Ejecta

Definitions

  • Webster's Revised Unabridged Dictionary
    • n. pl Ejecta Matter ejected; material thrown out; as, the ejecta of a volcano; the ejecta, or excreta, of the body.
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Century Dictionary and Cyclopedia
    • ejecta Things that are cast out or away; refuse.
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Etymology

Webster's Revised Unabridged Dictionary
L., neut. pl. of ejectus, cast out. See Eject

Usage

In literature:

Nothing peculiar exists in the ejecta of morning sickness in pregnancy.
"A System of Practical Medicine by American Authors, Vol. I" by Various
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In news:

Instruments successfully captured each phase of the impact sequence — the impact flash, the ejecta plume, and the creation of the Centaur crater.
Of particular interest to scientists studying the geology of Mars are the ejecta of the smaller craters within Hadley.
With the impact that forms the craters , this ice would mix with surrounding materials to form a kind of "mud," which would then spread over the surface as ejecta.
Each element emits energy at some characteristic wavelengths as it decays , providing insight into the chemical composition of the supernova ejecta — the shells of material flung out by the exploding star.
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In science:

We find that GRB 98042 5 could plausibly have been produced by a collision between the relativistic ejecta from SN 1998bw and the star’s pre-supernova wind; the model requires no significant asymmetry.
Trans-Relativistic Supernovae, Circumstellar Gamma-Ray Bursts, and Supernova 1998bw
In this model, the energy that emerged as gamma rays was previously locked up in the kinetic energy of expanding ejecta.
Trans-Relativistic Supernovae, Circumstellar Gamma-Ray Bursts, and Supernova 1998bw
Another estimate of the minimum Lorentz factor, and one that does not depend on the specifics of the emission mechanism, arises from the requirement that 1048 ergs of gamma rays be produced in an interaction between stellar ejecta and the pre-supernova stellar wind.
Trans-Relativistic Supernovae, Circumstellar Gamma-Ray Bursts, and Supernova 1998bw
For mean ejecta Lorentz factor ¯G, the wind mass must be about 1/ ¯G of the ejecta mass.
Trans-Relativistic Supernovae, Circumstellar Gamma-Ray Bursts, and Supernova 1998bw
Although their formulae did not address relativistic motion, they were able to estimate the kinetic energy in relativistic ejecta by evaluating their formulae at a final velocity of c.
Trans-Relativistic Supernovae, Circumstellar Gamma-Ray Bursts, and Supernova 1998bw
Coupled with the minimum Lorentz factor identified above, this con firms Matzner & McKee’s prediction that SN 1998bw produced enough energy in relativistic ejecta to have powered GRB 980425.
Trans-Relativistic Supernovae, Circumstellar Gamma-Ray Bursts, and Supernova 1998bw
SN ejecta and/or to the density variation of the circumstellar medium.
Monitoring the Evolution of the X-ray Remnant of SN 1987A
The ejecta of these real jets, as seen from their emission point up to the point where they eventually stop and expand, generally subtend angles that decrease with time: just the opposite of the assumed behaviour of firetrumpets.
Optical and X-ray Afterglows in the Cannonball Model of GRBs
This is precisely where the density profile ought to be n ∝ r−2 , induced by the parent-star’s wind and ejecta.
Optical and X-ray Afterglows in the Cannonball Model of GRBs
The anisotropy of the neutrino- and shock-heated ejecta is growing in time and becomes very large due to an increasing contribution of the m = 0, l = 1 mode in the convective pattern.
Explosion Mechanisms of Massive Stars
Strong convection in the neutrino-heating region behind the supernova shock can account for huge anisotopies of the inner supernova ejecta, even without invoking rotation.
Explosion Mechanisms of Massive Stars
The idea that the energy transfer to the ejecta is mediated by neutrinos goes back to (Colgate & White 1966).
Explosion Mechanisms of Massive Stars
This may not be a serious problem if one recalls the large spread of energies of observed supernovae (Supernova 1999br, for example, is estimated to have an ejecta mass of 14 M⊙ and an explosion energy of about 6 × 1050 erg; Hamuy 2002).
Explosion Mechanisms of Massive Stars
Of course, final statements about explosion energy, ejecta composition, and the neutron star mass (which may change due to later fallback, especially when the explosion energy remains low) require to follow the evolution for a longer time.
Explosion Mechanisms of Massive Stars
In the case of the other (unresolved) epochs it is not clear whether the radio emission is from an unresolved jet, the nebula, spherical ejecta associated with the outburst or some combination.
A radio jet in the prototypical symbiotic star Z And?
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