerated electrons radiate X-rays or gamma-rays due to the synchrotron radiation. The spectra of the prompt emissions show a broad energy dis ...
... That is collisions between each ejecta which have a different velocity in a relativistic jet cause the internal shock (Rees and Meszaros, 1994 ). The shock accelerated electrons radiate X-rays or gamma-rays due to the synchrotron radiation. The spectra of the prompt emissions show a broad energy dis ...
The Role of Radioactive Isotopes in Astrophysics
... neutrons; indeed, it is today their major source in burning shells of massive stars, although that insight is usually attributed to later emphasis by others. It is unfortunate that Hoyle did not put to paper the equation he envisioned and described. Had he done so, clearer scientific visibility of h ...
... neutrons; indeed, it is today their major source in burning shells of massive stars, although that insight is usually attributed to later emphasis by others. It is unfortunate that Hoyle did not put to paper the equation he envisioned and described. Had he done so, clearer scientific visibility of h ...
High-precision abundances of elements in solar twin stars: Trends
... tra of FGK stars, a sample of solar twins was selected to have parameters that agree with those of the Sun within ±100 K in T eff , ±0.15 dex in log g, and ±0.10 dex in [Fe/H]. Listed in Table 1, 21 of these stars have HARPS spectra with S /N ≥ 600 after combination of spectra available in the ESO S ...
... tra of FGK stars, a sample of solar twins was selected to have parameters that agree with those of the Sun within ±100 K in T eff , ±0.15 dex in log g, and ±0.10 dex in [Fe/H]. Listed in Table 1, 21 of these stars have HARPS spectra with S /N ≥ 600 after combination of spectra available in the ESO S ...
Stardust--Snapshots of Stars
... technique on the NanoSIMS that expands on automated methods developed in the early 2000s to study presolar grains . Preserved in primitive meteorites, presolar grains are literally stardust that formed in ancient stellar outflows and ejecta from supernova explosions, and became part of the molecular ...
... technique on the NanoSIMS that expands on automated methods developed in the early 2000s to study presolar grains . Preserved in primitive meteorites, presolar grains are literally stardust that formed in ancient stellar outflows and ejecta from supernova explosions, and became part of the molecular ...
Barium and europium abundances in cool dwarf stars and
... Ba abundance consist of 88% and 12%, respectively, according to Cameron (1982), 87% and 13% according to Käppeler et al. (1989), and 81% and 19% according to the most recent data of Arlandini et al. (1999). The solar europium mostly originated from the r-process: 91% according to Cameron (1982) and ...
... Ba abundance consist of 88% and 12%, respectively, according to Cameron (1982), 87% and 13% according to Käppeler et al. (1989), and 81% and 19% according to the most recent data of Arlandini et al. (1999). The solar europium mostly originated from the r-process: 91% according to Cameron (1982) and ...
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 ...
Chemical composition of cosmic dust in the solar vicinity
... - comparison with Orion dust: graphite minor species ► C in PAHs - homogeneity over hundreds of parsecs: highly efficient mixing Multiple phases IS Dust (ISM-SPP) Garching– 15.09.2016 ...
... - comparison with Orion dust: graphite minor species ► C in PAHs - homogeneity over hundreds of parsecs: highly efficient mixing Multiple phases IS Dust (ISM-SPP) Garching– 15.09.2016 ...
16. Composition of solar system small bodies Pierre Vernazza Aix
... characteristics as high temperature meteorites (type 4 to 6 OCs) that were thermally metamorphosed in their interiors, these exposed interiors being a likely consequence of impacts by small asteroids (D<10km) in the early solar system (Ciesla et al. 2013); 3) the lack of compositional variation with ...
... characteristics as high temperature meteorites (type 4 to 6 OCs) that were thermally metamorphosed in their interiors, these exposed interiors being a likely consequence of impacts by small asteroids (D<10km) in the early solar system (Ciesla et al. 2013); 3) the lack of compositional variation with ...
Rotation, activity, and stellar obliquities in a large uniform sample of
... in solar-like stars in the open cluster M67, which is similar to the Sun in both age and metallicity, while Önehag et al. (2011) performed a differential spectroscopic analysis of a solar analog in the same cluster and found it to be nearly indistinguishable from the Sun. Together, these imply a fun ...
... in solar-like stars in the open cluster M67, which is similar to the Sun in both age and metallicity, while Önehag et al. (2011) performed a differential spectroscopic analysis of a solar analog in the same cluster and found it to be nearly indistinguishable from the Sun. Together, these imply a fun ...
Particle-Gas Dynamics and Primary Accretion
... nebula mass M (98% hydrogen and helium) is a small fraction (0.02–0.2) of the stellar mass M*, and cannot yet be measured directly. Current estimates of the surface gas mass density σg(R) (g cm–2), at distance R from the star, are based on assumptions about emission from solid particles, and will un ...
... nebula mass M (98% hydrogen and helium) is a small fraction (0.02–0.2) of the stellar mass M*, and cannot yet be measured directly. Current estimates of the surface gas mass density σg(R) (g cm–2), at distance R from the star, are based on assumptions about emission from solid particles, and will un ...
Abundances and possible diffusion of elements in M 67 stars⋆
... deviation is 46 K. There may be a tendency for the different stellar groups to behave somewhat differently, the MS stars being located higher in Fig. 3 than the SG and TO stars. Such systematic differences may reflect systematic errors in the relative temperatures and the effects of these on the abundan ...
... deviation is 46 K. There may be a tendency for the different stellar groups to behave somewhat differently, the MS stars being located higher in Fig. 3 than the SG and TO stars. Such systematic differences may reflect systematic errors in the relative temperatures and the effects of these on the abundan ...
Richard Congdon. pdf
... Only a few of the elements in the universe were created at its beginning during the Big Bang, namely: hydrogen, deuterium, helium-3 and lithium (1H, 2H, 3He, 7Li). No further stable elements were created at this time because the rapid expansion and cooling, as the Universe expanded into of the void. ...
... Only a few of the elements in the universe were created at its beginning during the Big Bang, namely: hydrogen, deuterium, helium-3 and lithium (1H, 2H, 3He, 7Li). No further stable elements were created at this time because the rapid expansion and cooling, as the Universe expanded into of the void. ...
lhaaso-km2a
... • Began to operate in October 2014 and has been running steadily for more than two years ...
... • Began to operate in October 2014 and has been running steadily for more than two years ...
ppt - chris.engelbrecht.nithep.ac.za
... 1E 0102.2-7219 (Figure 1) is an oxygen-rich supernova remnant in the Small Magellanic Cloud. X-ray observations reveal the blast wave andyield a shock radius of 22 arcseconds at the 60 kpc distance of the SMC. The spectrum of the blast wave yields a temperature of kTx 0.8 keV and an ionization tim ...
... 1E 0102.2-7219 (Figure 1) is an oxygen-rich supernova remnant in the Small Magellanic Cloud. X-ray observations reveal the blast wave andyield a shock radius of 22 arcseconds at the 60 kpc distance of the SMC. The spectrum of the blast wave yields a temperature of kTx 0.8 keV and an ionization tim ...
Parent stars of extrasolar planets III: ρ1 Cancri Revisited
... of the differences in the equivalent widths of those lines common to both spectra are 2–7 mÅ(with most being 2–3 mÅ). In addition, we compared the average equivalent widths of several lines from the new spectra to those from an R = 180,000 spectrum of ρ1 Cnc (with much smaller spectral coverage) u ...
... of the differences in the equivalent widths of those lines common to both spectra are 2–7 mÅ(with most being 2–3 mÅ). In addition, we compared the average equivalent widths of several lines from the new spectra to those from an R = 180,000 spectrum of ρ1 Cnc (with much smaller spectral coverage) u ...
Global Properties of Solar Flares
... The idea that a solar disturbance could affect a terrestrial instrument such as a compass seemed highly improbable at the time, but it turned out to be indeed a correct association, so this first observed flare served to suggest immediately the capability for a such a solar event to have widely felt ...
... The idea that a solar disturbance could affect a terrestrial instrument such as a compass seemed highly improbable at the time, but it turned out to be indeed a correct association, so this first observed flare served to suggest immediately the capability for a such a solar event to have widely felt ...
Pluto Fast Flyby: An Overview of the Mission and
... time frame, its 6,4-day rotation period, its small size, and the spacecraft’s encounter speed, high-resolution imaging will only be possible for part of the South polar region and a fraction of the North polar region. Therefore, a minimum of two spacecraft will be nccdcd, onc for each side of Pluto. ...
... time frame, its 6,4-day rotation period, its small size, and the spacecraft’s encounter speed, high-resolution imaging will only be possible for part of the South polar region and a fraction of the North polar region. Therefore, a minimum of two spacecraft will be nccdcd, onc for each side of Pluto. ...
STELLAR SPECTRA A. Basic Line Formation
... – Schwarzschild, Eddington, Milne, Thomas and many others throughout the twentieth century: development of more general line-formation theory, especially radiation transport through resonance scattering; – Avrett, Auer, Mihalas, Hummer, Rybicki and many others, from 1965: application of computers to ...
... – Schwarzschild, Eddington, Milne, Thomas and many others throughout the twentieth century: development of more general line-formation theory, especially radiation transport through resonance scattering; – Avrett, Auer, Mihalas, Hummer, Rybicki and many others, from 1965: application of computers to ...
The ISO–SWS Spectrum of Planetary Nebula NGC 7027
... NGC 7027 is a well known planetary nebula. It is very young, dense and has an extremely rich and highly ionized spectrum due to its hot central star. The nebula has some features that makes it very interesting. The rich spectrum has been used several times to give insight about the evolution and ori ...
... NGC 7027 is a well known planetary nebula. It is very young, dense and has an extremely rich and highly ionized spectrum due to its hot central star. The nebula has some features that makes it very interesting. The rich spectrum has been used several times to give insight about the evolution and ori ...
Advanced Composition Explorer
Advanced Composition Explorer (ACE) is a NASA Explorers program Solar and space exploration mission to study matter comprising energetic particles from the solar wind, the interplanetary medium, and other sources. Real-time data from ACE is used by the NOAA Space Weather Prediction Center to improve forecasts and warnings of solar storms. The ACE robotic spacecraft was launched August 25, 1997 and entered a Lissajous orbit close to the L1 Lagrangian point (which lies between the Sun and the Earth at a distance of some 1.5 million km from the latter) on December 12, 1997. The spacecraft is currently operating at that orbit. Because ACE is in a non-Keplerian orbit, and has regular station-keeping maneuvers, the orbital parameters at right are only approximate. The spacecraft is still in generally good condition in 2015, and is projected to have enough fuel to maintain its orbit until 2024. NASA Goddard Space Flight Center managed the development and integration of the ACE spacecraft.