Hertzsprung–Russell diagram - Wikipedia, the free encyclopedia
... The original diagram displayed the spectral type of stars on the horizontal axis and the absolute visual magnitude on the vertical axis. The spectral type is not a numerical quantity, but the sequence of spectral types is a monotonic series ordered by stellar surface temperature. Modern observationa ...
... The original diagram displayed the spectral type of stars on the horizontal axis and the absolute visual magnitude on the vertical axis. The spectral type is not a numerical quantity, but the sequence of spectral types is a monotonic series ordered by stellar surface temperature. Modern observationa ...
HOW TO MAKE A SINGLETON sdB STAR VIA ACCELERATED STELLAR... Drew Clausen and Richard A. Wade
... narrow mass distribution of singleton sdBs with precise mass determinations. The problem is that the universe is not yet old enough for this to have occurred in the single star context. Given the usual composition, Y ∼ 0.25–0.28, it takes between 25 and 80 Gyr for these single stars to evolve into s ...
... narrow mass distribution of singleton sdBs with precise mass determinations. The problem is that the universe is not yet old enough for this to have occurred in the single star context. Given the usual composition, Y ∼ 0.25–0.28, it takes between 25 and 80 Gyr for these single stars to evolve into s ...
Ligand to Ligand Charge Transfer in
... ligands are involved in the electron-transfer process. If the band of interest overlaps other bands, interference effects can be observed that require careful interpretation.16,17 Very few emission spectra have been assigned to a LLCT. (Pyridine)(3,4-toluenedithiolato)platinum(II) in an ethanol glas ...
... ligands are involved in the electron-transfer process. If the band of interest overlaps other bands, interference effects can be observed that require careful interpretation.16,17 Very few emission spectra have been assigned to a LLCT. (Pyridine)(3,4-toluenedithiolato)platinum(II) in an ethanol glas ...
Imaging visible light using anisotropic metamaterial slab lens Jie Yao, Kun-Tong Tsai,
... The traditional perception of positive index of refraction has been recently shattered by the introduction of a set of artificial materials with the ability to refract light in anomalous ways. The routes to such materials include the design of simultaneous existence of negative permittivity (ε) and ...
... The traditional perception of positive index of refraction has been recently shattered by the introduction of a set of artificial materials with the ability to refract light in anomalous ways. The routes to such materials include the design of simultaneous existence of negative permittivity (ε) and ...
Lecture 1
... electrons. Hence I means minus 0 electrons – just the neutral atom. Hydrogen has only 1 electron so the highest it can go is HII – which is just a bare proton. ...
... electrons. Hence I means minus 0 electrons – just the neutral atom. Hydrogen has only 1 electron so the highest it can go is HII – which is just a bare proton. ...
MIXED CHEMISTRY
... carbon (HAC) under UV irradiation have been sampled using time of flight (TOF) mass spectrometry. A notable feature is the appearance of … fullerenes such as C50 , C60 , and C70 . There is also evidence in these mass spectra for the ejection of small dehydrogenated polycyclic aromatic hydrocarbon (P ...
... carbon (HAC) under UV irradiation have been sampled using time of flight (TOF) mass spectrometry. A notable feature is the appearance of … fullerenes such as C50 , C60 , and C70 . There is also evidence in these mass spectra for the ejection of small dehydrogenated polycyclic aromatic hydrocarbon (P ...
AN EXPERT COMPUTER PROGRAM FOR CLASSIFYING STARS
... classes) and those show a rather large dispersion when compared to spectral types by human experts. However, the fuzzy logic system has the advantage of providing a probability value for the final classification, and may have an interesting potential if applied within the context of an expert system ...
... classes) and those show a rather large dispersion when compared to spectral types by human experts. However, the fuzzy logic system has the advantage of providing a probability value for the final classification, and may have an interesting potential if applied within the context of an expert system ...
Telescopic Drawings or Photographs of Celestial
... • If more than one task completed the best mark counts • Each task marked using the same markscheme giving 2 marks out of 20 • The 20 marks are split into marks out of 5 for each of the four sections • Design /5 Observation /5 Analysis/5 Evaluation/5 • Design, analysis and evaluation completed under ...
... • If more than one task completed the best mark counts • Each task marked using the same markscheme giving 2 marks out of 20 • The 20 marks are split into marks out of 5 for each of the four sections • Design /5 Observation /5 Analysis/5 Evaluation/5 • Design, analysis and evaluation completed under ...
A self-consistent empirical model atmosphere, abundance and
... Context. Chemically peculiar (CP) stars are unique natural laboratories for the investigation of the microscopic diffusion processes of chemical elements. The element segregation under the influence of gravity and radiation pressure leads to the appearance of strong abundance gradients in the atmosph ...
... Context. Chemically peculiar (CP) stars are unique natural laboratories for the investigation of the microscopic diffusion processes of chemical elements. The element segregation under the influence of gravity and radiation pressure leads to the appearance of strong abundance gradients in the atmosph ...
Article PDF - IOPscience
... center-, major-, and minor-axis radii and major-axis position angle for an isophote at speciÐed surface brightness ; and the routine ELLIPSE in the IRAF reduction package, which uses Fourier techniques to Ðnd the best-Ðtting ellipse corresponding to a speciÐed radius (Jedrzejewski 1987). The latter ...
... center-, major-, and minor-axis radii and major-axis position angle for an isophote at speciÐed surface brightness ; and the routine ELLIPSE in the IRAF reduction package, which uses Fourier techniques to Ðnd the best-Ðtting ellipse corresponding to a speciÐed radius (Jedrzejewski 1987). The latter ...
Seeing Earth`s Orbit in the Stars: Parallax and Aberration
... scientists sometimes succeed in unexpected ways. Bradley sought to confirm Earth’s orbital motion by detecting annual parallax. Instead, he confirmed it by ...
... scientists sometimes succeed in unexpected ways. Bradley sought to confirm Earth’s orbital motion by detecting annual parallax. Instead, he confirmed it by ...
Wave on a String
... Lasers So what do you need to build a laser? 1. Gain Medium - a material with atoms that have a metastable state and that can achieve population inversion 2. Excitation Source - a way to supply energy to excite the atoms ...
... Lasers So what do you need to build a laser? 1. Gain Medium - a material with atoms that have a metastable state and that can achieve population inversion 2. Excitation Source - a way to supply energy to excite the atoms ...
FTIR absorption study of hydroxyl ions in KHo(WO4)2 - DT
... KHo(WO4)2 crystal was heated to 873 K for one hour in air bubbled through D2O and then the absorption spectrum was measured again at low temperature. Fig. 2 shows the spectra in the 2500–2700 cm-1 wave number range where the isotopic replica of the hydroxyl bands appeared. The similarity of the OH– ...
... KHo(WO4)2 crystal was heated to 873 K for one hour in air bubbled through D2O and then the absorption spectrum was measured again at low temperature. Fig. 2 shows the spectra in the 2500–2700 cm-1 wave number range where the isotopic replica of the hydroxyl bands appeared. The similarity of the OH– ...
Evidence for strong evolution in galaxy environmental quenching
... way to the cluster catalogues. We used EAZY (Brammer et al. 2008) to obtain photometric redshifts and the restframe U − V and V − J colours needed to estimate passive and star-forming fractions (Wuyts et al. 2007). We use the Whitaker et al. (2011) U V J criterion, as in vdB+13. We used FAST (Kriek ...
... way to the cluster catalogues. We used EAZY (Brammer et al. 2008) to obtain photometric redshifts and the restframe U − V and V − J colours needed to estimate passive and star-forming fractions (Wuyts et al. 2007). We use the Whitaker et al. (2011) U V J criterion, as in vdB+13. We used FAST (Kriek ...
Sodium Energy Levels Sodium Spectrum
... The sodium spectrum is dominated by the bright doublet known as the Sodium D-lines at 588.9950 and 589.5924 nanometers. From the energy level diagram it can be seen that these lines are emitted in a transition from the 3p to the 3s levels. The line at 589.0 has twice the intensity of the line at 589 ...
... The sodium spectrum is dominated by the bright doublet known as the Sodium D-lines at 588.9950 and 589.5924 nanometers. From the energy level diagram it can be seen that these lines are emitted in a transition from the 3p to the 3s levels. The line at 589.0 has twice the intensity of the line at 589 ...
The Starry Messenger
... Surely it is a great thing to increase the numerous host of fixed stars previously visible to the unaided vision, adding countless more which have never before been seen, exposing these plainly to the eye in numbers ten times exceeding the old and familiar stars. It is a very beautiful thing, and mo ...
... Surely it is a great thing to increase the numerous host of fixed stars previously visible to the unaided vision, adding countless more which have never before been seen, exposing these plainly to the eye in numbers ten times exceeding the old and familiar stars. It is a very beautiful thing, and mo ...
The driving mechanism of starbursts in galaxy mergers
... the overall contribution of mergers to the SF budget of galaxies remains uncertain and quiescent star formation in isolated systems could dominate (Jogee et al. 2009; Robaina et al. 2009; Förster Schreiber et al. 2009; Daddi et al. 2010b). In general, merger-induced SF is assumed to be centrally-co ...
... the overall contribution of mergers to the SF budget of galaxies remains uncertain and quiescent star formation in isolated systems could dominate (Jogee et al. 2009; Robaina et al. 2009; Förster Schreiber et al. 2009; Daddi et al. 2010b). In general, merger-induced SF is assumed to be centrally-co ...
don_lamb - New Views of the Universe
... of greatest remaining mystery of GRBs: The Nature of short GRBs Follow-up observations at X-ray, optical, and radio wavelengths have led to compelling evidence that short GRBs come from merging compact binaries (as David Eichler, Mario Livio, Tsvi Piran, and David Schramm conjectured in 1989) It ...
... of greatest remaining mystery of GRBs: The Nature of short GRBs Follow-up observations at X-ray, optical, and radio wavelengths have led to compelling evidence that short GRBs come from merging compact binaries (as David Eichler, Mario Livio, Tsvi Piran, and David Schramm conjectured in 1989) It ...
Astronomical spectroscopy
Astronomical spectroscopy is the study of astronomy using the techniques of spectroscopy to measure the spectrum of electromagnetic radiation, including visible light, which radiates from stars and other hot celestial objects. Spectroscopy can be used to derive many properties of distant stars and galaxies, such as their chemical composition, temperature, density, mass, distance, luminosity, and relative motion using Doppler shift measurements.