Gordon Research Seminar in Particle Physics: Pushing the Frontiers of Particle Physics During the LHC Run II Era

Session

Short oral presentations

24 Jun 2017, 16:30

Hong Kong University of Science and Technology (HKUST)

43. Interference Study on ttbb Final State by Monte Carlo Event Generation for a Heavy Higgs Search at the ATLAS Experiment at the LHC

Wing Yan Wong

24/06/2017, 16:30

At the LHC, particle physicists have been actively searching for more Higgs bosons, since the discovery of one, at 126 GeV, in 2012. The 126 GeV Higgs boson behaves like the Standard Model (SM) described. However, it is uncertain whether it is the SM Higgs or a SM-like Higgs among a larger Higgs sector in some beyond Standard Model (BSM) theories. The HKU ATLAS group is interested in the...

44. Probing 6D Higgs Operators at Future e^{+}e^{-} Colliders

Wen Han Chiu

24/06/2017, 16:35

In an effective theory, the UV physics can be parametrized by a set of higher-dimensional operators. We explore the sensitivity potential at future $e^-e^+$ colliders to probe six-dinmensional operators which may deform Higgs physics at electroweak scale. Different from studies in literature, we (1) analyze the sensitivities of disentangling the single-operator contribution, under the...

45. Optimizing Boosted Decision Trees for SUSY Searches at ATLAS

Gabriel Gallardo

24/06/2017, 16:40

With searches for new physics in the ATLAS experiment at the LHC, it is possible to encounter O(100000) background events compared to O(10) expected signal events. In the face of such challenging conditions, it can be difficult to do a traditional cut-based analysis to minimize background while still preserving reasonable signal efficiency such that the limits on new physics can be extended....

46. How Does Leptonic Collider Indirectly Probe Neutralino Dark Matter?

Huayong Han

24/06/2017, 16:45

We have calculated the one-loop effective action in the Standard Model dimension-6 operator basis by integrating out neutralinos and charginos in Minimal Supersymmetric Standard Model (MSSM) by using the Covariant Derivative Expansion (CDE) method. The results were verified by comparing the $h\gamma \gamma$ effective coupling from these effective operators and from loop calculation or low...

47. Six-top qurark channel phenomenon

Li Huang

24/06/2017, 16:50

Multi-top quark signal is very important in LHC, and the existing paper just analysis two or four top quarks channel. Six quark channel is sometimes important for it's search can shed light to top partner discovery. We want to give the constrains of six top quark of recent experiment and give some hints for experimentalist on how to find them.

48. Light Stops, Heavy Higgs, and Heavy Gluinos in Supersymmetric Standard Models with Extra Matters

Takumi Kuwahara

24/06/2017, 16:55

We have explored the possibilities of scenarios with heavy gluinos and light stops in supersymmetric (SUSY) standard models with extra vector-like multiplets. If we assume the hierarchical structure for soft masses of the minimal supersymmetric standard model (MSSM) scalar fields and extra scalars, the light stop and the observed Higgs boson can be realized. While the stau is the lightest SUSY...

49. The Maximally Symmetric Composite Higgs

Teng Ma

24/06/2017, 17:00

Maximal symmetry is a novel tool for composite pseudo-Goldstone boson Higgs models: it is a remnant of an enhanced global symmetry of the composite fermion sector involving a twisting with the Higgs field. Maximal symmetry has far-reaching consequences: it ensures that the Higgs potential is finite and fully calculable, and also minimizes the tuning.

50. Top FCNC (tcH) Simulation Through Monte Carlo Generators

Jia Shian Wang

24/06/2017, 17:05

At the LHC, physicists have been looking for additional scalar particles since the discovery of the SM Higgs. This project investigates in the behaviour of an additional neutral scalar particle (flavon), based on a cosmological beyond standard model (BSM) scenario (Froggatt-Nielsen model), through a top flavour changing neutral current (FCNC) process (tcH) simulated by Monte Carlo (MC)...

51. Electroweak monopoles and the electroweak phase transition

Suntharan Arunasalam

24/06/2017, 17:10

Electroweak monopoles are spherically symmetric configurations of the gauge fields that derive their stability from their topological nature. This talk discusses the effect of regularised Cho-Maison monopoles on the strength of the electroweak phase transition and the implications of this on electroweak baryogenesis.

52. Interpreting the 3 TeV WH resonance as a W' boson

Po-Yen Tseng

25/06/2017, 11:00

Motivated by a local 3.2-3.4 sigma resonance in WH and ZH in the ATLAS Run 2 data, we attempt to interpret the excess in terms of a W' boson in a SU(2)_1 \times SU(2)_2 \times U(1)_X model. We stretch the deviation from the alignment limit of the Equivalence Theorem, so as to maximize WH production while keeping the WZ production rate below the experimental limit. We found a viable though...

53. A Tale of Two Portals: Testing Light, Hidden New Physics at Future $e^+ e^-$ Colliders

Felix Yu

25/06/2017, 11:05

We investigate the prospects for producing new, light, hidden states at a future $e^+ e^-$ collider in a Higgsed dark $U(1)_D$ model, which we call the Double Dark Portal model. The simultaneous presence of both vector and scalar portal couplings immediately modifies the Standard Model Higgsstrahlung channel, $e^+ e^- \to Zh$, at leading order in each coupling. In addition, each portal leads...

54. Observation of a Baryonium Candidate at BES

Tianjue Min

25/06/2017, 11:10

Baryonium (proton-antiproton bound state) was predicted by theory long ago but not confirmed in experiment. In this talk, we will give a brief review of observation of a baryonium candidate at the BESII and BESIII experiments. Using 58 million J/psi decay events, the BESII experiment observed the proton-antiproton mass threshold enhancement X(ppbar) in J/psi->gamma p pbar and the X(1835) in...

55. Nonstandard neutrino interactions at the MOMENT

Yibing Zhang

25/06/2017, 11:15

The proposed MuOn-decay MEdium baseline NeuTrino beam experiment (MOMENT) is one of the neutrino experiments to measure the unknown 3-flavour frame parameter CP-violating phase. We consider the discovery reach of leptonic CP violation at MOMENT confronting with Non-standard neutrino Interactions (NSIs). We find that NSIs can induce bias in CP-violating phase measurements. We are able to...

56. The ALP miracle: unified inflaton and dark matter

Ryuji Daido

25/06/2017, 11:20

We propose a scenario where both inflation and dark matter are described by a single axion-like particle (ALP) in a unified manner. In a class of the minimal axion hilltop inflation, the effective masses at the maximum and mimimum of the potential have equal magnitude but opposite sign, so that the ALP inflaton is light both during inflation and in the true vacuum. After inflation, most of the...

57. Anomalous Triple Gauge Boson Coupling and Higgs Photoproduction Measurements at LHeC

Tao Xu

25/06/2017, 11:25

Understanding the electroweak sector of the Standard Model is one of the most important tasks in particle physics. We discuss its precise measurement at the proposed Large Hadron electron Collider(LHeC) with a focus on vector boson fusion processes. The first example is measuring charged anomalous triple gauge boson coupling(aTGC) in single W boson production process. Angular distributions of...

58. Probing the scale dependence of Non-Gaussianity through the CMB Spectral Distortion

Razieh Emami Meibogy

25/06/2017, 11:30

59. 3 Ways of Dark Matter Search at XMASS

Benda Xu

25/06/2017, 11:35

The XMASS program at Kamioka Observatory of Japan uses a self-shielding liquid xenon scintillator for the direct detection of dark matter and many other rare processes. The current running XMASS-I features 832kg ultra clean liquid xenon. Combined with low energy threshold of 0.3keV, XMASS-I is sensitive to low mass WIMPs and annual modulation search of dark matter.

60. New physics in multi-Higgs final states in 14 and 100 TeV colliders:

Sichun Sun

25/06/2017, 11:40

I am going to introduce how to parametrize the Standard Model and generic new-physics contributions by an effective Lagrangian that includes higher-dimensional operators. The selected subset of operators is motivated by composite-Higgs and Higgs-inflation models. The new physics effect can be potentially discovered in multi-Higgs final states in both 14 and future 100 TeV colliders.
In the...

61. Intermediate Mass Black Holes with Mirror Matter

Guido D'Amico

25/06/2017, 11:45

Mirror dark matter can potentially solve outstanding problems in structure formation, concerning the formation of small-scale structure on dwarf galaxy scales. We show that via its impact on residual ionization when early structure formation occurs, fragmentation into stars is naturally suppressed. The resulting formation of intermediate mass black holes in the mirror sector provides a new...

62. Increasing signal for Pulsar timing by two types of ultralight scalar axions

Hoang Nhan Luu

25/06/2017, 11:50

Pulsar timing array is an effective method to detect low-frequency gravitational waves. Khmelnitsky and Rubakov (2013) have proved that the oscillations in the arrival time could also be induced by the oscillations in pressure of ultralight scalar dark matter with mass around 10^{-22}. However, for simplicity, only one type of dark matter was taken into account. In this presentation, we...