arXiv subjects

M. S. Amjad

Publications and source records attributed to M. S. Amjad.

10 recordsLinked to original sources

arXiv2026

Probing Hard Scattering Processes via Multiple Weak Gauge Boson Production at the Future Colliders

One of the possible ways to detect the new physics phenomena particles is to investigate the weak gauge boson production as a result of hadron-hadron scattering. This study comprises the production of multiple weak gauge bosons as a result of hard scattering between the proton-proton beams at multi-TeV energies and integrated luminosity $\mathcal L =$ 3000 $fb ^{-1}$. The effective production cross-sections for pair, triple, and quartic scattering mechanisms have been computed as a function of $\sqrt s$. The center of mass energy has been varied from 8 TeV to 100 TeV to encompass the future collider capabilities. Out of all the studied processes, the triple scattering process $W^+W^-W^+$ has been chosen as the signal process based on the dominant cross-section. The background channels ZZZ, ZZZZ, $W^-ZZ$, $W^+ZZ$, $W^+W^-Z$, $W^+W^-ZZ$, $W^+W^-W^+W^-$, having comparatively lower cross-sections, have been selected from possible scattering mechanisms to investigate the effect of higher luminosity on the low production cross-section processes. We have investigated the different decay modes. For both lepton and hadron-specific decays of W and Z, the cumulative efficiencies for each signal and background process have been computed. In this study, we have successfully demonstrated an effective methodology for background suppression by systematically optimizing the signal-to-background ratio. The results indicate that, despite lower cross-sections for higher-order scattering, the distinct kinematic features enable effective signal isolation at future colliders.

hep-ph↗

arXiv2025

Exploring Charged Higgs at the Future Circular Collider (FCC): A Review of Two-Higgs-Doublet Models

This paper reports on the theoretical investigation of charged Higgs bosons and their coupling to fermions within the Two Higgs Doublet Model (THDM). The study focuses on the discovery potential of charged Higgs bosons predicted in Types III and IV at the future Circular Hadron-Hadron Collider (FCC-hh) with a center-of-mass energy of (\sqrt{s} = 100) TeV. By analyzing their decays, couplings to fermions, branching ratios, and production cross-section via (pp \rightarrow tH^-), we investigate the signatures of charged Higgs bosons, including kinematical distributions based on the background processes of (b\bar{b}) quarks.

hep-ph↗

arXiv2023

Observability of Parameter Space for Charged Higgs Boson in its bosonic decays in Two Higgs Doublet Model Type-1

This study explores the possibility of discovering $H^{\pm}$ through its bosonic decays, i.e. $H^{\pm}\rightarrow W^\pmϕ$ (where $ϕ$ = h or A), within the Type-I Two Higgs Doublet Model (2HDM). The main objective is to demonstrate the available parameter space after applying the recent experimental and theoretical exclusion limits. We suggest that for $m_{H^\pm}$ = 150 GeV is the most probable mass for the $H^\pm\rightarrow W^\pmϕ$ decay channel in $pp$ collisions at $\sqrt{s}$ = 8, 13 and 14 TeV. Therefore we propose that this channel may be used as an alternative to $H^\pm\rightarrow τ^\pmν$.

hep-ph↗

arXiv2023

Observability of triple top quark signal at Future Hadron Colliders

This paper is devoted to the Standard Model cross-sections for the production of single top, top quark in pairs, triple-top quarks, and four top-quarks at three different centre of mass-energies e.g., $\sqrt{s}=$7, 10 and 14 TeV at existing particle colliders as well as at Future Hadron Colliders. A fully kinemtaic analysis with the optimized pre-selection cuts along with invariant mass reconstruction of top quarks is performed for triple-top production processes pp$\rightarrow $tttW, tttd,tttb in the presence of Standard Model background. The three signal processes are forced to decay in fully hadronic mode and their significance is computed in High Luminosity Large Hadron Collider (HL$-$LHC) at $\sqrt{s}=$14 TeV and also in High-Energy LHC (HE$-$LHC) at $\sqrt{s}=$27 TeV. It is found that the observability at HL$-$LHC will would not be so easy task and chances are much lower but there are higher chances to observe the signal events at HE$-$LHC. The signal to background ratio and signal significance of all signal and background processes are estimated for both the HL$-$LHC and the HE$-$LHC at $\sqrt{s}$ =14 TeV and $\sqrt{s}$ =27 TeV respectively.

hep-ph↗

arXiv2019

Characterisation of different stages of hadronic showers using the CALICE Si-W ECAL physics prototype

A detailed investigation of hadronic interactions is performed using $π^-$-mesons with energies in the range 2--10 GeV incident on a high granularity silicon-tungsten electromagnetic calorimeter. The data were recorded at FNAL in 2008. The region in which the $π^-$-mesons interact with the detector material and the produced secondary particles are characterised using a novel track-finding algorithm that reconstructs tracks within hadronic showers in a calorimeter in the absence of a magnetic field. The principle of carrying out detector monitoring and calibration using secondary tracks is also demonstrated.

physics.ins-det↗

arXiv2019

EUDAQ2 -- A Flexible Data Acquisition Software Framework for Common Test Beams

The data acquisition software framework, EUDAQ, was originally developed to read out data from the EUDET-type pixel telescopes. This was successfully used in many test beam campaigns in which an external position and time reference were required. The software has recently undergone a significant upgrade, EUDAQ2, which is a generic, modern and modular system for use by many different detector types, ranging from tracking detectors to calorimeters. EUDAQ2 is suited as an overarching software that links individual detector readout systems and simplifies the integration of multiple detectors. The framework itself supports several triggering and event building modes. This flexibility makes test beams with multiple detectors significantly easier and more efficient, as EUDAQ2 can adapt to the characteristics of each detector prototype during testing. The system has been thoroughly tested during multiple test beams involving different detector prototypes. EUDAQ2 has now been released and is freely available under an open-source license.

physics.ins-det↗

arXiv2019

Summary and Conclusions of the 'JRA Beam Telescope 2025'-Forum at the 6th Beam Telescopes and Test Beams Workshop

On January 17th 2018, a forum on a possible Joint Research Activity on a future common Beam Telescope was held during the 6th Beam Telescopes and Test Beams Workshop (BTTB) in Zurich, Switzerland. The BTTB workshop aims at bringing together the community involved in beam tests. It therefore offers a suitable platform to induce community-wide discussions. The forum and its discussions were well received and the participants concluded that appropriate actions should be undertaken promptly. Specific hardware and software proposals were discussed, with an emphasis on improving current common EUDET-type telescopes based on Mimosa26 sensors towards higher trigger rate capabilities in convolution with considerably improved time resolution. EUDAQ as a common top level DAQ and its modular structure is ready for future hardware. EUTelescope fulfils many requirements of a common reconstruction framework, but has also various drawbacks. Thus, requirements for a new common reconstruction framework were collected. A new common beam telescope evolves with the sensor decision and the whole package including a reconstruction framework depends on that decision.

physics.ins-det↗

arXiv2015

A precise characterisation of the top quark electro-weak vertices at the ILC

Top quark production in the process $e^+e^- \to t\bar{t}$ at a future linear electron positron collider with polarised beams is a powerful tool to determine indirectly the scale of new physics. The presented study, based on a detailed simulation of the ILD detector concept, assumes a centre-of-mass energy of $\sqrt{s}=500\,$GeV and a luminosity of $\mathcal{L}=500\,{\rm fb}^{-1}$ equally shared between the incoming beam polarisations of $\mathcal{P}_{e^-}, \mathcal{P}_{e^+} =\pm0.8,\mp0.3$. Events are selected in which the top pair decays semi-leptonically and the cross sections and the forward-backward asymmetries are determined. Based on these results, the vector, axial vector and tensorial $CP$ conserving couplings are extracted separately for the photon and the $Z^0$ component. With the expected precision, a large number of models in which the top quark acts as a messenger to new physics can be distinguished with many standard deviations. This will dramatically improve expectations from e.g. the LHC for electro-weak couplings of the top quark.

hep-ex↗

arXiv2015

Testing Hadronic Interaction Models using a Highly Granular Silicon-Tungsten Calorimeter

A detailed study of hadronic interactions is presented using data recorded with the highly granular CALICE silicon-tungsten electromagnetic calorimeter. Approximately 350,000 selected negatively charged pion events at energies between 2 and 10 GeV have been studied. The predictions of several physics models available within the Geant4 simulation tool kit are compared to this data. A reasonable overall description of the data is observed; the Monte Carlo predictions are within 20% of the data, and for many observables much closer. The largest quantitative discrepancies are found in the longitudinal and transverse distributions of reconstructed energy.

physics.ins-det↗

arXiv2013

A precise determination of top quark electro-weak couplings at the ILC operating at $\roots=500\,\GeV$

Top quark production in the process $e^+e^- \rightarrow t\bar{t}$ at a future linear electron positron collider with polarised beams is a powerful tool to determine indirectly the scale of new physics. The presented study, based on a detailed simulation of the ILD detector concept, assumes a centre-of-mass energy of $\roots=500$\,GeV and a luminosity of $\mathcal{L}=500\,\invfb$ equality shared between the incoming beam polarisations of $P_{e^{-,+}} =\pm0.8,\mp0.3$. Events are selected in which the top pair decays semi-leptonically. The study comprises the cross sections, the forward-backward asymmetry and the slope of the helicity angle asymmetry. The vector, axial vector and tensorial CP conserving couplings are separately determined for the photon and the $Z^0$ component. The sensitivity to new physics would be dramatically improved with respect to what is expected from LHC for electroweak couplings.

hep-ex↗