Counting Sunspots - Lunar and Planetary Institute
... are caused by the Sun's magnetic field welling up to the photosphere, the Sun's visible http://www.windows.ucar.edu/coloring_book/SS_Beg_new2.pdf "surface". The powerful magnetic fields around sunspots produce active regions on the Sun, which often lead to solar flares and Coronal Mass Ejections (CM ...
... are caused by the Sun's magnetic field welling up to the photosphere, the Sun's visible http://www.windows.ucar.edu/coloring_book/SS_Beg_new2.pdf "surface". The powerful magnetic fields around sunspots produce active regions on the Sun, which often lead to solar flares and Coronal Mass Ejections (CM ...
Observations of the Magnetic Fields Inside and Outside the
... currents are mostly alternating, the senses of the assoicated magnetic fields will also reverse with time. The above-ground lines can be seriously affected by the passage of solar magnetic storms speeding away from the Sun and encountering the Earth. In 1994, Canada's Anik-E1 and Anik-E2 communicati ...
... currents are mostly alternating, the senses of the assoicated magnetic fields will also reverse with time. The above-ground lines can be seriously affected by the passage of solar magnetic storms speeding away from the Sun and encountering the Earth. In 1994, Canada's Anik-E1 and Anik-E2 communicati ...
Gamma-Ray Pulsars - INTEGRAL
... of charges in the regions above the magnetic poles (‘polar cap’) and between the zero charge density surfaces (nGJ = 0) and the equatorial magnetosphere close to rc (‘outer gaps’). In these gaps the electrostatic potential of the rotating dipole is not balanced by charges and is available to acceler ...
... of charges in the regions above the magnetic poles (‘polar cap’) and between the zero charge density surfaces (nGJ = 0) and the equatorial magnetosphere close to rc (‘outer gaps’). In these gaps the electrostatic potential of the rotating dipole is not balanced by charges and is available to acceler ...
Gamma-Ray Bursts as Sources of Strong Magnetic Fields
... new t0 . Overall such a model requires a the magnetic field that is extremely large initially, leading to the prompt emission and then it decreases, just at the right time (and before all the rotational energy is exhausted) to a lower level in which the weaker magnetar powers (using the remaining ro ...
... new t0 . Overall such a model requires a the magnetic field that is extremely large initially, leading to the prompt emission and then it decreases, just at the right time (and before all the rotational energy is exhausted) to a lower level in which the weaker magnetar powers (using the remaining ro ...
Sample pages 1 PDF
... illustrated, albeit less dramatically, by the comparison of the soft state spectra of black holes and neutron stars, as discussed later in this chapter. The upper end of the relevant temperature range is achieved in the limit of the optically thin emission. It is not unreasonable to link it to the v ...
... illustrated, albeit less dramatically, by the comparison of the soft state spectra of black holes and neutron stars, as discussed later in this chapter. The upper end of the relevant temperature range is achieved in the limit of the optically thin emission. It is not unreasonable to link it to the v ...
The Trouble with Cosmological Magnetic Fields
... or even larger coherence scales Filaments: There are indications of magnetic fields in filaments with strengths up to B ∼ 10−8 – 10−7 Gauss and coherence scales over 1Mpc (Kronberg 2010). ...
... or even larger coherence scales Filaments: There are indications of magnetic fields in filaments with strengths up to B ∼ 10−8 – 10−7 Gauss and coherence scales over 1Mpc (Kronberg 2010). ...
A Review of the 0.1 Reconnection Rate Problem
... is near 0.1 when normalized to a properly defined reconnecting magnetic field and Alfvén speed. That this is the case has been known for many years, but developing a theoretical understanding of why has been extremely challenging. If we already know the typical rate, why is it important to solve th ...
... is near 0.1 when normalized to a properly defined reconnecting magnetic field and Alfvén speed. That this is the case has been known for many years, but developing a theoretical understanding of why has been extremely challenging. If we already know the typical rate, why is it important to solve th ...
A Legacy Study of Stellar Life Cycles in the Galactic Center
... • Microquasars and some pulsars might have required luminosity and hard spectrum in high state • Fluorescent line seen in Sgr B2, Sgr C, and central parsecs of Galaxy, so would need multiple microquasars, such as GRS 1915+10, but none of them would currently be bright. • Need sources that are bright ...
... • Microquasars and some pulsars might have required luminosity and hard spectrum in high state • Fluorescent line seen in Sgr B2, Sgr C, and central parsecs of Galaxy, so would need multiple microquasars, such as GRS 1915+10, but none of them would currently be bright. • Need sources that are bright ...
Simulating the outer layers of Procyon A: a comparison with the Sun
... back again over a time of 20–30 min. This motion, which is driven by the granulation, takes place in a time approximately half the turnover time of the largest granules. (iii)The peak rms velocity in the vertical direction is much larger in Procyon A. The main reason for the radically different radi ...
... back again over a time of 20–30 min. This motion, which is driven by the granulation, takes place in a time approximately half the turnover time of the largest granules. (iii)The peak rms velocity in the vertical direction is much larger in Procyon A. The main reason for the radically different radi ...
Magnetism in Isolated and Binary White Dwarfs
... Following the discovery by Babcock (1947) of a polar magnetic Ðeld of D1500 G in the Ap star 78 Vir, it became apparent that sizeable magnetic Ðelds were present in stars other than the Sun. If magnetic Ñux was conserved during stellar evolution, white dwarfs should be expected to have magnetic Ðeld ...
... Following the discovery by Babcock (1947) of a polar magnetic Ðeld of D1500 G in the Ap star 78 Vir, it became apparent that sizeable magnetic Ðelds were present in stars other than the Sun. If magnetic Ñux was conserved during stellar evolution, white dwarfs should be expected to have magnetic Ðeld ...
Accreting Neutron Stars: Strong Gravity and Type I Bursts
... Another technique under investigation is asteroseismology. This is a fairly new approach in NSs and is still at its very early stages. However, in principle, analyzing different frequencies found during the bursts of magnetars (NSs with magnetic fields above ∼ 1014 G, Watts, 2011), or the signals en ...
... Another technique under investigation is asteroseismology. This is a fairly new approach in NSs and is still at its very early stages. However, in principle, analyzing different frequencies found during the bursts of magnetars (NSs with magnetic fields above ∼ 1014 G, Watts, 2011), or the signals en ...
Cool Stars in the Galaxy — A ROSAT and ASCA View.
... lution instruments on Skylab (Reeves 1976, Vaiana et al. 1973) showed the solar corona to be composed of complex loop structures associated with underlying photospheric and chromospheric features, in particular magnetic field structures. Also in the 1970’s, the detection of X-ray quiescent and flari ...
... lution instruments on Skylab (Reeves 1976, Vaiana et al. 1973) showed the solar corona to be composed of complex loop structures associated with underlying photospheric and chromospheric features, in particular magnetic field structures. Also in the 1970’s, the detection of X-ray quiescent and flari ...
Simulating the outer layers of Procyon A: a comparison with the Sun
... the height of the solar superadiabatic peak. When the outer part of the SAL is in an optically thin region, the photons can more readily carry away excess internal energy from the temperature fluctuations, than they can in optically thick regions. As it looses its excess internal energy compared to ...
... the height of the solar superadiabatic peak. When the outer part of the SAL is in an optically thin region, the photons can more readily carry away excess internal energy from the temperature fluctuations, than they can in optically thick regions. As it looses its excess internal energy compared to ...
Analysis of Stellar Activity and Orbital Dynamics in Extrasolar
... The area of exoplanet research, which emerged less than two decades ago, was revolutionized with the advent of space-based photometers like CoRoT and Kepler. These observatories provide long-term monitoring of thousands of stars with unprecendented accuracy and high time resolution to detect transit ...
... The area of exoplanet research, which emerged less than two decades ago, was revolutionized with the advent of space-based photometers like CoRoT and Kepler. These observatories provide long-term monitoring of thousands of stars with unprecendented accuracy and high time resolution to detect transit ...
On the Origin of Cosmic Magnetic Fields
... and represents a certain bias on their part. Generally, reviews of galactic magnetic fields discuss the magnetic fields in a great variety of extragalactic systems. This in general is justified since, by examining the global shapes and properties of fields in external galaxies one can form a much be ...
... and represents a certain bias on their part. Generally, reviews of galactic magnetic fields discuss the magnetic fields in a great variety of extragalactic systems. This in general is justified since, by examining the global shapes and properties of fields in external galaxies one can form a much be ...
Origin of solar surface activity and sunspots Sarah Jabbari Nordita, Stockholm, Sweden
... In the last few years, there has been significant progress in the development of a new model for explaining magnetic flux concentrations, by invoking the negative effective magnetic pressure instability (NEMPI) in a highly stratified turbulent plasma. According to this model, the suppression of the ...
... In the last few years, there has been significant progress in the development of a new model for explaining magnetic flux concentrations, by invoking the negative effective magnetic pressure instability (NEMPI) in a highly stratified turbulent plasma. According to this model, the suppression of the ...
Irregular Shock Refraction in Magnetohydrodynamics
... roots of the Rankine-Hugoniot relations, which in this case are all real and entropy increasing. From other upstream regimes, 2 → 3 and 2 → 4 transitions are also intermediate shocks, while 3 → 4 transitions are known as slow shocks. A further type of discontinuity propagates at cI and has no effect ...
... roots of the Rankine-Hugoniot relations, which in this case are all real and entropy increasing. From other upstream regimes, 2 → 3 and 2 → 4 transitions are also intermediate shocks, while 3 → 4 transitions are known as slow shocks. A further type of discontinuity propagates at cI and has no effect ...
Photospheric processes and magnetic flux tubes
... The equations for a hydrostatic flux tube (cont.) Pizzo (1990) used a “body-fitted” nonorthogonal coordinate system to map the physical domain into a unit square computational domain. A multigrid elliptic solver is used at each iteration stage for solving Ampère’s equation. Fiedler & Cally (1991) ...
... The equations for a hydrostatic flux tube (cont.) Pizzo (1990) used a “body-fitted” nonorthogonal coordinate system to map the physical domain into a unit square computational domain. A multigrid elliptic solver is used at each iteration stage for solving Ampère’s equation. Fiedler & Cally (1991) ...
CHAPTER 3 MICROWAVE DIAGNOSTICS
... Recently, an oblique view ECE system has been developed for the JET tokamak where the ECE radiation is detected along lines of sight at a small angle rather than the standard perpendicular view with the aim of probing the low-energy portion of the electron distribution function since departures from ...
... Recently, an oblique view ECE system has been developed for the JET tokamak where the ECE radiation is detected along lines of sight at a small angle rather than the standard perpendicular view with the aim of probing the low-energy portion of the electron distribution function since departures from ...
Solar Math - GLORIA Project
... http://spacemath.gsfc.nasa.gov Add your email address to our mailing list by contacting Dr. Sten Odenwald at [email protected] ...
... http://spacemath.gsfc.nasa.gov Add your email address to our mailing list by contacting Dr. Sten Odenwald at [email protected] ...
9th Conference of Hel.A.S. Athens, 20
... Metric radio bursts and fine structures observed on 20 January, 2005 Combining ground-based and space magnetic measurements for investigating the Earth's magnetosphere Energetic Neutral Atom (ENA) Production from ions trapped in Saturn's Magnetosphere Simulating flaring events via an intelligent Cel ...
... Metric radio bursts and fine structures observed on 20 January, 2005 Combining ground-based and space magnetic measurements for investigating the Earth's magnetosphere Energetic Neutral Atom (ENA) Production from ions trapped in Saturn's Magnetosphere Simulating flaring events via an intelligent Cel ...
Section IV High-Energy Astrophysics and Cosmology
... velocities (“kicks”) of the final merged black holes via anisotropic gravitational radiation up to several thousands km/s [33, 34, 35]. The basic feature of the gravitational wave (GW) recoil effect is the situation when the SMBH spends a significant fraction of time off nucleus at scales beyond tha ...
... velocities (“kicks”) of the final merged black holes via anisotropic gravitational radiation up to several thousands km/s [33, 34, 35]. The basic feature of the gravitational wave (GW) recoil effect is the situation when the SMBH spends a significant fraction of time off nucleus at scales beyond tha ...
IBEX
... Slide 17: An infrared image of interstellar material, imaged by the Spitzer Space Telescope. Slide 17 Image credit: NASA/JPLCaltech/E. Churchwell (University of Wisconsin) ...
... Slide 17: An infrared image of interstellar material, imaged by the Spitzer Space Telescope. Slide 17 Image credit: NASA/JPLCaltech/E. Churchwell (University of Wisconsin) ...
The Earliest Stages of Star and Planet Formation: Core Collapse
... (vrot ∝ r−1 ) between ∼ 102 and 104 AU, as expected from conservation of angular momentum under infall. A rotationally supported disk is expected to show increasing specific angular momentum as function of radius (Keplerian rotation, vrot ∝ r−0.5 ). To characterize the properties of disks being form ...
... (vrot ∝ r−1 ) between ∼ 102 and 104 AU, as expected from conservation of angular momentum under infall. A rotationally supported disk is expected to show increasing specific angular momentum as function of radius (Keplerian rotation, vrot ∝ r−0.5 ). To characterize the properties of disks being form ...
Get
... interpolation between neighboring data of the extinction index κ and the refractive index n. The optical constants of free space at all wavelengths are known as n = 1 and κ = 0. Figure 1(b) also shows the dependence of κ and n within the wavelength range from 300 to 1100 nm. This range is usually us ...
... interpolation between neighboring data of the extinction index κ and the refractive index n. The optical constants of free space at all wavelengths are known as n = 1 and κ = 0. Figure 1(b) also shows the dependence of κ and n within the wavelength range from 300 to 1100 nm. This range is usually us ...
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.