79 citations · 567 across the 32 of their papers we have counts for
35 papers
-trivial Galois cohomology classes and cohomological -dimension
Charles De Clercq
Given a prime , a field of characteristic different from and a finite -primary Galois module , a Galois cohomology class in is called -trivial if it…
Isotropic localizations of mixed initial motives
Charles De Clercq, Fabio Tanania
In this paper, we define the triangulated category of initial motives, which contains, for example, all motives of projective homogeneous varieties for semisimple algebraic groups…
Effective Bialynicki-Birula-Brosnan motivic decompositions
Charles De Clercq
Let be an isotropic reductive group and be a projective -homogeneous variety. Using results from Bialynicki-Birula, Hesselink and Iversen, Brosnan showed that if is…
A-upper motives of reductive groups
Charles De Clercq, Nikita Karpenko, Anne Quéguiner-Mathieu
Given a prime number , we perform the study of Chow motives and motivic decompositions, with coefficients in , of projective homogeneous varieties for $p…
Higher Tate traces of Chow motives
Charles De Clercq, Anne Quéguiner-Mathieu
We establish the complete classification of Chow motives of projective homogeneous varieties for -inner semi-simple algebraic groups, with coefficients in $\mathbb{Z}/p\mathbb{Z…
Smooth profinite groups, III: the Smoothness Theorem
Charles De Clercq, Mathieu Florence
Let be a prime. In this article, we prove the Smoothness Theorem, which asserts that a -cyclotomic pair is -cyclotomic, for all . In the particular case…
Smooth profinite groups, I: geometrizing Kummer theory
Charles De Clercq, Mathieu Florence
In this series of three papers, we introduce and study cyclotomic pairs and smooth profinite groups. They are a geometric axiomatisation of Kummer theory for fields, with coefficie…
Lifting low-dimensional local systems
Charles De Clercq, Mathieu Florence
Let be a field of characteristic . Denote by the ring of truntacted Witt vectors of length , built out of . In this text, we consider the following q…
Lifting vector bundles to Witt vector bundles
Charles De Clercq, Mathieu Florence, Giancarlo Lucchini Arteche
Let be a scheme. Let be an integer. Denote by the scheme of Witt vectors of length , built out of . We are concerned with the question of extending (=…
On the Tits p-indexes of semisimple algebraic groups
Charles De Clercq, Skip Garibaldi
The first author has recently shown that semisimple algebraic groups are classified up to motivic equivalence by the local versions of the classical Tits indexes over field extensi…
Upper motives of products of projective linear groups
Charles De Clercq
Fix a base field F, a finite field K and consider a sequence of central simple F-algebras A_1,...,A_n. In this note we provide some results toward a classification of the indecompo…
Motivic rigidity of Severi-Brauer varieties
Charles De Clercq
Let D be a central division algebra over a field F. We study in this note the rigidity of the motivic decompositions of the Severi-Brauer varieties of D, with respect to the ring o…
Study of the Dependence of Direct Soft Photon Production on the Jet Characteristics in Hadronic Z^0 Decays
DELPHI Collaboration, J. Abdallah
An analysis of the direct soft photon production rate as a function of the parent jet characteristics is presented, based on hadronic events collected by the DELPHI experiment at L…
Motivic decompositions of projective homogeneous varieties and change of coefficients
Charles De Clercq
We prove that under some assumptions on an algebraic group , indecomposable direct summands of the motive of a projective -homogeneous variety with coefficients in $\mathbb{F…
Measurements of CP-conserving Trilinear Gauge Boson Couplings WWV (V = gamma,Z) in e+e- Collisions at LEP2
The DELPHI Collaboration, J. Abdallah
The data taken by DELPHI at centre-of-mass energies between 189 and 209 GeV are used to place limits on the CP-conserving trilinear gauge boson couplings Delta_g1z, lambda_gamma an…
A going down theorem for Grothendieck Chow motives
Charles De Clercq
Let X be a geometrically split, geometrically irreducible variety over a field F satisfying Rost nilpotence principle. Consider a field extension E/F and a finite field K. We provi…
Search for single top production via FCNC at LEP at sqrt(s) = 189-208 GeV
The DELPHI Collaboration, J. Abdallah
A search for single top production (e+e- -> t cbar) via Flavour Changing Neutral Currents (FCNC) was performed using the data taken by the DELPHI detector at LEP2. The data analyse…
Search for B0_s - anti-B0_s oscillations in DELPHI using high-p_t leptons
The DELPHI Collaboration, J. Abdallah
Oscillations in the B0_s - anti-B0_s system were studied in events selected from about 4.3 million hadronic Z^0 decays registered by DELPHI between 1992 and 2000. This paper presen…
Determination of |Vub|/|Vcb| with DELPHI at LEP
The DELPHI Collaboration, P. Abreu
The ratio of the CKM quark-mixing matrix elements |Vub|/|Vcb| has been measured using B hadron semileptonic decays. The analysis uses the reconstructed mass M_X of the secondary ha…
Rapidity-Rank Structure of p pbar Pairs in Hadronic Z0 Decays
The DELPHI Collaboration, P. Abreu
The rapidity-rank structure of p pbar pairs is used to analyze the mechanism of baryon production in hadronic Z0 decay. The relative occurrence of the rapidity-ordered configuratio…
Measurement of V_{cb} from the decay process \bar{B^0} -> D^{*+} \ell^- \barν
The DELPHI Collaboration, P. Abreu
A new precise measurement of |V_{cb}| and of the branching ratio BR(\bar{B^0} -> D^{*+} \ell^- \bar{ν_\ell}) has been performed using a sample of about 5000 semileptonic decays \ba…
Search for charginos in e+e- interactions at sqrt(s) = 189 GeV
The DELPHI Collaboration, P. Abreu
An update of the searches for charginos and gravitinos is presented, based on a data sample corresponding to the 158 pb^{-1} recorded by the DELPHI detector in 1998, at a centre-of…
Search for Heavy Stable and Long-Lived Particles in e+e- Collisions at sqrt(s)=189 GeV
The DELPHI Collaboration, P. Abreu
A search for stable and long-lived heavy charged particles was performed using the data taken by the DELPHI experiment at an energy of 189 GeV. The Cherenkov light detected in the…
Measurement and Interpretation of Fermion-Pair Production at LEP Energies of 183 and 189 GeV
The DELPHI Collaboration, P. Abreu
An analysis of the data collected in 1997 and 1998 with the DELPHI detector at e+e- collision energies close to 183 and 189 GeV was performed in order to extract the hadronic and l…