Absorption Line
An absorption line will appear in a spectrum if an absorbing material is placed between a source and the observer. This material could be the outer layers of a star, a cloud of interstellar gas or a cloud of dust.
absorption line: A dark line in a spectrum; produced by the absence of photons absorbed by atoms or molecules.
absorption spectrum (dark-line spectrum): A spectrum that contains absorption lines.
Absorption line: A dark line or band at a particular wavelength on a spectrum, formed when a substance between a radiating source and an observer absorbs electromagnetic radiation of that wavelength.
absorption line Dark line in an otherwise continuous bright spectrum, where light within one narrow frequency range has been removed.
acceleration The rate of change of velocity of a moving object.
absorption line
A narrow dark line within a spectrum. It is caused by specific gases absorbing a portion of radiation, and its width represents the relative abundance of the gases.
Absorption Line - A dark line superimposed on a continuous spectrum when a gas absorbs light from a continuous source that is hotter than the absorbing gas ...
Absorption line. A break of depression in a continuous spectrum caused by the absorption of photons within narrow wavelengths by some types of atom, ion, or molecule.
absorption lines
dark lines in a spectrum caused by the absorption of light by atoms or molecules in a star or planet's atmosphere
accretion disk ...
ABSORPTION LINES
When sunlight is split by a prism, at first glance it appears to produce a continuous spectrum.
ABSORPTION LINE - Narrow range of wavelengths in a spectrum that are darker (have lower intensity) than neighboring wavelengths.
Absorption lines Dark lines interrupting a continuous color spectrum, caused by a cool gas between the light source and the observer. Cool gas absorbs light in the same frequencies as it emits when hot, e.g. double yellow line of sodium.
Absorption Lines
Dark lines in a spectrum, produced when light or other electromagnetic radiation coming from a distant source passes through a gas cloud or similar object closer to the observer.
Absorption lines of KrI
No Kr line is seen in the solar spectrum.
Absorption lines of KrII
Following Bidelman's (1960) discovery of KrII in 3 Cen A, this element was observed in some other hot Bp stars. W(4355) = 0.025 according to Hardorp (1966).
Absorption lines
A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range, compared with the nearby frequencies.
Contents ...
Absorption Lines: Dark lines superimposed over a bright continuous spectrum background, created when a cooler gas absorbs photons from a hotter source.
ABSORPTION LINES
Absorption Lines are dark lines superimposed over a bright continuous absorption spectrum. Each dark line is formed as a cooler gas absorbs photons emitted by a particular element from a hotter source.
Absorption lines from hydrogen in quasar spectra tells us that there is a lot of material between us and the quasars.
Gravitational Lensing ...
The absorption lines in stellar spectra can be used to determine the chemical composition of the star.
The absorption line of neutral calcium at 4227 Angstroms is thus strong in cool M-type dwarf stars, in which the pressure is high and the temperature is low.
The absorption lines of a solar or other stellar spectrum.
frequency - (n.) ...
Dark absorption lines in the sun's spectrum and that of other stars are called Fraunhofer lines after Joseph von Fraunhofer (1787-1826) who observed them in 1817.
Broad absorption lines are direct evidence of outflow from AGNs, at very respectable velocities.
A spectrum of absorption lines or bands, produced when light from a hot source, itself producing a continuous spectrum, passes through a cooler gas.
Relatively few absorption lines. Lines of ionized helium and other lines of highly ionized atoms. Hydrogen lines appear only weakly. Peak of light in UV part of spectrum.
Naos
B ...
absorption line (NASA SP-7, 1965) A minute range of wavelength (or frequency) in the electromagnetic spectrum within which radiant energy is absorbed by the medium through which it is passing.
Stellar spectra
Absorption lines from photosphere
Hydrogen Balmer series changes in strength :
weak at low temp : all in ground state (n=1)
weak at high temp : all ionized
strongest at about 10,000K (A0 stars) ...
A certain absorption line that is found at 5000 Angstroms in the lab is found at 5050 Angstroms when analyzing the spectrum of a particular galaxy.
H-alpha. This absorption line of neutral hydrogen falls in the red part of the visible spectrum and is convenient for solar observations. The H-alpha line is universally used for observations of solar flares.
telluric lines Absorption lines in a solar spectrum produced by constituents of the atmosphere of the earth itself rather than by gases in the outer solar atmosphere such as those responsible for the Fraunhofer lines.
Generally speaking, the same absorption lines are present, but with altered intensities, which differ from one spot to another.
Asymmetric absorption line profiles are the result of the superposition of multiple absorption lines, each corresponding to the same atomic transition (for example the "K" line of calcium), ...
A second candidate was identified by methane absorption lines in Gliese 229B, a faint object orbiting the M1 star Gliese 229 in the constellation Lepus, 18.6 light years away.
Most prominent would be the star itself, and whatever emission and absorption lines come from the star's surface. But what about the gas?
This detection helps explain the physical shape of previously poorly-understood related ice absorption lines.
Orton et al.
Note the characteristic absorption line features including strong lines for Hα, Hβ, Hγ and Hδ - the Balmer Series. The overall shape of the spectrum approximates a black body curve with a peak wavelength.
Within this spectra, astronomers can study emission and absorption lines which are the fingerprints of atoms and molecules. An emission line occurs when an electron drops down to a lower orbit around the nucleus of an atom and loses energy.
These locations are called absorption lines and are caused by a particular element in the star's atmosphere.
A dark-line spectrum (also called a absorption spectrum) consists of dark absorption lines superimposed on a bright continuous spectrum.
Gamma Velorum also has the nickname the Spectral Gem of the Southern Skies because it emits bright lines instead of dark absorption lines, which results in an exotic looking spectrum.
B stars have spectra that are characterized by absorption lines of neutral helium which reach their maximum intensity at B2, and strong Balmer lines of hydrogen and lines of singly ionized oxygen and other gases.
Fraunhofer line - An absorption line in the spectrum of the sun or a star.
Fraunhofer spectrum - The array of absorption lines in the spectrum of the sun or of a star.
(Although 500 times more abundant than methane, hydrogen has much weaker absorption lines because it is a molecule of two identical atoms that interacts only very weakly with electromagnetic waves.) Subsequent studies led to a growing list of new ...
B
Balmer lines (J. Balmer)
Emission or absorption line in the spectrum of hydrogen that arise from transitions between the second (or first excited) state and higher energy states of the hydrogen atom.
He assigned letters to the black absorption lines in the Solar Spectrum. These resonance lines arise from energy absorption by elements in the outer atmospheres of stars that are cooler than the stellar gases below. Back to Top
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Johannes Franz Hartmann (1865-1936) was a German astrophysicist who, in 1904, discovered clouds of interstellar calcium gas (he detected the absorption lines of ionized calcium atoms using spectrography while studying binary stars).
Arrows denote methane absorption lines.The discovery team followed up their initial identification of 2003 UB313 with spectroscopic observations made at the 8 m Gemini North Telescope in Hawaii on January 25, 2005.
This field absorbs certain wavelengths, creating specific absorption lines in the spectrum. These are the cyclotron resonance absorption lines that allow the direct measurement of the magnetic field strength.
This group comprises the so-called hydrogen stars with spectra dominated by the absorption lines of hydrogen. A typical star of this group is Sirius, the Dog Star.
Class F ...
Spectrometers are instruments that spread light out into wavelengths called "spectra," which look something like rainbow-colored bars. Using the spectra, scientists can look for and study the "emission lines" and "absorption lines" that are sort ...
It was taken from an American Observatory and shows a continuous spectrum displayed over 50 strips. Within each strip the vertical black bars are absorption lines which give information about the chemical composition of the star.
A rainbow is a natural spectrum of visible light from the Sun. Spectra are often punctuated with emission or absorption lines, which can be examined to reveal the composition and motion of the radiating source.
If some EM wave with continuum spectrum passes through some low pressure atoms (e.g. the outer atmosphere of a star), those atoms will absorb the light it likes and creates an absorption line.
(Image: © European Southern Observatory) Astronomers then used the VLT's 8.2-m Kueyen telescope to obtain a spectrum of the objects. This superimposed the light of the two stars, but the combined result shows the deep absorption lines expected from ...
(The higher the gravity, the more the compression of the gas, and the closer the atoms are to each other, which affects the way in which they produce their absorption lines.) The gravity in turn depends on mass and radius.
This can be seen by taking a frequency spectrum of an object and matching the spectroscopic pattern of emission lines or absorption lines corresponding to atoms of the chemical elements interacting with the light.
Spectra are often punctuated with emission or absorption lines, which can be examined to reveal the composition and motion of the radiating source.
 See also: Absorption, Spectrum, Light, Emission, Element
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