K. Jakovčić
A5102791895- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Dark Matter and Cosmic Phenomena
- Particle Detector Development and Performance
- Neutrino Physics Research
- Astrophysics and Cosmic Phenomena
- Quantum Chromodynamics and Particle Interactions
- Cosmology and Gravitation Theories
- Computational Physics and Python Applications
- Atomic and Subatomic Physics Research
- Particle Accelerators and Free-Electron Lasers
- Solar and Space Plasma Dynamics
- Particle accelerators and beam dynamics
- Advanced Frequency and Time Standards
- Radiation Detection and Scintillator Technologies
- Black Holes and Theoretical Physics
- Superconducting Materials and Applications
- Distributed and Parallel Computing Systems
- Astronomy and Astrophysical Research
- Scientific Research and Discoveries
- Geophysics and Gravity Measurements
- Laser-Plasma Interactions and Diagnostics
- Aerodynamics and Acoustics in Jet Flows
- Industrial Automation and Control Systems
- Experimental Learning in Engineering
Rudjer Boskovic Institute
2015-2025
A. Alikhanyan National Laboratory
2024
Institute of High Energy Physics
2024
University of Antwerp
2024
University of Patras
2019
European Organization for Nuclear Research
2016
University of Bonn
2015
National Centre of Scientific Research "Demokritos"
2015
Joint Institute for Nuclear Research
2015
Institute for Development and International Relations
2012
A bstract The OPERA neutrino experiment at the underground Gran Sasso Laboratory has measured velocity of neutrinos from CERN CNGS beam over a baseline about 730 km. measurement is based on data taken by in years 2009, 2010 and 2011. Dedicated upgrades timing system detector, as well high precision geodesy campaign for baseline, allowed reaching comparable systematic statistical accuracies. An arrival time muon with respect to one computed assuming speed light vacuum $ \left( {6.5\pm...
A bstract The OPERA neutrino experiment is designed to perform the first observation of oscillations in direct appearance mode ν μ → τ channel, via detection -leptons created charged current interactions. detector, located underground Gran Sasso Laboratory, consists an emulsion/lead target with average mass about 1.2 kt, complemented by electronic detectors. It exposed CERN Neutrinos beam, a baseline 730 km and mean energy 17 GeV. candidate event analysis 2008-2009 sample have been reported...
We have searched for solar axions or similar particles that couple to two photons by using the CERN Axion Solar Telescope (CAST) setup with improved conditions in all detectors. From absence of excess X-rays when magnet was pointing Sun, we set an upper limit on axion-photon coupling 8.8 x 10^{-11} GeV^{-1} at 95% CL m_a <~ 0.02 eV. This result is best experimental over a broad range axion masses and eV also supersedes previous derived from energy-loss arguments globular-cluster stars.
The International Axion Observatory (IAXO) will be a forth generation axion helioscope. As its primary physics goal, IAXO look for axions or axion-like particles (ALPs) originating in the Sun via Primakoff conversion of solar plasma photons. In terms signal-to-noise ratio, about 4–5 orders magnitude more sensitive than CAST, currently most powerful helioscope, reaching sensitivity to axion-photon couplings down few × 10−12 GeV−1 and thus probing large fraction unexplored ALP parameter space....
We have searched for solar axions or other pseudoscalar particles that couple to two photons by using the CERN Axion Solar Telescope (CAST) setup. Whereas we previously reported results from CAST with evacuated magnet bores (Phase I), setting limits on lower mass axions, here report where were filled 4He gas II) of variable pressure. The introduction generates a refractive photon mγ, thereby achieving maximum possible conversion rate those axion masses ma match mγ. With 160 different...
The OPERA neutrino detector in the underground Gran Sasso Laboratory (LNGS) has been designed to perform first detection of oscillations direct appearance mode through study $\nu_\mu\rightarrow\nu_\tau$ channel. hybrid apparatus consists an emulsion/lead target complemented by electronic detectors and it is placed high energy long-baseline CERN LNGS beam (CNGS) 730 km away from source. Runs with CNGS neutrinos were successfully carried out 2008 2009. After a brief description beam,...
The CERN Axion Solar Telescope (CAST) has extended its search for solar axions by using 3He as a buffer gas. At T=1.8 K this allows larger pressure settings and hence sensitivity to higher axion masses than our previous measurements with 4He. With about 1 h of data taking at each 252 different we have scanned the mass range 0.39 eV < m_a 0.64 eV. From absence excess X-rays when magnet was pointing Sun set typical upper limit on axion-photon coupling g_ag 2.3 x 10^{-10} GeV^{-1} 95% CL, exact...
The OPERA experiment was designed to search for $\nu_{\mu} \rightarrow \nu_{\tau}$ oscillations in appearance mode, i.e. by detecting the $\tau$-leptons produced charged current $\nu_{\tau}$ interactions. took data from 2008 2012 CERN Neutrinos Gran Sasso beam. observation of appearance, achieved with four candidate events a sub-sample data, previously reported. In this paper, fifth event, found an enlarged sample, is described. Together further reduction expected background, detected so far...
We study the feasibility of a new generation axion helioscope, most ambitious and promising detector solar axions to date. show that large improvements in magnetic field volume, x-ray focusing optics backgrounds are possible beyond those achieved CERN Axion Solar Telescope (CAST). For hadronic models, sensitivity axion-photon coupling gaγ ≳ few × 10−12 GeV−1 is conceivable, 1–1.5 orders magnitude CAST sensitivity. If also couple electrons, Sun produces larger flux for same value Peccei-Quinn...
The CERN Axion Solar Telescope has finished its search for solar axions with (3)He buffer gas, covering the range 0.64 eV ≲ ma 1.17 eV. This closes gap to cosmological hot dark matter limit and actually overlaps it. From absence of excess x rays when magnet was pointing Sun we set a typical upper on axion-photon coupling gaγ 3.3 × 10(-10) GeV(-1) at 95% C.L., exact value depending pressure setting. Future direct axion searches will focus increasing sensitivity smaller values gaγ, example by...
We review the physics potential of a next generation search for solar axions: International Axion Observatory (IAXO) . Endowed with sensitivity to discover axion-like particles (ALPs) coupling photons as small gaγ∼ 10−12 GeV−1, or electrons gae∼10−13, IAXO has find QCD axion in 1 meV∼1 eV mass range where it solves strong CP problem, can account cold dark matter Universe and be responsible anomalous cooling observed number stellar systems. At same time, will have enough detect lower axions...
The OPERA experiment was designed to study ν_{μ}→ν_{τ} oscillations in the appearance mode CERN Gran Sasso Neutrino beam (CNGS). In this Letter, we report final analysis of full data sample collected between 2008 and 2012, corresponding 17.97×10^{19} protons on target. Selection criteria looser than previous analyses have produced ten ν_{τ} candidate events, thus reducing statistical uncertainty measurement oscillation parameters properties. A multivariate approach for event identification...
A bstract This article describes BabyIAXO, an intermediate experimental stage of the International Axion Observatory (IAXO), proposed to be sited at DESY. IAXO is a large-scale axion helioscope that will look for axions and axion-like particles (ALPs), produced in Sun, with unprecedented sensitivity. BabyIAXO conceived test all subsystems (magnet, optics detectors) relevant scale final system thus serve as prototype IAXO, but same time fully-fledged physics reach itself, potential discovery....
A bstract We present results of the Relic Axion Dark-Matter Exploratory Setup (RADES), a detector which is part CERN Solar Telescope (CAST), searching for axion dark matter in 34.67 μ eV mass range. radio frequency cavity consisting 5 sub-cavities coupled by inductive irises took physics data inside CAST dipole magnet first time using this filter-like haloscope geometry. An exclusion limit with 95% credibility level on axion-photon coupling constant g aγ ≳ 4 × 10 − 13 GeV 1 over range 34 ....
The CAST-CAPP axion haloscope, operating at CERN inside the CAST dipole magnet, has searched for axions in 19.74 $\mu$eV to 22.47 mass range. detection concept follows Sikivie haloscope principle, where Dark Matter convert into photons within a resonator immersed magnetic field. is an array of four individual rectangular cavities inserted strong phase-matched maximize sensitivity. Here we report on data acquired 4124 h from 2019 2021. Each cavity equipped with fast frequency tuning mechanism...
The OPERA experiment is designed to search for ${\ensuremath{\nu}}_{\ensuremath{\mu}}\ensuremath{\rightarrow}{\ensuremath{\nu}}_{\ensuremath{\tau}}$ oscillations in appearance mode, i.e., through the direct observation of $\ensuremath{\tau}$ lepton ${\ensuremath{\nu}}_{\ensuremath{\tau}}$-charged current interactions. has taken data five years, since 2008, with CERN Neutrino Gran Sasso beam. Previously, two ${\ensuremath{\nu}}_{\ensuremath{\tau}}$ candidates a decaying into hadrons were...
In non-hadronic axion models, which have a tree-level axion-electron interaction, the Sun produces strong flux by bremsstrahlung, Compton scattering, and axio-recombination, ``BCA processes.'' Based on new calculation of this flux, including for first time we derive limits Yukawa coupling gae axion-photon interaction strength gaγ using CAST phase-I data (vacuum phase). For ma≲10 meV/c2 find < 8.1 × 10−23 GeV−1 at 95% CL. We stress that next-generation helioscope such as proposed IAXO could...
A new method of momentum measurement charged particles through multiple Coulomb scattering (MCS) in the OPERA lead-emulsion target is presented. It based on precise measurements track angular deviations carried out thanks to very high resolution nuclear emulsions. The algorithm has been tested with Monte Carlo pions. results are found describe within expected uncertainties data obtained from test beams. We also present a comparison muon momenta evaluated MCS those determined by electronic...
The OPERA neutrino detector at the underground Gran Sasso Laboratory (LNGS) was designed to perform first detection of oscillations in appearance mode, through study νμ → ντ oscillations. apparatus consists a lead/emulsion-film target complemented by electronic detectors. It is placed high-energy, long-baseline CERN LNGS beam (CNGS) 730 km away from source. In August 2006, run with CNGS neutrinos successfully conducted. A sample events collected, statistically consistent integrated...
A bstract first result of the search for ν μ → e oscillations in OPERA experiment, located at Gran Sasso Underground Laboratory, is presented. The experiment looked appearance CNGS neutrino beam using data collected 2008 and 2009. Data are compatible with non-oscillation hypothesis three-flavour mixing model. further analysis same constrains non-standard oscillation parameters θ new $ \varDelta m_{\mathrm{new}}^2 suggested by LSND MiniBooNE experiments. For large values ( > 0.1 eV 2 ),...
The CERN Axion Solar Telescope (CAST) searches for $a\ensuremath{\rightarrow}\ensuremath{\gamma}$ conversion in the 9 T magnetic field of a refurbished LHC test magnet that can be directed toward Sun. Two parallel bores filled with helium adjustable pressure to match x-ray refractive mass ${m}_{\ensuremath{\gamma}}$ axion search ${m}_{a}$. After vacuum phase (2003--2004), which is optimal ${m}_{a}\ensuremath{\lesssim}0.02\text{ }\text{ }\mathrm{eV}$, we used $^{4}\mathrm{He}$ 2005--2007...
The OPERA experiment is searching for nu_mu -> nu_tau oscillations in appearance mode i.e. via the direct detection of tau leptons charged current interactions. evidence has been previously reported with three candidate events using a sub-sample data from 2008-2012 runs. We report here fourth event, decaying into hadron, found after adding 2012 run without any muon final state to sample. Given number analysed and low background, are established significance 4.2sigma.
We have searched for 14.4 keV solar axions or more general axion-like particles (ALPs), that may be emitted in the M1 nuclear transition of 57Fe, by using axion-to-photon conversion CERN Axion Solar Telescope (CAST) with evacuated magnet bores (Phase I). From absence excess monoenergetic X-rays when was pointing to Sun, we set model-independent constraints on coupling constants pseudoscalar couple two photons and a nucleon gaγ|−1.19gaN0+gaN3| < 1.36 × 10−16 GeV−1 ma 0.03 eV at 95% confidence level.
The OPERA experiment is based on a hybrid technology combining electronic detectors and nuclear emulsions. collected muon-neutrino interactions during the 2008 2009 physics runs of CNGS neutrino beam, produced at CERN with an energy range about 5-35 GeV. A total $5.3 \times 10^{19}$ protons target equivalent luminosity has been analysed detectors: scintillator strips trackers magnetic muon spectrometers equipped resistive plate gas chambers drift tubes, allowing detailed reconstruction...