Articles de revues : « Cosmic ray direct detection »

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Putze, Antje. « Direct cosmic-ray detection ». Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment 662 (janvier 2012) : S157—S163. http://dx.doi.org/10.1016/j.nima.2010.11.133.

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CHEN, CHUAN-REN. « MODEL-INDEPENDENT STUDIES OF DARK MATTER ». International Journal of Modern Physics D 20, n^o 08 (15 août 2011) : 1441–51. http://dx.doi.org/10.1142/s0218271811019621.

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The excess in cosmic-ray positrons and electrons observed by PAMELA, ATIC, PPB-BET and Fermi can be explained by dark matter decay or annihilation. On the other hand, the negative results from CDMS II and XENON direct detections of dark matter put an upper limit on the elastic-scattering cross section between dark matter and nucleon. We adopted model-independent approaches to study dark matter in cosmic-ray electrons, gamma-ray, relic density, direct detection experiments and LHC. We studied the distribution of the cosmic-ray electron flux observed at the Earth and found that it can reflect the initial energy spectrum of electrons generated from dark matter decay or annihilation even after propagation. We also derive constraints on the decay rate of dark matter into various two-body final states using Fermi and HESS gamma-ray data. We found that the μ+μ- or τ+τ- final state is favored in order to simultaneously explain electron excess and meet all gamma-ray constraints. Finally, we examined various tree-level induced operators of dimension six and constrain them using the current experimental data, including the WMAP data of the relic abundance and CDMS II direct detection of the spin-independent scattering. The implication of LHC search is also explored.

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Vernstrom, T., G. Heald, F. Vazza, T. J. Galvin, J. L. West, N. Locatelli, N. Fornengo et E. Pinetti. « Discovery of magnetic fields along stacked cosmic filaments as revealed by radio and X-ray emission ». Monthly Notices of the Royal Astronomical Society 505, n^o 3 (11 mai 2021) : 4178–96. http://dx.doi.org/10.1093/mnras/stab1301.

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ABSTRACT Diffuse filaments connect galaxy clusters to form the cosmic web. Detecting these filaments could yield information on the magnetic field strength, cosmic ray population, and temperature of intercluster gas; yet, the faint and large-scale nature of these bridges makes direct detections very challenging. Using multiple independent all-sky radio and X-ray maps we stack pairs of luminous red galaxies as tracers for cluster pairs. For the first time, we detect an average surface brightness between the clusters from synchrotron (radio) and thermal (X-ray) emission with ≳5σ significance, on physical scales larger than observed to date (${\ge}3$ Mpc). We obtain a synchrotron spectral index of α ≃ −1.0 and estimates of the average magnetic field strength of $30\,\mathrm{ nG} \le B \le 60 $ nG, derived from both equipartition and inverse-Compton arguments, implying a 5–15 per cent degree of field regularity when compared with Faraday rotation measure estimates. While the X-ray detection is inline with predictions, the average radio signal comes out higher than predicted by cosmological simulations and dark matter annihilation and decay models. This discovery demonstrates that there are connective structures between mass concentrations that are significantly magnetized, and the presence of sufficient cosmic rays to produce detectable synchrotron radiation.

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Tanimori, Toru. « Detection of TeV Gamma Rays from SN1006 ». Symposium - International Astronomical Union 188 (1998) : 121–24. http://dx.doi.org/10.1017/s0074180900114585.

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In spite of the recent progress of high energy gamma-ray astronomy, there still remains quite unclear and important problem about the origin of cosmic rays. Supernova remnants (SNRs) are the favoured site for cosmic rays up to 1016 eV, as they satisfy the requirements such as an energy input rate. But direct supporting evidence is sparse. Recently intense non-thermal X-ray emission from the rims of the Type Ia SNR SN1006 (G327.6+14.6) has been observed by ASCA (Koyama et al. 1995)and ROSAT (Willingale et al. 1996), which is considered, by attributing the emission to synchrotron radiation, to be strong evidence of shock acceleration of high energy electrons up to ~100 TeV. If so, TeV gamma rays would also be expected from inverse Compton scattering (IC) of low energy photons (mostly attributable to the 2.7 K cosmic background photons) by these electrons. By assuming the magnetic field strength (B) in the emission region of the SNR, several theorists (Pohl 1996; Mastichiadis 1996; Mastichiadis & de Jager 1996; Yoshida & Yanagita 1997) calculated the expected spectra of TeV gamma rays using the observed radio/X-ray spectra. Observation of TeV gamma rays would thus provide not only the further direct evidence of the existence of very high energy electrons but also the another important information such as the strength of the magnetic field and diffusion coefficient of the shock acceleration. With this motivation, SN1006 was observed by the CANGAROO imaging air Cerenkov telescope in 1996 March and June, also 1997 March and April.

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Morlino, Giovanni. « Supernova Remnant-Cosmic Ray connection : a modern view ». Proceedings of the International Astronomical Union 12, S331 (février 2017) : 230–41. http://dx.doi.org/10.1017/s1743921317004793.

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AbstractThe Cosmic Ray (CR) physics has entered a new era driven by high precision measurements coming from direct detection (especially AMS-02 and PAMELA) and also from gamma-ray observations (Fermi-LAT). In this review we focus our attention on how such data impact the understanding of the supernova remnant paradigm for the origin of CRs. In particular we discuss advancement in the field concerning the three main stages of the CR life: the acceleration process, the escape from the sources and the propagation throughout the Galaxy. We show how the new data reveal a phenomenology richest than previously thought that could even challenge the current understanding of CR origin.

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Perrina, Chiara. « The future of the high energy cosmic ray detection : HERD ». EPJ Web of Conferences 209 (2019) : 01040. http://dx.doi.org/10.1051/epjconf/201920901040.

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The High Energy cosmic-Radiation Detection (HERD) facility will be one of the space astronomy payloads on board the future Chinese space station. The ambitious aim of HERD is the direct detection of cosmic rays towards the “knee” region (~ 1 PeV), with a detector able to measure electrons, photons and nuclei with an excellent energy resolution (1% for electrons and photons at 200 GeV and 20% for nuclei at 100 GeV - PeV), an acceptance 10 times the one of present generation missions (~ 1 m2 sr), and long life-time (> 10 years). The primary objectives of HERD are the indirect search for dark matter particles and the precise measurement of energy distribution and composition of cosmic rays from 30 GeV up to a few PeV, determining the origin of the “knee” structure of the spectrum. Furthermore, HERD will monitor the high energy gamma-ray sky from 500 MeV, observing gamma-ray bursts, active galactic nuclei, galactic microquasars, etc. HERD will be composed of a homogeneous calorimeter, surrounded by a particle tracker and a plastic scintillator detector. Two possible trackers are under study: a 5-side tracker made of silicon strip detectors and a 4-side scintillating fiber tracker with a silicon strip top tracker. The total volume of HERD will be (2.3 × 2.3 × 2.6) m3 with a weight of about 4 t. The HERD design, perspectives, expected performances in terms of energy sensitivity and acceptance will be presented in this contribution.

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Adriani, Oscar, Corrado Altomare, Giovanni Ambrosi, Philipp Azzarello, Felicia Carla Tiziana Barbato, Roberto Battiston, Bertrand Baudouy et al. « Design of an Antimatter Large Acceptance Detector In Orbit (ALADInO) ». Instruments 6, n^o 2 (11 mai 2022) : 19. http://dx.doi.org/10.3390/instruments6020019.

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A new generation magnetic spectrometer in space will open the opportunity to investigate the frontiers in direct high-energy cosmic ray measurements and to precisely measure the amount of the rare antimatter component in cosmic rays beyond the reach of current missions. We propose the concept for an Antimatter Large Acceptance Detector In Orbit (ALADInO), designed to take over the legacy of direct measurements of cosmic rays in space performed by PAMELA and AMS-02. ALADInO features technological solutions conceived to overcome the current limitations of magnetic spectrometers in space with a layout that provides an acceptance larger than 10 m2 sr. A superconducting magnet coupled to precision tracking and time-of-flight systems can provide the required matter–antimatter separation capabilities and rigidity measurement resolution with a Maximum Detectable Rigidity better than 20 TV. The inner 3D-imaging deep calorimeter, designed to maximize the isotropic acceptance of particles, allows for the measurement of cosmic rays up to PeV energies with accurate energy resolution to precisely measure features in the cosmic ray spectra. The operations of ALADInO in the Sun–Earth L2 Lagrangian point for at least 5 years would enable unique revolutionary observations with groundbreaking discovery potentials in the field of astroparticle physics by precision measurements of electrons, positrons, and antiprotons up to 10 TeV and of nuclear cosmic rays up to PeV energies, and by the possible unambiguous detection and measurement of low-energy antideuteron and antihelium components in cosmic rays.

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Coogan, Adam, Benjamin V. Lehmann et Stefano Profumo. « Connecting direct and indirect detection with a dark spike in the cosmic-ray electron spectrum ». Journal of Cosmology and Astroparticle Physics 2019, n^o 10 (28 octobre 2019) : 063. http://dx.doi.org/10.1088/1475-7516/2019/10/063.

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Urban, Federico R., Stefano Camera et David Alonso. « Detecting ultra-high-energy cosmic ray anisotropies through harmonic cross-correlations ». Astronomy & ; Astrophysics 652 (août 2021) : A41. http://dx.doi.org/10.1051/0004-6361/202038459.

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We propose an observable for ultra-high-energy cosmic ray (UHECR) physics: the harmonic-space cross-correlation power spectrum between the arrival directions of UHECRs and the large-scale cosmic structure mapped by galaxies. This cross-correlation has not yet been considered in the literature, and it permits a direct theoretical modelling of the main astrophysical components. We describe the expected form of the cross-correlation and show how, if the distribution of UHECR sources traces the large-scale cosmic structure, it could be easier to detect with current data than the UHECR auto-correlation. Moreover, the cross-correlation is more sensitive to UHECR anisotropies on smaller angular scales, it is more robust to systematic uncertainties, and it could be used to determine the redshift distribution of UHECR sources, making it a valuable tool for determining their origins and properties.

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Cheek, Andrew. « Dark Matter Physics in Neutrino Telescopes and Neutrino Physics in Dark Matter Detectors ». Journal of Physics : Conference Series 2156, n^o 1 (1 décembre 2021) : 012215. http://dx.doi.org/10.1088/1742-6596/2156/1/012215.

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Abstract It is often the case that experiments built with a focus on a specific fundamental question are sensitive to a wider range of physical phenomena. In this proceedings I discuss two cases where new insights will come from experiments that have a different primary purpose. First, presents results from Ref. [1], which assesses what simple dark matter models will be uniquely probed by a upcoming Neutrino telescope inspired by KM3NeT. Given the existing constraints from γ-ray telescopes, measurements of the cosmic microwave background and direct dark matter detection, we focus on a secluded U(1)L μ − L γ model as particularly promising. Secondly, I present the results from Ref. [2], which describes how detecting solar neutrinos in direct dark matter detection experiments will be vital for confirming the possible U(1)L μ − L γ explanation of the anomalous magnetic moment of the muon.

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Abdollahi, S., F. Acero, M. Ackermann, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri et al. « Search for New Cosmic-Ray Acceleration Sites within the 4FGL Catalog Galactic Plane Sources ». Astrophysical Journal 933, n^o 2 (1 juillet 2022) : 204. http://dx.doi.org/10.3847/1538-4357/ac704f.

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Abstract Cosmic rays are mostly composed of protons accelerated to relativistic speeds. When those protons encounter interstellar material, they produce neutral pions, which in turn decay into gamma-rays. This offers a compelling way to identify the acceleration sites of protons. A characteristic hadronic spectrum, with a low-energy break around 200 MeV, was detected in the gamma-ray spectra of four supernova remnants (SNRs), IC 443, W44, W49B, and W51C, with the Fermi Large Area Telescope. This detection provided direct evidence that cosmic-ray protons are (re-)accelerated in SNRs. Here, we present a comprehensive search for low-energy spectral breaks among 311 4FGL catalog sources located within 5° from the Galactic plane. Using 8 yr of data from the Fermi Large Area Telescope between 50 MeV and 1 GeV, we find and present the spectral characteristics of 56 sources with a spectral break confirmed by a thorough study of systematic uncertainty. Our population of sources includes 13 SNRs for which the proton–proton interaction is enhanced by the dense target material; the high-mass gamma-ray binary LS I+61 303; the colliding wind binary η Carinae; and the Cygnus star-forming region. This analysis better constrains the origin of the gamma-ray emission and enlarges our view to potential new cosmic-ray acceleration sites.

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Xia, Chen, Yan-Hao Xu et Yu-Feng Zhou. « Production and attenuation of cosmic-ray boosted dark matter ». Journal of Cosmology and Astroparticle Physics 2022, n^o 02 (1 février 2022) : 028. http://dx.doi.org/10.1088/1475-7516/2022/02/028.

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Abstract Light sub-GeV halo dark matter (DM) particles up-scattered by high-energy cosmic-rays (CRs) (referred to as CRDM) can be energetic and become detectable by conventional DM direct detection experiments. We perform a refined analysis on the exclusion bounds of the spin-independent DM-nucleon scattering cross section σχ p in this approach. For the exclusion lower bounds, we determine the parameter of the effective distance Deff for CRDM production using spatial-dependent CR fluxes and including the contributions from the major heavy CR nuclear species. We obtain Deff≃ 9 kpc for CRDM particles with kinetic energy above ∼ 1 GeV, which pushes the corresponding exclusion lower bounds down to σχ p∼ 4× 10-32 cm2 for DM particle mass at MeV scale and below. For the exclusion upper bounds from Earth attenuation, previous estimations neglecting the nuclear form factor leaded to typical exclusion upper bounds of σχ p∼𝒪(10-28) cm2 from the XENON1T data. Using both the analytic and numerical approaches, we show that for CRDM particles, the presence of the nuclear form factor strongly suppresses the effect of Earth attenuation. Consequently, the cross section that can be excluded by the XENON1T data can be a few orders of magnitude higher, which closes the gap in the cross sections excluded by the XENON1T experiment and that by the astrophysical measurements such that for the cosmic microwave background (CMB), galactic gas cloud cooling, and structure formation, etc..

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Pacini, Lorenzo, et Nicola Mori. « CaloCube and “Tracker In Calorimeter” projects for the direct measurement of high energy charged astro-particles and gamma rays. » EPJ Web of Conferences 209 (2019) : 01039. http://dx.doi.org/10.1051/epjconf/201920901039.

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Measurements of high energy cosmic rays in the “knee” region (about 1015 eV) are currently available only with ground detectors: new observations of cosmic particles up to these energies with direct measurements are one of the main goals of the next generation space experiments. To achieve those aims, a large acceptance, good energy resolution and particle identification are needed. CaloCube is the design of a space borne calorimeter which is capable to accept particles coming from any direction, increasing the acceptance with respect to traditional telescopes. A good performance for both hadronic and electromagnetic showers is achieved with a 3-D sampling capability: the basic picture of CaloCube is a cubic homogeneous calorimeter which consists of cubic scintillating crystals. MC simulations, concerning different materials and geometrical configurations, and several beam tests with different versions of the CaloCube prototype have been employed to optimize both the detector design and the data analysis method. Taking advantage of the CaloCube project, the space experiment HERD (“High Energy Cosmic Radiation Detection”) will include a large acceptance cubic calorimeter with cubic LYSO crystals. It will be installed on-board of the Chinese space station around 2025. Beside the charged particle observations, high energy gamma-rays provide direct information about the galactic cosmic ray sources. A new project named “Tracker In Calorimeter” (TIC) was approved by INFN in 2017 with the main purpose of the optimization of the calorimeter design for the reconstruction of the gamma-ray direction, without the requirement of additional not homogeneous pre-shower detector. A TIC prototype was recently assembled and tested at the PS-CERN and SPS-CERN accelerators.

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Cebrián, Susana. « Cosmogenic activation of materials ». International Journal of Modern Physics A 32, n^o 30 (30 octobre 2017) : 1743006. http://dx.doi.org/10.1142/s0217751x17430060.

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Experiments looking for rare events like the direct detection of dark matter particles, neutrino interactions or the nuclear double beta decay are operated deep underground to suppress the effect of cosmic rays. But, the production of radioactive isotopes in materials due to previous exposure to cosmic rays is a hazard when ultra-low background conditions are required. In this context, the generation of long-lived products by cosmic nucleons has been studied for many detector media and for other materials commonly used. Here, the main results obtained on the quantification of activation yields on the Earth’s surface will be summarized, considering both measurements and calculations following different approaches. The isotope production cross-sections and the cosmic ray spectrum are the two main ingredients when calculating this cosmogenic activation; the different alternatives for implementing them will be discussed. Activation that can take place deep underground mainly due to cosmic muons will be briefly commented too. Presently, the experimental results for the cosmogenic production of radioisotopes are scarce and discrepancies between different calculations are important in many cases, but the increasing interest on this background source which is becoming more and more relevant can help to change this situation.

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Adriani, O., E. Berti, P. Betti, G. Bigongiari, L. Bonechi, M. Bongi, S. Bottai et al. « Light yield non-proportionality of inorganic crystals and its effect on cosmic-ray measurements ». Journal of Instrumentation 17, n^o 08 (1 août 2022) : P08014. http://dx.doi.org/10.1088/1748-0221/17/08/p08014.

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Abstract The multi-TeV energy region of the cosmic-ray spectra has been recently explored by direct detection experiments that used calorimetric techniques to measure the energy of the cosmic particles. Interesting spectral features have been observed in both all-electron and nuclei spectra. However, the interpretation of the results is compromised by the disagreements between the data obtained from the various experiments, that are not reconcilable with the quoted experimental uncertainties. Understanding the reason for the discrepancy among the measurements is of fundamental importance in view of the forthcoming high-energy cosmic-ray experiments planned for space, as well as for the correct interpretation of the available results. The purpose of this work is to investigate the possibility that a systematic effect may derive from the non-proportionality of the light response of inorganic crystals, typically used in high-energy calorimetry due to their excellent energy-resolution performance. The main reason for the non-proportionality of the crystals is that scintillation light yield depends on ionisation density. Experimental data obtained with ion beams were used to characterize the light response of various scintillator materials. The obtained luminous efficiencies were used as input of a Monte Carlo simulation to perform a comparative study of the effect of the light-yield non-proportionality on the detection of high-energy electromagnetic and hadronic showers. The result of this study indicates that, if the calorimeter response is calibrated by using the energy deposit of minimum ionizing particles, the measured shower energy might be affected by a significant systematic shift, at the level of few percent, whose sign and magnitude depend specifically on the type of scintillator material used.

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Coimbra-Araújo, Carlos H., et Rita C. Anjos. « Producing ultra high energy cosmic rays from AGN magnetic luminosity ». Proceedings of the International Astronomical Union 12, S324 (septembre 2016) : 207–10. http://dx.doi.org/10.1017/s1743921317000023.

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AbstractThe present work proposes a method to calculate the AGN magnetic luminosity fraction to be converted into ultra high energy cosmic rays (UHECRs) luminosities for nine UHECR AGN Seyfert sources based on the respective observation of gamma ray upper limits. The motivation for such calculation comes attached to the fact that a fraction of the magnetic luminosity (LB) produced by Kerr black holes in some AGNs can produce the necessary energy to accelerate UHECRs beyond the GZK limit, observed, e.g., by the Auger experiment. Nevertheless, the direct detection of those UHECRs has a lack of information about the direction of the source from where those cosmic rays are coming, since charged particles are deflected by the intergalactic magnetic field. Such problem arises alternative methods to evaluate the luminosity of UHECRs from the observation of upper limits during the propagation.

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Das, Saikat, Soebur Razzaque et Nayantara Gupta. « Cosmogenic gamma-ray and neutrino fluxes from blazars associated with IceCube events ». Astronomy & ; Astrophysics 658 (février 2022) : L6. http://dx.doi.org/10.1051/0004-6361/202142123.

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Context. Blazars constitute the vast majority of extragalactic γ-ray sources. They can also contribute a sizable fraction of the diffuse astrophysical neutrinos detected by IceCube. In the past few years, the real-time alert system of IceCube has led to the multiwavelength follow-up of very high-energy neutrino events of plausible astrophysical origin. Spatial and temporal coincidences of a number of these neutrino events with γ-ray blazars provide a unique opportunity to decipher cosmic-ray interactions in the relativistic jets. Aims. The aim of this work is to test if the γ-ray blazars associated with the IceCube neutrino events are also sources of ultra-high-energy cosmic rays (UHECRs; E > 1018 eV). Methods. Assuming that blazars accelerate UHECRs, we calculate the “guaranteed” contribution to the line-of-sight cosmogenic γ-ray and neutrino fluxes from four blazars associated with IceCube neutrino events. We compare these fluxes with the sensitivities of the upcoming γ-ray imaging telescopes, such as the CTA, and with the planned neutrino detectors, such as IceCube-Gen2. Results. We find that detection of the cosmogenic neutrino fluxes from the blazars TXS 0506+056, PKS 1502+106, and GB6 J1040+0617 would require UHECR luminosity ≳10 times the inferred neutrino luminosity from the associated IceCube events, with the maximum UHECR proton energy Ep, max ≈ 1020 eV. Cosmogenic γ-ray emission from blazars TXS 0506+056, 3HSP J095507.9 +355101, and GB6 J1040+0617 can be detected by the CTA if the UHECR luminosity is ≳10 times the neutrino luminosity inferred from the associated IceCube events and for Ep, max ≳ 1019 eV. Conclusions. Detection of cosmogenic neutrino and/or γ-ray flux(es) from blazars associated with IceCube neutrinos may lead to the first direct signature(s) of UHECR sources. Given their relatively low redshifts and hence total energetics, TXS 0506+056 and 3HSP J095507.9+355101 should be the prime targets for upcoming large neutrino and γ-ray telescopes.

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Ighina, L., A. Moretti, F. Tavecchio, A. Caccianiga, S. Belladitta, D. Dallacasa, R. Della Ceca, T. Sbarrato et C. Spingola. « Direct observation of an extended X-ray jet at z = 6.1 ». Astronomy & ; Astrophysics 659 (mars 2022) : A93. http://dx.doi.org/10.1051/0004-6361/202142676.

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We report on the direct observation of an extended X-ray jet in the z = 6.1 radio-loud active galactic nucleus PSO J030947.49+271757.31 from a deep Chandra X-ray observation (128 ksec). This detection represents the most distant kiloparsec-scale off-nuclear emission resolved in X-rays to date. The angular distance of the emission is ∼4″ (corresponding to ∼20 kpc at z = 6.1), along the same direction of the jet observed at parsec scales in previous VLBA high-resolution radio observations. Moreover, the 0.5–7.0 keV isophotes coincide with the extended radio emission as imaged by the VLA Sky Survey at 3 GHz. The rest-frame 2–10 keV luminosity of the extended component is L2 − 10 keV = 5.9 × 1044 erg s−1, about 8% of the core: this makes it one of the most luminous jets resolved in X-rays so far. Through spectral energy distribution modelling we find that this emission can be explained by the inverse Compton interaction with the photons of the cosmic microwave background, assuming that the jet’s physical parameters are similar to those in the local Universe. At the same time, we find that the radiation produced by a putative population of high-energy electrons through the synchrotron process observed at low redshift is quenched at high redshift, hence becoming negligible.

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Bulla, Mattia, Michael W. Coughlin, Suhail Dhawan et Tim Dietrich. « Multi-Messenger Constraints on the Hubble Constant through Combination of Gravitational Waves, Gamma-Ray Bursts and Kilonovae from Neutron Star Mergers ». Universe 8, n^o 5 (21 mai 2022) : 289. http://dx.doi.org/10.3390/universe8050289.

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The simultaneous detection of gravitational waves and light from the binary neutron star merger GW170817 led to independent measurements of distance and redshift, providing a direct estimate of the Hubble constant H0 that does not rely on a cosmic distance ladder, nor assumes a specific cosmological model. By using gravitational waves as “standard sirens”, this approach holds promise to arbitrate the existing tension between the H0 value inferred from the cosmic microwave background and those obtained from local measurements. However, the known degeneracy in the gravitational-wave analysis between distance and inclination of the source led to a H0 value from GW170817 that was not precise enough to resolve the existing tension. In this review, we summarize recent works exploiting the viewing-angle dependence of the electromagnetic signal, namely the associated short gamma-ray burst and kilonova, to constrain the system inclination and improve on H0. We outline the key ingredients of the different methods, summarize the results obtained in the aftermath of GW170817 and discuss the possible systematics introduced by each of these methods.

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Malavasi, Nicola, Nabila Aghanim, Hideki Tanimura, Victor Bonjean et Marian Douspis. « Like a spider in its web : a study of the large-scale structure around the Coma cluster ». Astronomy & ; Astrophysics 634 (31 janvier 2020) : A30. http://dx.doi.org/10.1051/0004-6361/201936629.

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The Cosmic Web is a complex network of filaments, walls, and voids that represent the largest structures in the Universe. In this network, which is the direct result of structure formation, galaxy clusters occupy central positions that form the nodes and these are connected by filaments. In this work, we investigate the position in the Cosmic Web of one of the most well-known and best-studied clusters of galaxies, the Coma cluster. We make use of the Sloan Digital Sky Survey Data Release 7 Main Galaxy Sample and of the Discrete Persistent Structure Extractor to detect large-scale filaments around the Coma cluster and analyse the properties of the Cosmic Web. We study the network of filaments around Coma in a region of 75 Mpc in radius. We find that the Coma cluster has a median connectivity of 2.5, in agreement with measurements from clusters of similar mass in the literature as well as with what is expected from numerical simulations. Coma is indeed connected to three secure filaments which connect it to Abell 1367 and to several other clusters in the field. The location of these filaments in the vicinity of Coma is consistent with features detected in the X-ray, as well as the likely direction of infall of galaxies, such as for example NGC 4839. The overall picture that emerges of the Coma cluster is that of a highly connected structure occupying a central position as a dense node of the Cosmic Web. We also find a tentative detection, at 2.1σ significance, of the filaments in the SZ signal.

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Marchili, N., G. Piano, M. Cardillo, A. Giuliani, S. Molinari et M. Tavani. « A new gamma-ray source unveiled by AGILE in the region of Orion ». Astronomy & ; Astrophysics 615 (juillet 2018) : A82. http://dx.doi.org/10.1051/0004-6361/201732333.

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Context. Diffuse galactic γ-ray emission is produced by the interaction of cosmic rays (CRs) with the interstellar environment. The study of γ-ray emission is therefore a powerful tool that can be used to investigate the origin of CRs and the processes through which they are accelerated. Aims. Our aim is to gain deeper insights into the nature of γ-ray emission in the region of Orion, which is one of the best studied sites of ongoing star formation, by analysing data from the AGILE satellite. Because of the large amount of interstellar medium (ISM) present in it, the diffuse γ-ray emission expected from the Orion region is relatively high. Its separation from the galactic plane also ensures a very small contribution from foreground or background emission, which makes it an ideal site for studying the processes of particle acceleration in star-forming environments. Methods. The AGILE data are modelled through a template that quantifies the γ-ray diffuse emission expected from atomic and molecular hydrogen. Other sources of emission, such as inverse Compton (IC) scattering in interstellar radiation fields (ISRF) and extragalactic background, can be modelled as an isotropic contribution. Results. Gamma-ray emission exceeding the amount expected by the diffuse emission model is detected with a high level of significance. The main excess is in the high-longitude part of Orion A, which confirms previous results from the Fermi Large Area Telescope. A thorough analysis of this feature suggests a connection between the observed γ-ray emission and the B0.5 Ia star κ Orionis. Conclusions. We present the results of the investigation of γ-ray diffuse galactic emission from the region of Orion. The comparison between modelled and observed emission points towards the existence of higher-than-expected γ-ray flux from a 1° radius region centred in κ Orionis, compatible with the site where stellar wind collides with the ISM. Scattering on dark gas and cosmic-ray acceleration at the shock between the two environments are both discussed as possible explanations, with the latter hypothesis being supported by the hardness of the energy spectrum of the emission. If confirmed, this would be the first direct detection of γ-ray emission from the interaction between ISM and a single star’s stellar wind.

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Pérez de los Heros, Carlos. « Status, Challenges and Directions in Indirect Dark Matter Searches ». Symmetry 12, n^o 10 (8 octobre 2020) : 1648. http://dx.doi.org/10.3390/sym12101648.

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Indirect searches for dark matter are based on detecting an anomalous flux of photons, neutrinos or cosmic-rays produced in annihilations or decays of dark matter candidates gravitationally accumulated in heavy cosmological objects, like galaxies, the Sun or the Earth. Additionally, evidence for dark matter that can also be understood as indirect can be obtained from early universe probes, like fluctuations of the cosmic microwave background temperature, the primordial abundance of light elements or the Hydrogen 21-cm line. The techniques needed to detect these different signatures require very different types of detectors: Air shower arrays, gamma- and X-ray telescopes, neutrino telescopes, radio telescopes or particle detectors in balloons or satellites. While many of these detectors were not originally intended to search for dark matter, they have proven to be unique complementary tools for direct search efforts. In this review we summarize the current status of indirect searches for dark matter, mentioning also the challenges and limitations that these techniques encounter.

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Papadopoulos, Georgios. « Using scientific-grade CCDs for the direct detection of dark matter with the DAMIC-M experiment ». Journal of Instrumentation 17, n^o 08 (1 août 2022) : C08004. http://dx.doi.org/10.1088/1748-0221/17/08/c08004.

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Abstract The DAMIC-M [1] project is devoted to the exploration of the hidden sector and the search for light dark matter particles using Charge-Coupled Devices (CCDs). It follows the DAMIC at SNOLAB [2] experiment which pioneered the detection of new particles through their interaction with the nucleus or the electrons of the bulk silicon of fully depleted CCDs. A kilogram-sized target mass will be installed at the Modane underground laboratory (LSM, France) which offers an excellent low background environment for rare-event search. DAMIC-M detectors demonstrate several technological advancements including the implementation of the skipper technique, and custom front-end control and read-out electronics. Skipper CCDs can perform multiple non-destructive measurements of the pixel charge which can lead to a read-out noise of a fraction of an electron. With a 15 μm × 15 μm pixel area, 675 μm thickness and the ability of 3D reconstruction using the diffusion of the particle track, the spatial resolution of our CCDs allows for the follow-up of radioactive chains, a powerful tool to discriminate genuine particle interaction from in situ radioactive decays. Together with an extremely careful fabrication procedure that controls the contaminant and the generation of bulk radioactive contamination by cosmic ray spallation, the single electron resolution will guarantee a detection energy threshold of only a few eVs, pushing the sensitivity of DAMIC-M by at least one order of magnitude better than previous experiments. I will present the current status of DAMIC-M describing our technological challenges and the solutions we have adopted. I will introduce our method to measure and mitigate the bulk radioactive contamination and discuss the ongoing assembly of a prototype detector, the Low Background Chamber (LBC), aiming at validating our design options.

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Adriani, O., M. Antonelli, A. Basti, E. Berti, P. Betti, G. Bigongiari, L. Bonechi et al. « Development of the photo-diode subsystem for the HERD calorimeter double-readout ». Journal of Instrumentation 17, n^o 09 (1 septembre 2022) : P09002. http://dx.doi.org/10.1088/1748-0221/17/09/p09002.

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Abstract The measurement of cosmic-ray individual spectra provides unique information regarding the origin and propagation of astro-particles. Due to the limited acceptance of current space experiments, protons and nuclei around the “knee” region (∼ 1 PeV) can only be observed by ground based experiments. Thanks to an innovative design, the High Energy cosmic-Radiation Detection (HERD) facility will allow direct observation up to this energy region: the instrument is mainly based on a 3D segmented, isotropic and homogeneous calorimeter which properly measures the energy of particles coming from each direction and it will be made of about 7500 LYSO cubic crystals. The read-out of the scintillation light is done with two independent systems: the first one based on wave-length shifting fibers coupled to Intensified scientific CMOS cameras, the second one is made of two photo-diodes with different active areas connected to a custom front-end electronics. This photo-diode system is designed to achieve a huge dynamic range, larger than 107, while having a small power consumption, few mW per channel. Thanks to a good signal-to-noise ratio, the capability of a proper calibration, by using signals of both non-interacting and showering particles, is also guaranteed. In this paper, the current design and the performance obtained by several tests of the photo-diode read-out system are discussed.

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Walker, Mark, et Mark Wardle. « The Cloudy Universe ». Publications of the Astronomical Society of Australia 16, n^o 3 (1999) : 262–72. http://dx.doi.org/10.1071/as99262.

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AbstractModelling of extreme scattering events suggests that the Galaxy's dark matter is an undetected population of cold, AU-sized, planetary-mass gas clouds. None of the direct observational constraints on this picture—thermal/non-thermal emission, extinction and lensing—are problematic. The theoretical situation is less comfortable, but still satisfactory. Galactic clouds can survive in their current condition for billions of years, but we do not have a firm description for either their origin or their evolution to the present epoch. We hypothesise that the proto-clouds formed during the quark–hadron phase transition, thereby introducing the inhomogeneity necessary for compatibility with light element nucleosynthesis in a purely baryonic universe. We outline the prospects for directly detecting the inferred cloud population. The most promising signatures are cosmic-ray-induced Hα emission from clouds in the solar neighbourhood, optical and X-ray flashes arising from cloud–cloud collisions, ultraviolet extinction, and three varieties of lensing phenomena.

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Takada, Atsushi, Taito Takemura, Kei Yoshikawa, Yoshitaka Mizumura, Tomonori Ikeda, Yuta Nakamura, Ken Onozaka et al. « First Observation of the MeV Gamma-Ray Universe with Bijective Imaging Spectroscopy Using the Electron-tracking Compton Telescope on Board SMILE-2+ ». Astrophysical Journal 930, n^o 1 (28 avril 2022) : 6. http://dx.doi.org/10.3847/1538-4357/ac6103.

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Abstract MeV gamma-rays provide a unique window for the direct measurement of line emissions from radioisotopes, but observations have made little significant progress since COMPTEL on board the Compton Gamma-ray Observatory (CGRO). To observe celestial objects in this band, we are developing an electron-tracking Compton camera (ETCC) that realizes both bijective imaging spectroscopy and efficient background reduction gleaned from the recoil-electron track information. The energy spectrum of the observation target can then be obtained by a simple ON–OFF method using a correctly defined point-spread function on the celestial sphere. The performance of celestial object observations was validated on the second balloon SMILE-2+ , on which an ETCC with a gaseous electron tracker was installed that had a volume of 30 × 30 × 30 cm3. Gamma-rays from the Crab Nebula were detected with a significance of 4.0σ in the energy range 0.15–2.1 MeV with a live time of 5.1 hr, as expected before launch. Additionally, the light curve clarified an enhancement of gamma-ray events generated in the Galactic center region, indicating that a significant proportion of the final remaining events are cosmic gamma-rays. Independently, the observed intensity and time variation were consistent with the prelaunch estimates except in the Galactic center region. The estimates were based on the total background of extragalactic diffuse, atmospheric, and instrumental gamma-rays after accounting for the variations in the atmospheric depth and rigidity during the level flight. The Crab results and light curve strongly support our understanding of both the detection sensitivity and the background in real observations. This work promises significant advances in MeV gamma-ray astronomy.

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Yang, Guang, Vicente Estrada-Carpenter, Casey Papovich, Fabio Vito, Jonelle L. Walsh, Zhiyuan Yao et Feng Yuan. « Do Current X-Ray Observations Capture Most of the Black-hole Accretion at High Redshifts ? » Astrophysical Journal 921, n^o 2 (1 novembre 2021) : 170. http://dx.doi.org/10.3847/1538-4357/ac2233.

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Abstract The cosmic black hole accretion density (BHAD) is critical for our understanding of the formation and evolution of supermassive black holes (BHs). However, at high redshifts (z > 3), X-ray observations report BHADs significantly (∼10 times) lower than those predicted by cosmological simulations. It is therefore paramount to constrain the high-z BHAD using independent methods other than direct X-ray detections. The recently established relation between star formation rate and BH accretion rate among bulge-dominated galaxies provides such a chance, as it enables an estimate of the BHAD from the star formation histories (SFHs) of lower-redshift objects. Using the CANDELS Lyα Emission At Reionization (CLEAR) survey, we model the SFHs for a sample of 108 bulge-dominated galaxies at z = 0.7–1.5, and further estimate the BHAD contributed by their high-z progenitors. The predicted BHAD at z ≈ 4–5 is consistent with the simulation-predicted values, but higher than the X-ray measurements (by ≈3–10 times at z = 4–5). Our result suggests that the current X-ray surveys could be missing many heavily obscured Compton-thick active galactic nuclei (AGNs) at high redshifts. However, this BHAD estimation assumes that the high-z progenitors of our z = 0.7–1.5 sample remain bulge-dominated where star formation is correlated with BH cold-gas accretion. Alternatively, our prediction could signify a stark decline in the fraction of bulges in high-z galaxies (with an associated drop in BH accretion). JWST and Origins will resolve the discrepancy between our predicted BHAD and the X-ray results by constraining Compton-thick AGN and bulge evolution at high redshifts.

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DeGraf, C., et D. Sijacki. « Cosmological simulations of massive black hole seeds : predictions for next-generation electromagnetic and gravitational wave observations ». Monthly Notices of the Royal Astronomical Society 491, n^o 4 (18 décembre 2019) : 4973–92. http://dx.doi.org/10.1093/mnras/stz3309.

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ABSTRACT We study how statistical properties of supermassive black holes depend on the frequency and conditions for massive seed formation in cosmological simulations of structure formation. We develop a novel method to recalculate detailed growth histories and merger trees of black holes within the framework of the Illustris simulation for several seed formation models, including a physically motivated model where black hole seeds only form in progenitor galaxies that conform to the conditions for direct collapse black hole formation. While all seed models considered here are in a broad agreement with present observational constraints on black hole populations from optical, UV, and X-ray studies, we find that they lead to widely different black hole number densities and halo occupation fractions, which are currently observationally unconstrained. In terms of future electromagnetic spectrum observations, the faint-end quasar luminosity function and the low-mass-end black hole–host galaxy scaling relations are very sensitive to the specific massive seed prescription. Specifically, the direct collapse model exhibits a seeding efficiency that decreases rapidly with cosmic time and produces much fewer black holes in low-mass galaxies, in contrast to the original Illustris simulation. We further find that the total black hole merger rate varies by more than one order of magnitude for different seed models, with the redshift evolution of the chirp mass changing as well. Supermassive black hole merger detections with LISA and International Pulsar Timing Array may hence provide the most direct means of constraining massive black hole seed formation in the early Universe.

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Lazar, Alexandres, et Volker Bromm. « Probing the initial mass function of the first stars with transients ». Monthly Notices of the Royal Astronomical Society 511, n^o 2 (28 janvier 2022) : 2505–14. http://dx.doi.org/10.1093/mnras/stac176.

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ABSTRACT The emergence of the first, so-called Population III (Pop III), stars shaped early cosmic history in ways that crucially depends on their initial mass function (IMF). However, because of the absence of direct observational constraints, the detailed IMF remains elusive. Nevertheless, numerical simulations agree in broad terms that the first stars were typically massive and should often end their lives in violent, explosive deaths. These fates include extremely luminous pair-instability supernovae (PISNe) and bright gamma-ray bursts (GRBs), the latter arising from the collapse of rapidly rotating progenitor stars into black holes. These high-redshift transients are expected to be within the detection limits of upcoming space telescope missions, allowing to place effective constraints on the shape of the primordial IMF that is not easily accessible with other probes. This paper presents a framework to probe the Pop III IMF, utilizing the cosmological source densities of high-redshift PISNe and GRBs. Considering these transients separately could provide useful constraints on the Pop III IMF, but tighter bounds are obtainable by combining PISN and GRB counts. This combined diagnostic is more robust as it is independent of the underlying Pop III star formation rate density, an unknown prior. Future surveys promise to capture most high-redshift GRBs across the entire sky, but high-redshift PISN searches with future telescopes, e.g. Roman Space Telescope, will likely be substantially incomplete. Nevertheless, we demonstrate that even such lower bounds on the PISN count will be able to provide key constraints on the primordial IMF, in particular, if it is top-heavy or not.

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Picozza, P., P. Spillantini et L. Marcelli. « Cosmic Ray Direct Measurements ». Nuclear and Particle Physics Proceedings 297-299 (avril 2018) : 207–15. http://dx.doi.org/10.1016/j.nuclphysbps.2018.07.030.

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Picozza, Piergiorgio, et Laura Marcelli. « Cosmic ray direct measurements ». Rendiconti Lincei. Scienze Fisiche e Naturali 30, S1 (24 janvier 2019) : 165–70. http://dx.doi.org/10.1007/s12210-019-00764-1.

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Tapadar, Ananya, Sougata Ganguly et Sourov Roy. « Non-adiabatic evolution of dark sector in the presence of U(1)_{L_μ} – _{L_τ} gauge symmetry ». Journal of Cosmology and Astroparticle Physics 2022, n^o 05 (1 mai 2022) : 019. http://dx.doi.org/10.1088/1475-7516/2022/05/019.

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Abstract In secluded dark sector scenario, the connection between the visible and the dark sector can be established through a portal coupling and its presence opens up the possibility of non-adiabatic evolution of the dark sector. To study the non-adiabatic evolution of the dark sector, we have considered a U(1) Lμ – Lτ ⊗ U(1) X extension of the standard model (SM). Here the dark sector is charged only under U(1) X gauge symmetry whereas the SM fields are singlet under this symmetry. Due to the presence of tree-level kinetic mixing between U(1) X and U(1) Lμ – Lτ gauge bosons, the dark sector evolves non-adiabatically and thermal equilibrium between the visible and dark sector is governed by the portal coupling. Depending on the values of the portal coupling (ϵ), dark sector gauge coupling (gX ), mass of the dark matter (m χ) and mass of the dark vector boson (m Z'), we study the temperature evolution of the dark sector as well as the various non-equilibrium stages of the dark sector in detail. Furthermore we have also investigated the constraints on the model parameters from various laboratory and astrophysical searches. We have found that the parameter space for the non-adiabatic evolution of dark sector is significantly constrained for m Z' ≲ 100 MeV from the observations of beam dump experiments, stellar cooling etc. The relic density satisfied region of our parameter space is consistent with the bounds from direct detection, and self interaction of dark matter (SIDM) for the mass ratio r ≡ m Z'/m χ = 10-3 and these bounds will be more relaxed for larger values of r. However the constraints from measurement of diffuse γ-ray background flux and cosmic microwave background (CMB) anisotropy are strongest for r = 10-1 and for smaller values of r, they are not significant.

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VENTURA, SANDRO. « DATA REDUCTION TECHNIQUES AND EXTRACTION OF PHYSICS PARAMETERS IN THE ICARUS DETECTOR ». International Journal of Modern Physics C 05, n^o 05 (octobre 1994) : 843. http://dx.doi.org/10.1142/s0129183194000970.

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A liquid argon time projection chamber (LAr-TPC) working as an electronic bubblechamber, continually sensitive, self-triggering, able to provide 3-D imaging of any ionizing event together with a good calorimetric response was first proposed by Carlo Rubbia in 1977. In order to verify the feasibility of such a detector, the ICARUS collaboration started in 1985 an intensive R&D program aiming to solve the main technological problems. The satisfactory results obtained on small scale tests allowed us to start in 1989 the construction of a 3 ton prototype which is presently working at CERN under stable conditions without interruptions since May 1991, collecting events from cosmic rays and monochromatic gamma ray sources. The paper describes the working principles of such a detector, showing the results of the research program applied in the present prototype. Some emphasis is put into the description of the read-out apparatus, a custom designed VME-based multichannel waveform recorder. The huge number of channels and the high sampling rate essential to achieve the high resolution in the track detection make the data acquisition architecture a crucial point for event detection rate and self-triggering capabilities. At present a. complete signal analysis is performed to define those parameters needed to tune up algorithms and filtering methods that will become necessary in the future step of the ICARUS detector (hundred to thousands of tons of argon, i. e. tens of thousands of readout channels). A particular effort is made to optimize track localization algorithms, in order to achieve high efficiency data reduction by storing only those portions of signal which contain the track (thus lowering up to three orders of magnitude the event size) . From a human interface point of view, the data presentation relies on an event imaging very similar to the old fashioned bubble chambers. Besides from giving a direct feeling of what happens inside the detector, this kind of representations opens a way to the wide panorama of image processing applications: tasks as detail enhancement, pattern recognition or 3D reconstruction will helpfully inherit support from more general procedures.

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Peralta, Luis, et Florbela Rego. « Cosmic ray detection made easy ». Physics Education 47, n^o 2 (20 février 2012) : 143–44. http://dx.doi.org/10.1088/0031-9120/47/2/f01.

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Boezio, Mirko, Riccardo Munini et Piergiorgio Picozza. « Cosmic ray detection in space ». Progress in Particle and Nuclear Physics 112 (mai 2020) : 103765. http://dx.doi.org/10.1016/j.ppnp.2020.103765.

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Sushchov, O., P. Homola, N. Dhital, Ł. Bratek, P. Poznański, T. Wibig, J. Zamora-Saa et al. « Cosmic-Ray Extremely Distributed Observatory : a global cosmic ray detection framework ». Advances in Astronomy and Space Physics 7, n^o 1-2 (2017) : 23–29. http://dx.doi.org/10.17721/2227-1481.7.23-29.

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The main objective of the Cosmic-Ray Extremely Distributed Observatory (CREDO) is the detection and analysis of extended cosmic ray phenomena, so-called super-preshowers (SPS), using existing as well as new infrastructure (cosmic-ray observatories, educational detectors, single detectors etc.). The search for ensembles of cosmic ray events initiated by SPS is yet an untouched ground, in contrast to the current state-of-the-art analysis, which is focused on the detection of single cosmic ray events. Theoretical explanation of SPS could be given either within classical (e.g., photon-photon interaction) or exotic (e.g., Super Heavy Dark Matter decay or annihilation) scenarios, thus detection of SPS would provide a better understanding of particle physics, high energy astrophysics and cosmology. The ensembles of cosmic rays can be classified based on the spatial and temporal extent of particles constituting the ensemble. Some classes of SPS are predicted to have huge spatial distribution, a unique signature detectable only with a facility of the global size. Since development and commissioning of a completely new facility with such requirements is economically unwarranted and time-consuming, the global analysis goals are achievable when all types of existing detectors are merged into a worldwide network. The idea to use the instruments in operation is based on a novel trigger algorithm: in parallel to looking for neighbour surface detectors receiving the signal simultaneously, one should also look for spatially isolated stations clustered in a small time window. On the other hand, CREDO strategy is also aimed at an active engagement of a large number of participants, who will contribute to the project by using common electronic devices (e.g., smartphones), capable of detecting cosmic rays. It will help not only in expanding the geographical spread of CREDO, but also in managing a large manpower necessary for a more efficient crowd-sourced pattern recognition scheme to identify and classify SPS. A worldwide network of cosmic-ray detectors could not only become a unique tool to study fundamental physics, it will also provide a number of other opportunities, including space-weather or geophysics studies. Among the latter one has to list the potential to predict earthquakes by monitoring the rate of low energy cosmic-ray events. The diversity of goals motivates us to advertise this concept across the astroparticle physics community.

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Giller, Maria. « Cosmic ray composition from direct measurements ». Nuclear Physics B - Proceedings Supplements 52, n^o 3 (février 1997) : 164–65. http://dx.doi.org/10.1016/s0920-5632(96)00864-x.

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Hwang, W.-Y. P., et Bo-Qiang Ma. « Detection of cosmic neutrino clustering by cosmic ray spectra ». New Journal of Physics 7 (5 février 2005) : 41. http://dx.doi.org/10.1088/1367-2630/7/1/041.

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Brouwer, W., J. Pinfold, R. Soluk, B. McDonough, V. Pasek et Zheng Bao‐shan. « Student Projects in Cosmic Ray Detection ». Physics Teacher 47, n^o 8 (novembre 2009) : 494–98. http://dx.doi.org/10.1119/1.3246465.

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Ryazhskaya, O. G., L. V. Volkova et G. T. Zatsepin. « Direct cosmic ray muons and atmospheric neutrinos ». Nuclear Physics B - Proceedings Supplements 143 (juin 2005) : 527. http://dx.doi.org/10.1016/j.nuclphysbps.2005.01.192.

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Shibata, T. « Cosmic-ray spectrum and composition ; direct observation ». Il Nuovo Cimento C 19, n^o 5 (septembre 1996) : 713–36. http://dx.doi.org/10.1007/bf02506664.

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Kajita, Takaaki. « Detection of neutrinos and cosmic-ray particles ». Journal of the Visualization Society of Japan 19, Supplement1 (1999) : 13–18. http://dx.doi.org/10.3154/jvs.19.supplement1_13.

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Woźniak, Krzysztof W. « Detection of Cosmic-Ray Ensembles with CREDO ». EPJ Web of Conferences 208 (2019) : 15006. http://dx.doi.org/10.1051/epjconf/201920815006.

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One of the main objectives of cosmic-ray studies are precise measurements of the energy and chemical composition of particles with extreme energies. Large and sophisticated detectors are used to find events seen as showers starting in the Earth's atmosphere with recorded energies larger than 100 EeV. However, a Cosmic-Ray Ensemble (CRE) developing before reaching the Earth as a bunch of correlated particles may spread over larger areas and requires an extended set of detectors to be discovered. The Cosmic-Ray Extremely Distributed Observatory (CREDO) is a solution to find such phenomena. Even simple detectors measuring the particle arrival time only are useful in this approach, as they are sufficient both to provide candidate CRE events and to determine the direction from which they are arriving.

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van Dokkum, Pieter G. « Cosmic‐Ray Rejection by Laplacian Edge Detection ». Publications of the Astronomical Society of the Pacific 113, n^o 789 (novembre 2001) : 1420–27. http://dx.doi.org/10.1086/323894.

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Haungs, A., W. D. Apel, J. C. Arteaga, T. Asch, A. F. Badea, L. Bähren, K. Bekk et al. « Cosmic Ray Air Shower Detection with LOPES ». Nuclear Physics B - Proceedings Supplements 175-176 (janvier 2008) : 227–32. http://dx.doi.org/10.1016/j.nuclphysbps.2007.11.003.

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KAPPES, ALEXANDER. « GAMMA-RAY BURST DETECTION WITH ICECUBE ». International Journal of Modern Physics D 18, n^o 10 (octobre 2009) : 1561–65. http://dx.doi.org/10.1142/s0218271809015473.

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With their narrow emission window gamma-ray bursts (GRBs) are among the most promising objects for the first identification of high-energy cosmic neutrinos. If a considerable fraction of the ultra-high energy cosmic rays is indeed produced in GRBs, IceCube, which is now more than half-way completed, should be able to detect the associated neutrinos in the next few years. Furthermore, optical follow-up observations of neutrino multiplets will enhance IceCube's sensitivity to choked GRBs which do not produce a gamma-ray signal.

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ARDOUIN, D., A. BELLETOILE, D. CHARRIER, R. DALLIER, L. DENIS, P. ESCHSTRUTH, T. GOUSSET et al. « CODALEMA : A COSMIC RAY AIR SHOWER RADIO DETECTION EXPERIMENT ». International Journal of Modern Physics A 21, supp01 (juillet 2006) : 192–96. http://dx.doi.org/10.1142/s0217751x0603360x.

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The CODALEMA experimental device currently detects and characterizes the radio contribution of cosmic ray air showers : arrival directions and electric field topologies of radio transient signals associated to cosmic rays are extracted from the antenna signals. The measured rate, about 1 event per day, corresponds to an energy threshold around 5.1016eV. These results allow to determine the perspectives offered by the present experimental design for radiodetection of Ultra High Energy Cosmic Rays at a larger scale.

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Anderson, Rachel E., et Karl D. Gordon. « Optimal Cosmic-Ray Detection for Nondestructive Read Ramps ». Publications of the Astronomical Society of the Pacific 123, n^o 908 (octobre 2011) : 1237–48. http://dx.doi.org/10.1086/662593.

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Filonenko, A. D. « Superhigh-energy cosmic ray detection using shower radioemission ». Physics-Uspekhi 45, n^o 4 (30 avril 2002) : 403–32. http://dx.doi.org/10.1070/pu2002v045n04abeh000850.

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Buis, E. J., E. J. J. Doppenberg, R. A. Nieuwland et P. M. Toet. « Fibre laser hydrophones for cosmic ray particle detection ». Journal of Instrumentation 9, n^o 03 (27 mars 2014) : C03051. http://dx.doi.org/10.1088/1748-0221/9/03/c03051.

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