45 research outputs found

    Search for muon-neutrino emission from GeV and TeV gamma-ray flaring blazars using five years of data of the ANTARES telescope

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    The ANTARES telescope is well-suited for detecting astrophysical transient neutrino sources as it can observe a full hemisphere of the sky at all times with a high duty cycle. The background due to atmospheric particles can be drastically reduced, and the point-source sensitivity improved, by selecting a narrow time window around possible neutrino production periods. Blazars, being radio-loud active galactic nuclei with their jets pointing almost directly towards the observer, are particularly attractive potential neutrino point sources, since they are among the most likely sources of the very high-energy cosmic rays. Neutrinos and gamma rays may be produced in hadronic interactions with the surrounding medium. Moreover, blazars generally show high time variability in their light curves at different wavelengths and on various time scales. This paper presents a time-dependent analysis applied to a selection of flaring gamma-ray blazars observed by the FERMI/LAT experiment and by TeV Cherenkov telescopes using five years of ANTARES data taken from 2008 to 2012. The results are compatible with fluctuations of the background. Upper limits on the neutrino fluence have been produced and compared to the measured gamma-ray spectral energy distribution.Comment: 27 pages, 16 figure

    GRIPS - Gamma-Ray Imaging, Polarimetry and Spectroscopy

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    We propose to perform a continuously scanning all-sky survey from 200 keV to 80 MeV achieving a sensitivity which is better by a factor of 40 or more compared to the previous missions in this energy range. The Gamma-Ray Imaging, Polarimetry and Spectroscopy (GRIPS) mission addresses fundamental questions in ESA's Cosmic Vision plan. Among the major themes of the strategic plan, GRIPS has its focus on the evolving, violent Universe, exploring a unique energy window. We propose to investigate γ\gamma-ray bursts and blazars, the mechanisms behind supernova explosions, nucleosynthesis and spallation, the enigmatic origin of positrons in our Galaxy, and the nature of radiation processes and particle acceleration in extreme cosmic sources including pulsars and magnetars. The natural energy scale for these non-thermal processes is of the order of MeV. Although they can be partially and indirectly studied using other methods, only the proposed GRIPS measurements will provide direct access to their primary photons. GRIPS will be a driver for the study of transient sources in the era of neutrino and gravitational wave observatories such as IceCUBE and LISA, establishing a new type of diagnostics in relativistic and nuclear astrophysics. This will support extrapolations to investigate star formation, galaxy evolution, and black hole formation at high redshifts.Comment: to appear in Exp. Astron., special vol. on M3-Call of ESA's Cosmic Vision 2010; 25 p., 25 figs; see also www.grips-mission.e

    Search for muon-neutrino emission from GeV and TeV gamma-ray flaring blazars using five years of data of the ANTARES telescope

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    The ANTARES telescope is well-suited for detecting astrophysical transient neutrino sources as it can observe a full hemisphere of the sky at all times with a high duty cycle. The background due to atmospheric particles can be drastically reduced, and the point-source sensitivity improved, by selecting a narrow time window around possible neutrino production periods. Blazars, being radio-loud active galactic nuclei with their jets pointing almost directly towards the observer, are particularly attractive potential neutrino point sources, since they are among the most likely sources of the very high-energy cosmic rays. Neutrinos and gamma rays may be produced in hadronic interactions with the surrounding medium. Moreover, blazars generally show high time variability in their light curves at different wavelengths and on various time scales. This paper presents a time-dependent analysis applied to a selection of flaring gamma-ray blazars observed by the FERMI/LAT experiment and by TeV Cherenkov telescopes using five years of ANTARES data taken from 2008 to 2012. The results are compatible with fluctuations of the background. Upper limits on the neutrino fluence have been produced and compared to the measured gamma-ray spectral energy distributionThe authors acknowledge the financial support of the funding agencies: Centre National de la Recherche Scientifique (CNRS), Commissariat a l'energie atomique et aux energies alternatives (CEA), Commission Europeenne (FEDER fund and Marie Curie Program), Region Ile-de-France (DIM-ACAV) Region Alsace (contrat CPER), Region Provence-Alpes-Cote d'Azur, Departement du Var and Ville de La Seyne-sur-Mer, France; Bundesministerium fur Bildung und Forschung (BMBF), Germany; Istituto Nazionale di Fisica Nucleare (INFN), Italy; Stichting voor Fundamenteel Onderzoek der Materie (FOM), Nederlandse organisatie voor Wetenschappelijk Onderzoek (NWO), the Netherlands; Council of the President of the Russian Federation for young scientists and leading scientific schools supporting grants, Russia; National Authority for Scientific Research (ANCS), Romania; Ministerio de Economia y Competitividad (MINECO), Prometeo and Grisolia programs of Generalitat Valenciana and MultiDark, Spain; Agence de l'Oriental and CNRST, 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.Adrián Martínez, S.; Albert, A.; André, M.; Anton, G.; Ardid Ramírez, M.; Aubert, J.; Baret, B.... (2015). Search for muon-neutrino emission from GeV and TeV gamma-ray flaring blazars using five years of data of the ANTARES telescope. Journal of Cosmology and Astroparticle Physics. 12(14):1-26. https://doi.org/10.1088/1475-7516/2015/12/014S1261214Becker, J. K. (2008). High-energy neutrinos in the context of multimessenger astrophysics. Physics Reports, 458(4-5), 173-246. doi:10.1016/j.physrep.2007.10.006Bloom, S. D., & Marscher, A. P. (1996). An Analysis of the Synchrotron Self-Compton Model for the Multi--Wave Band Spectra of Blazars. The Astrophysical Journal, 461, 657. doi:10.1086/177092Maraschi, L., Ghisellini, G., & Celotti, A. (1992). A jet model for the gamma-ray emitting blazar 3C 279. The Astrophysical Journal, 397, L5. doi:10.1086/186531Dermer, C. D., & Schlickeiser, R. (1993). Model for the High-Energy Emission from Blazars. The Astrophysical Journal, 416, 458. doi:10.1086/173251Sikora, M., Begelman, M. C., & Rees, M. J. (1994). Comptonization of diffuse ambient radiation by a relativistic jet: The source of gamma rays from blazars? The Astrophysical Journal, 421, 153. doi:10.1086/173633Gaisser, T. K., Halzen, F., & Stanev, T. (1995). Particle astrophysics with high energy neutrinos. Physics Reports, 258(3), 173-236. doi:10.1016/0370-1573(95)00003-yLearned, J. G., & Mannheim, K. (2000). High-Energy Neutrino Astrophysics. Annual Review of Nuclear and Particle Science, 50(1), 679-749. doi:10.1146/annurev.nucl.50.1.679Urry, C. M., & Padovani, P. (1995). Unified Schemes for Radio-Loud Active Galactic Nuclei. Publications of the Astronomical Society of the Pacific, 107, 803. doi:10.1086/133630Halzen, F., & Hooper, D. (2002). High-energy neutrino astronomy: the cosmic ray connection. Reports on Progress in Physics, 65(7), 1025-1078. doi:10.1088/0034-4885/65/7/201Böttcher, M. (2007). Modeling the emission processes in blazars. Astrophysics and Space Science, 309(1-4), 95-104. doi:10.1007/s10509-007-9404-0Böttcher, M., Reimer, A., Sweeney, K., & Prakash, A. (2013). LEPTONIC AND HADRONIC MODELING OFFERMI-DETECTED BLAZARS. The Astrophysical Journal, 768(1), 54. doi:10.1088/0004-637x/768/1/54Reynoso, M. M., Romero, G. E., & Medina, M. C. (2012). A two-component model for the high-energy variability of blazars. Astronomy & Astrophysics, 545, A125. doi:10.1051/0004-6361/201219873Atoyan, A. ., & Dermer, C. . (2004). Neutrinos and γ-rays of hadronic origin from AGN jets. New Astronomy Reviews, 48(5-6), 381-386. doi:10.1016/j.newar.2003.12.046Neronov, A., & Ribordy, M. (2009). IceCube sensitivity for neutrino flux from Fermi blazars in quiescent states. Physical Review D, 80(8). doi:10.1103/physrevd.80.083008Mücke, A., & Protheroe, R. J. (2001). A proton synchrotron blazar model for flaring in Markarian 501. Astroparticle Physics, 15(1), 121-136. doi:10.1016/s0927-6505(00)00141-9Abdo, A. A., Ackermann, M., Ajello, M., Allafort, A., Antolini, E., Atwood, W. B., … Barbiellini, G. (2010). THE FIRST CATALOG OF ACTIVE GALACTIC NUCLEI DETECTED BY THEFERMILARGE AREA TELESCOPE. The Astrophysical Journal, 715(1), 429-457. doi:10.1088/0004-637x/715/1/429Ageron, 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.2011.06.103Aguilar, J. A., Samarai, I. A., Albert, A., André, M., Anghinolfi, M., Anton, G., … Astraatmadja, T. (2011). Search for a diffuse flux of high-energy νμ with the ANTARES neutrino telescope. Physics Letters B, 696(1-2), 16-22. doi:10.1016/j.physletb.2010.11.070Adrián-Martínez, S., Al Samarai, I., Albert, A., André, M., Anghinolfi, M., Anton, G., … Aubert, J.-J. (2012). SEARCH FOR COSMIC NEUTRINO POINT SOURCES WITH FOUR YEARS OF DATA FROM THE ANTARES TELESCOPE. The Astrophysical Journal, 760(1), 53. doi:10.1088/0004-637x/760/1/53Adrián-Martínez, S., Albert, A., André, M., Anghinolfi, M., Anton, G., Ardid, M., … Barrios, J. (2014). A search for time dependent neutrino emission from microquasars with the ANTARES telescope. Journal of High Energy Astrophysics, 3-4, 9-17. doi:10.1016/j.jheap.2014.06.002Adrián-Martínez, S., Albert, A., Al Samarai, I., André, M., Anghinolfi, M., Anton, G., … Aubert, J.-J. (2013). Search for muon neutrinos from gamma-ray bursts with the ANTARES neutrino telescope using 2008 to 2011 data. Astronomy & Astrophysics, 559, A9. doi:10.1051/0004-6361/201322169Abdo, A. A., Ackermann, M., Ajello, M., Antolini, E., Baldini, L., Ballet, J., … Bellazzini, R. (2010). GAMMA-RAY LIGHT CURVES AND VARIABILITY OF BRIGHTFERMI-DETECTED BLAZARS. The Astrophysical Journal, 722(1), 520-542. doi:10.1088/0004-637x/722/1/520Ackermann, M., Ajello, M., Allafort, A., Antolini, E., Atwood, W. B., Axelsson, M., … Bastieri, D. (2011). THE SECOND CATALOG OF ACTIVE GALACTIC NUCLEI DETECTED BY THEFERMILARGE AREA TELESCOPE. The Astrophysical Journal, 743(2), 171. doi:10.1088/0004-637x/743/2/171Hovatta, T., Pavlidou, V., King, O. G., Mahabal, A., Sesar, B., Dancikova, R., … Surace, J. (2014). Connection between optical and γ-ray variability in blazars. Monthly Notices of the Royal Astronomical Society, 439(1), 690-702. doi:10.1093/mnras/stt2494Adrián-Martínez, S., Al Samarai, I., Albert, A., André, M., Anghinolfi, M., Anton, G., … Aubert, J.-J. (2012). Search for neutrino emission from gamma-ray flaring blazars with the ANTARES telescope. Astroparticle Physics, 36(1), 204-210. doi:10.1016/j.astropartphys.2012.06.001Aguilar, J. A., Albert, A., Ameli, F., Amram, P., Anghinolfi, M., Anton, G., … Aubert, J.-J. (2005). Study of large hemispherical photomultiplier tubes for the ANTARES neutrino telescope. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 555(1-2), 132-141. doi:10.1016/j.nima.2005.09.035Amram, P., Anghinolfi, M., Anvar, S., Ardellier-Desages, F. ., Aslanides, E., Aubert, J.-J., … Battaglieri, M. (2002). The ANTARES optical module. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 484(1-3), 369-383. doi:10.1016/s0168-9002(01)02026-5Adrián-Martínez, S., Ageron, M., Aguilar, J. A., Samarai, I. A., Albert, A., André, M., … Ardid, M. (2012). The positioning system of the ANTARES Neutrino Telescope. Journal of Instrumentation, 7(08), T08002-T08002. doi:10.1088/1748-0221/7/08/t08002Aguilar, J. A., Albert, A., Ameli, F., Anghinolfi, M., Anton, G., Anvar, S., … Basa, S. (2007). The data acquisition system for the ANTARES neutrino telescope. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 570(1), 107-116. doi:10.1016/j.nima.2006.09.098Agrawal, V., Gaisser, T. K., Lipari, P., & Stanev, T. (1996). Atmospheric neutrino flux above 1 GeV. Physical Review D, 53(3), 1314-1323. doi:10.1103/physrevd.53.1314BECHERINI, 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.2008.07.014Margiotta, A. (2013). Common simulation tools for large volume neutrino detectors. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 725, 98-101. doi:10.1016/j.nima.2012.11.172Adrián-Martínez, S., Albert, A., Al Samarai, I., André, M., Anghinolfi, M., Anton, G., … Aubert, J.-J. (2013). Measurement of the atmospheric ν μ energy spectrum from 100 GeV to 200 TeV with the ANTARES telescope. The European Physical Journal C, 73(10). doi:10.1140/epjc/s10052-013-2606-4Abdo, A. A., Ajello, M., Allafort, A., Baldini, L., Ballet, J., Barbiellini, G., … Bellazzini, R. (2013). THE SECONDFERMILARGE AREA TELESCOPE CATALOG OF GAMMA-RAY PULSARS. The Astrophysical Journal Supplement Series, 208(2), 17. doi:10.1088/0067-0049/208/2/17Scargle, J. D. (1981). Studies in astronomical time series analysis. I - Modeling random processes in the time domain. The Astrophysical Journal Supplement Series, 45, 1. doi:10.1086/190706Scargle, J. D. (1998). Studies in Astronomical Time Series Analysis. V. Bayesian Blocks, a New Method to Analyze Structure in Photon Counting Data. The Astrophysical Journal, 504(1), 405-418. doi:10.1086/306064Scargle, J. D., Norris, J. P., Jackson, B., & Chiang, J. (2013). STUDIES IN ASTRONOMICAL TIME SERIES ANALYSIS. VI. BAYESIAN BLOCK REPRESENTATIONS. The Astrophysical Journal, 764(2), 167. doi:10.1088/0004-637x/764/2/167Neyman, J. (1937). Outline of a Theory of Statistical Estimation Based on the Classical Theory of Probability. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 236(767), 333-380. doi:10.1098/rsta.1937.0005Aartsen, M. G., Ackermann, M., Adams, J., Aguilar, J. A., Ahlers, M., Ahrens, M., … Arguelles, C. (2015). SEARCHES FOR TIME-DEPENDENT NEUTRINO SOURCES WITH ICECUBE DATA FROM 2008 TO 2012. The Astrophysical Journal, 807(1), 46. doi:10.1088/0004-637x/807/1/46Kelner, S. R., Aharonian, F. A., & Bugayov, V. V. (2006). Energy spectra of gamma rays, electrons, and neutrinos produced at proton-proton interactions in the very high energy regime. Physical Review D, 74(3). doi:10.1103/physrevd.74.034018Kelner, S. R., & Aharonian, F. A. (2010). Erratum: Energy spectra of gamma rays, electrons, and neutrinos produced at interactions of relativistic protons with low energy radiation [Phys. Rev. D78, 034013 (2008)]. Physical Review D, 82(9). doi:10.1103/physrevd.82.099901Tchernin, C., Aguilar, J. A., Neronov, A., & Montaruli, T. (2013). Neutrino signal from extended Galactic sources in IceCube. Astronomy & Astrophysics, 560, A67. doi:10.1051/0004-6361/201321801Padovani, P., & Resconi, E. (2014). Are both BL Lacs and pulsar wind nebulae the astrophysical counterparts of IceCube neutrino events? Monthly Notices of the Royal Astronomical Society, 443(1), 474-484. doi:10.1093/mnras/stu1166Aleksić, J., Antonelli, L. A., Antoranz, P., Backes, M., Barrio, J. A., Bastieri, D., … Berger, K. (2011). MAGIC Observations and multiwavelength properties of the quasar 3C 279 in 2007 and 2009. Astronomy & Astrophysics, 530, A4. doi:10.1051/0004-6361/201116497Aleksić, J., Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Bangale, P., … Bednarek, W. (2014). MAGIC observations and multifrequency properties of the flat spectrum radio quasar 3C 279 in 2011. Astronomy & Astrophysics, 567, A41. doi:10.1051/0004-6361/201323036Murase, K., Inoue, Y., & Dermer, C. D. (2014). Diffuse neutrino intensity from the inner jets of active galactic nuclei: Impacts of external photon fields and the blazar sequence. Physical Review D, 90(2). doi:10.1103/physrevd.90.023007Finke, J. D., & Becker, P. A. (2014). FOURIER ANALYSIS OF BLAZAR VARIABILITY. The Astrophysical Journal, 791(1), 21. doi:10.1088/0004-637x/791/1/21Tavecchio, F., Ghisellini, G., & Guetta, D. (2014). STRUCTURED JETS IN BL LAC OBJECTS: EFFICIENT PeV NEUTRINO FACTORIES? The Astrophysical Journal, 793(1), L18. doi:10.1088/2041-8205/793/1/l1

    The Large Observatory For X-ray Timing: LOFT

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    LOFT, the Large Observatory for X-ray Timing, is a new space mission concept devoted to observations of Galactic and extra-Galactic sources in the X-ray domain with the main goals of probing gravity theory in the very strong field environment of black holes and other compact objects, and investigating the state of matter at supra-nuclear densities in neutron stars. The instruments on-board LOFT, the Large area detector and the Wide Field Monitor combine for the first time an unprecedented large effective area (~10 m2 at 8 keV) sensitive to X-ray photons mainly in the 2-30 keV energy range and a spectral resolution approaching that of CCD-based telescopes (down to 200 eV at 6 keV). LOFT is currently competing for a launch of opportunity in 2022 together with the other M3 mission candidates of the ESA Cosmic Vision Progra

    Joint Constraints on Galactic Diffuse Neutrino Emission from the ANTARES and IceCube Neutrino Telescopes

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    [EN] The existence of diffuse Galactic neutrino production is expected from cosmic-ray interactions with Galactic gas and radiation ¿elds. 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 Astronomy with a Neutrino Telescope and Abyss environmental RESearch (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 KRAg model assuming a 5 PeV per nucleon Galactic cosmic-ray cutoff. No signi¿cant excess is found. As a consequence, the limits presented in this Letter start constraining the model parameter space for Galactic cosmic-ray production and transport.Albert, A.; Andre, M.; Anghinolfi, M.; Ardid Ramírez, M.; Aubert, J-.; Aublin, J.; Avgitas, T.... (2018). Joint Constraints on Galactic Diffuse Neutrino Emission from the ANTARES and IceCube Neutrino Telescopes. The Astrophysical Journal. 868(2):1-7. https://doi.org/10.3847/2041-8213/aaeecfS178682Aartsen, M. G., Ackermann, M., Adams, J., Aguilar, J. A., Ahlers, M., Ahrens, M., … Anderson, T. (2017). Search for Astrophysical Sources of Neutrinos Using Cascade Events in IceCube. The Astrophysical Journal, 846(2), 136. doi:10.3847/1538-4357/aa8508Aartsen, M. G., Abraham, K., Ackermann, M., Adams, J., Aguilar, J. A., Ahlers, M., … Archinger, M. (2015). A COMBINED MAXIMUM-LIKELIHOOD ANALYSIS OF THE HIGH-ENERGY ASTROPHYSICAL NEUTRINO FLUX MEASURED WITH ICECUBE. The Astrophysical Journal, 809(1), 98. doi:10.1088/0004-637x/809/1/98Aartsen, M. G., Abraham, K., Ackermann, M., Adams, J., Aguilar, J. A., Ahlers, M., … Anderson, T. (2017). All-sky Search for Time-integrated Neutrino Emission from Astrophysical Sources with 7 yr of IceCube Data. The Astrophysical Journal, 835(2), 151. doi:10.3847/1538-4357/835/2/151Aartsen, M. G., Ackermann, M., Adams, J., Aguilar, J. A., Ahlers, M., Ahrens, M., … Anderson, T. (2017). Constraints on Galactic Neutrino Emission with Seven Years of IceCube Data. The Astrophysical Journal, 849(1), 67. doi:10.3847/1538-4357/aa8dfbAartsen, M. G., Ackermann, M., Adams, J., Aguilar, J. A., Ahlers, M., Ahrens, M., … Ansseau, I. (2017). The IceCube Neutrino Observatory: instrumentation and online systems. Journal of Instrumentation, 12(03), P03012-P03012. doi:10.1088/1748-0221/12/03/p03012Ackermann, M., Ajello, M., Atwood, W. B., Baldini, L., Ballet, J., Barbiellini, G., … Berenji, B. (2012). FERMI-LAT OBSERVATIONS OF THE DIFFUSE γ-RAY EMISSION: IMPLICATIONS FOR COSMIC RAYS AND THE INTERSTELLAR MEDIUM. The Astrophysical Journal, 750(1), 3. doi:10.1088/0004-637x/750/1/3Adrián-Martínez, S., Ageron, M., Aguilar, J. A., Samarai, I. A., Albert, A., André, M., … Ardid, M. (2012). The positioning system of the ANTARES Neutrino Telescope. Journal of Instrumentation, 7(08), T08002-T08002. doi:10.1088/1748-0221/7/08/t08002Ageron, 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.2011.06.103Ahn, H. S., Allison, P., Bagliesi, M. G., Beatty, J. J., Bigongiari, G., Childers, J. T., … Zinn, S. Y. (2010). DISCREPANT HARDENING OBSERVED IN COSMIC-RAY ELEMENTAL SPECTRA. The Astrophysical Journal, 714(1), L89-L93. doi:10.1088/2041-8205/714/1/l89Albert, A., André, M., Anghinolfi, M., Anton, G., Ardid, M., Aubert, J.-J., … Basa, S. (2017). New constraints on all flavor Galactic diffuse neutrino emission with the ANTARES telescope. Physical Review D, 96(6). doi:10.1103/physrevd.96.062001Antoni, T., Apel, W. D., Badea, A. F., Bekk, K., Bercuci, A., Blümer, J., … Zabierowski, J. (2005). KASCADE measurements of energy spectra for elemental groups of cosmic rays: Results and open problems. Astroparticle Physics, 24(1-2), 1-25. doi:10.1016/j.astropartphys.2005.04.001Apel, W. D., Arteaga-Velázquez, J. C., Bekk, K., Bertaina, M., Blümer, J., Bozdog, H., … Cossavella, F. (2013). KASCADE-Grande measurements of energy spectra for elemental groups of cosmic rays. Astroparticle Physics, 47, 54-66. doi:10.1016/j.astropartphys.2013.06.004Gaggero, D., Grasso, D., Marinelli, A., Taoso, M., & Urbano, A. (2017). Diffuse Cosmic Rays Shining in the Galactic Center: A Novel Interpretation of H.E.S.S. and Fermi-LAT γ -Ray Data. Physical Review Letters, 119(3). doi:10.1103/physrevlett.119.031101Gaggero, D., Grasso, D., Marinelli, A., Urbano, A., & Valli, M. (2015). THE GAMMA-RAY AND NEUTRINO SKY: A CONSISTENT PICTURE OF FERMI -LAT, MILAGRO, AND ICECUBE RESULTS. The Astrophysical Journal, 815(2), L25. doi:10.1088/2041-8205/815/2/l25Gaggero, D., Urbano, A., Valli, M., & Ullio, P. (2015). Gamma-ray sky points to radial gradients in cosmic-ray transport. Physical Review D, 91(8). doi:10.1103/physrevd.91.083012Vladimirov, A. E., Digel, S. W., Jóhannesson, G., Michelson, P. F., Moskalenko, I. V., Nolan, P. L., … Strong, A. W. (2011). GALPROP WebRun: An internet-based service for calculating galactic cosmic ray propagation and associated photon emissions. Computer Physics Communications, 182(5), 1156-1161. doi:10.1016/j.cpc.2011.01.01

    Consensus statement on abusive head trauma in infants and young children

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    Abusive head trauma (AHT) is the leading cause of fatal head injuries in children younger than 2 years. A multidisciplinary team bases this diagnosis on history, physical examination, imaging and laboratory findings. Because the etiology of the injury is multifactorial (shaking, shaking and impact, impact, etc.) the current best and inclusive term is AHT. There is no controversy concerning the medical validity of the existence of AHT, with multiple components including subdural hematoma, intracranial and spinal changes, complex retinal hemorrhages, and rib and other fractures that are inconsistent with the provided mechanism of trauma. The workup must exclude medical diseases that can mimic AHT. However, the courtroom has become a forum for speculative theories that cannot be reconciled with generally accepted medical literature. There is no reliable medical evidence that the following processes are causative in the constellation of injuries of AHT: cerebral sinovenous thrombosis, hypoxic-ischemic injury, lumbar puncture or dysphagic choking/vomiting. There is no substantiation, at a time remote from birth, that an asymptomatic birth-related subdural hemorrhage can result in rebleeding and sudden collapse. Further, a diagnosis of AHT is a medical conclusion, not a legal determination of the intent of the perpetrator or a diagnosis of murder. We hope that this consensus document reduces confusion by recommending to judges and jurors the tools necessary to distinguish genuine evidence-based opinions of the relevant medical community from legal arguments or etiological speculations that are unwarranted by the clinical findings, medical evidence and evidence-based literature

    Determinants of synaptic information transfer: From Ca2+ binding proteins to Ca2+ signaling domains

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    The cytoplasmic free Ca2+ concentration ([Ca2+]i) is a key determinant of neuronal information transfer and processing. It controls a plethora of fundamental processes, including transmitter release and the induction of synaptic plasticity. This enigmatic second messenger conveys its wide variety of actions by binding to a subgroup of Ca2+ binding proteins (CaBPs) known as “Ca2+ sensors”. Well known examples of Ca2+ sensors are Troponin-C in skeletal muscle, Synaptotagmin in presynaptic terminals, and Calmodulin (CaM) in all eukaryotic cells. Since the levels of [Ca2+]i directly influence the potency of Ca2+ sensors, the Ca2+ concentration is tightly controlled by several mechanisms including another type of Ca2+ binding proteins, the Ca2+ buffers. Prominent examples of Ca2+ buffers include Parvalbumin (PV), Calbindin-D28k (CB) and Calretinin (CR), although for the latter two Ca2+ sensor functions were recently also suggested. Ca2+ buffers are distinct from sensors by their purely buffering action, i.e. they influence the spatio-temporal extent of Ca2+ signals, without directly binding downstream target proteins. Details of their action depend on their binding kinetics, mobility, and concentration. Thus, neurons can control the range of action of Ca2+ by the type and concentration of CaBPs expressed. Since buffering strongly limits the range of action of free Ca2+, the structure of the Ca2+ signaling domain and the topographical relationships between the sites of Ca2+ influx and the location of the Ca2+ sensors are central determinants in neuronal information processing. For example, postsynaptic dendritic spines act to compartmentalize Ca2+ depending on their geometry and expression of CaBPs, thereby influencing dendritic integration. At presynaptic sites it has been shown that tight, so called nanodomain coupling between Ca2+ channels and the sensor for vesicular transmitter release increases speed and reliability of synaptic transmission. Vice versa, the influence of an individual CaBP on information processing depends on the topographical relationships within the signaling domain. If e.g. source and sensor are very close, only buffers with rapid binding kinetics can interfere with signaling. This Research Topic contains a collection of work dealing with the relationships between different [Ca2+]i controlling mechanisms in the structural context of synaptic sites and their functional implications for synaptic information processing as detailed in the Editorial
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