Statistical survey of widely spread out solar electron events
... Context. In February 2011, the two STEREO spacecrafts reached a separation of 180 degrees in longitude, offering a complete view of the Sun for the first time ever. When the full Sun surface is visible, source active regions of solar energetic particle (SEP) events can be identified unambiguously. ST ...
... Context. In February 2011, the two STEREO spacecrafts reached a separation of 180 degrees in longitude, offering a complete view of the Sun for the first time ever. When the full Sun surface is visible, source active regions of solar energetic particle (SEP) events can be identified unambiguously. ST ...
Lillis_et_al-2010-Journal_of_G
... Figure 1. (a) A typical magnetic field‐altitude profile for a region of strong crustal field. (b) The pitch angle evolution which this profile dictates for electrons starting at 400 km altitude at 6 different pitch angles: 15, 24, 27, 30, 33, 40 degrees (i.e., the pitch angle at the lower right end ...
... Figure 1. (a) A typical magnetic field‐altitude profile for a region of strong crustal field. (b) The pitch angle evolution which this profile dictates for electrons starting at 400 km altitude at 6 different pitch angles: 15, 24, 27, 30, 33, 40 degrees (i.e., the pitch angle at the lower right end ...
Spot sizes on Sun-like stars
... due to incomplete phase coverage, there are considerable variations in the filling factors measured for the same star by the same group, but at different times. In order to be able to compare them to the spot coverage fractions listed in columns 6 and 8 in Table 2 we converted them to a ‘minimum’ an ...
... due to incomplete phase coverage, there are considerable variations in the filling factors measured for the same star by the same group, but at different times. In order to be able to compare them to the spot coverage fractions listed in columns 6 and 8 in Table 2 we converted them to a ‘minimum’ an ...
X-ray astronomy - University of Warwick
... 13.6-100 eV is extreme-ultraviolet (EUV) >~100 keV is gamma rays Low/high energy corresponds to soft/hard X-rays ...
... 13.6-100 eV is extreme-ultraviolet (EUV) >~100 keV is gamma rays Low/high energy corresponds to soft/hard X-rays ...
Origin and Evolution of Neutron Star Magnetic Fields - if
... Fields and Neutron Stars, this presentation has the purpose of giving a general overview about what is currently known about neutron star magnetic fields, their origin and evolution. Inevitably, it will contain much of the same material presented by the author in similar reviews in previous years (e. ...
... Fields and Neutron Stars, this presentation has the purpose of giving a general overview about what is currently known about neutron star magnetic fields, their origin and evolution. Inevitably, it will contain much of the same material presented by the author in similar reviews in previous years (e. ...
STELLAR SPECTRA A. Basic Line Formation
... These three exercises concern the appearance and nature of spectral lines in stellar spectra. Stellar spectrometry laid the foundation of astrophysics in the hands of: – Wollaston (1802): first observation of spectral lines in sunlight; – Fraunhofer (1814–1823): rediscovery of spectral lines in sunl ...
... These three exercises concern the appearance and nature of spectral lines in stellar spectra. Stellar spectrometry laid the foundation of astrophysics in the hands of: – Wollaston (1802): first observation of spectral lines in sunlight; – Fraunhofer (1814–1823): rediscovery of spectral lines in sunl ...
- Spiral - Imperial College London
... swer to this question. While the regime of the TSI variability over the 11-year cycle is well-established – it varies in phase with solar activity (see e.g. Fröhlich 2006; Ball et al. 2012; Solanki et al. 2013, and references therein), the regime of the solar variability in the visible part of the ...
... swer to this question. While the regime of the TSI variability over the 11-year cycle is well-established – it varies in phase with solar activity (see e.g. Fröhlich 2006; Ball et al. 2012; Solanki et al. 2013, and references therein), the regime of the solar variability in the visible part of the ...
Magnetars: properties, origin and evolution
... also emit intermediate and giant flares, the latter involving the release of up to about 1046 erg in less than half a second. Magnetars also show pulsed X-ray emission with typical luminosity of ∼ 1035 erg s−1 in persistent sources, and ranging from ∼ 1032 to 1036 erg s−1 in transient ones. The puls ...
... also emit intermediate and giant flares, the latter involving the release of up to about 1046 erg in less than half a second. Magnetars also show pulsed X-ray emission with typical luminosity of ∼ 1035 erg s−1 in persistent sources, and ranging from ∼ 1032 to 1036 erg s−1 in transient ones. The puls ...
Cosmological Implications of Trace
... hypothesis will be shown to lead to simple conventional physics explanations for effects commonly attributed to unconventional forms of dark energy or dark matter, often called ΛCDM . For example, the strong jetting observed in AGNs can be created if matter ionizes near the event horizon of a positi ...
... hypothesis will be shown to lead to simple conventional physics explanations for effects commonly attributed to unconventional forms of dark energy or dark matter, often called ΛCDM . For example, the strong jetting observed in AGNs can be created if matter ionizes near the event horizon of a positi ...
Seismic Observations of the Solar Interior
... a few minutes to several hours and with horizontal wavelengths of between less than a few thousand kilometers to global scales. Each mode can be regarded as a resonant standing wave whose traveling constituents propagate in a well defined spherical shell in the solar interior. The lower boundary of ...
... a few minutes to several hours and with horizontal wavelengths of between less than a few thousand kilometers to global scales. Each mode can be regarded as a resonant standing wave whose traveling constituents propagate in a well defined spherical shell in the solar interior. The lower boundary of ...
Dynamics of an electric current-carrying string loop near a
... energy of the string which is proportional to B2s is negligibly small in comparison with those of the external magnetic field which is estimated as 108 G for stellar mass black holes and 104 G for supermassive black hole. On the other hand, in the following we will not neglect the interaction of t ...
... energy of the string which is proportional to B2s is negligibly small in comparison with those of the external magnetic field which is estimated as 108 G for stellar mass black holes and 104 G for supermassive black hole. On the other hand, in the following we will not neglect the interaction of t ...
Light perturbation from stellar non radial oscillations: an application
... • Taking into account sphericity of the photosphere reveals a possible significant increase of the relative intensity perturbation at the solar limb for some modes of oscillation: - both for p and g-modes - and only for l+m even modes • The effect on the full-disk perturbation is expected to be smal ...
... • Taking into account sphericity of the photosphere reveals a possible significant increase of the relative intensity perturbation at the solar limb for some modes of oscillation: - both for p and g-modes - and only for l+m even modes • The effect on the full-disk perturbation is expected to be smal ...
Persistence of the Gleissberg 88-year solar cycle over
... at about A.D. 1911 and that it is negatively correlated with the Gleissberg cycle of mean sunspot numbers. In another work by Sofia et al. [1985] the historical record of the Sun’s diameter obtained from timings of eclipses was subject to harmonic analysis with one period equal to 90 years. The ampl ...
... at about A.D. 1911 and that it is negatively correlated with the Gleissberg cycle of mean sunspot numbers. In another work by Sofia et al. [1985] the historical record of the Sun’s diameter obtained from timings of eclipses was subject to harmonic analysis with one period equal to 90 years. The ampl ...
スライド 1
... Looking down onto the ecliptic plane from above, a CIR near Earth's orbit is sketched. The Sun is off the bottom of the figure. The CIR is shaded in tan, and the Earth's track through the CIR is depicted as the green dashed line. In the reference frame of this sketch, the Earth moves downward with t ...
... Looking down onto the ecliptic plane from above, a CIR near Earth's orbit is sketched. The Sun is off the bottom of the figure. The CIR is shaded in tan, and the Earth's track through the CIR is depicted as the green dashed line. In the reference frame of this sketch, the Earth moves downward with t ...
Quiescent and flaring X-ray emission from the nearby M/T dwarf
... September 2008 for approximately 20 ks (Obs.ID 0551022901); data analysis was carried out with the standard XMM software, the Science Analysis System (SAS) version 9.0 (de la Calle & Loiseau 2008). XMM-Newton carries three X-ray CCD cameras with moderate spectral resolution, as well as two X-ray gra ...
... September 2008 for approximately 20 ks (Obs.ID 0551022901); data analysis was carried out with the standard XMM software, the Science Analysis System (SAS) version 9.0 (de la Calle & Loiseau 2008). XMM-Newton carries three X-ray CCD cameras with moderate spectral resolution, as well as two X-ray gra ...
Lower Atmospheric Physics - National Open University of Nigeria
... temperature increases with altitude. The increase in temperature with height continues until a local maximum is reached at a height of about 50 kilometers. This local maximum defines the stratopause. The stratopause is the upper boundary region of the stratosphere. The stratosphere is very stable. F ...
... temperature increases with altitude. The increase in temperature with height continues until a local maximum is reached at a height of about 50 kilometers. This local maximum defines the stratopause. The stratopause is the upper boundary region of the stratosphere. The stratosphere is very stable. F ...
The magnetic field of epsilon Eri
... maintained by the dierential rotation of the star. The Sun has dierent layers or zones: the core, the radiative zone and the convective zone. The radiative zone and the core rotate as if they were a solid body, while the convective zone has dierential rotation. Between the layers, there is a thin ...
... maintained by the dierential rotation of the star. The Sun has dierent layers or zones: the core, the radiative zone and the convective zone. The radiative zone and the core rotate as if they were a solid body, while the convective zone has dierential rotation. Between the layers, there is a thin ...
Comparative Planetology
... Earth’s magnetospheric dynamics are driven by variations in the solar wind, which generate substorms and geomagnetic storms reflected in perturbations to the magnetic field morphology as well as in the aurora. Jupiter’s magnetosphere appears to be rotationally driven, due to both the rapid rotation ...
... Earth’s magnetospheric dynamics are driven by variations in the solar wind, which generate substorms and geomagnetic storms reflected in perturbations to the magnetic field morphology as well as in the aurora. Jupiter’s magnetosphere appears to be rotationally driven, due to both the rapid rotation ...
Associated Spectral and Temporal State Transition of the
... Stellar mass black hole X-ray binaries exhibit X-ray spectral states which also have distinct and characteristic temporal properties. These states are believed to correspond to different accretion disc geometries. We present analysis of two XMM-Newton observations of the Ultra-Luminous X-ray source ...
... Stellar mass black hole X-ray binaries exhibit X-ray spectral states which also have distinct and characteristic temporal properties. These states are believed to correspond to different accretion disc geometries. We present analysis of two XMM-Newton observations of the Ultra-Luminous X-ray source ...
Main-Sequence Stars and the Sun
... held more tightly, and the energy required for the excitation step is higher, compared with the corresponding steps in the neutral atom. Most elements will readily ionize at the high end of the temperature range of G stars; therefore, absorption by neutral atoms is absent in types G through O. In io ...
... held more tightly, and the energy required for the excitation step is higher, compared with the corresponding steps in the neutral atom. Most elements will readily ionize at the high end of the temperature range of G stars; therefore, absorption by neutral atoms is absent in types G through O. In io ...
Nanoscale magnetometry with NV centers in diamond
... off as the separation cubed. It also means that bringing the sensor widely used in spin-based magnetometers such as atomic vapor closer to the sample places it in a stronger field and therefore cells, is to monitor changes in spin precession.13 This type of results in faster detection times. Fulfillin ...
... off as the separation cubed. It also means that bringing the sensor widely used in spin-based magnetometers such as atomic vapor closer to the sample places it in a stronger field and therefore cells, is to monitor changes in spin precession.13 This type of results in faster detection times. Fulfillin ...
Letter to the Editor - Max-Planck
... Key words. X-rays: binaries – stars: individual: Cygnus X-1, XTE J1118+480 – radiation mechanisms: non-thermal ...
... Key words. X-rays: binaries – stars: individual: Cygnus X-1, XTE J1118+480 – radiation mechanisms: non-thermal ...
on limiting the thickness of the solar tachocline
... reproduced from Rogers (2011). Although we ran models with two magnetic field strengths, Bo = 40G and Bo = 4000G, all of the results presented will be only for the strong field case because the weak field case is virtually identical to the nonmagnetic case. In all models, the boundary conditions are ...
... reproduced from Rogers (2011). Although we ran models with two magnetic field strengths, Bo = 40G and Bo = 4000G, all of the results presented will be only for the strong field case because the weak field case is virtually identical to the nonmagnetic case. In all models, the boundary conditions are ...
Astronomy and Astrophysics 336, 972, 1998
... stages should be made whenever possible. Therefore, we chose a single main-sequence star that is somewhat cooler than the Sun as a target for repeated Doppler imaging, but we emphasize that the Doppler-imaging technique per se requires a much more rapidly rotating star than the Sun and our target, w ...
... stages should be made whenever possible. Therefore, we chose a single main-sequence star that is somewhat cooler than the Sun as a target for repeated Doppler imaging, but we emphasize that the Doppler-imaging technique per se requires a much more rapidly rotating star than the Sun and our target, w ...
Magnetized massive stars as magnetar progenitors
... stellar surface and the consideration of a rebound shock breaking through the stellar interior and envelope, we find a remnant compact object (i.e. neutron star) left behind at the centre with a radius of ∼106 cm and a mass range of ∼1−3 M . Moreover, we find that surface magnetic fields of such a ...
... stellar surface and the consideration of a rebound shock breaking through the stellar interior and envelope, we find a remnant compact object (i.e. neutron star) left behind at the centre with a radius of ∼106 cm and a mass range of ∼1−3 M . Moreover, we find that surface magnetic fields of such a ...
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.