相关论文: Stop searches in flavourful supersymmetry
Many new physics models that explain the intriguing anomalies in the $b$-quark flavour sector are severely constrained by $B_s$-mixing, for which the Standard Model prediction and experiment agreed well until recently. The most recent FLAG…
In this work, we study the light stop pair signals at the LHC. We explore the SUSY parameter space with non-universal gaugino and third generation masses at the GUT scale. Recent LHC SUSY search results based on 35pb$^{-1}$ and 1fb$^{-1}$…
The symmetry of the superconducting order parameter, or simply the ``gap'', provides certain constraints on the actual mechanism that gives rise to pairing and ultimately to superconductivity. In this work we show how superconducting phases…
The experiments at the LHC are searching for many different final states that can hint to the presence of new physics beyond the Standard Model. One of the most interesting and promising sectors for these searches is that of the top quark,…
Leptoquarks have recently received much attention especially because they may provide an explanation to the $R_{D^{(*)}}$ and $R_{K^{(*)}}$ anomalies in rare $B$ meson decays. In a previous paper we proposed a systematic search strategy for…
Gluinos that result in classic large missing transverse momentum signatures at the LHC have been excluded by 2011 searches if they are lighter than around 800 GeV. This adds to the tension between experiment and supersymmetric solutions of…
Stop squarks with a mass just above the top's and which decay to a nearly massless LSP are difficult to probe because of the large SM di-top background. Here we discuss search strategies which could be used to set more stringent bounds in…
We show that a novel decay mode $Zh$ of the bound state of stop-anti-stop pair in the ground state $^1S_0(\widetilde t_1\widetilde t_1^*)$ may have a significant branching ratio if the $CP$ violating mixing appears in the stop sector, even…
If low-energy supersymmetry is realized in nature, a seemingly contrived hierarchy in the squark mass spectrum appears to be required. We show that composite supersymmetric theories at the bottom of the conformal window can automatically…
We show that a right-handed stop in the 200-400 GeV mass range, together with a nearly degenerate neutralino and, possibly, a gluino below 1.5 TeV, follows from reasonable assumptions, is consistent with present data, and offers interesting…
In the search for bottom squark (sbottom) in SUSY at the LHC, the common practice has been to assume a $100\%$ decay branching fraction for a given search channel. In realistic MSSM scenarios, there are often more than one significant decay…
Effective Supersymmetry is presented as a theory of physics above the electroweak scale which has significant theoretical advantages over both the standard model and the Minimal Supersymmetric Standard Model (MSSM). The theory is…
We investigate the effects of hidden matter condensation on supersymmetry breaking in supergravity models derived from free fermionic strings. We find that the minimum of the effective potential in the modulus direction depends strongly on…
Simple extensions of the Standard Model (SM) with additional Right Handed Neutrinos (RHNs) can elegantly explain the existence of small neutrino masses and their flavor mixings. Collider searches for sterile neutrinos are being actively…
We analyse a simple Standard Model (SM) extension with only two new light fields: a scalar partner of the top (stop) (with mass above m_t) and a light neutral fermion chi^0 (with mass of a few GeV), coupled to SM quarks via a Yukawa…
Searches for supersymmetry (SUSY) at the LHC frequently assume the conservation of $R$-parity in their design, optimization and interpretation. In the case that $R$-parity is not conserved, constraints on SUSY particle masses tend to be…
In supersymmetry (SUSY) the flavor mixing between top-squark (stop) and charm-squark (scharm) induces the flavor-changing neutral-current (FCNC) stop decay $\tilde t_1 \to c \tilde \chi^0_1$. Searching for this decay serves as a probe of…
We analyze possible interpretations of the recent LHCb evidence for CP violation in D meson decays in terms of physics beyond the Standard Model. On general grounds, models in which the primary source of flavor violation is linked to the…
Top squark (stop) is a crucial part of supersymmetric models (SUSY) to understand the naturalness problem. Other than the traditional stop pair production, the single production via electroweak interaction provides signals with distinctive…
We design a search strategy for the Standard Model $t\bar t t \bar t$ production at the LHC in the same-sign dilepton and trilepton channels. We study different signal features and, given the small expected number of signal events, we…