Galaxy Disks Further
... disk mass distribution can be obtained from hydrostatic considerations, comparing the thickness and velocity dispersion of the stars, as was pioneered for the Galaxy by Kapteyn (1922) and Oort (1932), or the HI gas (van der Kruit 1981). Sanders & McGaugh (2002) have reviewed modified Newtonian dynam ...
... disk mass distribution can be obtained from hydrostatic considerations, comparing the thickness and velocity dispersion of the stars, as was pioneered for the Galaxy by Kapteyn (1922) and Oort (1932), or the HI gas (van der Kruit 1981). Sanders & McGaugh (2002) have reviewed modified Newtonian dynam ...
Globular Cluster Bimodality in Isolated Elliptical Galaxies
... composition and are roughly at the same distance from the earth (differing only in their masses), forming rare astrophysical “laboratories”. A globular cluster (GC) is a roughly spherical group of stars, orbiting a galactic core, tightly bound by gravity with high stellar density towards the center. ...
... composition and are roughly at the same distance from the earth (differing only in their masses), forming rare astrophysical “laboratories”. A globular cluster (GC) is a roughly spherical group of stars, orbiting a galactic core, tightly bound by gravity with high stellar density towards the center. ...
The distributions and ages of refractory objects in the solar nebula
... important to understand the setting in which they formed. Protoplanetary disks, such as those thought to serve as analogs for our own solar nebula, evolve over time as mass is transported inward and accreted onto the central star in its last stages of pre-main sequence evolution. To compensate for t ...
... important to understand the setting in which they formed. Protoplanetary disks, such as those thought to serve as analogs for our own solar nebula, evolve over time as mass is transported inward and accreted onto the central star in its last stages of pre-main sequence evolution. To compensate for t ...
... fields of COROT. In this thesis we present the first step of this project, which is the preparation and study of the sample of Be stars that will be observed by COROT. We have performed photometric analysis of all Be stars located in the seismology fields (Chapt. 2). Special emphasis has been given ...
Astronomy
... originate outside the Earth's atmosphere (such as the cosmic background radiation). It is concerned with the evolution, physics, chemistry, meteorology, and motion of celestial objects, as well as the formation and development of the universe. Astronomy is one of the oldest sciences. Prehistoric cul ...
... originate outside the Earth's atmosphere (such as the cosmic background radiation). It is concerned with the evolution, physics, chemistry, meteorology, and motion of celestial objects, as well as the formation and development of the universe. Astronomy is one of the oldest sciences. Prehistoric cul ...
The CCD Photometric Calibration Cookbook
... CCD (Charge-Coupled Device) photometric calibration is concerned with converting the arbitrary units in which CCD images are recorded into standard, reproducible units. In principle the observed brightness could be calibrated into genuine physical units, such as W m , and indeed this is occasionally ...
... CCD (Charge-Coupled Device) photometric calibration is concerned with converting the arbitrary units in which CCD images are recorded into standard, reproducible units. In principle the observed brightness could be calibrated into genuine physical units, such as W m , and indeed this is occasionally ...
Understanding Variable Stars - Central Florida Astronomical Society
... perspective, an introduction to stars in general, the techniques for discovering and studying variable stars, and a description of the main types of variable stars. It ends with short reflections about the connection between the study of variable stars, and research, education, amateur astronomy, and ...
... perspective, an introduction to stars in general, the techniques for discovering and studying variable stars, and a description of the main types of variable stars. It ends with short reflections about the connection between the study of variable stars, and research, education, amateur astronomy, and ...
Galactic Winds Sylvain Veilleux
... Stellar evolutionary models have reproduced successfully most properties of WolfRayet (WR) stars, but overpredict WR mass-loss rates. In general, combined empirical results and theoretical predictions are used instead of model-derived mass-loss rates (Leitherer et al. 1992). For an instantaneous sta ...
... Stellar evolutionary models have reproduced successfully most properties of WolfRayet (WR) stars, but overpredict WR mass-loss rates. In general, combined empirical results and theoretical predictions are used instead of model-derived mass-loss rates (Leitherer et al. 1992). For an instantaneous sta ...
Title The Correlation between Dispersion Measure and X
... and c is the speed of light. Most free electrons in our Galaxy are found in the hot phase of the ISM, including H ii regions ionized by UV radiation from hot O or B type stars and the shock-heated interior of supernova remnants (SNRs). These sources can contribute significant DM up to a few hundred ...
... and c is the speed of light. Most free electrons in our Galaxy are found in the hot phase of the ISM, including H ii regions ionized by UV radiation from hot O or B type stars and the shock-heated interior of supernova remnants (SNRs). These sources can contribute significant DM up to a few hundred ...
Astrophysics of Dust in Cold Clouds
... Dust plays an increasingly important role in astrophysics. Historically, dust was first recognized for its obscuring effects, and the need to correct observed intensities for attenuation by dust continues today. But with the increasing sensitivity of IR, FIR, and submm telescopes, dust is increasing ...
... Dust plays an increasingly important role in astrophysics. Historically, dust was first recognized for its obscuring effects, and the need to correct observed intensities for attenuation by dust continues today. But with the increasing sensitivity of IR, FIR, and submm telescopes, dust is increasing ...
PhD thesis - Hamburger Sternwarte
... The term activity is not clearly defined. A definition for the term activity or nonradiative activity provided by Linsky (1985) is the following: ”phenomena and physical properties that occur when the energy balance in a stellar atmosphere departs greatly from pure radiative equilibrium”. In this de ...
... The term activity is not clearly defined. A definition for the term activity or nonradiative activity provided by Linsky (1985) is the following: ”phenomena and physical properties that occur when the energy balance in a stellar atmosphere departs greatly from pure radiative equilibrium”. In this de ...
environmental effects on galaxy evolution in nearby clusters
... is studied. The main goals of this thesis are: (a) The study of the dependence of the UV emission of galaxies from their morphological type, mass and the environment they inhabit, through the study of UV luminosity functions and color magnitude relations. (b) The study of UV dust extinction properti ...
... is studied. The main goals of this thesis are: (a) The study of the dependence of the UV emission of galaxies from their morphological type, mass and the environment they inhabit, through the study of UV luminosity functions and color magnitude relations. (b) The study of UV dust extinction properti ...
X-ray and Gamma-ray Studies of the Millisecond Pulsar and
... presented in Crawford et al. (2013). 3. X-RAY ORBITAL VARIABILITY Using the radio timing ephemeris of PSR J1723–2837 (Crawford et al. 2013) we have determined the orbital phases of the barycentered XMM-Newton and Chandra source photons. Each observation cover approximately a single orbit. Largeampli ...
... presented in Crawford et al. (2013). 3. X-RAY ORBITAL VARIABILITY Using the radio timing ephemeris of PSR J1723–2837 (Crawford et al. 2013) we have determined the orbital phases of the barycentered XMM-Newton and Chandra source photons. Each observation cover approximately a single orbit. Largeampli ...
Star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as ""stellar nurseries"" or ""star-forming regions"", collapse to form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.