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- Abazov, V. M., et al.
(författare)
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The upgraded DO detector
- 2006
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 565:2, s. 463-537
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Tidskriftsartikel (refereegranskat)abstract
- The DO experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has been upgraded to take advantage of improvements to the Tevatron and to enhance its physics capabilities. We describe the new elements of the detector, including the silicon microstrip tracker, central fiber tracker, solenoidal magnet, preshower detectors, forward muon detector, and forward proton detector. The uranium/liquid -argon calorimeters and central muon detector, remaining from Run 1, are discussed briefly. We also present the associated electronics, triggering, and data acquisition systems, along with the design and implementation of software specific to DO.
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| 2. |
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| 3. |
- Feary, David A., et al.
(författare)
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Trophic ecology of New Zealand triplefin fishes (Family Tripterygiidae)
- 2009
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Ingår i: Marine Biology. - : Springer Science and Business Media LLC. - 0025-3162 .- 1432-1793. ; 156:8, s. 1703-1714
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Tidskriftsartikel (refereegranskat)abstract
- In many vertebrate radiations, food partitioning among closely related taxa is a key factor in both the maintenance of species diversity and the process of diversification. We compared diet composition and jaw morphology of 18 New Zealand triplefin species (F. Tripterygiidae) to examine whether species have diversified along a trophic axis. These fishes predominantly utilised small, mobile benthic invertebrates, and interspecific differences in diet composition appeared to be mainly attributable to habitat- or size-dependent feeding behaviour. Although there were differences in the relative size of the bones comprising the oral jaw apparatus between species, the majority showed an apparatus consistent with a relatively high velocity, low force jaw movement indicative of a diet of evasive prey. Phylogenetic comparative analyses showed that the evolution of jaw lever ratios and diet breadth was best explained by a non-directional model in which character changes have occurred randomly and independent of phylogeny. The mode of diet breadth evolution was gradual and the tempo has not accelerated or slowed down over time. The mode of evolution for the jaw lever ratios has been gradual for the opening but punctuated for the closing levers, suggesting that evolutionary changes have occurred rapidly for the latter trait. The tempo of trait evolution for the jaw opening levers has not accelerated or slowed down over time, while the tempo for the jaw closing levers has accelerated towards the tips of the tree, which is suggestive of species level adaptation. The lack of phylogenetic signal in diet breadth and jaw lever ratios appears most likely to be a correlated response to the marked habitat diversification in this group, and is thus the passive outcome of prey availability in species-specific habitat types. Overall, the trophic ecology of New Zealand's triplefin fauna parallels the generalist strategy typical of the family worldwide, suggesting that trophic resource partitioning has not been an important factor in the evolution of these fishes.
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