Search results for "Gamma"
showing 10 items of 3093 documents
Dense matter with eXTP
2019
In this White Paper we present the potential of the Enhanced X-ray Timing and Polarimetry (eXTP) mission for determining the nature of dense matter; neutron star cores host an extreme density regime which cannot be replicated in a terrestrial laboratory. The tightest statistical constraints on the dense matter equation of state will come from pulse profile modelling of accretion-powered pulsars, burst oscillation sources, and rotation-powered pulsars. Additional constraints will derive from spin measurements, burst spectra, and properties of the accretion flows in the vicinity of the neutron star. Under development by an international Consortium led by the Institute of High Energy Physics o…
Granulomatous mycosis fungoides, a rare subtype of cutaneous T-cell lymphoma
2015
Granulomatous mycosis fungoides (GMF) is an unusual histologic subtype of cutaneous T-cell lymphoma.1 The diagnosis of GMF is usually established after observation of a granulomatous inflammatory reaction associated with a malignant lymphoid infiltrate. Epidermotropism, a clue to diagnosis in classical mycosis fungoides (MF) may be absent in about 47% of cases of GMF.2 In some instances, the granulomatous component may be intense and obscures the lymphomatous component of the infiltrate.1 There are no distinctive clinical patterns associated with GMF.1, 3
Reduced reference 3D mesh quality assessment based on statistical models
2015
International audience; During their geometry processing and transmission 3D meshes are subject to various visual processing operations like compression, watermarking, remeshing, noise addition and so forth. In this context it is indispensable to evaluate the quality of the distorted mesh, we talk here about the mesh visual quality (MVQ) assessment. Several works have tried to evaluate the MVQ using simple geometric measures, However this metrics do not correlate well with the subjective score since they fail to reflect the perceived quality. In this paper we propose a new objective metric to evaluate the visual quality between a mesh with a perfect quality called reference mesh and its dis…
No-Reference 3D Mesh Quality Assessment Based on Dihedral Angles Model and Support Vector Regression
2016
International audience; 3D meshes are subject to various visual distortions during their transmission and geometrical processing. Several works have tried to evaluate the visual quality using either full reference or reduced reference approaches. However, these approaches require the presence of the reference mesh which is not available in such practical situations. In this paper, the main contribution lies in the design of a computational method to automatically predict the perceived mesh quality without reference and without knowing beforehand the distortion type. Following the no-reference (NR) quality assessment principle, the proposed method focuses only on the distorted mesh. Specific…
Parametriskie integrāļi: teorijas jautājumi un pielietojumi Beta un Gamma funkciju izpētē
2015
Maģistra darbā ir aplūkoti teorijas jautājumi par parametriskajiem integrāļiem un tajā skaitā arī par Gamma un Beta funkcijām. Doti uzdevumi ar atrisinājumiem par atbilstošām tēmām. Pirmā.nodaļā tiek definēts no parametra atkarīgais integrālis, apskatītas tā īpašības un atrisināšanas metodes. Otrā nodaļā ir apkopots teorijas izklāsts par Eilera integrāļiem. Dots ieskats par Gamma funkcijas vispārinājumu kompleksā plaknē.
Sensitivity of the Cherenkov Telescope Array for probing cosmology and fundamental physics with gamma-ray propagation
2021
Full list of authors: Abdalla, H.; Abe, H.; Acero, F.; Acharyya, A.; Adam, R.; Agudo, I; Aguirre-Santaella, A.; Alfaro, R.; Alfaro, J.; Alispach, C.; Aloisio, R.; Batista, R. Alves; Amati, L.; Amato, E.; Ambrosi, G.; Anguner, E. O.; Araudo, A.; Armstrong, T.; Arqueros, F.; Arrabito, L.; Asano, K.; Ascasibar, Y.; Ashley, M.; Backes, M.; Balazs, C.; Balbo, M.; Balmaverde, B.; Baquero Larriva, A.; Martins, V. Barbosa; Barkov, M.; Baroncelli, L.; de Almeida, U. Barres; Barrio, J. A.; Batista, P-, I; Becerra Gonzalez, J.; Becherini, Y.; Beck, G.; Tjus, J. Becker; Belmont, R.; Benbow, W.; Bernardini, E.; Berti, A.; Berton, M.; Bertucci, B.; Beshley, V; Bi, B.; Biasuzzi, B.; Biland, A.; Bissaldi, …
Scaler mode technique for the ARGO-YBJ detector
2008
The ARGO-YBJ experiment has been designed to study the Extensive Air Showers with an energy threshold lower than that of the existing arrays by exploiting the high altitude location(4300 m a.s.l. in Tibet, P.R. China) and the full ground plane coverage. The lower energy limit of the detector (E $\sim$ 1 GeV) is reached by the scaler mode technique, i.e. recording the counting rate at fixed time intervals. At these energies, transient signals due to local (e.g. Forbush Decreases) and cosmological (e.g. Gamma Ray Bursts) phenomena are expected as a significant variation of the counting rate compared to the background. In this paper the performance of the ARGO-YBJ detector operating in scaler …
Localisation of gamma-ray bursts from the combined SpIRIT+HERMES-TP/SP nano-satellite constellation
2023
Multi-messenger observations of the transient sky to detect cosmic explosions and counterparts of gravitational wave mergers critically rely on orbiting wide-FoV telescopes to cover the wide range of wavelengths where atmospheric absorption and emission limit the use of ground facilities. Thanks to continuing technological improvements, miniaturised space instruments operating as distributed-aperture constellations are offering new capabilities for the study of high energy transients to complement ageing existing satellites. In this paper we characterise the performance of the upcoming joint SpIRIT + HERMES-TP/SP nano-satellite constellation for the localisation of high-energy transients th…
Search for Neutrino‐induced Cascades from Gamma‐Ray Bursts with AMANDA
2007
Using the neutrino telescope AMANDA-II, we have conducted two analyses searching for neutrino-induced cascades from gamma-ray bursts. No evidence of astrophysical neutrinos was found, and limits are presented for several models. We also present neutrino effective areas which allow the calculation of limits for any neutrino production model. The first analysis looked for a statistical excess of events within a sliding window of 1 or 100 seconds (for short and long burst classes, respectively) during the years 2001-2003. The resulting upper limit on the diffuse flux normalization times E^2 for the Waxman-Bahcall model at 1 PeV is 1.6 x 10^-6 GeV cm^-2 s^-1 sr^-1 (a factor of 120 above the the…
Gamma-convergence of Gaussian fractional perimeter
2021
Abstract We prove the Γ-convergence of the renormalised Gaussian fractional s-perimeter to the Gaussian perimeter as s → 1 - {s\to 1^{-}} . Our definition of fractional perimeter comes from that of the fractional powers of Ornstein–Uhlenbeck operator given via Bochner subordination formula. As a typical feature of the Gaussian setting, the constant appearing in front of the Γ-limit does not depend on the dimension.