arXiv subjects

M. Chabab

Publications and source records attributed to M. Chabab.

At least 91 records · Page 5Linked to original sources

arXiv2019

Bohr Hamiltonian with Pöschl Teller potential in γ unstable and γ stable pictures

In this paper, we present an analytical solution for the Bohr Hamiltonian with the trigonometric Pöschl Teller (P.T) potential in the cases of γ unstable nuclei and γ stable axially symmetric prolate deformed ones with γ = 0. The energy spectra and corresponding wave functions are derived by means of the asymptotic iteration method. In addition, B(E2) transition rates are calculated and compared with experimental data. Overall good agreement is obtained for inter and intra band transitions within ground state and \b{eta} bands. Our numerical results, particularly for transition rates are much closer to experimental ones in comparison with those obtained by Davidson and Kratzer potentials which are widely used in the literature.

nucl-th↗

arXiv2019

A Search for Cosmic Neutrino and Gamma-Ray Emitting Transients in 7.3 Years of ANTARES and Fermi LAT Data

We analyze 7.3 years of ANTARES high-energy neutrino and Fermi LAT γ-ray data in search of cosmic neutrino + γ-ray (ν+γ) transient sources or source populations. Our analysis has the potential to detect either individual ν+γ transient sources (durations δt < 1000~s), if they exhibit sufficient γ-ray or neutrino multiplicity, or a statistical excess of ν+γ transients of lower multiplicities. Treating ANTARES track and cascade event types separately, we establish detection thresholds by Monte Carlo scrambling of the neutrino data, and determine our analysis sensitivity by signal injection against scrambled datasets. We find our analysis is sensitive to ν+γ transient populations responsible for $>$5\% of the observed gamma-coincident neutrinos in the track data at 90\% confidence. Applying our analysis to the unscrambled data reveals no individual ν+γ events of high significance; two ANTARES track + Fermi γ-ray events are identified that exceed a once per decade false alarm rate threshold ($p=17\%$). No evidence for subthreshold ν+γ source populations is found among the track ($p=39\%$) or cascade ($p=60\%$) events. While TXS 0506+056, a blazar and variable (non-transient) Fermi γ-ray source, has recently been identified as the first source of high-energy neutrinos, the challenges in reconciling observations of the Fermi γ-ray sky, the IceCube high-energy cosmic neutrinos, and ultra-high energy cosmic rays using only blazars suggest a significant contribution by other source populations. Searches for transient sources of high-energy neutrinos remain interesting, with the potential for neutrino clustering or multimessenger coincidence searches to lead to discovery of the first ν+γ transients.

astro-ph.HE↗

arXiv2019

The Control Unit of the KM3NeT Data Acquisition System

The KM3NeT Collaboration runs a multi-site neutrino observatory in the Mediterranean Sea. Water Cherenkov particle detectors, deep in the sea and far off the coasts of France and Italy, are already taking data while incremental construction progresses. Data Acquisition Control software is operating off-shore detectors as well as testing and qualification stations for their components. The software, named Control Unit, is highly modular. It can undergo upgrades and reconfiguration with the acquisition running. Interplay with the central database of the Collaboration is obtained in a way that allows for data taking even if Internet links fail. In order to simplify the management of computing resources in the long term, and to cope with possible hardware failures of one or more computers, the KM3NeT Control Unit software features a custom dynamic resource provisioning and failover technology, which is especially important for ensuring continuity in case of rare transient events in multi-messenger astronomy. The software architecture relies on ubiquitous tools and broadly adopted technologies and has been successfully tested on several operating systems.

astro-ph.IM↗

arXiv2019

Letter of Interest for a Neutrino Beam from Protvino to KM3NeT/ORCA

The Protvino accelerator facility located in the Moscow region, Russia, is in a good position to offer a rich experimental research program in the field of neutrino physics. Of particular interest is the possibility to direct a neutrino beam from Protvino towards the KM3NeT/ORCA detector, which is currently under construction in the Mediterranean Sea 40 km offshore Toulon, France. This proposal is known as P2O. Thanks to its baseline of 2595 km, this experiment would yield an unparalleled sensitivity to matter effects in the Earth, allowing for the determination of the neutrino mass ordering with a high level of certainty after only a few years of running at a modest beam intensity of $\approx$ 90 kW. With a prolonged exposure ($\approx$ 1500 kW*yr), a 2$σ$ sensitivity to the leptonic CP-violating Dirac phase can be achieved. A second stage of the experiment, comprising a further intensity upgrade of the accelerator complex and a densified version of the ORCA detector (Super-ORCA), would allow for up to a 6$σ$ sensitivity to CP violation and a 10$^\circ$-17$^\circ$ resolution on the CP phase after 10 years of running with a 450 kW beam, competitive with other planned experiments. The initial composition and energy spectrum of the neutrino beam would need to be monitored by a near detector, to be constructed several hundred meters downstream from the proton beam target. The same neutrino beam and near detector set-up would also allow for neutrino-nucleus cross section measurements to be performed. A short-baseline sterile neutrino search experiment would also be possible.

physics.ins-det↗

arXiv2019

KM3NeT front-end and readout electronics system: hardware, firmware and software

The KM3NeT research infrastructure being built at the bottom of the Mediterranean Sea will host water-Cherenkov telescopes for the detection of cosmic neutrinos. The neutrino telescopes will consist of large volume three-dimensional grids of optical modules to detect the Cherenkov light from charged particles produced by neutrino-induced interactions. Each optical module houses 31 3-inch photomultiplier tubes, instrumentation for calibration of the photomultiplier signal and positioning of the optical module and all associated electronics boards. By design, the total electrical power consumption of an optical module has been capped at seven watts. This paper presents an overview of the front-end and readout electronics system inside the optical module, which has been designed for a 1~ns synchronization between the clocks of all optical modules in the grid during a life time of at least 20 years.

astro-ph.IM↗

arXiv2019

Measuring the atmospheric neutrino oscillation parameters and constraining the 3+1 neutrino model with ten years of ANTARES data

The ANTARES neutrino telescope has an energy threshold of a few tens of GeV. This allows to study the phenomenon of atmospheric muon neutrino disappearance due to neutrino oscillations. In a similar way, constraints on the 3+1 neutrino model, which foresees the existence of one sterile neutrino, can be inferred. Using data collected by the ANTARES neutrino telescope from 2007 to 2016, a new measurement of $Δm^2_{32}$ and $θ_{23}$ has been performed - which is consistent with world best-fit values - and constraints on the 3+1 neutrino model have been derived.

hep-ex↗

arXiv2019

Comparaison between Coulomb and Hulthèn potentials within Bohr Hamiltonian for $γ$-rigid nuclei in the presence of minimal length

In this work we solve the Schrödinger equation for Bohr Hamiltonian with Coulomb and Hulthén potentials within the formalism of minimal length in order to obtain analytical expressions for the energy eigenvalues and eigenfunctions by means of asymptotic iteration method. The obtained formulas of the energy spectrum and wave functions, are used to calculate excitation energies and transition rates of $γ$-rigid nuclei and compared with the experimental data at the shape phase critical point X(3) in nuclei.

nucl-th↗

arXiv2019

Phase transitions and geothermodynamics of black holes in dRGT massive gravity

In this paper, we study the thermodynamics and geothermodynamics of spherical black hole solutions in dRGT massive gravity in a new extended phase space. Inspired by the work of Kastor et al. [1], by interpreting the graviton mass as a thermodynamical variable, we propose a first law of thermodynamics which include a mass term and establish a new Smarr Formula. Then, we perform a thermodynamical analysis to reveal the existence of a critical behavior for black holes in dRGT massive gravity with two different critical points through canonical and grand canonical ensembles. To consolidate these results, we make use of the thermodynamical geometry formalism, with the HPEM and the Gibbs free energy metrics, to derive the singularities of Ricci scalar curvatures and show that they coincide with those of the capacities. The effect of different values of the spacetime parameters on the stability conditions is also discussed.

hep-th↗

arXiv2019

Sensitivity of the KM3NeT/ARCA neutrino telescope to point-like neutrino sources

KM3NeT will be a network of deep-sea neutrino telescopes in the Mediterranean Sea. The KM3NeT/ARCA detector, to be installed at the Capo Passero site (Italy), is optimised for the detection of high-energy neutrinos of cosmic origin. Thanks to its geographical location on the Northern hemisphere, KM3NeT/ARCA can observe upgoing neutrinos from most of the Galactic Plane, including the Galactic Centre. Given its effective area and excellent pointing resolution, KM3NeT/ARCA will measure or significantly constrain the neutrino flux from potential astrophysical neutrino sources. At the same time, it will test flux predictions based on gamma-ray measurements and the assumption that the gamma-ray flux is of hadronic origin. Assuming this scenario, discovery potentials and sensitivities for a selected list of Galactic sources and to generic point sources with an $E^{-2}$ spectrum are presented. These spectra are assumed to be time independent. The results indicate that an observation with $3σ$ significance is possible in about six years of operation for the most intense sources, such as Supernovae Remnants RX\,J1713.7-3946 and Vela Jr. If no signal will be found during this time, the fraction of the gamma-ray flux coming from hadronic processes can be constrained to be below 50\% for these two objects.

astro-ph.HE↗

arXiv2019

$γ$-rigid triaxial nuclei in the presence of a minimal length via a quantum perturbation method

In this work, we derive a closed solution of the Shr$ \ddot{o} $dinger equation for Bohr Hamiltonien within the minimal length formalism. This formalism is inspired by Heisenberg algebra and a generlized uncertainty principle (GUP), applied to the geometrical collective Bohr- Mottelson model (BMM) of nuclei by means of deformed canonical commutation relation and the Pauli-Podolsky prescription. The problem is solved by means conjointly of asymptotic iteration method (AIM) and a quantum perturbation method (QPM) for transitional nuclei near the critical point symmetry Z(4) corresponding to phase transition from prolate to $γ$-rigid triaxial shape. A scaled Davidson potentiel is used as a restoring potential in order to get physical minimum. The agreement between the obtained theoretical results and the experimental data is very satisfactory.

nucl-th↗

arXiv2019

ANTARES neutrino search for time and space correlations with IceCube high-energy neutrino events

In the past years, the IceCube Collaboration has reported in several analyses the observation of astrophysical high-energy neutrino events. Despite a compelling evidence for the first identification of a neutrino source, TXS 0506+056, the origin of the majority of these events is still unknown. In this paper, a possible transient origin of the IceCube astrophysical events is searched for using neutrino events detected by the ANTARES telescope. The arrival time and direction of 6894 track-like and 160 shower-like events detected over 2346 days of livetime are examined to search for coincidences with 54 IceCube high-energy track-like neutrino events, by means of a maximum likelihood method. No significant correlation is observed and upper limits on the one-flavour neutrino fluence from the direction of the IceCube candidates are derived. The non-observation of time and space correlation within the time window of 0.1 days with the two most energetic IceCube events constrains the spectral index of a possible point-like transient neutrino source, to be harder than $-2.3$ and $-2.4$ for each event, respectively.

astro-ph.HE↗

arXiv2019

Probing correlation between photon orbits and phase structure of charged AdS black hole in massive gravity background

The phase structure of charged Anti-de Sitter black hole in massive gravity is investigated using the unstable circular photon orbits formalism, concretely we establish a direct link between the null geodesics and the critical behavior thermodynamic of such black hole solution. Our analysis reveals that the radius and the impact parameter corresponding to the unstable circular orbits can be used to probe the thermodynamic phase structure. We also show that the latter are key quantities to characterize the order of Van der Waals-like phase transition. Namely, we found a critical exponent around $ δ= 1/2 $. All these results support further that the photon trajectories can be used as a useful and crucial tool to probe the thermodynamic black holes criticality.

hep-th↗

arXiv2018

Search for Multi-messenger Sources of Gravitational Waves and High-energy Neutrinos with Advanced LIGO during its first Observing Run, ANTARES and IceCube

Astrophysical sources of gravitational waves, such as binary neutron star and black hole mergers or core-collapse supernovae, can drive relativistic outflows, giving rise to non-thermal high-energy emission. High-energy neutrinos are signatures of such outflows. The detection of gravitational waves and high-energy neutrinos from common sources could help establish the connection between the dynamics of the progenitor and the properties of the outflow. We searched for associated emission of gravitational waves and high-energy neutrinos from astrophysical transients with minimal assumptions using data from Advanced LIGO from its first observing run O1, and data from the ANTARES and IceCube neutrino observatories from the same time period. We focused on candidate events whose astrophysical origin could not be determined from a single messenger. We found no significant coincident candidate, which we used to constrain the rate density of astrophysical sources dependent on their gravitational wave and neutrino emission processes.

astro-ph.HE↗

arXiv2018

Joint constraints on Galactic diffuse neutrino emission from ANTARES and IceCube

The existence of diffuse Galactic neutrino production is expected from cosmic ray interactions with Galactic gas and radiation fields. Thus, neutrinos are a unique messenger offering the opportunity to test the products of Galactic cosmic ray interactions up to energies of hundreds of TeV. Here we present a search for this production using ten years of ANTARES track and shower data, as well as seven years of IceCube track data. The data are combined into a joint likelihood test for neutrino emission according to the KRA$_γ$ model assuming a 5 PeV per nucleon Galactic cosmic ray cutoff. No significant excess is found. As a consequence, the limits presented in this work start constraining the model parameter space for Galactic cosmic ray production and transport.

astro-ph.HE↗

arXiv2018

Probing the Higgs sector of $Y=0$ Higgs Triplet Model at LHC

In this paper, we investigate the Higgs Triplet Model with hypercharge $Y_Δ=0$ (HTM0), an extension of the Standard model, caracterised by a more involved scalar spectrum consisting of two CP even Higgs $h^0, H^0$ and two charged Higgs bosons $H^\pm$. We first show that the parameter space of HTM0, usually delimited by combined constraints originating from unitarity and BFB as well as experimental limits from LEP and LHC, is severely reduced when the modified Veltman conditions at one loop are also imposed. Then, we perform an rigorous analysis of Higgs decays either when $h^0$ is the SM-like or when the heaviest neutral Higgs $H^0$ is identified to the observed $125$ GeV Higgs boson at LHC. In these scenarios, we perform an extensive parameter scan, in the lower part of the scalar mass spectrum, with a particular focus on the Higgs to Higgs decay modes $H^0 \to h^0h^0, H^\pm\,H^\mp$ leading predominantly to invisible Higgs decays. Finally, we also study the scenario where $h^0, H^0$ are mass degenerate. We thus find that consistency with LHC signal strengths favours a light charged Higgs with a mass about $176\sim178$ GeV. Our analysis shows that the diphoton Higgs decay mode and $H \to Z γ$ are not always positively correlated as claimed in a previous study. Anti-correlation is rather seen in the scenario where $h$ is SM like, while correlation is sensitive to the sign of the potential parameter $λ$ when $H$ is identified to $125$ GeV Higgs.

hep-ph↗

arXiv2018

Search for high-energy neutrinos in coincidence with Fast Radio Bursts with the ANTARES neutrino telescope

In the past decade, a new class of bright transient radio sources with millisecond duration has been discovered. The origin of these so-called Fast Radio Bursts (FRBs) is still a great mystery despite the growing observational efforts made by various multi-wavelength and multi-messenger facilities. So far, many models have been proposed to explain FRBs but neither the progenitors nor the radiative and the particle acceleration processes at work have been clearly identified. In this paper, the question whether some hadronic processes may occur in the vicinity of the FRB source is assessed. If so, FRBs may contribute to the high energy cosmic-ray and neutrino fluxes. A search for these hadronic signatures has been done using the ANTARES neutrino telescope. The analysis consists in looking for high-energy neutrinos, in the TeV-PeV regime, spatially and temporally coincident with the detected FRBs. Most of the FRBs discovered in the period 2013-2017 were in the field of view of the ANTARES detector, which is sensitive mostly to events originating from the Southern hemisphere. From this period, 12 FRBs have been selected and no coincident neutrino candidate was observed. Upper limits on the per burst neutrino fluence have been derived using a power law spectrum, $\rm{\frac{dN}{dE_ν}\propto E_ν^{-γ}}$, for the incoming neutrino flux, assuming spectral indexes $γ$ = 1.0, 2.0, 2.5. Finally, the neutrino energy has been constrained by computing the total energy radiated in neutrinos assuming different distances for the FRBs. Constraints on the neutrino fluence and on the energy released are derived from the associated null results.

astro-ph.HE↗

arXiv2018

Long-term monitoring of the ANTARES optical module efficiencies using $^{40}\mathrm{K}$ decays in sea water

Cherenkov light induced by radioactive decay products is one of the major sources of background light for deep-sea neutrino telescopes such as ANTARES. These decays are at the same time a powerful calibration source. Using data collected by the ANTARES neutrino telescope from mid 2008 to 2017, the time evolution of the photon detection efficiency of optical modules is studied. A modest loss of only 20% in 9 years is observed. The relative time calibration between adjacent modules is derived as well.

astro-ph.IM↗

arXiv2018

Nuclear shape phase transitions within a correlation between two quantum concepts

We present a correlation that we have revealed, for the first time, between both quantum concepts, namely: the Minimal Length (ML) and the Deformation Dependent Mass (DDM) in transitional nuclei near the critical points symmetries (CPS) X(3) and Z(4). Such a correlation could be considered as a new signature for these CPS. This new signature allowed us to predict new candidate nuclei for these critical points.

nucl-th↗