High Resolution Chandra Spectroscopy of Gamma Cassiopeia (B0
... et al. 1999, Apparao 2002). Potentially, this picture can explain in a general way the hard thermal spectrum of the X-rays. However, while the star is now established as part of a binary system (see Harmanec et al. 2000; Miroshnichenko, Bjorkman, & Krugov 2002), the wide separation (P ≈ 204 days, wi ...
... et al. 1999, Apparao 2002). Potentially, this picture can explain in a general way the hard thermal spectrum of the X-rays. However, while the star is now established as part of a binary system (see Harmanec et al. 2000; Miroshnichenko, Bjorkman, & Krugov 2002), the wide separation (P ≈ 204 days, wi ...
Galaxies
... • They often look like a star, due to their great distance (the rest of their galaxy structure can’t be seen). • Many quasars reveal more structure when viewed in radio wavelengths. ...
... • They often look like a star, due to their great distance (the rest of their galaxy structure can’t be seen). • Many quasars reveal more structure when viewed in radio wavelengths. ...
Radial velocity planet detection biases at the stellar rotational period
... orbits with RV semi-amplitudes half the typical amplitude of the stellar activity signal and with randomly distributed orbital phases. After generating the simulated RV time series, we began analysis to attempt to mitigate the stellar RV signal and recover the planets. We fit a line to the measured ...
... orbits with RV semi-amplitudes half the typical amplitude of the stellar activity signal and with randomly distributed orbital phases. After generating the simulated RV time series, we began analysis to attempt to mitigate the stellar RV signal and recover the planets. We fit a line to the measured ...
STRUCTURAL CHARACTERISTICS AND STELLAR
... smaller HSB galaxies rather than coalescence into enormous smooth structures like Malin 1 (Bothun et al. 1987), which would fall well below and to the right of the lower right corner of Figure 4 (Impey & Bothun 1989). Despite being low in surface brightness, the integrated magnitudes of LSB galaxies ...
... smaller HSB galaxies rather than coalescence into enormous smooth structures like Malin 1 (Bothun et al. 1987), which would fall well below and to the right of the lower right corner of Figure 4 (Impey & Bothun 1989). Despite being low in surface brightness, the integrated magnitudes of LSB galaxies ...
HD 24355 observed by the Kepler K2 mission: A rapidly oscillating
... Tautenburg, Germany, which we discuss in section 3. Table 1 gives details of all spectral observations. The phases have been calculated relative to the second pulsational maximum in the K2 data set, such that: φ(E) = 245 7108.8867 + 27.d 9158 × E, ...
... Tautenburg, Germany, which we discuss in section 3. Table 1 gives details of all spectral observations. The phases have been calculated relative to the second pulsational maximum in the K2 data set, such that: φ(E) = 245 7108.8867 + 27.d 9158 × E, ...
Lecture 2. Isolated Neutron Stars – I.
... Then using there average lifetime we can estimate the birth rate and total numbers (with a given age of the Galaxy and assuming constant rate) taking into account SFR~3 solar mass per year. [see also Ch.1 in Shapiro, Teukolsky] ...
... Then using there average lifetime we can estimate the birth rate and total numbers (with a given age of the Galaxy and assuming constant rate) taking into account SFR~3 solar mass per year. [see also Ch.1 in Shapiro, Teukolsky] ...
Kepler-63b: A Giant Planet in a Polar Orbit around a Young Sun
... relationship is caused by a physical process or is merely a coincidence, it has an important consequence for the interpretation of spot-crossing anomalies, as pointed out by Winn et al. (2010b) in the context of the HAT-P-11 system. The near-commensurability causes a “stroboscopic” effect in the pat ...
... relationship is caused by a physical process or is merely a coincidence, it has an important consequence for the interpretation of spot-crossing anomalies, as pointed out by Winn et al. (2010b) in the context of the HAT-P-11 system. The near-commensurability causes a “stroboscopic” effect in the pat ...
Homework extension
... in nuclear reactors are Uranium-235 and Plutonium-239. For fission to occur the U-239 or P-239 must first absorb a neutron. The nucleus then undergoes fission and splits into two smaller nuclei and two or three neutrons, energy is also released. The neutrons released may go on to cause other nuclei ...
... in nuclear reactors are Uranium-235 and Plutonium-239. For fission to occur the U-239 or P-239 must first absorb a neutron. The nucleus then undergoes fission and splits into two smaller nuclei and two or three neutrons, energy is also released. The neutrons released may go on to cause other nuclei ...
azu_etd_13224_sip1_m
... structure, and host star abundances play in the different stages of planet formation? In this thesis, beginning with a brief literature review in Chapter 2, I trace oxygen and carbon species through these stages to inform how, when, and where planets form. In Chapter 3 I describe a study of the mole ...
... structure, and host star abundances play in the different stages of planet formation? In this thesis, beginning with a brief literature review in Chapter 2, I trace oxygen and carbon species through these stages to inform how, when, and where planets form. In Chapter 3 I describe a study of the mole ...
EVIDENCE FOR IMF VARIATIONS WITH GALACTIC ENVIRONMENT
... for Leo IV. All images were dithered to mitigate detector artifacts and enable resampling of the point spread function (PSF). Our image processing includes the latest pixel-based correction for charge-transfer inefficiency (Anderson & Bedin 2010). We co-added the images for each filter in a given ti ...
... for Leo IV. All images were dithered to mitigate detector artifacts and enable resampling of the point spread function (PSF). Our image processing includes the latest pixel-based correction for charge-transfer inefficiency (Anderson & Bedin 2010). We co-added the images for each filter in a given ti ...
Phase-resolved high-resolution spectrophotometry of the eclipsing
... cosmics which were identified by Laplace-filtering of the raw images. Sky-subtraction was performed afterwards in the usual manner by fitting polynomials to CCD-columns above and below the region exposed to the target star. Next, the spatial coordinate of individual pixels along the slit had to be t ...
... cosmics which were identified by Laplace-filtering of the raw images. Sky-subtraction was performed afterwards in the usual manner by fitting polynomials to CCD-columns above and below the region exposed to the target star. Next, the spatial coordinate of individual pixels along the slit had to be t ...
Sardinia_SA - Mullard Space Science Laboratory
... but the states tend to be called “high”, “intermediate” and “low” • In low states the accretion rate drops, no reservoir in a disk, so the underlying stars can become visible: important for measuring the system parameters ...
... but the states tend to be called “high”, “intermediate” and “low” • In low states the accretion rate drops, no reservoir in a disk, so the underlying stars can become visible: important for measuring the system parameters ...
DOC - IVOA
... parameters of objects) or data (FITS files describing wavelengths and fluxes) for groups of like stars without making explicit searches by star name one at a time or by cross correlation of established catalogs. This is a common request to archive centers holding spectroscopic datasets. NASA’s Inter ...
... parameters of objects) or data (FITS files describing wavelengths and fluxes) for groups of like stars without making explicit searches by star name one at a time or by cross correlation of established catalogs. This is a common request to archive centers holding spectroscopic datasets. NASA’s Inter ...
Gravitational Waves from 3D MHD Core
... of flux-freezing and field winding leads to conditions where the ratio of magnetic field pressure to matter pressure reaches about unity which leads to the onset of a jet-like supernova explosion. The collimated bipolar out-stream of matter is then reflected in the emission of a type IV GW signal. I ...
... of flux-freezing and field winding leads to conditions where the ratio of magnetic field pressure to matter pressure reaches about unity which leads to the onset of a jet-like supernova explosion. The collimated bipolar out-stream of matter is then reflected in the emission of a type IV GW signal. I ...
A Rotational and Variability Study of a Large Sample of... in NGC 2264 M. H. Lamm , C. A. L. Bailer-Jones
... in the young (2–4 Myr) open cluster NGC 2264, based on photometric monitoring using the Wide Field Imager (WFI) on the 2.2 m telescope on La Silla (Chile). In total, about 10600 stars with IC magnitudes between 9.8 mag and 21 mag have been monitored in our 340 × 330 field. Time series data were obta ...
... in the young (2–4 Myr) open cluster NGC 2264, based on photometric monitoring using the Wide Field Imager (WFI) on the 2.2 m telescope on La Silla (Chile). In total, about 10600 stars with IC magnitudes between 9.8 mag and 21 mag have been monitored in our 340 × 330 field. Time series data were obta ...
Stellar evolution
Stellar evolution is the process by which a star changes during its lifetime. Depending on the mass of the star, this lifetime ranges from a few million years for the most massive to trillions of years for the least massive, which is considerably longer than the age of the universe. The table shows the lifetimes of stars as a function of their masses. All stars are born from collapsing clouds of gas and dust, often called nebulae or molecular clouds. Over the course of millions of years, these protostars settle down into a state of equilibrium, becoming what is known as a main-sequence star.Nuclear fusion powers a star for most of its life. Initially the energy is generated by the fusion of hydrogen atoms at the core of the main-sequence star. Later, as the preponderance of atoms at the core becomes helium, stars like the Sun begin to fuse hydrogen along a spherical shell surrounding the core. This process causes the star to gradually grow in size, passing through the subgiant stage until it reaches the red giant phase. Stars with at least half the mass of the Sun can also begin to generate energy through the fusion of helium at their core, whereas more-massive stars can fuse heavier elements along a series of concentric shells. Once a star like the Sun has exhausted its nuclear fuel, its core collapses into a dense white dwarf and the outer layers are expelled as a planetary nebula. Stars with around ten or more times the mass of the Sun can explode in a supernova as their inert iron cores collapse into an extremely dense neutron star or black hole. Although the universe is not old enough for any of the smallest red dwarfs to have reached the end of their lives, stellar models suggest they will slowly become brighter and hotter before running out of hydrogen fuel and becoming low-mass white dwarfs.Stellar evolution is not studied by observing the life of a single star, as most stellar changes occur too slowly to be detected, even over many centuries. Instead, astrophysicists come to understand how stars evolve by observing numerous stars at various points in their lifetime, and by simulating stellar structure using computer models.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.