Weak-lensing Mass Reconstruction of Galaxy Clusters with a Convolutional Neural Network

We introduce a novel method for reconstructing the projected matter distributions of galaxy clusters with weak-lensing (WL) data based on a convolutional neural network (CNN). Training data sets are generated with ray-tracing through cosmological simulations. We control the noise level of the galaxy shear catalog such that it mimics the typical properties of the existing ground-based WL observations of galaxy clusters. We find that the mass reconstruction by our multilayered CNN with the architecture of alternating convolution and trans-convolution filters significantly outperforms the traditional reconstruction methods. The CNN method provides better pixel-to-pixel correlations with the truth, restores more accurate positions of the mass peaks, and more efficiently suppresses artifacts near the field edges. In addition, the CNN mass reconstruction lifts the mass-sheet degeneracy when applied to our projected cluster mass estimation from sufficiently large fields. This implies that this CNN algorithm can be used to measure the cluster masses in a model-independent way for future wide-field WL surveys.

Light Higgs searches in $$ t\overline{t}\phi $$ production at the LHC

In this paper we propose a new reconstruction method to explore the low mass region in the associated production of top-quark pairs ($$ t\overline{t} $$ t t ¯ ) with a generic scalar boson (ϕ) at the LHC. The new method of mass reconstruction shows an improved resolution of at least a factor of two in the low mass region when compared to previous methods, without the loss of sensitivity of previous analyses. It turns out that it also leads to an improvement of the mass reconstruction of the 125 GeV Higgs for the same production process. We use an effective Lagrangian to describe a scalar with a generic Yukawa coupling to the top quarks. A full phenomenological analysis was performed, using Standard Model background and signal events generated with MadGraph5_aMC@NLO and reconstructed using a kinematic fit. The use of CP-sensitive variables allows then to maximize the distinction between CP-even and CP-odd components of the Yukawa couplings. Confidence Levels (CLs) for the exclusion of ϕ bosons with mixed CP (both CP-even and CP-odd components) were determined as a function of the top Yukawa couplings to the ϕ boson. The mass range analysed starts slightly above the ϒΥ mass up to 40 GeV, although the analysis can be used for an arbitrary mass. If no new light scalar is found, exclusion limits at 95% CL for the absolute value of the CP-even and CP-odd Yukawa are derived. Finally, we analyse how these limits constrain the parameter space of the complex two-Higgs doublet model (C2HDM).

Socio-economic prerequisites for reconstruction of residential buildings of the first mass series

The article considers normative-legal, town-planning, technical and technological aspects of the problem of deployment of mass reconstruction and modernization of large-block residential buildings of the first mass series. Analysis and generalization of practical experience in the design and implementation of mass reconstruction of residential buildings of the first mass series in Ukraine and abroad shows that with the introduction of innovative approaches to the design of spatial planning and design solutions, application of modern and well-established technologies for their reconstruction economic, resource-saving, energy-saving, environmental protection and architectural and aesthetic benefits. The analysis of modern researches testifies to expediency of introduction of methods of reconstruction. An important aspect of mass reconstruction is the economic attractiveness for investors, this parameter is most widely discussed in this article. It is also important that the moral obsolescence of the building began much earlier than the physical, and the needs of people and the requirements for comfort increased significantly, which suggests the need for mass reconstruction of buildings of the first mass series. The condition for the deployment of mass reconstruction and modernization of large residential buildings of the first mass series is a comprehensive justification of its social, urban, regulatory and technological feasibility, as well as economic attractiveness for investors. This provision is taken as the task of this article. Analysis and generalization of normative-legal, social and technological aspects of reconstruction of large-block residential buildings of the first mass series and practical experience of designing and implementation of such reconstruction are accepted as the main research methods. On the example of the city of Chernivtsi the scheme of building of the city was developed and the percentage of building by buildings of the first mass series was calculated. This allows you to pay attention to the mass nature of the issue.

Mass Reconstruction of MSSM Higgs Boson

The problems of the Standard Model, as well as questions related to Higgs boson properties led to the need to model the ttH associated production and the Higgs boson decay to a top quark pair within the MSSM model. With the help of computer programs MadGraph, Pythia, and Delphes and using the latest kinematic cuts taken from experimental data obtained at the LHC, we have predicted the masses of MSSM Higgs bosons, A and H.

Analysis of a Single-Λ Hypernuclear Event in KEK-PS E373 Nuclear Emulsion Experiment

The purpose of this research is to identify a single-Λ hypernucleus and its decay products which support to get more information about hyperon-nucleon interaction. Before performing the analysis of a single-Λ hypernucleus, first, we have deduced the density of emulsion by calibrating the range-energy relation using alpha decay events data from thorium series. It is very important for the mass reconstruction of hypernucleus events in nuclear emulsion. And we have reconstructed a single-Λ hypernucleus event by using the kinematical reconstruction for mesonic and non-mesonic decay modes. From the result of our analysis, we can uniquely identify that single-Λ hypernucleus is $ {}_\Lambda ^9 B $ and decay products are 4He,3He, proton and neutron.