Doppler effects Doppler effects Blue shift is the opposite of redshift, the latter being much more noted due to its importance to modern astronomy. It is also used informally to refer to a hypsochromic shift in photochemistry. ...more on Wikipedia about "Blue shift"
Johann Christian Andreas Doppler ( November 29, 1803 in Salzburg – March 17, 1853 in Venice) was an Austrian mathematician and physicist, most famous for the hypothesis of what is now known as the Doppler effect which causes the frequency of a wave to apparently change as its source moves toward or away from the observer. ...more on Wikipedia about "Christian Doppler"
In atomic physics, Doppler broadening is the broadening of spectral lines due to the Doppler effect in which the thermal movement of atoms or molecules shifts the apparent frequency of each emitter. The many different velocities of the emitting gas result in many small shifts, the cumulative effect of which is to broaden the line. The broadening is dependent only on the wavelength of the line, the mass of the emitting particle and the temperature, and can therefore be a very useful method for measuring the temperature of an emitting gas. ...more on Wikipedia about "Doppler broadening"
The Doppler effect, named after Christian Andreas Doppler, is the apparent change in frequency or wavelength of a wave that is perceived by an observer moving relative to the source of the waves. For waves, such as sound waves, that propagate in a wave medium, the velocity of the observer and the source are reckoned relative to the medium in which the waves are transmitted. The total Doppler effect may therefore result from either motion of the source or motion of the observer. Each of these effects is analyzed separately. For waves which do not require a medium (such as light or gravity in Special Relativity) only the relative difference in velocity between the observer and the source needs to be considered. ...more on Wikipedia about "Doppler effect"
For acoustic effects concerning sound, the form of the Doppler equations depends partly on the state of motion of the sound medium (usually air) relative to the source and detector. ...more on Wikipedia about "Doppler equations"
In spectroscopy, the Doppler profile is a spectral line profile which results from the thermal motion of the emitting atom or molecule. When thermal motion causes a particle to move towards the observer, the emitted radiation will be shifted to a higher frequency. Likewise, when the emitter moves away, the frequency will be lowered. For non-relativistic thermal velocities, the Doppler shift in frequency will be: ...more on Wikipedia about "Doppler profile"
Doppler radar uses the Doppler effect to return additional information from a radar system. The Doppler effect shifts the frequency of the radar beam due to movement of the "target", allowing for the direct and highly accurate measurement of speeds. Doppler radars were originally developed for military radar systems, but have since become a part of almost all radar systems, including weather radar and radar guns for traffic police and sports. ...more on Wikipedia about "Doppler radar"
Laser Doppler velocimetry (LDV, also known as laser Doppler anemometry, or LDA) is a technique for measuring the direction and speed of fluids like air and water. In its simplest form, LDV crosses two beams of collimated, monochromatic light in the flow of the fluid being measured. A microscopic pattern of bright and dark stripes forms in the intersection volume. Small particles in the flow pass through this pattern and reflect light towards a detector, with a characteristic frequency indicating the velocity of the particle passing through the probe volume. ...more on Wikipedia about "Laser Doppler velocimetry"
In special relativity, many key relationships depart from both Newtonian mechanics and classical theory by a special velocity-dependent term that we can call a Lorentz term , due to its earlier appearance in Lorentzian electrodynamics. ...more on Wikipedia about "Lorentz term"
In physics and astronomy, redshift is an observed increase in the wavelength of electromagnetic radiation received by a detector compared to that emitted by the source. For visible light, red is the color with the longest wavelength, so colors experiencing redshift actually shift towards the red part of the electromagnetic spectrum. The phenomenon goes by the same name even if it occurs at non-optical wavelengths (in fact, longer-wavelength radiation actually shifts away from red). The corresponding shift to shorter wavelengths is called blueshift. ...more on Wikipedia about "Redshift"
The relativisitic Doppler effect is the change in frequency (and wavelength) of light, caused by the relative motion of the source and the observer (like in the regular Doppler effect), when taking into account effects of the special theory of relativity. ...more on Wikipedia about "Relativistic Doppler effect"
The Rossiter-McLaughlin effect is an spectroscopic phenomenon seen when either an eclipsing binary's secondary star or an extrasolar planet is seen to transit across the face of the primary or parent star. As a main star rotates on its axis, one quadrant of the photosphere will be seen to be coming towards the viewer, and the other quadrant seen to be moving away. These produce differing redshifts in the star's spectrum, usually observed as a broadening of the spectral lines. When the secondary star or planet transits the primary, it blocks off part of the solar disc, obscuring some of the red- or blue-shifted light from reaching the observer. This causes the observed mean redshift of the primary star as a whole to vary from its previous value. As the transiting object moves across to the other side of the star's disc, so the redshift anomaly will switch from being negative to being positive (or vice versa). ...more on Wikipedia about "Rossiter-McLaughlin effect"
Relative motion between objects does not just affect the frequency of received light-signals (the usual Doppler effect on light) it also affects the apparent dimensions that differently-moving objects will see each other to have when using those light-signals. This has been referred to as the spatial analogue of the Doppler effect. ...more on Wikipedia about "Spatial Doppler effect"
In special relativity, the transverse Doppler effect is the nominal redshift component associated with transverse (i.e. non-longitudinal) motion, and is important both theoretically and experimentally. ...more on Wikipedia about "Transverse Doppler effect"
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