The sputtering yield of typical impurity ions for different fusion reactor materials

Hechtl, E.; Bohdansky, J.; Roth, J.

doi:10.1016/0022-3115(82)90619-5

Cited by 74 publications

(14 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…(1) Bohdansky (1978); (2) Roth et al (1976); (3) Roth et al (1979); (4) Rosenberg & Wehner (1962); (5) Hechtl et al (1981); (6) Bach (1970); (7) Nenadović et al (1990); (8) Tielens et al (1994); (9) Behrisch et al (1976).…”

Section: Non-thermal Sputteringunclassified

Molecules and dust in Cassiopeia A

Biscaro

Cherchneff

2016

A&A

108

View full text Add to dashboard Cite

We study the dust evolution in the supernova remnant Cassiopeia A. We follow the processing of dust grains that formed in the Type II-b supernova ejecta by modelling the sputtering of grains. The dust is located in dense ejecta clumps that are crossed by the reverse shock. We also investigate further sputtering in the inter-clump medium gas once the clumps have been disrupted by the reverse shock. The dust evolution in the dense ejecta clumps of Type II-P supernovae and their remnants is also explored. We study oxygen-rich clumps that describe the oxygen core of the ejecta, and carbon-rich clumps that correspond to the outermost carbon-rich ejecta zone. We consider the various dust components that form in the supernova, several reverse shock velocities and inter-clump gas temperatures, and derive grain-size distributions and masses for the dust as a function of time. Both non-thermal sputtering within clumps and thermal sputtering in the inter-clump medium gas are studied. We find that non-thermal sputtering in the clumps is important for all supernova types and accounts for reducing the grain population by ∼40% to 80% in mass, depending on the clump gas over-density, the grain type and size, and the shock velocity in the clump. A Type II-b SN forms small grains that are sputtered within the clumps and in the inter-clump medium. For Cas A, silicate grains do not survive thermal sputtering in the inter-clump medium, while alumina, silicon carbide, and carbon dust may survive in the remnant. Our derived masses of currently processed silicate, alumina and carbon grains agree well with the values derived from the observations of warm dust, and seem to indicate that the dust is currently being processed within clumps by non-thermal sputtering. Out of the ∼0.03 M of dust formed in the ejecta, between 30% and 60% of this mass is present today in Cas A, and only 6% to 11% of the initial mass will survive the remnant phase. Grains formed in Type II-P supernovae are larger and better survive their journey in the remnant with mass fractions of surviving dust in the range 14−45%. For very dense ejecta, which describe the ejected material in supernovae such as SN1987A, non-thermal sputtering is inefficient within the clumps and dust survival efficiencies in the remnant range between 42% to 98% in mass. For the SN1987A model, the derived surviving dust mass is in the range ∼0.06−0.13 M . This type of supernovae with dense ejecta may then efficiently provide galaxies with dust. Specifically, silicate grains over 0.1 µm and other grains over 0, 05 µm survive thermal sputtering in the remnant. Therefore, pre-solar grains of supernova origin that are found in meteorites, in particular silicate and alumina grains, possibly form in the dense ejecta clumps of Type II-P supernovae.

show abstract

Section: Non-thermal Sputteringunclassified

Molecules and dust in Cassiopeia A

Biscaro

Cherchneff

2016

A&A

108

View full text Add to dashboard Cite

show abstract

“…The yields at 300 eV are summarized in Table I. They are to [30,31], O → C -calc. this work, He → C ▽ exp.…”

Section: B Erosion Of W Al Fe and Cmentioning

confidence: 99%

“…[30], He → Fe ---calc. [30], O → W • experimental [30,31,33], O → W • exp. this work, O → W -calculation [30], He → W ▽ exp.…”

Section: B Erosion Of W Al Fe and Cmentioning

confidence: 99%

Oxygen glow discharge cleaning in nuclear fusion devices

Hopf

Jacob

Rohde

2008

Journal of Nuclear Materials

View full text Add to dashboard Cite

Laboratory experiments were carried out as part of the preparations of an oxygen glow discharge cleaning experiment in ASDEX Upgrade. They aimed at evaluating the effect of mixing the oxygen with helium, the collateral damage caused by the glow discharge, as well as the influence of impurities in the films being eroded. Oxygen concentrations below 20 % in helium are sufficient to achieve high erosion rates. The discharge can lead to the formation of oxide layers on surfaces which-as demonstrated for tungsten-can be rapidly reduced by post-treatment in a hydrogen discharge. For carbon, aluminum and iron the physical sputtering yield may become similar to the erosion yield of redeposited layers, but it is by more than one order of magnitude smaller for tungsten. Using a-B:C:H films with varying boron content, it was found that impurities can cause the erosion rate to drop by orders of magnitude.

show abstract

“…The thermal oxygen radicals, atomic oxygen [16] and ozone [17], exhibit much higher reactivity at moderate temperatures, and there is indication that their reactivity toward a-C:H is still significant at room temperature. Bombardment of carbon with an oxygen ion beam leads to what is known as chemical sputtering or reactive ion etching [18][19][20]; in addition to physical sputtering the ions react chemically at the end of their range and form CO, CO 2 , and H 2 O, leading to highly enhanced sputtering yields and significantly lower threshold energies.…”

mentioning

confidence: 99%

Chemical sputtering of carbon films by argon ions and molecular oxygen at cryogenic temperatures

Hopf

Schlüter

Jacob

2007

Applied Physics Letters

View full text Add to dashboard Cite

The experiments demonstrate the existence of a synergistic interaction of molecular oxygen and energetic ions with amorphous carbon leading to enhanced erosion; although the samples, amorphous hydrogenated carbon films, are not gasified by O 2 at room temperature, additional ion bombardment at the same temperature leads to erosion rates that drastically exceed those of physical sputtering. Investigation of the temperature dependence from 400 down to 113 K shows that the erosion rate increases with decreasing temperature.

show abstract

The sputtering yield of typical impurity ions for different fusion reactor materials

Cited by 74 publications

References 9 publications

Molecules and dust in Cassiopeia A

Molecules and dust in Cassiopeia A

Oxygen glow discharge cleaning in nuclear fusion devices

Chemical sputtering of carbon films by argon ions and molecular oxygen at cryogenic temperatures

Contact Info

Product

Resources

About