13 research outputs found
Searches for Point-like and extended neutrino sources close to the Galactic Centre using the ANTARES neutrino Telescope
A search for cosmic neutrino sources using six years of data collected by the ANTARES neutrino telescope has been performed. Clusters of muon neutrinos over the expected atmospheric background have been looked for. No clear signal has been found. The most signal-like accumulation of events is located at equatorial coordinates R.A. = -46 degrees.8 and decl. = -64 degrees.9 and corresponds to a 2.2 sigma background fluctuation. In addition, upper limits on the flux normalization of an E-2 muon neutrino energy spectrum have been set for 50 pre-selected astrophysical objects. Finally, motivated by an accumulation of seven events relatively close to the Galactic Center in the recently reported neutrino sample of the IceCube telescope, a search for point sources in a broad region around this accumulation has been carried out. No indication of a neutrino signal has been found in the ANTARES data and upper limits on the flux normalization of an E-2 energy spectrum of neutrinos from point sources in that region have been set. The 90% confidence level upper limits on the muon neutrino flux normalization vary between 3.5 and 5.1 x 10(-8) GeV cm(-2) s(-1), depending on the exact location of the source
Observation of the cosmic ray shadow of the Sun with the ANTARES neutrino telescope
[EN] The ANTARES detector is an undersea neutrino telescope in the Mediterranean Sea. The search for pointlike neutrino sources is one of the main goals of the ANTARES telescope, requiring a reliable method to evaluate the detector angular resolution and pointing accuracy. This work describes the study of the Sun ¿shadow¿ effect with the ANTARES detector. The shadow is the deficit in the atmospheric muon flux in the direction of the Sun caused by the absorption of the primary cosmic rays. This analysis is based on the data collected between 2008 and 2017 by the ANTARES telescope. The observed statistical significance of the Sun shadow detection is 3.7¿, with an estimated angular resolution of 0.59° +- 0.10°for downward-going muons. The pointing accuracy is found to be consistent with the expectations and no evidence of systematic pointing shifts is observed.The authors acknowledge the financial support of the funding agencies: Centre National de la Recherche Scientifique, Commissariat `a l'' energie atomique et aux energies alternatives, Commission Europeenne (FEDER fund and Marie Curie Program), Institut Universitaire de France, LabEx UnivEarthS (ANR-10-LABX-0023 and ANR-18-IDEX-0001), R ' egion Ile-de-France (DIM-ACAV), Region Alsace (contract CPER), Region Provence-Alpes-Cote d'Azur, Departement du Var and Ville de La Seyne-sur-Mer, France; Bundesministerium fur Bildung und Forschung, Germany; Istituto Nazionale di Fisica Nucleare, Italy; Nederlandse organisatie voor Wetenschappelijk Onderzoek, the Netherlands; Council of the President of the Russian Federation for Young Scientists and Leading Scientific Schools supporting grants, Russia; Executive Unit for Financing Higher Education, Research, Development and Innovation (UEFISCDI), Romania; Ministerio de Ciencia, Innovacion, Investigacion y Universidades (MCIU): Programa Estatal de Generacion de Conocimiento (refs. PGC2018-096663-B-C41, -A-C42, -B-C43, -B-C44) (MCIU/FEDER), Severo Ochoa Centre of Excellence and MultiDark Consolider (MCIU), Junta de Andalucia (refs. SOMM17/6104/UGR and A-FQM-053-UGR18), Generalitat Valenciana: Grisolia (ref. GRISOLIA/2018/119), Spain; Ministry of Higher Education, Scientific Research and Professional Training, Morocco. We also acknowledge the technical support of Ifremer, AIM and Foselev Marine for the sea operation and the CC-IN2P3 for the computing facilities.Albert, A.; Andre, M.; Anghinolfi, M.; Anton, G.; Ardid Ramírez, M.; Aubert, J.; Aublin, J.... (2020). Observation of the cosmic ray shadow of the Sun with the ANTARES neutrino telescope. Physical Review D: covering particles, fields, gravitation, and cosmology. 102(12):1-7. https://doi.org/10.1103/PhysRevD.102.122007S1710212Ageron, M., Aguilar, J. A., Al Samarai, I., Albert, A., Ameli, F., André, M., … Ardid, M. (2011). ANTARES: The first undersea neutrino telescope. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 656(1), 11-38. doi:10.1016/j.nima.2011.06.103Alexandreas, D. E., Allen, R. C., Berley, D., Biller, S. D., Burman, R. L., Cady, D. R., … Zhang, W. (1991). Observation of shadowing of ultrahigh-energy cosmic rays by the Moon and the Sun. Physical Review D, 43(5), 1735-1738. doi:10.1103/physrevd.43.1735Andreyev, Y. M., Zakidyshev, V. N., Karpov, S. N., & Khodov, V. N. (2002). Cosmic Research, 40(6), 559-564. doi:10.1023/a:1021553713199Borione, A., Catanese, M., Covault, C. E., Cronin, J. W., Fick, B. E., Gibbs, K. G., … van der Velde, J. C. (1994). Observation of the shadows of the Moon and Sun using 100 TeV cosmic rays. Physical Review D, 49(3), 1171-1177. doi:10.1103/physrevd.49.1171Cobb, J. H., Marshak, M. L., Allison, W. W. M., Alner, G. J., Ayres, D. S., Barrett, W. L., … Wall, D. (2000). Observation of a shadow of the Moon in the underground muon flux in the Soudan 2 detector. Physical Review D, 61(9). doi:10.1103/physrevd.61.092002Bartoli, B., Bernardini, P., Bi, X. J., Bleve, C., Bolognino, I., Branchini, P., … Cao, Z. (2012). Measurement of the cosmic ray antiproton/proton flux ratio at TeV energies with the ARGO-YBJ detector. Physical Review D, 85(2). doi:10.1103/physrevd.85.022002Abeysekara, A. U., Albert, A., Alfaro, R., Alvarez, C., Álvarez, J. D., Arceo, R., … Belmont-Moreno, E. (2018). Constraining the
p¯/p
ratio in TeV cosmic rays with observations of the Moon shadow by HAWC. Physical Review D, 97(10). doi:10.1103/physrevd.97.102005Adamson, P., Andreopoulos, C., Ayres, D. S., Backhouse, C., Barr, G., Barrett, W. L., … Bock, G. J. (2011). Observation in the MINOS far detector of the shadowing of cosmic rays by the sun and moon. Astroparticle Physics, 34(6), 457-466. doi:10.1016/j.astropartphys.2010.10.010Aartsen, M. G., Ackermann, M., Adams, J., Aguilar, J. A., Ahlers, M., Ahrens, M., … Ansseau, I. (2019). Detection of the Temporal Variation of the Sun’s Cosmic Ray Shadow with the IceCube Detector. The Astrophysical Journal, 872(2), 133. doi:10.3847/1538-4357/aaffd1Albert, A., André, M., Anghinolfi, M., Anton, G., Ardid, M., Aubert, J.-J., … Barrios-Martít, J. (2018). The cosmic ray shadow of the Moon observed with the ANTARES neutrino telescope. The European Physical Journal C, 78(12). doi:10.1140/epjc/s10052-018-6451-3First search for neutrinos in correlation with gamma-ray bursts with the ANTARES neutrino telescope. (2013). Journal of Cosmology and Astroparticle Physics, 2013(03), 006-006. doi:10.1088/1475-7516/2013/03/006Aguilar, J. A., Al Samarai, I., Albert, A., André, M., Anghinolfi, M., Anton, G., … Astraatmadja, T. (2011). A fast algorithm for muon track reconstruction and its application to the ANTARES neutrino telescope. Astroparticle Physics, 34(9), 652-662. doi:10.1016/j.astropartphys.2011.01.003BECHERINI, Y., MARGIOTTA, A., SIOLI, M., & SPURIO, M. (2006). A parameterisation of single and multiple muons in the deep water or ice. Astroparticle Physics, 25(1), 1-13. doi:10.1016/j.astropartphys.2005.10.005Carminati, G., Bazzotti, M., Margiotta, A., & Spurio, M. (2008). Atmospheric MUons from PArametric formulas: a fast GEnerator for neutrino telescopes (MUPAGE). Computer Physics Communications, 179(12), 915-923. doi:10.1016/j.cpc.2008.07.014Yepes-Ramírez, H. (2013). Characterization of optical properties of the site of the ANTARES neutrino telescope. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 725, 203-206. doi:10.1016/j.nima.2012.11.143Fusco, L. A., & Margiotta, A. (2016). The Run-by-Run Monte Carlo simulation for the ANTARES experiment. EPJ Web of Conferences, 116, 02002. doi:10.1051/epjconf/201611602002Albert, A., André, M., Anghinolfi, M., Anton, G., Ardid, M., Aubert, J.-J., … Basa, S. (2017). First all-flavor neutrino pointlike source search with the ANTARES neutrino telescope. Physical Review D, 96(8). doi:10.1103/physrevd.96.082001Albert, A., André, M., Anghinolfi, M., Anton, G., Ardid, M., Aubert, J.-J., … Belhorma, B. (2020). ANTARES and IceCube Combined Search for Neutrino Point-like and Extended Sources in the Southern Sky. The Astrophysical Journal, 892(2), 92. doi:10.3847/1538-4357/ab7afbAdrián-Martínez, S., Albert, A., André, M., Anghinolfi, M., Anton, G., Ardid, M., … Basa, S. (2014). SEARCHES FOR POINT-LIKE AND EXTENDED NEUTRINO SOURCES CLOSE TO THE GALACTIC CENTER USING THE ANTARES NEUTRINO TELESCOPE. The Astrophysical Journal, 786(1), L5. doi:10.1088/2041-8205/786/1/l
Towards More Realistic Biomechanical Modelling of Tumours under Mammographic Compressions
In this paper we present a biomechanical model of isolated breast tumours under mammographic compression forces. We apply a range of reported mechanical properties, both linear elastic and hyperelastic. We also introduce a volume of increased density/stiffness around the tumour. These variables have a non-negligible effect on stresses and strains, as shown in this work. © 2010 Springer-Verlag
Investigation of routing reliability of vehicular ad hoc networks
In intelligent transportation systems, the cooperation between vehicles and the road side units is essential to bring these systems to fruition. Vehicular ad hoc networks (VANETs) are a promising technology to enable the communications among vehicles on one hand and between vehicles and road side units on the other hand. However, it is a challenging task to develop a reliable routing algorithm for VANETs due to the high mobility and the frequent changes of the network topology. Communication links are highly vulnerable to disconnection in VANETs; hence, the routing reliability of these ever-changing networks needs to be paid special attention. In this paper, we propose a new vehicular reliability model to facilitate the reliable routing in VANETs. The link reliability is defined as the probability that a direct communication link between two vehicles will stay continuously available over a specified time period. Furthermore, the link reliability value is accurately calculated using the location, direction and velocity information of vehicles along the road. We extend the well-known ad hoc on-demand distance vector (AODV) routing protocol to propose our reliable routing protocol AODV-R. Simulation results demonstrate that AODV-R outperforms significantly the AODV routing protocol in terms of better delivery ratio and less link failures while maintaining a reasonable routing control overhead
北部ケルマディック島弧の熱水性魚類から同定された新規の恒常性維持システム ―極限環境適 応に注目した医生物学モデルの開拓にむけて.
http://www.godac.jamstec.go.jp/darwin/cruise/yokosuka/yk13-11/
Linear Stereo-co-oligopeptides with AlternatingD- andL-Residues. I. Synthesis and Mass Spectrometric Behavior of the Members of a Series with Valine Residues
Synthesis and characterization of poly(vinyl ferrocene) grafted hydroxyl-terminated poly(butadiene): A propellant binder with a built-in burn-rate catalyst
Copy number variation of individual cattle genomes using next-generation sequencing
Copy number variations (CNVs) affect a wide range of phenotypic traits; however, CNVs in or near segmental duplication regions are often intractable. Using a read depth approach based on next-generation sequencing, we examined genome-wide copy number differences among five taurine (three Angus, one Holstein, and one Hereford) and one indicine (Nelore) cattle. Within mapped chromosomal sequence, we identified 1265 CNV regions comprising similar to 55.6-Mbp sequence-476 of which (similar to 38%) have not previously been reported. We validated this sequence-based CNV call set with array comparative genomic hybridization (aCGH), quantitative PCR (qPCR), and fluorescent in situ hybridization (FISH), achieving a validation rate of 82% and a false positive rate of 8%. We further estimated absolute copy numbers for genomic segments and annotated genes in each individual. Surveys of the top 25 most variable genes revealed that the Nelore individual had the lowest copy numbers in 13 cases (similar to 52%, chi(2) test; P-value <0.05). In contrast, genes related to pathogen- and parasite-resistance, such as CATHL4 and ULBP17, were highly duplicated in the Nelore individual relative to the taurine cattle, while genes involved in lipid transport and metabolism, including APOL3 and FABP2, were highly duplicated in the beef breeds. These CNV regions also harbor genes like BPIFA2A (BSP30A) and WC1, suggesting that some CNVs may be associated with breed-specific differences in adaptation, health, and production traits. By providing the first individualized cattle CNV and segmental duplication maps and genome-wide gene copy number estimates, we enable future CNV studies into highly duplicated regions in the cattle genome