Publications

Order by: publication date number of citations

Pair production of charged IDM scalars at high energy CLIC

Jan Klamka

SciPost Phys. Proc. 8, 097 (2022) · published 13 July 2022 | · pdf

The Compact Linear Collider (CLIC) was proposed as the next energy-frontier infrastructure at CERN, to study e$^+$e$^-$ collisions at three centre-of-mass energy stages: 380 GeV, 1.5 TeV and 3 TeV. The main goal of its high-energy stages is to search for the new physics beyond the Standard Model (SM). The Inert Doublet Model (IDM) is one of the simplest SM extensions and introduces four new scalar particles: H$^\pm$, A and H; the lightest, H, is stable and hence a natural dark matter (DM) candidate. A set of benchmark points is considered, which are consistent with current theoretical and experimental constraints and promise detectable signals at future colliders. Prospects for observing pair-production of the IDM scalars at CLIC were previously studied using signatures with two leptons in the final state. In the current study, discovery reach for the IDM charged scalar pair-production is considered for the semi-leptonic final state at the two high-energy CLIC stages. Full simulation analysis, based on the current CLIC detector model, is presented for five selected IDM scenarios. Results are then extended to the larger set of benchmarks using the Delphes fast simulation framework. The CLIC detector model for Delphes has been modified to take pile-up contribution from the beam-induced $\gamma\gamma$ interactions into account, which is crucial for the presented analysis. Results of the study indicate that heavy, charged IDM scalars can be discovered at CLIC for most of the proposed benchmark scenarios, with very high statistical significance.
Production mechanisms of open heavy flavor mesons in high-multiplicity events

Marat Siddikov, Ivan Schmidt

SciPost Phys. Proc. 8, 096 (2022) · published 13 July 2022 | · pdf

In this proceeding we discuss different mechanisms of open-heavy flavor meson production which contribute to inclusive and single diffractive cross-sections. For the case of inclusive production we demonstrate that the three-Pomeron fusion is significant for the $D$-meson production in the kinematics of small transverse momenta $p_{T}$, as well as in large-multiplicity events. Its inclusion allows to improve significantly the description of experimental data. We also analyzed the diffractive production and found that due to gap survival factors it constitutes 0.5\textendash 2 per cent of the inclusive production. The expected dependence on event multiplicity in this channel is significantly milder than for inclusive case.
Dark matter searches with mono-photon signature at future e$^+$e$^-$ colliders

Jan Kalinowski, Wojciech Kotlarski, Krzysztof Mekala, Pawel Sopicki, Aleksander Filip Zarnecki

SciPost Phys. Proc. 8, 095 (2022) · published 13 July 2022 | · pdf

As any e$^+$e$^-$ scattering process can be accompanied by a hard photon emission from the initial state radiation, the analysis of the energy spectrum and angular distributions of those photons can be used to search for hard processes with an invisible final state. Thus high energy e$^+$e$^-$ colliders offer a unique possibility for the most general search of Dark matter based on the mono-photon signature. We consider production of DM particles via a mediator at the International Linear Collider (ILC) and Compact Linear Collider (CLIC) experiments taking into account detector effects within the DELPHES fast simulation framework. Limits on the light DM production in a generic model are set for a wide range of mediator masses and widths. For mediator masses up to the centre-of-mass energy of the collider, results from the mono-photon analysis are more stringent than the limits expected from direct resonance searches in Standard Model decay channels.

2 citations
DsTau: study of tau neutrino production with nuclear emulsion in the CERN-SPS

Ali Murat Guler

SciPost Phys. Proc. 8, 094 (2022) · published 13 July 2022 | · pdf

Tau neutrino is one of the least known particle of Standard Model; there are only few measurements with a limited statistics. The DONUT experiment first reported the tau neutrino interaction cross-section but their measurement suffers from large systematic error of more than $50\%$ which is mainly due to uncertainty in the tau neutrino flux prediction. The tau neutrino cross section is an essential ingredient in neutrino experiments and its precise measurement would enable a search for new physics effects such as testing the Lepton Universality in neutrino interactions. The main goal of the DsTau experiment is to measure an inclusive differential cross-section of a $D_s$ production with a consecutive decay to tau lepton in p-A interactions at the CERN-SPS. The measurement of DsTau will reduce the systematic uncertainty in tau neutrino interaction cross-section to $10\%$ level. The results from the pilot run and the prospect for physics runs in 2021-2022 will be discussed.
Probing proton PDFs at high x with LHCb

Thomas Boettcher

SciPost Phys. Proc. 8, 093 (2022) · published 13 July 2022 | · pdf

LHCb is a forward spectrometer at the LHC covering the pseudorapidity region $2<\eta<5$. Because of this forward coverage, LHCb can probe the proton parton distribution functions (PDFs) in previously unexplored kinematic regimes, in particular at very high and low Bjorken-$x$. This contribution presents LHCb measurements that can be used to constrain the proton PDFs, with a focus on the high-$x$ and high-$Q^2$ regime.
Studies of $b$-hadrons and quarkonia at LHCb

Zhiyu Xiang

SciPost Phys. Proc. 8, 092 (2022) · published 13 July 2022 | · pdf

LHCb has productive studies of quarkonia and $b$-hadrons which provide essential inputs to study quantum chromodynamics (QCD). In this proceeding, seven recent results are reported: the observation of a new excited $\Xi_b^0$ resonance in $\Xi_b^- \pi^+$ final states, the new excited $B_s^0$ state is observed in $B^+ K^-$ mass spectrum, the first observation of suppressed semileptonic $B_s^0 \rightarrow K^- \mu^+ \nu_{\mu}$ decay, the first observation of the decay $B^0 \rightarrow D^0 \bar{D}^0 K^+ \pi^-$, the first observation of the Cabibbo-suppressed decay $\Lambda_b^0 \rightarrow \chi_{c1} p \pi^-$, the first observation of $\Lambda_b^0 \rightarrow \Lambda_c^+ K^+ K^- \pi^-$ decay, and end this report with the first search for the doubly heavy baryon $\Omega_{bc}^{0}$ and a search for $\Xi_{bc}^0$ baryon.
Searches for invisible scalar decays at CLIC

Krzysztof Mekala, Aleksander Filip Zarnecki, Bohdan Grzadkowski, Michal Iglicki

SciPost Phys. Proc. 8, 091 (2022) · published 13 July 2022 | · pdf

The Compact Linear Collider (CLIC) is a proposed TeV-scale high-luminosity electron-positron collider at CERN. The first CLIC running stage, at 380 GeV, will focus on precision Higgs boson and top quark studies while the main aim of the subsequent high-energy stages, at 1.5 TeV and 3 TeV, is to extend the sensitivity of CLIC to different Beyond the Standard Model (BSM) scenarios. We studied the prospects for measuring invisible Higgs boson and additional heavy scalar decays using CLIC data at 380 GeV and 1.5 TeV. The analysis is based on the WHIZARD event generator, with fast simulation of the CLIC detector response parametrised by the DELPHES package. We present the expected limits for the invisible decays of the 125 GeV Higgs boson, the cross section limits for production of an additional neutral Higgs scalar, assuming its invisible decays, and limits on the mixing angle between the SM-like Higgs boson and the new scalar of the "dark sector" in the framework of the vector-fermion dark matter model.

1 citation
Longitudinal double helicity asymmetry $A_{LL}$ from direct photon, jet and charged pion production in polarized $\vec{p}+\vec{p}$ collisions

Zhongling Ji

SciPost Phys. Proc. 8, 090 (2022) · published 13 July 2022 | · pdf

Understanding the proton spin composition from the quarks and gluons spin polarization and their motion is important to test various kinds of sum rules and nonperturbative properties of hadrons. At the Relativistic Heavy Ion Collider (RHIC), we collide longitudinally polarized proton beams and measure the double helicity asymmetry $A_{LL}$, which is an important physical quantity for extracting the polarized parton distribution functions (PDFs) of the proton. Direct photon, jet and charged pion production are good channels to probe the gluon spin polarization inside the proton, with the ability to probe also the sign of the gluon spin. Direct photon production is the theoretically ``cleanest'' channel, with little fragmentation contribution, but limited by statistics. On the other hand, jet and charged pion production have more statistics, but include more hard processes and hadronization effects. I will present the recent measurements of direct photon, jet and charged pion $A_{LL}$s at PHENIX and show their complementary roles in extracting the gluon spin.
Exclusive emissions of rho-mesons and the unintegrated gluon distribution

Andrèe Dafne Bolognino, Francesco Giovanni Celiberto, Dmitry Yu. Ivanov, Alessandro Papa

SciPost Phys. Proc. 8, 089 (2022) · published 13 July 2022 | · pdf

Exclusive emissions of vector mesons in forward directions of rapidity offer us a faultless chance to probe the proton structure at small-$x$. A high-energy factorization formula is established within BFKL, given as the convolution of an impact factor depicting the forward-meson emission and of an unintegrated gluon distribution (UGD) driving the gluon evolution at small-$x$. As a nonperturbative quantity, the UGD is not well known and several models for it exist. We present recent progresses on the study of the exclusive forward $\rho$-meson leptoproduction at HERA and EIC energies, showing how osbervables sensitive to different polarization states of the $\rho$-particle act as discriminators for the existing UGD models.

6 citations
LUXE: A new experiment to study non-perturbative QED in $e^{-}$-laser and $γ$-laser collisions

Ruth Jacobs

SciPost Phys. Proc. 8, 088 (2022) · published 13 July 2022 | · pdf

The LUXE experiment (Laser Und XFEL Experiment) is a new experiment in planning at DESY Hamburg using the electron beam of the European XFEL. LUXE is intended to study collisions between a high-intensity optical laser and up to 16.5 GeV electrons from the Eu.XFEL electron beam, or, alternatively, high-energy secondary photons. The physics objective of LUXE are processes of Quantum Electrodynamics (QED) at the strong-field frontier, where QED is non-perturbative. This manifests itself in the creation of physical electron-positron pairs from the QED vacuum. LUXE intends to measure the positron production rate in a new physics regime at an unprecedented laser intensity. Parasitically, the high-intensity Compton photon beam of LUXE can be used to search for physics beyond the Standard Model.

1 citation

Previous 1 ... 4 5 6 7 8 9 10 11 12 13 14 ... 18 Next

Publications

2 citations

1 citation

6 citations

1 citation