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Absorption Line

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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 at a particular wavelength. of a spectrum, formed when a cool, tenuous gas between a hot radiating source and the observer absorbs electromagnetic radiation of that wavelength. ACE Advanced Composition Explorer.

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.
acceleration: A change in a velocity; a change in either speed or direction. (See velocity.) ...

absorption line: a more or less narrow range of wavelengths in a spectrum that is darker than neighboring wavelengths. Absorption lines are seen in stars.

absorption line
A dark line in a spectrum that represents the absorption of energy at a particular wavelength of light. Each element on the periodic table absorbs energy at unique wavelengths.

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.
accretion
The process of growth of an object due to the gradual accumulation of material.

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
Acceleration - The rate of change of velocity. An acceleration may involve a change of speed, direction of motion, or both ...

absorption line spectrum
Dark lines superimposed on a continuous spectrum.
acceleration
The rate at which an object's velocity changes due to a change in speed, a change in direction, or both.

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 are a dark feature in the spectrum of a star formed by cooler gases in a star's outer layer.

ABSORPTION LINES
When sunlight is split by a prism, at first glance it appears to produce a continuous spectrum. However, closer scrutiny with a spectroscope shows that the solar spectrum is interrupted by a large number of narrow dark lines, as shown in Figure 4.4.

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 line The visible light spectrum of the cool giant star Arcturus ( Bootis) is shown here. The dark vertical lines in the spectrum are caused by atoms in the star's atmosphere absorbing radiation.

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.

An absorption line is produced when a photon of just the right energy is absorbed by an atom, kicking an electron to a higher energy orbit. The photon had energy = the difference in energy of the energy orbits.

Absorption lines of PI
The equivalent width of PI 9796(2) in the sun is 0.012. According to Underhill (1977) it is present in an A 2Ia star.
Absorption lines of PII
The PII line 4127(16) is presentin B 5Ia stars and ultraviolet lines are also visible in B 7 and B 9V stars (Artru et al. 1989).

Absorption Line
A dark line in a continuous spectrum caused by absorption of light.

Absorption lines against a continuous spectrum are seen as the photons emitted at particular wavelengths are emitted in all directions, so would produce a dark line.
(b) The largest transition would give a photon of the shortest wavelength. This would be from n = 6 to n = 2.
(c) This is at 410 nm ...

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
Narrow spectral features that represent a reduction in intensity over a small wavelength range. They are caused by the loss of photons that raise an atom from a particular energy state to a higher energy state.
absorption spectrum ...

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.

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. The image below shows a segment of the solar spectrum, in which many such lines can be seen.

Broad absorption lines are direct evidence of outflow from AGNs, at very respectable velocities. The primary questions are then (1) what is this absorbing region and (2) is the BAL phenomenon an intrinsic property of a few QSOs or do most QSOs look like this if viewed from certain directions?

You get absorption lines when you look straight through the cloud of gas and dust at a background Star. The light that got absorbed that caused those dark lines when you're looking straight through the cloud of gas and dust is going to get re-emitted.

Emission and absorption lines in radio astronomy usually originate from atoms and small molecules or molecular ions in gaseous form, and molecular transitions at radio wavelengths are usually rotational.

Search for absorption lines from the evaporated atmosphere of extrasolar planets in the visible.
April 7, 2007 COUSTENIS A., MAYOR M., SCHNEIDER J., QUELOZ D. & EGGENBERGER A.
abstract ...

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.

absorption line. In spectroscopy, and in particular the solar Fraunhofer spectrum, a characteristic wavelength of emitted radiation that is partially absorbed by the medium between the source and the observer. (See H alpha.) active.

absorption line The absence or reduction of radiation at one or several adjacent wavelengths in a continuous spectrum. absorption spectrum Continuous spectrum interrupted by absorption lines or a continuous spectrum having a number of discrete wavelengths missing or reduced in intensity.

Passing a continuous beam of radiation through cool gas will produce absorption lines at precisely the same frequencies as are present in the gas's emission spectrum. Kirchhoff's laws describe the relationships among these different types of spectra.

The ratio of the absorption line strengths, together with models of the CO molecule, allow one to deduce the relative number of molecules in the J = 0, 1, 2, and 3 levels (of rotational energy).

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.

p=39938#comment-434673 Ganzy (5) said:

Can someone correct me please if I'm wrong, but if I were to analyze the entire spectrum of light that is being given off by this cargo ship burning up on re-entry, would I expect to see black absorption lines in specific parts of the spectrum that ...

The reason temperatures affect absorption lines is not too difficult to understand in a general way. Absorption lines are produced when an electron of an atom is moved from one orbital shell to another one of higher energy through the absorption of a photon.

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), but occurring in interstellar clouds with different radial velocities.

The precise position (wavelength) at which known emission and absorption lines are detected can be used to measure the redshift of the observed object. For example, if the spectral line of Hβ (486.2 nm) is detected at 487.

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. It appears to have a mass of , and to be 44 AU away from Gliese 229 (Glanz 1995, Oppenheimer et al. 1995).

Most prominent would be the star itself, and whatever emission and absorption lines come from the star's surface. But what about the gas?

Therefore the frequency of this absorption line directly measures the magnetic field strength near Her X-1. The observed photon energy corresponds to the frequency
$$\nu = {E \over h} \approx { 34 \times 10^3 {\rm ~eV} \times 1.60 \times 10^{-12} {\rm erg~eV}^{-1} \over 6.

Every element has a characteristic temperature range over which it produces prominent absorption lines in the observable part of the spectrum (3).

This detection helps explain the physical shape of previously poorly-understood related ice absorption lines.
Orton et al. 1982 A spectrum of the disk of Jupiter was obtained from the Kuiper Airborne Observatory, covering the 100 to 300 cm^-1 spectral range.

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.

I have a question about broadened absorption lines. In "Discovering the Universe" by Comins and Kaufmann, it is mentioned that cool main sequence stars have broader absorption lines than hot main sequence stars. I believe that this effect is due to pressure broadening.

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. This can be used to determine the effective temperature of the star.

A dark-line spectrum (also called a absorption spectrum) consists of dark absorption lines superimposed on a bright continuous spectrum. An absorption spectrum is created when light from an incandescent source passes through a cooler gas that absorbs photons.

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. Gamma Velorum is actually a multiple star system, composed of at least six stars.

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.

The infrared part of the spectrum is where the emission and absorption lines of virtually all molecules as well as numerous atoms and ions (electrically charged atoms) lie. Infrared spectroscopy is the primary way to detect these elements in space.

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
- G - ...

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).

- Apodis (Eta Apodis) is classified as an Am star or metallic-line star, an A-type star that is chemically peculiar and whose spectrum has strong absorption lines of some metals and deficiencies of others.

The infrared spectrum of 2003 UB313, compared to that of Pluto, shows the marked similarities between the two bodies. Arrows denote methane absorption lines.

* As x-rays leave a neutron star, they have to pass through the star's magnetic field. 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.

A hot variable star with peculiar emission and absorption lines in its spectrum.
PENROSE PROCESS
A mechanism for extracting rotational energy from a black hole.

Electromagnetic radiation arranged in order of wavelength. 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.
Substorm current wedge ...

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 of fingerprints of atoms and molecules that may be ...

This is a detailed spectrum of the star Arcturus - a red giant. 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.

The CBR had, however, been detected and its temperature deduced in 1941, seven years before Gamow's prediction. Based on the study of narrow absorption line features in the spectra of stars, ...

In an optical spectroscope, the detector is your eye, which senses the different colors and the presence of dark absorption lines or bright emission lines in the spectrum of the source being viewed. In a spectrograph, some other device is used to sense the light.

Hidden in the rainbow is a series of bright or dark lines (called emission and absorption lines) that are caused by chemical elements in the object the light is coming from. These lines act like a sort of chemical barcode that allows you to identify the element that created it.

Damped Lyman Alpha Absorbers (also: Damped Lyman alpha systems or Damped Lyman alpha absorption systems) are gaseous objects detected in the spectra of quasars, with a column density larger than 1020 atoms/cm2. Their spectra consist of neutral hydrogen Lyman alpha absorption lines, ...

(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 a red dwarf.

(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. Gravity measure with the above radius gives a mass of 1.

Spectra are often punctuated with emission or absorption lines, which can be examined to reveal the composition and motion of the radiating source.
Sunspot A temporary disturbed area in the solar photosphere that appears dark because it is cooler than the surrounding areas.

The resulting spectrum of light allows one to locate the emission and absorption lines, determine the composition of the star, its doppler shift, its spectral type, and its luminosity class.
SPECTRUM: The range of color produced when light is split up by a prism of diffraction grating.

See also: See also: What is the meaning of Absorption lines, Spectrum, Spectra, Astro, Solar?

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