A. Shaikhiev
A5077751311- Particle physics theoretical and experimental studies
- Neutrino Physics Research
- Quantum Chromodynamics and Particle Interactions
- Astrophysics and Cosmic Phenomena
- Dark Matter and Cosmic Phenomena
- High-Energy Particle Collisions Research
- Computational Physics and Python Applications
- Particle Detector Development and Performance
- Muon and positron interactions and applications
- Atomic and Subatomic Physics Research
- Particle accelerators and beam dynamics
- Radiation Detection and Scintillator Technologies
- Nuclear Physics and Applications
- Cosmology and Gravitation Theories
- Particle Accelerators and Free-Electron Lasers
- Medical Imaging Techniques and Applications
- Black Holes and Theoretical Physics
- Quantum, superfluid, helium dynamics
- Pulsars and Gravitational Waves Research
- Methane Hydrates and Related Phenomena
- Antenna Design and Analysis
- Advanced Optical Sensing Technologies
- Wireless Body Area Networks
- Atomic and Molecular Physics
- Superconducting Materials and Applications
UCLouvain
2019-2024
Roma Tre University
2024
University of Birmingham
2023-2024
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati
2024
Institute for Nuclear Research
2013-2023
University of California, Irvine
2021-2023
University of Bern
2023
Albert Einstein College of Medicine
2023
Eötvös Loránd University
2023
Boston University
2021-2023
A bstract The NA62 experiment reports the branching ratio measurement $$ \mathrm{BR}\left({K}^{+}\to {\pi}^{+}\nu \overline{\nu}\right)=\left({10.6}_{-3.4}^{+4.0}\left|{}_{\mathrm{stat}}\right.\pm {0.9}_{\mathrm{syst}}\right)\times {10}^{-11} <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>BR</mml:mi> <mml:mfenced> <mml:mrow> <mml:msup> <mml:mi>K</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mo>→</mml:mo> <mml:mi>π</mml:mi> <mml:mi>ν</mml:mi> <mml:mover> <mml:mo>¯</mml:mo>...
Evidence of a heavy neutrino, $\nu_H$, in the $K^+\to\mu^+\nu_H$ decays was sought using E949 experimental data with an exposure $1.70\times 10^{12}$ stopped kaons. With major background from radiative $K^+\to\mu^+\nu_\mu\gamma$ decay understood and suppressed, upper limits (90% C.L.) on neutrino mixing matrix element between muon $|U_{\mu H}|^2$, were set at level $10^{-7}$ to $10^{-9}$ for mass region 175 300 MeV/$c^2$.
A search for heavy neutral lepton (N) production in K+→e+N decays using the data sample collected by NA62 experiment at CERN 2017–2018 is reported. Upper limits of extended neutrino mixing matrix element |Ue4|2 are established level 10−9 over most accessible mass range 144–462 MeV/c2, with assumption that lifetime exceeds 50 ns. These improve significantly upon those previous and decay searches. The favoured Big Bang Nucleosynthesis excluded up to a about 340 MeV/c2.
The NA62 experiment at CERN reports searches for $K^+\to\mu^+N$ and $K^+\to\mu^+\nu X$ decays, where $N$ $X$ are massive invisible particles, using the 2016-2018 data set. particle is assumed to be a heavy neutral lepton, results expressed as upper limits of ${\cal O}(10^{-8})$ neutrino mixing parameter $|U_{\mu4}|^2$ masses in range 200-384 MeV/$c^2$ lifetime exceeding 50 ns. considered scalar or vector hidden sector mediator decaying an final state, decay branching fraction 10-370 reported...
The calorimeter, range detector and active target elements of the T2K near detectors rely on Hamamatsu Photonics Multi-Pixel Photon Counters (MPPCs) to detect scintillation light produced by charged particles. Detailed measurements MPPC gain, afterpulsing, crosstalk, dark noise, photon detection efficiency for low levels are reported. In order account impact behavior physics observables, a simulation program has been developed based these measurements. is used predict energy resolution detector.
The results of a search for $\pi^0$ decays to photon and an invisible massive dark at the NA62 experiment CERN SPS are reported. From total $4.12\times10^8$ tagged mesons, no signal is observed. Assuming kinetic-mixing interaction, limits set on coupling ordinary as function mass, improving previous searches in mass range 60--110 MeV/$c^2$. present interpreted terms upper limit branching ratio electro-weak decay $\pi^0 \to \gamma \nu \overline{\nu}$, current by more than three orders magnitude.
A bstract The NA62 experiment at the CERN SPS reports a study of sample 4 × 10 9 tagged π 0 mesons from K + → ( γ ), searching for decay to invisible particles. No signal is observed in excess expected background fluctuations. An upper limit . − set on branching ratio 90% confidence level, improving previous results by factor 60. This result can also be interpreted as model- independent X , where particle escaping detection with mass range 0.110–0.155 GeV /c 2 and rest lifetime greater than...
A sample of 3984 candidates the K+→π+γγ decay, with an estimated background 291±14 events, was collected by NA62 experiment at CERN during 2017–2018. In order to describe observed di-photon mass spectrum, next-to-leading contribution in chiral perturbation theory found be necessary. The decay branching ratio full kinematic range is measured (9.61±0.17)×10−7. first search for production and prompt axion-like particle gluon coupling process K+→π+a, a→γγ also reported.
A bstract search for the K + → π X decay, where is a long-lived feebly interacting particle, performed through an interpretation of $$ {\pi}^{+}\nu \overline{\nu} <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>π</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mi>ν</mml:mi> <mml:mover> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> analysis data collected in 2017 by NA62 experiment at CERN. Two ranges masses, 0–110 MeV /c 2 and 154–260 , lifetimes above 100 ps are...
A bstract The NA62 experiment reports an investigation of the $$ {K}^{+}\to {\pi}^{+}\nu \overline{\nu} <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>K</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mo>→</mml:mo> <mml:mi>π</mml:mi> <mml:mi>ν</mml:mi> <mml:mover> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> mode from a sample K + decays collected in 2017 at CERN SPS. has achieved single event sensitivity (0 . 389 ± 0 024) × 10 − , corresponding to 2.2 events...
Searches for lepton number violating K+→π−e+e+ and K+→π−π0e+e+ decays have been performed using the complete dataset collected by NA62 experiment at CERN in 2016–2018. Upper limits of 5.3×10−11 8.5×10−10 are obtained on decay branching fractions 90% confidence level. The former result improves a factor four over previous best limit, while latter represents first limit rate.
A bstract sample of 1 . 3 × 10 5 K + → π 0 e νγ candidates with less than 1% background was collected by the NA62 experiment at CERN SPS in 2017–2018. Branching fraction measurements are obtained percent relative precision three restricted kinematic regions, improving on existing results a factor larger two. An asymmetry, possibly related to T-violation, is investigated no evidence observed within achieved precision.
A sample of $2.8 \times 10^4$ $K^{+} \to \pi^{+} \mu^{+} \mu^{-}$ candidates with negligible background was collected by the NA62 experiment at CERN SPS in 2017--2018. The model-independent branching fraction is measured to be $(9.15 \pm 0.08)\times 10^{-8}$, a factor three more precise than previous measurements. decay form presented as function squared dimuon mass. measurement parameters and their uncertainties performed using description based on Chiral Perturbation Theory $\mathcal{O}(p^6)$.
A search for the $K^+\to\mu^-\nu e^+e^+$ decay, forbidden within Standard Model by either lepton number or flavour conservation depending on of emitted neutrino, has been performed using dataset collected NA62 experiment at CERN in 2016--2018. An upper limit $8.1\times 10^{-11}$ is obtained decay branching fraction 90% CL, improving a factor 250 over previous search.
A bstract The NA62 experiment at CERN targets the measurement of ultra-rare $$ {K}^{+}\to {\pi}^{+}\nu \overline{\nu} <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>K</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:mo>→</mml:mo> <mml:mi>π</mml:mi> <mml:mi>ν</mml:mi> <mml:mover> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> decay, and carries out a broad physics programme that includes probes for symmetry violations searches exotic particles. Data were collected in...
Evidence of the $K^+\to\mu^+\nu\bar\nu\nu$ decay was searched for using E949 experimental data with an exposure $1.70\times 10^{12}$ stopped kaons. The sample is dominated by backgrond process $K^+\to\mu^+\nu_\mu\gamma$. An upper limit on rate $\Gamma(K^+\to\mu^+\nu\bar\nu\nu)< 2.4\times 10^{-6}\Gamma(K^+\to all)$ at 90% confidence level set assuming Standard Model muon spectrum. are presented in such a way as to allow calculation rates any assumed $\mu^+$
The first search for ultra-rare K+ decays into the π+e+e−e+e− final state is reported, using a dataset collected by NA62 experiment at CERN in 2017–2018. An upper limit of 1.4×10−8 90% CL obtained branching ratio K+→π+e+e−e+e− decay, predicted Standard Model to be (7.2±0.7)×10−11. Upper limits are level 10−9 ratios two prompt decay chains involving pair-production hidden-sector mediators: K+→π+aa, a→e+e− and K+→π+S, S→A′A′, A′→e+e−.
A sample of 2.8⇥10 4 K + !⇡ µ candidates with negligible background was collected by the NA62 experiment at CERN SPS in 2017-2018.The model-independent branching fraction is measured to be (9.15 ± 0.08) ⇥ 10 8 , a factor three more precise than previous measurements.The decay form presented as function squared dimuon mass.A measurement parameters and their uncertainties performed using description based on Chiral Perturbation Theory O(p 6 ).