J. Crnkovic
A5030409500- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Neutrino Physics Research
- Particle Detector Development and Performance
- Superconducting Materials and Applications
- Dark Matter and Cosmic Phenomena
- Muon and positron interactions and applications
- Particle Accelerators and Free-Electron Lasers
- Computational Physics and Python Applications
- Radiation Detection and Scintillator Technologies
- Atomic and Subatomic Physics Research
- Medical Imaging Techniques and Applications
- Nuclear physics research studies
- Black Holes and Theoretical Physics
- Astrophysics and Cosmic Phenomena
- Scientific Research and Discoveries
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum, superfluid, helium dynamics
- Atomic and Molecular Physics
- Particle accelerators and beam dynamics
- Advanced NMR Techniques and Applications
- Electron and X-Ray Spectroscopy Techniques
- Advanced MRI Techniques and Applications
- Cosmology and Gravitation Theories
Fermi National Accelerator Laboratory
2023-2024
University of Mississippi
2021-2022
Brookhaven National Laboratory
2015-2021
University of Illinois Urbana-Champaign
2007-2021
United States Department of Energy
2015
University of Illinois System
2011-2013
Campbell Collaboration
2012
We present the first results of Fermilab Muon g-2 Experiment for positive muon magnetic anomaly $a_\mu \equiv (g_\mu-2)/2$. The is determined from precision measurements two angular frequencies. Intensity variation high-energy positrons decays directly encodes difference frequency $\omega_a$ between spin-precession and cyclotron frequencies polarized muons in a storage ring. ring field measured using nuclear resonance probes calibrated terms equivalent proton spin precession...
We present a new measurement of the positive muon magnetic anomaly, a_{μ}≡(g_{μ}-2)/2, from Fermilab Muon g-2 Experiment using data collected in 2019 and 2020. have analyzed more than 4 times number positrons decay our previous result 2018 data. The systematic error is reduced by factor 2 due to better running conditions, stable beam, improved knowledge field weighted distribution, ω[over ˜]_{p}^{'}, anomalous precession frequency corrected for beam dynamics effects, ω_{a}. From ratio...
The Muon g-2 Experiment at Fermi National Accelerator Laboratory (FNAL) has measured the muon anomalous precession frequency $ω_a$ to an uncertainty of 434 parts per billion (ppb), statistical, and 56 ppb, systematic, with data collected in four storage ring configurations during its first physics run 2018. When combined a precision measurement magnetic field experiment's ring, determines anomaly $a_μ({\rm FNAL}) = 116\,592\,040(54) \times 10^{-11}$ (0.46 ppm). This article describes...
We present a measurement of angular observables, $P_4'$, $P_5'$, $P_6'$, $P_8'$, in the decay $B^0 \to K^\ast(892)^0 \ell^+ \ell^-$, where $\ell^+\ell^-$ is either $e^+e^-$ or $\mu^+\mu^-$. The analysis performed on data sample corresponding to an integrated luminosity $711~\mathrm{fb}^{-1}$ containing $772\times 10^{6}$ $B\bar B$ pairs, collected at $\Upsilon(4S)$ resonance with Belle detector asymmetric-energy collider KEKB. Four $P_{4,5,6,8}'$ are extracted five bins invariant mass...
A new experiment is described to detect a permanent electric dipole moment of the proton with sensitivity $10^{-29}e\cdot$cm by using polarized "magic" momentum $0.7$~GeV/c protons in an all-electric storage ring. Systematic errors relevant are discussed and techniques address them presented. The measurement sensitive physics beyond Standard Model at scale 3000~TeV.
The Fermi National Accelerator Laboratory has measured the anomalous precession frequency $a^{}_\mu = (g^{}_\mu-2)/2$ of muon to a combined precision 0.46 parts per million with data collected during its first physics run in 2018. This paper documents measurement magnetic field storage ring. is monitored by nuclear resonance systems and calibrated terms equivalent proton spin spherical water sample at 34.7$^\circ$C. weighted distribution resulting $\tilde{\omega}'^{}_p$, denominator ratio...
We present details on a new measurement of the muon magnetic anomaly, $a_\mu = (g_\mu -2)/2$. The result is based positive data taken at Fermilab's Muon Campus during 2019 and 2020 accelerator runs. uses $3.1$ GeV$/c$ polarized muons stored in $7.1$-m-radius storage ring with $1.45$ T uniform field. value $ a_{\mu}$ determined from measured difference between spin precession frequency its cyclotron frequency. This normalized to strength field, using Nuclear Magnetic Resonance (NMR). ratio...
The cross sections for ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\phi}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ and ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\phi}{f}_{0}(980)$ are measured from threshold to $\sqrt{s}=3.0\text{ }\text{ }\mathrm{GeV}$ using initial-state radiation. analysis is based on a data sample of $673\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ collected below the $\ensuremath{\Upsilon}(4S)$ resonance with Belle...
We report a measurement of the positive muon lifetime to precision 1.0 ppm; it is most precise particle ever measured. The experiment used time-structured, low-energy beam and segmented plastic scintillator array record more than 2×1012 decays. Two different stopping target configurations were employed in independent data-taking periods. combined results give τμ+(MuLan)=2 196 980.3(2.2) ps, 15 times as any previous experiment. gives value for Fermi constant: GF(MuLan)=1.166 378 8(7)×10−5...
We present a detailed report of the method, setup, analysis and results precision measurement positive muon lifetime. The experiment was conducted at Paul Scherrer Institute using time-structured, nearly 100%-polarized, surface beam segmented, fast-timing, plastic scintillator array. employed two target arrangements; magnetized ferromagnetic with ~4 kG internal magnetic field crystal quartz in 130 G external field. Approximately 1.6 x 10^{12} positrons were accumulated together data yield...
The differential cross section for the process $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}\ensuremath{\eta}{\ensuremath{\pi}}^{0}$ has been measured in kinematic range $0.84\text{ }\text{ }\mathrm{GeV}<W<4.0\text{ }\mathrm{GeV}$, $|\mathrm{cos}{\ensuremath{\theta}}^{*}|<0.8$, where $W$ and ${\ensuremath{\theta}}^{*}$ are energy ${\ensuremath{\pi}}^{0}$ (or $\ensuremath{\eta}$) scattering angle, respectively, $\ensuremath{\gamma}\ensuremath{\gamma}$ center-of-mass system....
We report the first measurement of $D^{\ast -}$ meson polarization in decay $B^0 \to D^{*-} \tau^+\nu_{\tau}$ using full data sample 772$\times 10^6$ $B\bar{B}$ pairs recorded with Belle detector at KEKB electron-positron collider. Our result, $F_L^{D^\ast} = 0.60 \pm 0.08 ({\rm stat}) 0.04 sys})$, where $F_L^{D^\ast}$ denotes $D^{\ast-}$ longitudinal fraction, agrees within about $1.7$ standard deviations model prediction.
The precise determination of the CKM matrix element $\left| V_{cb}\right|$ is important for carrying out tests flavour sector Standard Model. In this article we present a preliminary analysis $\bar B^0 \to D^{*\,+} \, \ell^- \bar ν_\ell$ decay mode and its charge conjugate, selected in events that contain fully reconstructed $B$-meson, using 772 million $e^+ e^- Υ(4S) B B$ recorded by Belle detector at KEKB. Unfolded differential rates four kinematic variables describing $B$-meson rest frame...
We present a new measurement of the positive muon magnetic anomaly, $a_\mu \equiv (g_\mu - 2)/2$, from Fermilab Muon $g\!-\!2$ Experiment using data collected in 2019 and 2020. have analyzed more than 4 times number positrons decay our previous result 2018 data. The systematic error is reduced by factor 2 due to better running conditions, stable beam, improved knowledge field weighted distribution, $\tilde{\omega}'^{}_p$, anomalous precession frequency corrected for beam dynamics effects,...
The mean life of the positive muon has been measured to a precision 11 ppm using low-energy, pulsed beam stopped in ferromagnetic target, which was surrounded by scintillator detector array. result, tau(micro)=2.197 013(24) micros, is excellent agreement with previous world average. new average 019(21) micros determines Fermi constant G(F)=1.166 371(6)x10(-5) GeV-2 (5 ppm). Additionally, measurement positive-muon lifetime needed determine nucleon pseudoscalar coupling g(P).
We report the first measurement of $τ$ lepton polarization in decay ${\bar B} \rightarrow D^* τ^- {\barν_τ}$ as well a new ratio branching fractions $R(D^{*}) = \mathcal{B}({\bar {\barν_τ}) / \ell^- {\barν_{\ell}})$, where $\ell^-$ denotes an electron or muon, with decays $τ^- π^- ν_τ$ and ρ^- ν_τ$. use full data sample $772 \times 10^6$ $B{\bar B}$ pairs accumulated Belle detector at KEKB electron-positron collider. Our preliminary results, $R(D^*) 0.276 \pm 0.034{\rm (stat.)} ^{+0.029}...
We report preliminary results on the analysis of three-body Y(10860)=> B barB pi, Y(10860) => (B barB* + c.c.) pi and B* decays including an observation Zb(10610)+- pi-+ [B barB*+c.c]+- Zb(10650)+- [B* barB*]+- as intermediate channels. measure branching fractions to be Br(Y(10860)=> barB*+c.c.]+- pi-+)=(28.3+-2.9+-4.6)x10^{-3} pi-+)=(14.1+-1.9+-2.4)x10^{-3} set 90% C.L. upper limit barB]+- pi-+)<4.0x10^{-3}. also amplitude Y(10860)=>Y(nS)pi+pi-, n=1,2,3 internal structure...
We report the observation of two narrow structures at 10610MeV/c^2 and 10650MeV/c^2 in pi^{\pm}Upsilon(nS) (n=1,2,3) pi^{\pm}h_b(mP) (m=1,2) mass spectra that are produced association with a single charged pion Upsilon(5S) decays. The measured masses widths averaged over five final states M_1=10608.4\pm2.0MeV/c^2, Gamma_1=15.6\pm2.5MeV M_2=10653.2\pm1.5MeV/c^2, Gamma_2=14.4\pm3.2MeV. Analysis favors quantum numbers I^G(J^P)=1^+(1^+) for both states. results obtained 121.4fb^{-1} data sample...
The anomalous magnetic moment of the muon is one most precisely measured quantities in experimental particle physics. Its latest measurement at Brookhaven National Laboratory deviates from Standard Model expectation by approximately 3.5 standard deviations. goal new experiment, E989, now under construction Fermilab, a fourfold improvement precision. Here, we discuss details future and its current status.
Received 7 February 2011DOI:https://doi.org/10.1103/PhysRevLett.106.079901© 2011 American Physical Society
We report a measurement of the time-integrated $CP$ asymmetry in neutral charm meson decay $D^0 \to K^0_S K^0_S$ using 921~fb$^{-1}$ data collected at $Υ(4S)$ and $Υ(5S)$ resonances with Belle detector KEKB asymmetric-energy $e^+e^-$ collider. The observed is $$ A_{CP}(D^0 K^0_S) = (-0.02 \pm 1.53 0.17) \%, where first uncertainty statistical second systematic. This latter dominated by error normalisation channel. result consistent Standard Model expectations improves respect to previous...