Production of W and Z bosons accompanied by jets at LHC startup

Resummation of jet-veto logarithms in hadronic processes containing jets

We derive a factorization theorem for production of an arbitrary number of color-singlet particles accompanied by a fixed number of jets at the LHC. The jets are defined with the standard anti-$k_T$ algorithm, and the fixed number of jets is obtained by imposing a veto on additional radiation in the final state. The formalism presented here is useful for current Higgs boson analyses using exclusive jet bins, and for other studies using a similar strategy. The derivation uses the soft-collinear effective theory and assumes that the transverse momenta of the hard jets are larger than the veto sc…

Lepton Jets in (Supersymmetric) Electroweak Processes

We consider some of the recent proposals in which weak-scale dark matter is accompanied by a GeV scale dark sector that could produce spectacular lepton-rich events at the LHC. Since much of the collider phenomenology is only weakly model dependent it is possible to arrive at generic predictions for the discovery potential of future experimental searches. We concentrate on the production of dark states through $Z^0$ bosons and electroweak-inos at the Tevatron or LHC, which are the cleanest channels for probing the dark sector. We properly take into account the effects of dark radiation and dar…

Measurement of the top quark pair production cross section in pp collisions at sqrt(s) = 7 TeV in dilepton final states with ATLAS

A measurement of the production cross section of top quark pairs (ttbar) in proton-proton collisions at a center-of-mass energy of 7 TeV recorded with the ATLAS detector at the Large Hadron Collider is reported. Candidate events are selected in the dilepton topology with large missing transverse energy and at least two jets. Using a data sample corresponding to an integrated luminosity of 35 pb^-1, a ttbar production cross section of 171 +/- 20(stat.) +/- 14(syst.) +8-6(lum.) pb is measured for an assumed top quark mass of 172.5 GeV. A second measurement requiring at least one jet identified a…

Search for the Higgs boson in the all-hadronic final state using the CDF II detector

We report on a search for the production of the Higgs boson decaying to two bottom quarks accompanied by two additional quarks. The data sample used corresponds to an integrated luminosity of approximately 4\,\invfb\, of \ppbar\, collisions at $\sqrt{s}=1.96$\,TeV recorded by the CDF II experiment. This search includes twice the integrated luminosity of the previous published result, uses analysis techniques to distinguish jets originating from light flavor quarks and those from gluon radiation, and adds sensitivity to a Higgs boson produced by vector boson fusion. We find no evidence of the H…

Search for single production of vector-like quarks decaying to a Z boson and a top or a bottom quark in proton-proton collisions at sqrt(s) = 13 TeV

A search for single production of vector-like quarks, T and B, decaying into a Z boson and a top or a bottom quark, respectively, is presented. The search is performed using data collected by the CMS experiment at the LHC in proton-proton collisions at sqrt(s) = 13 TeV, corresponding to an integrated luminosity of 2.3 inverse femtobarns. An exotic T quark production mode through the decay of a heavy Z' resonance is also considered. The search is performed in events with a Z boson decaying leptonically, accompanied by a bottom or a top quark decaying hadronically. No excess of events is observe…

The Scope of the 4 tau Channel in Higgs-strahlung and Vector Boson Fusion for the NMSSM No-Lose Theorem at the LHC

We study the potential of the h_1 -> a_1 a_1 -> 4 tau signal from the lightest scalar (h_1) and pseudoscalar (a_1) Higgs bosons to cover the parameter space of the Next-to-Minimal Supersymmetric Standard Model (NMSSM) at the Large Hadron Collider (LHC). We exploit a 2 mu + 2 jets signature from four taus decays (accompanied by missing transverse energy), resorting to both Higgs-strahlung (HS), by triggering on leptonic W^\pm decays, and Vector Boson Fusion (VBF), by triggering on two same sign non-isolated muons.

13 TeV质子-质子碰撞中带电粒子喷注内部性质的多重数依赖性

Multiplicity dependence of charged-particle intra-jet properties in pp collisions at $\sqrt{s}$ = 13 TeV

本文首次测量13 TeV pp碰撞中领头带电粒子喷注内部性质的多重数依赖性，发现高多重数事件中低z^ch粒子碎裂增强、高z^ch抑制，PYTHIA 8可定性再现该修正，为喷注碎裂模型提供约束。

Search for anomalous gauge couplings in semi-leptonic decays of $WWγ$ and $WZγ$ in pp collisions at $\sqrt{s} =$ 8 TeV

A study of the Standard Model (SM) three electroweak boson production, $WVγ$ where V = W or Z gauge boson, is presented concerning events with a leptonically decaying W boson accompanied by a photon and two or more jets. We are using the full 2012 dataset, of proton-proton collisions at a center-of-mass energy of 8 TeV and an integrated luminosity of 19.3 fb${}^{-1}$, collected by the CMS detector at the Large Hadron Collider (LHC). $WVγ$ production final states may be sensitive to anomalous $WWγγ$ and $WWZγ$ quartic couplings. In light of the recent discovery of a Higgs-like particle, we inve…

在LHC上通过离壳标准模型类似希格斯玻色子探测长寿命标量粒子的对产生

Probing pair production of long-lived scalars via an off-shell Standard-Model-like Higgs boson at the LHC

研究通过离壳希格斯玻色子产生长寿命标量粒子对，利用ATLAS位移顶点搜索限制参数空间，并评估高亮度LHC的灵敏度提升。

Probing parton saturation and the gluon dipole via diffractive jet production at the Electron-Ion Collider

We demonstrate that hard dijet production via coherent inelastic diffraction is a promising channel for probing gluon saturation at the Electron-Ion Collider. By $inelastic$ diffraction we mean a process in which the two hard jets - a quark-antiquark pair generated by the decay of the virtual photon - are accompanied by a softer gluon jet, emitted by the quark or the antiquark. This process can be described as the elastic scattering of an effective gluon-gluon dipole. The cross section takes a factorised form, between a hard factor and a unintegrated ("Pomeron") gluon distribution describing t…