Shakeel Ahmad
A5014472904- High-Energy Particle Collisions Research
- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- Astrophysics and Cosmic Phenomena
- Particle Detector Development and Performance
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Nuclear reactor physics and engineering
- Nuclear physics research studies
- Radiation Detection and Scintillator Technologies
- Statistical Mechanics and Entropy
- Cosmology and Gravitation Theories
- Stochastic processes and statistical mechanics
- Atomic and Subatomic Physics Research
- Nuclear Physics and Applications
- Statistical Methods and Bayesian Inference
- Masonry and Concrete Structural Analysis
- Solar and Space Plasma Dynamics
- Structural Response to Dynamic Loads
- Theoretical and Computational Physics
- High-Velocity Impact and Material Behavior
- Radiation Therapy and Dosimetry
- Superconducting Materials and Applications
- Innovative concrete reinforcement materials
- Pulsars and Gravitational Waves Research
Aligarh Muslim University
2016-2025
Pakistan Institute of Nuclear Science and Technology
2020-2024
Southampton Solent University
2024
Sandwell & West Birmingham Hospitals NHS Trust
2024
Wuhan University
2024
University of Kashmir
2017-2023
Tata Institute of Fundamental Research
2017-2023
Indian Institute of Technology Kanpur
2019-2023
Dibrugarh University
2021-2023
Whipps Cross University Hospital
2023
ALICE (A Large Ion Collider Experiment) is a general-purpose, heavy-ion detector at the CERN LHC which focuses on QCD, strong-interaction sector of Standard Model. It designed to address physics strongly interacting matter and quark-gluon plasma extreme values energy density temperature in nucleus-nucleus collisions. Besides running with Pb ions, programme includes collisions lighter lower dedicated proton-nucleus runs. will also take data proton beams top collect reference for several QCD...
Elliptic flow from nuclear collisions is a hadronic observable sensitive to the early stages of system evolution. We report first results on elliptic charged particles at midrapidity in Au+Au square root(S)NN = 130 GeV using STAR Time Projection Chamber Relativistic Heavy Ion Collider. The signal, v2, averaged over transverse momentum, reaches values about 6% for relatively peripheral and decreases more central collisions. This can be interpreted as observation higher degree thermalization...
The pseudorapidity density of charged particles ($\mathrm{d}N_\mathrm{ch}/\mathrm{d}\eta$) at mid-rapidity in Pb-Pb collisions has been measured a center-of-mass energy per nucleon pair $\sqrt{s_{\rm NN}}$ = 5.02 TeV. It increases with centrality and reaches value $1943 \pm 54$ $|\eta|<0.5$ for the 5% most central collisions. A rise $\mathrm{d}N_\mathrm{ch}/\mathrm{d}\eta$ as function is observed, steeper than that observed proton-proton following trend established by measurements lower...
We report the first results of elliptic ($v_2$), triangular ($v_3$) and quadrangular flow ($v_4$) charged particles in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV with ALICE detector CERN Large Hadron Collider. The measurements are performed central pseudorapidity region $|\eta|<0.8$ for transverse momentum range $0.2<p_{\rm T}<5$ GeV/$c$. anisotropic is measured using two-particle correlations a gap greater than one unit multi-particle cumulant method. Compared to from NN}}=2.76$ TeV,...
The ALICE Collaboration reports unique data on particle production in Pb-Pb and inelastic $p$-$p$ collisions at the LHC 5.02 TeV. measurements range from very peripheral to most central collisions, cover particles with transverse momenta hundreds of MeV/$c$ 20 GeV/$c$. precision breadth provide tight constraints our understanding mechanisms these collisions.
Abstract One of the key challenges for nuclear physics today is to understand from first principles effective interaction between hadrons with different quark content. First successes have been achieved using techniques that solve dynamics quarks and gluons on discrete space-time lattices 1,2 . Experimentally, strong studied by scattering off each other. Such experiments are difficult or impossible unstable 3–6 so high-quality measurements exist only containing up down 7 Here we demonstrate...
Abstract The ALICE experiment was proposed in 1993, to study strongly-interacting matter at extreme energy densities and temperatures. This proposal entailed a comprehensive investigation of nuclear collisions the LHC. Its physics programme initially focused on determination properties quark–gluon plasma (QGP), deconfined state quarks gluons, created such collisions. has been extended cover broader ensemble observables related Quantum Chromodynamics (QCD), theory strong interactions. studied...
We report the measurements of correlations between event-by-event fluctuations amplitudes anisotropic flow harmonics in nucleus-nucleus collisions, obtained for first time using a new analysis method based on multiparticle cumulants mixed harmonics. This novel is robust against systematic biases originating from nonflow effects and by construction any dependence symmetry planes eliminated. demonstrate that exhibit better sensitivity to medium properties than individual The are performed...
The multi-strange baryon yields in PbPb collisions have been shown to exhibit an enhancement relative pp reactions. In this work, Ξ and Ω production rates measured with the ALICE experiment as a function of transverse momentum, pT, pPb at centre-of-mass energy sNN=5.02 TeV. results cover kinematic ranges 0.6 GeV/c<pT<7.2 GeV/c 0.8 GeV/c<pT<5 GeV/c, for respectively, common rapidity interval −0.5<yCMS<0. Multi-strange baryons identified by reconstructing their weak decays into charged...
The inclusive J/ψ production has been studied in Pb–Pb and pp collisions at the centre-of-mass energy per nucleon pair sNN=5.02 TeV, using ALICE detector CERN LHC. meson is reconstructed, rapidity interval 2.5<y<4 transverse-momentum range pT<12 GeV/c, via its decay to a muon pair. In this Letter, we present results on cross section s=5.02 TeV nuclear modification factor RAA. latter presented as function of centrality collision and, for central collisions, transverse momentum pT J/ψ....
The production of charged pions, kaons and (anti)protons has been measured at mid-rapidity ($-0.5 < y 0$) in p-Pb collisions $\sqrt{s_{\rm NN}}=5.02$ TeV using the ALICE detector LHC. Exploiting particle identification capabilities high transverse momentum ($p_{\rm T}$), previously published $p_{\rm T}$ spectra have extended to include measurements up 20 GeV/$c$ for seven event multiplicity classes. pp $\sqrt{s}=7$ TeV, needed interpolate a reference spectrum, also measure nuclear...
The production of K $$^{*}$$ (892) $$^{0}$$ and $$\phi $$ (1020) mesons has been measured in p–Pb collisions at $$\sqrt{s_{{\text {NN}}}}$$ $$=$$ 5.02 TeV. $$^{*0}$$ are reconstructed via their decay into charged hadrons with the ALICE detector rapidity range $$-0.5 <y <0$$ . transverse momentum spectra, as a function multiplicity, have p $$_{\mathrm {T}}$$ from 0 to 15 GeV/c for 0.3 21 Integrated yields, mean momenta particle ratios reported compared results pp $$\sqrt{s}$$ 7 TeV Pb–Pb 2.76...
This work presents new constraints on the existence and binding energy of a possible $\Lambda$-$\Lambda$ bound state, H-dibaryon, derived from femtoscopic measurements by ALICE collaboration. The results are obtained measurement using femtoscopy technique in pp collisions at $\sqrt{s}=13$ TeV p-Pb $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV, combined with previously published $\sqrt{s}=7$ TeV. scattering parameter space, spanned inverse length $f_0^{-1}$ effective range $d_0$, is constrained comparing...
We present the charged-particle pseudorapidity density in Pb–Pb collisions at sNN=5.02TeV centrality classes measured by ALICE. The measurement covers a wide range from −3.5 to 5, which is sufficient for reliable estimates of total number charged particles produced collisions. For most central (0–5%) we find 21400±1300, while peripheral (80–90%) 230±38. This corresponds an increase (27±4)% over results sNN=2.76TeV previously reported energy dependence heavy-ion found obey modified power-law...
A bstract We present the calibration strategy for 20 kton liquid scintillator central detector of Jiangmen Underground Neutrino Observatory (JUNO). By utilizing a comprehensive multiple-source and multiple-positional program, in combination with novel dual calorimetry technique exploiting two independent photosensors readout systems, we demonstrate that JUNO can achieve better than 1% energy linearity 3% effective resolution, required by neutrino mass ordering determination.
The prompt production of the charm baryon Λ_{c}^{+} and Λ_{c}^{+}/D^{0} ratios were measured at midrapidity with ALICE detector in pp p-Pb collisions sqrt[s_{NN}]=5.02 TeV. These new measurements show a clear decrease ratio increasing transverse momentum (p_{T}) both collision systems range 2<p_{T}<12 GeV/c, exhibiting similarities light-flavor baryon-to-meson p/π Λ/K_{S}^{0}. At low p_{T}, predictions that include additional color-reconnection mechanisms beyond leading-color approximation,...
JUNO is a multi-purpose neutrino observatory under construction in the south of China. This publication presents new sensitivity estimates for measurement $\Delta m^2_{31}$, m^2_{21}$, $\sin^2 \theta_{12}$, and \theta_{13}$ oscillation parameters using reactor antineutrinos, which one primary physics goals experiment. The sensitivities are obtained best knowledge available to date on location overburden experimental site, nuclear reactors surrounding area beyond, detector response...
The interaction of $\Lambda$ and $\Sigma$ hyperons (Y) with nucleons (N) is strongly influenced by the coupled-channel dynamics. Due to small mass difference $\rm N \Lambda$ \Sigma$ systems, sizeable coupling strength \Sigma\leftrightarrow processes constitutes a crucial element in determination N$\Lambda$ interaction. In this letter we present most precise measurements on p$\Lambda$ pairs, from zero relative momentum up opening channel. correlation function space for...
We study the polarization of inclusive J/ψ produced in Pb-Pb collisions at sqrt[s_{NN}]=5.02 TeV LHC dimuon channel, via measurement angular distribution its decay products. perform rapidity region 2.5<y<4, for three transverse momentum intervals (2<p_{T}<4, 4<p_{T}<6, 6<p_{T}<10 GeV/c) and as a function centrality collision 2<p_{T}<6 GeV/c. For first time, is measured with respect to event plane collision, by considering angle between positive-charge muon rest frame axis perpendicular...
The interaction of $\rm{K}^{-}$ with protons is characterised by the presence several coupled channels, systems like ${\rm \overline{K}^0}$n and $\pi\Sigma$ a similar mass same quantum numbers as $\rm{K}^{-}$p state. strengths these couplings to system are crucial importance for understanding nature $\Lambda(1405)$ resonance attractive strong interaction. In this article, we present measurements correlation functions in relative momentum space obtained pp collisions at $\sqrt{s}~=~13$ TeV,...
The production of the <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>ψ</a:mi><a:mo stretchy="false">(</a:mo><a:mn>2</a:mn><a:mi>S</a:mi><a:mo stretchy="false">)</a:mo></a:math> charmonium state was measured with ALICE in Pb-Pb collisions at <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:msqrt><e:msub><e:mi>s</e:mi><e:mrow><e:mi>NN</e:mi></e:mrow></e:msub></e:msqrt><e:mo>=</e:mo><e:mn>5.02</e:mn><e:mtext> </e:mtext><e:mtext>...