Tracking down hyper-boosted top quarks

A Search for Boosted Top Quarks by CDF II

We present the results of a search for boosted top quarks in a sample of high transverse momentum jets observed in the CDF II detector. The data were selected from a sample of 5.95 fb−1 of 1.96 TeV proton-antiproton collisions at the Fermilab Tevatron. We observe 57 candidate events in a sample where we require two massive jets or one massive jet with significant missing transverse energy, with...

Studies of Highly-boosted Top Quarks Near the TeV Scale Using Jet Masses at the LHC

Measurement of the differential cross-section of highly boosted top quarks

The differential cross-section for pair production of top quarks with high transverse momentum is measured in 20.3 fb−1 of proton-proton collisions at a center-of-mass energy of 8 TeV. The measurement is performed for tt events in the leptonþ jets channel. The cross-section is reported as a function of the hadronically decaying top quark transverse momentum for values above 300 GeV. The hadroni...

Top-down causation without top-down causes

We argue that intelligible appeals to interlevel causes (top-down and bottom-up) can be understood, without remainder, as appeals to mechanistically mediated effects. Mechanistically mediated effects are hybrids of causal and constitutive relations, where the causal relations are exclusively intralevel. The idea of causation would have to stretch to the breaking point to accommodate interlevel ...

Top Quarks at Photon Colliders

A review of results on top quark physics expected at the Photon Linear Colliders is presented.