Stars with Great Attraction - Max-Planck
... flare lasts, the star releases as much energy as our Sun in 1,000 years. In some objects, the flares are followed by further, weaker bursts after hours or years. The strong magnetic field also plays a role in the case of such a soft gamma-ray repeater. It apparently has an effect on the crust of the ...
... flare lasts, the star releases as much energy as our Sun in 1,000 years. In some objects, the flares are followed by further, weaker bursts after hours or years. The strong magnetic field also plays a role in the case of such a soft gamma-ray repeater. It apparently has an effect on the crust of the ...
Stars
... III. Life cycle of Sun C. Becoming a Red Giant 1. After about 10 billion years, hydrogen is used up 2. Core of star is made of He 3. Layer of gas surrounding core does fusion, causing gases to expand and ...
... III. Life cycle of Sun C. Becoming a Red Giant 1. After about 10 billion years, hydrogen is used up 2. Core of star is made of He 3. Layer of gas surrounding core does fusion, causing gases to expand and ...
Can Superflares Occur on Our Sun?
... Spot group area (area of solar hemisphere) Fig. 2. Flare energy vs. sunspot area for superflares on solar-type stars (filled squares: Maehara et al. 2012) and solar flares (filled circles: Sammis et al. 2000; T. T. Ishii et al. 2012, private communication). The solar flare and sunspot region data are tak ...
... Spot group area (area of solar hemisphere) Fig. 2. Flare energy vs. sunspot area for superflares on solar-type stars (filled squares: Maehara et al. 2012) and solar flares (filled circles: Sammis et al. 2000; T. T. Ishii et al. 2012, private communication). The solar flare and sunspot region data are tak ...
The Sun as an X-Ray Star. III. Flares
... measure distribution versus temperature and its evolution during some selected solar Ñares, representative of the wide range of possible events ; as we did in Paper II we then use these EM(T ) proÐles to synthesize relevant stellar-like spectra, which are then analyzed with standard analysis tools o ...
... measure distribution versus temperature and its evolution during some selected solar Ñares, representative of the wide range of possible events ; as we did in Paper II we then use these EM(T ) proÐles to synthesize relevant stellar-like spectra, which are then analyzed with standard analysis tools o ...
GALEX UV Light-curves of M-Dwarf Flare Stars: THE FLARING UV
... • The magnetic field-lines of a star stretch up into their outer atmosphere - the corona - in loop-like structures • When adjacent magnetic field lines “re-connect” (probably due to disturbances within the stellar interior) they release energy in the form of electrons that gyrate down the field line ...
... • The magnetic field-lines of a star stretch up into their outer atmosphere - the corona - in loop-like structures • When adjacent magnetic field lines “re-connect” (probably due to disturbances within the stellar interior) they release energy in the form of electrons that gyrate down the field line ...
Document
... The wind is depicted spatially in the color plots, with the hue indicating velocity with respect to an observer on the left, and the brightness of the ink indicating emissivity (scaling as density squared). Note the color scale above the third panel. Under each image is the resulting line profile wi ...
... The wind is depicted spatially in the color plots, with the hue indicating velocity with respect to an observer on the left, and the brightness of the ink indicating emissivity (scaling as density squared). Note the color scale above the third panel. Under each image is the resulting line profile wi ...
Science Project
... • Earth's magnetic field stops its atmosphere from being stripped away by the solar wind . Venus and Mars do not have magnetic fields , and as a result, the solar wind causes their atmospheres to gradually bleed away into space . Coronal mass ejections and similar events blow magnetic field and hug ...
... • Earth's magnetic field stops its atmosphere from being stripped away by the solar wind . Venus and Mars do not have magnetic fields , and as a result, the solar wind causes their atmospheres to gradually bleed away into space . Coronal mass ejections and similar events blow magnetic field and hug ...
Session 1: Structure and dynamics of the solar chromosphere
... particularly well observed in the above-mentioned Hα and Ca II lines, but also in a variety of other lines including the UV and EUV spectral range. This will include the structure and dynamics of the chromosphere (cell interior, network, spicules etc.) as well as other features seen at the chromosph ...
... particularly well observed in the above-mentioned Hα and Ca II lines, but also in a variety of other lines including the UV and EUV spectral range. This will include the structure and dynamics of the chromosphere (cell interior, network, spicules etc.) as well as other features seen at the chromosph ...
Upper ionosphere of Mars is not axially symmetrical
... Global Surveyor (MGS) (Vennerstrom et al., 2003) can lead to a more effective screening of the ionosphere in the hemisphere in which the motional electric field is pointed outward the planet (the E + hemisphere). On the other hand, the forces due to the normal and tangential magnetic field tensions ...
... Global Surveyor (MGS) (Vennerstrom et al., 2003) can lead to a more effective screening of the ionosphere in the hemisphere in which the motional electric field is pointed outward the planet (the E + hemisphere). On the other hand, the forces due to the normal and tangential magnetic field tensions ...
Document
... • Surface Gravity – log g (although g is not a dimensionless number). Log g in stars range from 8 for a white dwarf to 0.1 for a supergiant. The sun has log g = 4.44 ...
... • Surface Gravity – log g (although g is not a dimensionless number). Log g in stars range from 8 for a white dwarf to 0.1 for a supergiant. The sun has log g = 4.44 ...
Cosmic Rays near Proxima Centauri b
... of SCR spectrum is unknown to model the effect of SCR one may use spectra of well known solar events (Atri 2017) or average spectrum of solar proton events (Tabataba-Vakili et al. 2016). Another approach is to base on general physical principles (Struminsky & Sadovski 2017) assuming solar-stellar an ...
... of SCR spectrum is unknown to model the effect of SCR one may use spectra of well known solar events (Atri 2017) or average spectrum of solar proton events (Tabataba-Vakili et al. 2016). Another approach is to base on general physical principles (Struminsky & Sadovski 2017) assuming solar-stellar an ...
Magnetic dynamos through driven turbulence
... - large-scale shear is given by Keplerian motion, - angular momentum L r1/ 2, i.e. it should be removed in some way when r 0 - ordinary viscosity is too small - turbulent viscosity requires turbulence and even then it will be small - large-scale poloidal magnetic field can remove angular momentum ...
... - large-scale shear is given by Keplerian motion, - angular momentum L r1/ 2, i.e. it should be removed in some way when r 0 - ordinary viscosity is too small - turbulent viscosity requires turbulence and even then it will be small - large-scale poloidal magnetic field can remove angular momentum ...
Radio and X-ray signatures of merging neutron stars
... & Olbert 1986; Wright & Southwood 1987), in much the same way as Io interacting with Jupiter or various artificial satellites in the Earth's magnetosphere. In this case, the pair production front acts as a surface of finite resistivity, allowing the neutron star to `cross field lines'.1 We assume th ...
... & Olbert 1986; Wright & Southwood 1987), in much the same way as Io interacting with Jupiter or various artificial satellites in the Earth's magnetosphere. In this case, the pair production front acts as a surface of finite resistivity, allowing the neutron star to `cross field lines'.1 We assume th ...
Curriculum Vitae
... 19 Yrs. Undergraduate level 21 Yrs. Taught the following courses: Thermodynamics and Statistical Physics, Optics and Classical Mechanics, Nuclear Physics, Electricity and Electronics, Quantum Mechanics and Spectroscopy, Classical Electrodynamics, Advanced Quantum Mechanics, Microwave Electronics, Ad ...
... 19 Yrs. Undergraduate level 21 Yrs. Taught the following courses: Thermodynamics and Statistical Physics, Optics and Classical Mechanics, Nuclear Physics, Electricity and Electronics, Quantum Mechanics and Spectroscopy, Classical Electrodynamics, Advanced Quantum Mechanics, Microwave Electronics, Ad ...
Composition of the Sun - Indiana University Astronomy
... how sensitively your derived iron abundance depends on temperature and gravity. Derive the solar abundance using several different models to determine how changing the model atmosphere parameters affects the derivation of the solar composition. For example if you use a temperature that is 100K hotte ...
... how sensitively your derived iron abundance depends on temperature and gravity. Derive the solar abundance using several different models to determine how changing the model atmosphere parameters affects the derivation of the solar composition. For example if you use a temperature that is 100K hotte ...
N Brickhouse
... Ne varies only slightly. • Variable Te means rt changes. • Assuming NH is from pre-shock gas, we can get path length
and thus the filling factor.
...
... Ne varies only slightly. • Variable Te means rt changes. • Assuming NH is from pre-shock gas, we can get path length
Here - HESPERIA
... University of Wuerzburg, D-97074 Wuerzburg, Germany The appearances of solar energetic particle events in interplanetary space around the Earth’s orbit, i.e., intensity-time profiles, anisotropies, energy spectra and elemental abundance ratios are determined by a combination of the underlying accele ...
... University of Wuerzburg, D-97074 Wuerzburg, Germany The appearances of solar energetic particle events in interplanetary space around the Earth’s orbit, i.e., intensity-time profiles, anisotropies, energy spectra and elemental abundance ratios are determined by a combination of the underlying accele ...
Solar Orbiter
... The mission design concept meets all the scientific requirements for solar and heliospheric observations close to the Sun (0.21 AU) and at high inclination with respect to the solar equatorial plane (38°). The spacecraft design concept is feasible with the assumption that all the required techno ...
... The mission design concept meets all the scientific requirements for solar and heliospheric observations close to the Sun (0.21 AU) and at high inclination with respect to the solar equatorial plane (38°). The spacecraft design concept is feasible with the assumption that all the required techno ...
Considerations on the use of atmospheric pressure plasma to generate complex molecular environments with relevance for molecular astrophysics
... present in the interstellar medium is represented mainly by atoms and molecules; a small fraction is represents by carbon and silicon based grains. Biogenic elements (i.e. O, C and N) abundance is around 0.1%, while H and He represents more than 99% of atomic matter [1]. Young stellar objects can be ...
... present in the interstellar medium is represented mainly by atoms and molecules; a small fraction is represents by carbon and silicon based grains. Biogenic elements (i.e. O, C and N) abundance is around 0.1%, while H and He represents more than 99% of atomic matter [1]. Young stellar objects can be ...
Kein Folientitel
... Assume a cool neutralizing ion background (immobile), cold Maxwellian electrons and a hot dilute loss-cone component superposed. The dielectric response function is rather complicated (not suggested for an exercise). The region in parameter space of absolute instability is illustrated below (left). ...
... Assume a cool neutralizing ion background (immobile), cold Maxwellian electrons and a hot dilute loss-cone component superposed. The dielectric response function is rather complicated (not suggested for an exercise). The region in parameter space of absolute instability is illustrated below (left). ...
Angular momentum evolution
... Observational constraints • Several thousands of rotational periods now available for solar-type and low-mass stars from ~1 Myr to a ~10 Gyr (0.2-1.2 Msun) • Kepler still expected to yield many more rotational periods for field stars • Several tens of vsini measurements available for VLM stars and ...
... Observational constraints • Several thousands of rotational periods now available for solar-type and low-mass stars from ~1 Myr to a ~10 Gyr (0.2-1.2 Msun) • Kepler still expected to yield many more rotational periods for field stars • Several tens of vsini measurements available for VLM stars and ...
oct8
... Normally, two protons will repel each other with the electrostatic force, but if they are smashed together with enough force they can stay together via the strong nuclear force. ...
... Normally, two protons will repel each other with the electrostatic force, but if they are smashed together with enough force they can stay together via the strong nuclear force. ...
A novel mechanism for electron-cyclotron maser
... Another important instability driven by a fast electron beam is the Langmuir wave (LW) instability, which usually has a much faster growth rate than that of the AW instability. However, this does not imply that the LW instability is more important than the AW instability. The propagation of the LW c ...
... Another important instability driven by a fast electron beam is the Langmuir wave (LW) instability, which usually has a much faster growth rate than that of the AW instability. However, this does not imply that the LW instability is more important than the AW instability. The propagation of the LW c ...
Stellar Magnetic Activity
... Magnetic heating (non-radiative) causes the temperature to rise to a plateau near 7000K (chromosphere); density falls by orders of magnitude Plateau results from a balance between magnetic heating and radiative cooling from collisionally excited Ha, Ca II K, Mg II k – the principal diagnostic lines ...
... Magnetic heating (non-radiative) causes the temperature to rise to a plateau near 7000K (chromosphere); density falls by orders of magnitude Plateau results from a balance between magnetic heating and radiative cooling from collisionally excited Ha, Ca II K, Mg II k – the principal diagnostic lines ...
Corona
A corona (Latin, 'crown') is an aura of plasma that surrounds the sun and other celestial bodies. The Sun's corona extends millions of kilometres into space and is most easily seen during a total solar eclipse, but it is also observable with a coronagraph. The word ""corona"" is a Latin word meaning ""crown"", from the Ancient Greek κορώνη (korōnē, “garland, wreath”).The high temperature of the Sun's corona gives it unusual spectral features, which led some in the 19th century to suggest that it contained a previously unknown element, ""coronium"". Instead, these spectral features have since been explained by highly ionized iron (Fe-XIV). Bengt Edlén, following the work of Grotrian (1939), first identified the coronal lines in 1940 (observed since 1869) as transitions from low-lying metastable levels of the ground configuration of highly ionised metals (the green Fe-XIV line at 5303 Å, but also the red line Fe-X at 6374 Å). These high stages of ionisation indicate a plasma temperature in excess of 1,000,000 kelvin, much hotter than the surface of the sun.Light from the corona comes from three primary sources, which are called by different names although all of them share the same volume of space. The K-corona (K for kontinuierlich, ""continuous"" in German) is created by sunlight scattering off free electrons; Doppler broadening of the reflected photospheric absorption lines completely obscures them, giving the spectral appearance of a continuum with no absorption lines. The F-corona (F for Fraunhofer) is created by sunlight bouncing off dust particles, and is observable because its light contains the Fraunhofer absorption lines that are seen in raw sunlight; the F-corona extends to very high elongation angles from the Sun, where it is called the zodiacal light. The E-corona (E for emission) is due to spectral emission lines produced by ions that are present in the coronal plasma; it may be observed in broad or forbidden or hot spectral emission lines and is the main source of information about the corona's composition.