H. R. Khan
- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Atomic and Subatomic Physics Research
- Particle Accelerators and Free-Electron Lasers
- Medical Imaging Techniques and Applications
- Radioactivity and Radon Measurements
- Geochemistry and Geologic Mapping
- Nuclear physics research studies
- Superconducting Materials and Applications
- Black Holes and Theoretical Physics
- Heavy metals in environment
- Computational Physics and Python Applications
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- Radioactive contamination and transfer
- Geochemistry and Elemental Analysis
- Optical Network Technologies
- Mine drainage and remediation techniques
- Nuclear and radioactivity studies
- Particle accelerators and beam dynamics
- Agricultural Science and Fertilization
- Peptidase Inhibition and Analysis
Khulna University
1999-2025
University of South Alabama
2023
University of Dhaka
2014-2021
King Saud University
2019-2020
Tokyo Institute of Technology
2004-2014
Princeton University
2008
Tokyo Metropolitan University
2005-2006
Chiba University
2006
The Graduate University for Advanced Studies, SOKENDAI
2006
Goethe University Frankfurt
2006
Rising soil pollution has recently emerged as a significant global issue result of increased industrialization, urbanization, and inadequate waste management. In Rampal Upazila, contamination with heavy metals resulted in deterioration quality life expectancy, so the study's goal is to appraise level metal samples. Inductively coupled plasma-optical emission spectrometry was used identify 13 (Al, Na, Cr, Co, Cu, Fe, Mg, Mn, Ni, Pb, Ca, Zn, K) from 17 samples that were collected at random...
We report the observation of a near-threshold enhancement in omegaJ/psi invariant mass distribution for exclusive B-->KomegaJ/psi decays. The results are obtained from 253 fb(-1) data sample that contains 275 x 10(6) BB pairs were collected near Upsilon(4S) resonance with Belle detector at KEKB asymmetric energy e(+)e(-) collider. statistical significance is estimated to be greater than 8sigma.
We report the first observation of a charmoniumlike state recoiling from J/psi in inclusive process e+e- -->J/psi+anything at mass (3.943+/-0.006+/-0.006) GeV/c{2}. also observe decay this into D*D[over ] and determine its intrinsic width to be less than 52 MeV/c{2} 90% C.L. These results are obtained 357 fb{-1} data sample collected with Belle detector near Upsilon(4S) resonance, KEKB asymmetric-energy collider.
We report the first observation of two charmed strange baryons that decay into Lambda(c)(+)Kappa(-)pi(+). The broader states is measured to have a mass 2978.5+/-2.1+/-2.0 MeV/c2 and width 43.5+/-7.5+/-7.0 MeV/c2. narrow state are be 3076.7+/-0.9+/-0.5 MeV/c;{2} 6.2+/-1.2+/-0.8 MeV/c2, respectively. also perform search for isospin partner Lambda(c)(+)Kappa(0)/(s)pi(-) observe significant signal at 3082.8+/-1.8+/-1.5 data used this analysis were accumulated or near Upsilon(4S) resonance, using...
The Collins effect connects transverse quark spin with a measurable azimuthal dependence in the yield of hadronic fragments around quark's momentum vector. Using two different reconstruction methods, we find evidence statistically significant asymmetries for charged pion pairs e(+)e(-) annihilation at center-of-mass energy 10.52 GeV, which can be attributed to polarization primordial quarks. measurement was performed using sample 79 x 10(6) events collected Belle detector.
We present an improved measurement of the branching fraction for electroweak penguin process $B\ensuremath{\rightarrow}{X}_{s}{\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$, where $\ensuremath{\ell}$ is electron or a muon and ${X}_{s}$ hadronic system containing $s$-quark. The based on sample $152\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $\ensuremath{\Upsilon}(4S)\ensuremath{\rightarrow}B\overline{B}$ events collected with Belle detector at KEKB energy asymmetric...
This pioneering study represents a comprehensive comparative analysis of naturally occurring radioactive materials (NORMs: 226Ra (≈238U),232Th, 40K) on the roadside dust samples collected from coastal city (Khulna) and highly urban megacity (Dhaka), Bangladesh. The corresponding radioactivity was calculated based Instrumental Neutron Activation Analysis elemental abundances (uranium [U], thorium [Th], potassium [K]). Averagen=30 levels (≈238U), 232Th, 40K in road Khulna were 46.82 ± 24,...
We report results on the Dalitz analysis of three-body charmless B+→K+π+π− and B+→K+K+K− decays based a 140 fb−1 data sample collected with Belle detector. Measurements branching fractions for quasi-two-body to scalar-pseudoscalar states: B+→f0(980)K+, B+→K∗0(1430)0π+, vector-pseudoscalar B+→K∗(892)0π+, B+→ρ0K+, B+→ϕK+ are presented. Upper limits some pseudoscalar-tensor final states reported. also measurement B+→χc0K+ fraction in two χc0 channels: χc0→π+π− χc0→K+K−.8 MoreReceived 23...
We present a new analysis of double charmonium production in e^+ e^- annihilation. The observation the processes -> J/psi eta_c, chi_c0, and eta_c(2S) is confirmed using dataset more than three times larger that Belle's previous report, no evidence for process found. perform an angular eta_c set upper limit on J/psi. Processes type psi(2S) (cc)_res have been observed first time; their rates are found to be comparable those processes.
We report the observation of an isotriplet excited charmed baryons, decaying into Lambda(+)(c)pi(-), Lambda(+)(c)pi(0), and Lambda(+)(c)pi(+). measure mass differences M(Lambda(+)(c)pi)-M(Lambda(+)(c)) widths to be 515.4(+3.2+2.1)(-3.1-6.0) MeV/c(2), 61(+18+22)(-13-13) MeV for neutral state; 505.4(+5.8+12.4)(-4.6-2.0) 62(+37+52)(-23-38) charged 514.5(+3.4+2.8)(-3.1-4.9) 75(+18+12)(-13-11) doubly state, where uncertainties are statistical systematic, respectively. These results obtained from...
We report results on a Dalitz analysis of three-body charmless ${B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{K}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}{\ensuremath{\pi}}^{\ensuremath{\mp}}$ decay including searches for direct $CP$ violation. the first observation ${B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{f}_{2}(1270){K}^{\ifmmode\pm\else\textpm\fi{}}$ with statistical significance above $6\ensuremath{\sigma}$. also...
We report a measurement of the exclusive e+e−→D(*)±D*∓ cross section as function center-of-mass energy near D(*)±D*∓ threshold with initial-state radiation. A partial reconstruction technique is used to increase efficiency and suppress background. The analysis based on data sample collected Belle detector an integrated luminosity 547.8 fb−1.Received 12 January 2007DOI:https://doi.org/10.1103/PhysRevLett.98.092001©2007 American Physical Society
We present improved measurements of $CP$-violation parameters in ${B}^{0}\ensuremath{\rightarrow}\ensuremath{\phi}{K}^{0}$, ${\ensuremath{\eta}}^{\ensuremath{'}}{K}^{0}$, ${K}_{S}^{0}{K}_{S}^{0}{K}_{S}^{0}$ decays based on a sample $535\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs collected at the $\ensuremath{\Upsilon}(4S)$ resonance with Belle detector KEKB energy-asymmetric ${e}^{+}{e}^{\ensuremath{-}}$ collider. obtain...
We present measurements of decay amplitudes and triple-product correlations in $B\ensuremath{\rightarrow}\ensuremath{\phi}{K}^{*}$ decays based on $253\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data recorded at the $\ensuremath{\Upsilon}(4S)$ resonance with Belle detector KEKB ${e}^{+}{e}^{\ensuremath{-}}$ storage ring. The for three different helicity states are determined from angular distributions final-state particles. longitudinal polarization found to be...
Using a $282\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data sample collected by the Belle experiment at KEKB ${e}^{+}{e}^{\ensuremath{-}}$ collider, we study ${D}^{0}$ decays to ${K}^{\ensuremath{-}}{\ensuremath{\ell}}^{+}\ensuremath{\nu}$ and ${\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\ell}}^{+}\ensuremath{\nu}$ final states. The flavor momentum are tagged through full reconstruction of recoiling charm meson additional mesons from fragmentation. method provides very good...
We report on a high statistics measurement of the cross section process $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ in ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ invariant mass range $0.8\text{ }\text{ }\mathrm{GeV}/{c}^{2}<W<1.5\text{ }\mathrm{GeV}/{c}^{2}$ with $85.9\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data collected at $\sqrt{s}=10.58\text{ }\mathrm{GeV}$ and 10.52 GeV Belle detector. A...
We report the results of several studies Lambda(c)(+)pi(+)pi(-)X final state in continuum e(+)e(-) annihilation data collected by Belle detector. An analysis angular distributions Lambda(c)(2880)(+)-->Sigma(c)(2455)(0,++)pi(+,-) decays strongly favors a Lambda(c)(2880)(+) spin assignment 5/2 over 3/2 or 1/2. find evidence for Lambda(c)(2880)(+)-->Sigma(c)(2520)(0,++)pi(+,-) decay and measure ratio partial widths Gamma(Sigma(c)(2520)pi)/Gamma(Sigma(c)(2455)pi)=0.225+/-0.062+/-0.025. This...
We present a measurement of the unitarity triangle angle ${\ensuremath{\phi}}_{3}$ using Dalitz plot analysis three-body decay neutral $D$ meson from ${B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{D}^{(*)}{K}^{\ifmmode\pm\else\textpm\fi{}}$ process. The method employs interference between ${D}^{0}$ and $\overline{{D}^{0}}$ to extract both weak strong phases. apply this $140\text{ }\text{ }{\mathrm{f}\mathrm{b}}^{\ensuremath{-}1}$ data sample collected by Belle experiment. uses...
We present an analysis of charm quark fragmentation at 10.6 GeV, based on a data sample $103\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ collected by the Belle detector KEKB accelerator. consider into main charmed hadron ground states, namely ${D}^{0},{D}^{+},{D}_{s}^{+}$ and ${\ensuremath{\Lambda}}_{c}^{+}$, as well excited states ${D}^{*0}$ ${D}^{*+}$. The functions are important to measure they describe processes low energy scale, where calculations in perturbation theory lead large...