19 Result(s)
within
Hsin-Chia Cheng
Elementary Particles, Quantum Field Theory
-
Article
Open AccessDark showers from Z-dark Z′ mixing
We discuss dark shower signals at the LHC from a dark QCD sector, containing GeV-scale dark pions. The portal with the Standard Model is given by the mixing of the Z boson with a dark Z′ coupled to the dark quark...
-
Article
Open AccessA theory of dark pions
We present a complete model of a dark QCD sector with light dark pions, broadly motivated by hidden naturalness arguments. The dark quarks couple to the Standard Model via irrelevant Z- and Higgs-portal operators...
-
Article
Open AccessA more natural composite Higgs model
Composite Higgs models provide an attractive solution to the hierarchy problem. However, many realistic models suffer from tuning problems in the Higgs potential. There are often large contributions from the U...
-
Article
Open AccessLight hidden mesons through the Z portal
Confining hidden sectors are an attractive possibility for physics beyond the Standard Model (SM). They are especially motivated by neutral naturalness theories, which reconcile the lightness of the Higgs with...
-
Article
Open AccessCoscattering/coannihilation dark matter in a fraternal twin Higgs model
Dark matter candidates arise naturally in many models that address the hierarchy problem. In the fraternal twin Higgs model which could explain the absence of the new physics signals at the Large Hadron Collid...
-
Article
Open AccessSinglet scalar top partners from accidental supersymmetry
We present a model wherein the Higgs mass is protected from the quadratic one-loop top quark corrections by scalar particles that are complete singlets under the Standard Model (SM) gauge group. While bearing ...
-
Article
Open AccessSecond stop and sbottom searches with a stealth stop
The top squarks (stops) may be the most wanted particles after the Higgs boson discovery. The searches for the lightest stop have put strong constraints on its mass. However, there is still a search gap in the...
-
Article
Open AccessStop search in the compressed region via semileptonic decays
In supersymmetric extensions of the Standard Model, the superpartners of the top quark (stops) play the crucial role in addressing the naturalness problem. For direct pair-production of stops with each stop de...
-
Article
Open AccessSame-sign dilepton excesses and vector-like quarks
Multiple analyses from ATLAS and CMS collaborations, including searches for ttH production, supersymmetric particles and vector-like quarks, observed excesses in the same-sign dilepton channel containing b-jets a...
-
Article
Open AccessExotic quarks in Twin Higgs models
The Twin Higgs model provides a natural theory for the electroweak symmetry breaking without the need of new particles carrying the standard model gauge charges below a few TeV. In the low energy theory, the o...
-
Article
Open AccessTop seesaw with a custodial symmetry, and the 126 GeV Higgs
The composite Higgs models based on the top seesaw mechanism commonly possess an enhanced approximate chiral symmetry, which is spontaneously broken to produce the Higgs field as the pseudo-Nambu-Goldstone bos...
-
Article
Open AccessHiggs mass from compositeness at a multi-TeV scale
Within composite Higgs models based on the top seesaw mechanism, we show that the Higgs field can arise as the pseudo Nambu-Goldstone boson of the broken U(3) L chiral symmetry ...
-
Article
A toolkit of the stop search via the chargino decay
The top squark (stop) may dominantly decay to a bottom quark and a chargino if the mass difference between the stop and the lightest neutralino is comparable or less than the top quark mass. Such a moderately ...
-
Article
A holographic model of heavy-light mesons
We construct a holographic model of heavy-light mesons by extending the AdS/QCD to incorporate the behavior of the heavy quark limit. In that limit, the QCD dynamics is governed by the light quark and the heav...
-
Article
Open AccessStop the top background of the stop search
The main background for the supersymmetric stop direct production search comes from Standard Model \( t\overline t \) events. For...
-
Article
Measuring invisible particle masses using a single short decay chain
We consider the mass measurement at hadron colliders for a decay chain of two steps, which ends with a missing particle. Such a topology appears as a subprocess of signal events of many new physics models whic...
-
Article
Open AccessIdentifying dark matter event topologies at the LHC
Assuming dark matter particles can be pair-produced at the LHC from cascade decays of heavy particles, we investigate strategies to identify the event topologies based on the kinematic information of final sta...
-
Article
Open AccessGoldstini as the decaying dark matter
We consider a new scenario for supersymmetric decaying dark matter without R-parity violation in theories with goldstini, which arise if supersymmetry is broken independently by multiple sequestered sectors. The ...
-
Article
Open AccessMissing momentum reconstruction and spin measurements at hadron colliders
We study methods for reconstructing the momenta of invisible particles in cascade decay chains at hadron colliders. We focus on scenarios, such as SUSY and UED, in which new physics particles are pair produced...
