Altair -- the ``hottest`` magnetically active star in X-rays
... in the case of rotational modulation and for the emergence/decay of weakly active regions, in contrast flaring should be accompanied by a spectral hardening. Rotational modulation can be studied with our X-ray data that covers in total three to four stellar rotations. However, the uncertainties in t ...
... in the case of rotational modulation and for the emergence/decay of weakly active regions, in contrast flaring should be accompanied by a spectral hardening. Rotational modulation can be studied with our X-ray data that covers in total three to four stellar rotations. However, the uncertainties in t ...
The Rotation Period and Lightcurve Amplitude of Kuiper Belt Dwarf
... Table 2 and Figures 2 and 3 present our final photometry, as optimized by the process above. The figures present photometry after correction for changes in the Sun-object-Earth phase angle, the geocentric and heliocentric distances, and the light travel time; the table presents uncorrected values. W ...
... Table 2 and Figures 2 and 3 present our final photometry, as optimized by the process above. The figures present photometry after correction for changes in the Sun-object-Earth phase angle, the geocentric and heliocentric distances, and the light travel time; the table presents uncorrected values. W ...
The physics and modes of star cluster formation: observations
... phase of early stellar evolution. As many as 50 per cent of all members of a young cluster may have lost their discs and any other accretion signatures at an age of 2–3 Myr. Observations made from space with X-ray observatories, such as the Chandra X-ray Observatory, have shown that young stars emit ...
... phase of early stellar evolution. As many as 50 per cent of all members of a young cluster may have lost their discs and any other accretion signatures at an age of 2–3 Myr. Observations made from space with X-ray observatories, such as the Chandra X-ray Observatory, have shown that young stars emit ...
Pair instability supernovae: Evolution, explosion, nucleosynthesis
... supernovae are exploding in the visible Universe each second, and at present there are a few of them discovered every day. The average peak luminosity of a supernova competes with that of entire galaxies. Supernovae are the main contributor of heavy elements, energy and momentum to the interstellar ...
... supernovae are exploding in the visible Universe each second, and at present there are a few of them discovered every day. The average peak luminosity of a supernova competes with that of entire galaxies. Supernovae are the main contributor of heavy elements, energy and momentum to the interstellar ...
Stargazing For Beginners: A Binocular Tour of the Southern Night Sky
... This course introduces you to the bright stars and major constellations visible from the Southern Hemisphere, along with dozens of deep-sky sights of interest within each constellation, such as galaxies, binary stars, nebulae, and star clusters. It assumes you are equipped with nothing more than a s ...
... This course introduces you to the bright stars and major constellations visible from the Southern Hemisphere, along with dozens of deep-sky sights of interest within each constellation, such as galaxies, binary stars, nebulae, and star clusters. It assumes you are equipped with nothing more than a s ...
celestial navigation heaven`s guide for mere
... All stars follow a basic series of steps in its lifetime, namely from gas cloud to main sequence followed by red giant, then planetary nebula or supernova and lastly remnant. How long a star lasts at each stage and whether or not a planetary nebula forms or a supernova occurs as well as the type of ...
... All stars follow a basic series of steps in its lifetime, namely from gas cloud to main sequence followed by red giant, then planetary nebula or supernova and lastly remnant. How long a star lasts at each stage and whether or not a planetary nebula forms or a supernova occurs as well as the type of ...
Differential rotation in Sun-like stars from surface variability and
... particles are initially locked to the magnetic field lines out to a radius where the field strength becomes less than the kinetic gas pressure (Weber and Davis 1967, Mestel 1968). At this point (the Alfvén radius) the stellar wind material is released, taking with it AM from the stellar surface and ...
... particles are initially locked to the magnetic field lines out to a radius where the field strength becomes less than the kinetic gas pressure (Weber and Davis 1967, Mestel 1968). At this point (the Alfvén radius) the stellar wind material is released, taking with it AM from the stellar surface and ...
Outline Thesis – so far
... alignment at the telescope ensures that the design specifications can be met during operation. The second part of the thesis concerns the search for planets around a sample of nearby giant stars with the Doppler technique carried out at Lick Observatory‟s CAT telescope. I analyse new data from the p ...
... alignment at the telescope ensures that the design specifications can be met during operation. The second part of the thesis concerns the search for planets around a sample of nearby giant stars with the Doppler technique carried out at Lick Observatory‟s CAT telescope. I analyse new data from the p ...
A Walk through the Southern Sky: A Guide to Stars and
... may have assumed that the brighter star is a bigger star. A very bright star would have a magnitude of 1 or less and a very faint star a magnitude of 6. The smaller the number, the brighter the star. A very ...
... may have assumed that the brighter star is a bigger star. A very bright star would have a magnitude of 1 or less and a very faint star a magnitude of 6. The smaller the number, the brighter the star. A very ...
NGC 6231: a young open cluster under X-rays
... Crowded FOV: 610 sources (mostly PMS) star formation history in NGC 6231: not a punctual event ...
... Crowded FOV: 610 sources (mostly PMS) star formation history in NGC 6231: not a punctual event ...
A new algorithm for fitting orbits of multiple
... provide information. In some cases, the signal from a planet which is not detected above the threshold in either the RV or two-axis astrometric periodogram, will register above the threshold on the three-axis periodogram. We first looked for evidence of ‘hot planets’, using a set of trial frequencie ...
... provide information. In some cases, the signal from a planet which is not detected above the threshold in either the RV or two-axis astrometric periodogram, will register above the threshold on the three-axis periodogram. We first looked for evidence of ‘hot planets’, using a set of trial frequencie ...
Constraining the star formation histories of spiral bulges
... possibility is an initial mass function (IMF) biased towards highmass stars in the early stages of galaxy formation. In this scenario the first few generations of stars generate large quantities of metals (Gibson & Matteucci 1997; Vazdekis et al. 1997). Alternatively, a period of star formation (SF) ...
... possibility is an initial mass function (IMF) biased towards highmass stars in the early stages of galaxy formation. In this scenario the first few generations of stars generate large quantities of metals (Gibson & Matteucci 1997; Vazdekis et al. 1997). Alternatively, a period of star formation (SF) ...
Final Stages of Stellar Evolution - supernovae and the synthesis of
... Final stages of stellar evolution are black dwarfs, neutron stars and black holes, depending on the mass of the star. Heavy elements produced in the s-process in red giant stars and in the r-process in supernova explosions. ...
... Final stages of stellar evolution are black dwarfs, neutron stars and black holes, depending on the mass of the star. Heavy elements produced in the s-process in red giant stars and in the r-process in supernova explosions. ...
A Method of Correcting Near-Infrared Spectra for Telluric Absorption
... spectrum observed nearby in the sky and close in time. Since T(l) varies with air mass and on timescales of the order of several to tens of minutes (depending on the atmospheric conditions), it is clearly best to observe a telluric standard at an air mass as close as possible to that of the target o ...
... spectrum observed nearby in the sky and close in time. Since T(l) varies with air mass and on timescales of the order of several to tens of minutes (depending on the atmospheric conditions), it is clearly best to observe a telluric standard at an air mass as close as possible to that of the target o ...
Here
... This work would not have been possible without the help and support of many people. I would like to take this opportunity to offer my thanks. First and foremost I would like to thank Chris for supervising me through the past three year. I have learnt much from him in this time, from the details of s ...
... This work would not have been possible without the help and support of many people. I would like to take this opportunity to offer my thanks. First and foremost I would like to thank Chris for supervising me through the past three year. I have learnt much from him in this time, from the details of s ...
Astronomy Astrophysics Gaia-ESO Survey: The analysis of high-resolution The
... 2006) photometry (point sources with quality flags “AAA”). A box is defined in a color-magnitude diagram with limits 12 < J < 14 and 0.23 < (J − K) < 0.45 + 0.5 × E(B − V). The Schlegel et al. (1998) maps are used to determine the extinction E(B − V). The targets selected before April 2012 had a bri ...
... 2006) photometry (point sources with quality flags “AAA”). A box is defined in a color-magnitude diagram with limits 12 < J < 14 and 0.23 < (J − K) < 0.45 + 0.5 × E(B − V). The Schlegel et al. (1998) maps are used to determine the extinction E(B − V). The targets selected before April 2012 had a bri ...
SPIRAL STRUCTURE IN THE OUTER GALACTIC
... and crowded stellar fields make membership assignments of faint stars difficult. Yet they contain massive (i.e., hot) stars that can be used to derive their parameters. The classical photometric method to address memberships in young clusters (e.g., Baume et al. 1999) simultaneously checks the consi ...
... and crowded stellar fields make membership assignments of faint stars difficult. Yet they contain massive (i.e., hot) stars that can be used to derive their parameters. The classical photometric method to address memberships in young clusters (e.g., Baume et al. 1999) simultaneously checks the consi ...
Astronomy Astrophysics Excitation of solar-like oscillations across the HR diagram &
... Aims. We extend semi-analytical computations of excitation rates for solar oscillation modes to those of other solar-like oscillating stars to compare them with recent observations Methods. Numerical 3D simulations of surface convective zones of several solar-type oscillating stars are used to chara ...
... Aims. We extend semi-analytical computations of excitation rates for solar oscillation modes to those of other solar-like oscillating stars to compare them with recent observations Methods. Numerical 3D simulations of surface convective zones of several solar-type oscillating stars are used to chara ...
Comprehensive Wide-Band Magnitudes and Albedos for the Planets
... used for brightness references, the optical and sensor hardware employed, the observing procedures and the methods of calibration. The Sloan standard stars of Smith et al. (2002) range from about magnitude r’ = 9 to r’ = 14 and, thus, are generally too faint to serve as references for planetary phot ...
... used for brightness references, the optical and sensor hardware employed, the observing procedures and the methods of calibration. The Sloan standard stars of Smith et al. (2002) range from about magnitude r’ = 9 to r’ = 14 and, thus, are generally too faint to serve as references for planetary phot ...
Mean-Motion Resonances as a Source for Infalling Comets toward
... this model has been termed the falling evaporating body (FEB) scenario. This scenario has been extensively studied in the past years. Dynamical simulations reproduce the observed events in many of their characteristic details (Beust et al. 1990; Beust et al. 1995, and Refs. therein). Moreover, some ...
... this model has been termed the falling evaporating body (FEB) scenario. This scenario has been extensively studied in the past years. Dynamical simulations reproduce the observed events in many of their characteristic details (Beust et al. 1990; Beust et al. 1995, and Refs. therein). Moreover, some ...