Conveners
Cosmic Rays
- Elena Amato (INAF - Osservatorio Astrofisico di Arcetri)
Cosmic Rays: Cosmic Rays
- Elena Amato (INAF - Osservatorio Astrofisico di Arcetri)
Cosmic Rays: Cosmic Rays
- Veronica Bindi (University of Hawai'i at Manoa (US))
Cosmic Rays: Cosmic Rays
- Veronica Bindi (University of Hawai'i at Manoa (US))
Cosmic Rays: Cosmic Rays
- Kumiko Kotera (Institut d'Astrophysique de Paris)
Cosmic Rays: Cosmic Rays
- Kumiko Kotera (Institut d'Astrophysique de Paris)
Dr
Brian Reville
(Queen's University Belfast)
23/06/2014, 14:30
Cosmic Rays
Presentation
In recent years, our understanding of cosmic-ray acceleration at supernova shocks has advanced considerably. Observations of nearby SNR show clear evidence for magnetic field amplification, while theory and simulation has developed to the point where we can now investigate the plasma physics in these energetic environments self-consistently. I will review some of the recent developments in the...
Damiano Caprioli
(Princeton University)
23/06/2014, 14:55
Cosmic Rays
Presentation
Hybrid particle in cell simulations (with kinetic protons and fluid electrons) are providing us with unprecedented insights into the microphysics of collisionless shocks, also attesting to their ability to accelerate particles and to generate magnetic fields.
I present state-of-the-art 2D and 3D simulations of non-relativistic shocks, discussing under which conditions (shock strength and...
Gwenael Giacinti
(University of Oxford, Clarendon Laboratory)
23/06/2014, 15:20
Cosmic Rays
Presentation
The energy around which the transition from Galactic to extragalactic cosmic rays (CR) occurs is still unknown. Solving this major question would bring valuable clues about the nature and characteristics of Galactic and extragalactic CR sources, such as the maximum energy reachable by Galactic accelerators. The transition must lie between the knee (energy E ~ 4 PeV) and the ankle (E ~ 3 EeV)....
Paolo Bernardini
(Universita' del Salento - INFN)
23/06/2014, 15:45
Cosmic Rays
Presentation
The ARGO-YBJ detector layout, features and location at high altitude (the Cosmic Ray Observatory of Yangbajing in Tibet, China, at about 606 g/cm^2 of atmospheric depth), joined to the analog readout of the RPC (Resistive Plate Chamber) streamer signals, provide the opportunity to study, with unprecedented resolution and without saturation, the distribution of the charged particles of...
Martina Cardillo
(INAF - Osservatorio astrofisico di Arcetri)
23/06/2014, 16:30
Cosmic Rays
Presentation
One of the main open issues about the origin of Galactic CRs is the maximum energy that can be achieved by acceleration in Supernova Remnants.
In a rigidity dependent acceleration mechanism, protons are expected to reach a few PeV and heavier ions correspondingly higher energies.
A recent theory suggests that, in a core-collapse SNR expanding in its pre-supernova wind, magnetic field...
Satyendra Thoudam
(R)
23/06/2014, 16:48
Cosmic Rays
Recent measurement of cosmic rays by the ATIC, CREAM and PAMELA experiments have found that the energy spectrum in the TeV region is harder than at GeV energies. The origin of the hardening is not clearly understood. Suggested explanations include hardening in the cosmic-ray source spectrum, changes in the cosmic-ray propagation properties in the Galaxy and the effect of the nearby sources. In...
Daniele Gaggero
23/06/2014, 17:06
Cosmic Rays
Presentation
We present some results obtained with the anisotropic version of the CR propagation package DRAGON.
First we describe some quantitative test of the code in simple conditions for which the analytical solution of CR transport is known, both for a the case of a dominant parallel or perpendicular diffusion.
Then we show that, for the first time, we are able to reproduce the most important CR...
Giovanni Morlino
(G)
23/06/2014, 17:24
Cosmic Rays
Presentation
We present the theory of non-linear particle acceleration in collisionless shocks in the presence of atomic neutral material in the acceleration region. The main new aspect consists in accounting for charge exchange and ionization of neutral hydrogen, which profoundly change the structure of the shock. We also present the self-consistent calculation of the Balmer emission lines from the shock...
Giuseppe Di Bernardo
23/06/2014, 17:49
Cosmic Rays
Fairly poor knowledge is still present about the cosmic ray (CR) spectra at low energies, due to the distortion produced by the solar wind on the particle fluxes. A self-consistent galactic plus solar propagation model turns out necessary in order to correctly reproduce the CR nuclear and lepton spectra.
For that, a detailed transport description in the galaxy has been...
Marco Taoso
23/06/2014, 18:07
Cosmic Rays
Presentation
The observed radio sky at frequencies below few GHz is the sum of the isotropic extragalactic background and the Galactic emission. The latter includes the diffuse synchrotron radiation produced by cosmic-rays electrons spiraling in the Galactic magnetic field. Therefore radio maps are an useful tool to constrain the interstellar electrons spectrum and magnetic fields. We present a detailed...
Roberta Sparvoli
(University of Rome Tor Vergata)
24/06/2014, 14:30
Cosmic Rays
Presentation
In about 8 years of data taking in space, the experiment PAMELA has shown very interesting features in cosmic rays, namely in the fluxes of protons, heliums, electrons, that could have significant implications on the production, acceleration and propagation of cosmic rays in the galaxy. In addition, PAMELA measurements of cosmic antiproton and positron fluxes are setting strong constraints to...
Prof.
Eun-Suk Seo
(University of Maryland)
24/06/2014, 14:55
Cosmic Rays
Presentation
The balloon-borne Cosmic Ray Energetics And Mass (CREAM) experiment was flown for ~161 days in six flights over Antarctica. High energy cosmic-ray data were collected over a wide energy range from ~ 10^10 to > 10^14 eV at an average altitude of ~38.5 km with ~3.9 g/cm2 atmospheric overburden. Cosmic-ray elements from protons (Z = 1) to iron nuclei (Z = 26) are separated with excellent charge...
Prof.
Shoji Torii
(Waseda University)
24/06/2014, 15:20
Cosmic Rays
Presentation
The CALET space experiment, currently under development by Japan in collaboration with Italy and the United States,will measure the flux of Cosmic Ray electrons (and positrons) to 20 TeV, gamma rays to 10 TeV and nuclei with Z=1 to 40 up to 1,000 TeV during a five year mission. These measurements are essential to investigate possible nearby astrophysical
sources of high energy electrons,...
Valerio Vagelli
(KIT - Karlsruhe Institute of Technology (DE))
24/06/2014, 15:45
Cosmic Rays
The AMS-02 detector is a large acceptance cosmic ray detector operating on the International Space Station since May 2011.
About 40 billion events have been collected by the instrument in the first 30 months of data taking.
Among them, 10.5 million of electrons and positrons have been selected to measure the cosmic lepton energy spectrum at energies up to the TeV.
In this contribution we...
Mattia Di Mauro
(University of Turin and INFN Turin)
24/06/2014, 16:30
Cosmic Rays
Presentation
We perform a combined analysis of the recent AMS-02 data on electrons, positrons, electrons plus positrons and positron fraction, in a self-consistent framework where we realize a theoretical modeling of all the astrophysical components that can contribute to the observed fluxes in the whole energy range. The primary electron contribution is modeled through the sum of an average flux from...
Dario Grasso
(INFN)
24/06/2014, 16:45
Cosmic Rays
Presentation
We use the three-dimensional upgrade of the DRAGON code to model the electron and positron spectra measured by PAMELA and AMS-02.
Presently this is the only cosmic ray (CR) propagation package which allows to account for a realistic spiral arm distribution of CR source in the Galaxy. We find that, once the propagation models are tuned to reproduce the B/C and proton data the lepton data...
Marianne Lemoine-Goumard
(CNRS)
24/06/2014, 17:00
Cosmic Rays
Presentation
Supernova remnants (SNRs) are thought to be the primary sources of the bulk of Galactic cosmic-ray protons observed at Earth, up to the knee energy at ~3 PeV. Our understanding of CR acceleration in SNRs mainly relies on the so-called Diffusive Shock Acceleration theory which is commonly invoked to explain several observational (though, indirect) lines of evidence for efficient particle...
Prof.
Philip Von Doetinchem
(University of Hawaii at Manoa)
24/06/2014, 17:25
Cosmic Rays
Presentation
In recent years the interest in cosmic ray antideuteron measurements has increased due to detection potential of signals from a variety of dark matter, primordial black hole, or gravitino models. This talk will review the motivations and status of cosmic ray antideuteron searches and discuss future detection prospects.
Alberto Oliva
(Centro de Investigaciones Energ. Medioambientales y Tecn. - (ES)
24/06/2014, 17:50
Cosmic Rays
Presentation
AMS-02 is a high-energy particle physics experiment operating continuosly since May 2011 onboard of the International Space Station.
Given the wide acceptance, long exposure time and particle identification capabilities, AMS-02 is able to determine the cosmic rays (CRs)
chemical composition from charge $Z=1$ up to at least $Z=26$ in a kinetic energy range from GeV/n to few TeV/n.
Among the...
Nicola Mori
(Universita e INFN (IT))
24/06/2014, 18:05
Cosmic Rays
Presentation
PAMELA is a satellite-borne experiment, aimed at precision measurements of
the charged light component of the cosmic-ray spectrum. It consists of a
magnetic spectrometer, a time-of-flight system, an electromagnetic
calorimeter, an anticoincidence system and a neutron detector. Recently, the
PAMELA collaboration has finalized the measurement of the absolute fluxes of
boron and carbon and...
Philipp Mertsch
(KIPAC, Stanford University)
24/06/2014, 18:20
Cosmic Rays
Recently, the AMS-02 collaboration has presented data on cosmic ray protons, Helium, electrons and positrons as well as the boron-to-carbon ratio. We present the first consistent modelling of these data, paying particular attention to the contribution due to production and acceleration of secondary electrons and positrons in nearby supernova remnants. This process results in an additional,...
Eun-Joo Ahn
(F)
26/06/2014, 14:30
Cosmic Rays
Presentation
Cosmic rays have now been observed for over a century. The nature and origins of the ultra high energy cosmic rays are questions that have yet to be definitively answered. The southern Pierre Auger Observatory, located in Argentina, is currently the world's largest detector of ultra high energy cosmic rays. With unprecedented amount of data collected, it is shedding light to questions on the...
Kazumasa Kawata
26/06/2014, 14:55
Cosmic Rays
Presentation
The Telescope Array (TA) is the largest ultra-high-energy cosmic-ray (UHECR) detector in the northern hemisphere, which consists of 507 surface detector covering a total 700 km^2 and three fluorescence detector stations. The TA has been fully operating at Millard Country, Utah, USA, since 2008. In this presentation, we will discuss our recent results on the UHECR energy spectrum, mass...
Silvia Mollerach
26/06/2014, 15:20
Cosmic Rays
Presentation
The Pierre Auger Observatory has been in operation since January 2004, detecting
cosmic rays with energies from few 10 PeV to more than 100 EeV. We present the
results of anisotropy studies of the arrival directions at different angular
scales and energies using both the data recorded by the 1500 m grid array,
covering 3000 km^2 and fully efficient above 3 EeV, and the 750 m grid array,...
Dr
Martin Lemoine
(Institut d'Astrophysique de Paris)
26/06/2014, 15:35
Cosmic Rays
Presentation
The origin of the highest energy cosmic rays with energy >~ 10^{18}eV is a rather intricate puzzle, with a central question: how to accelerate particles to extreme energies ~10^{20}eV or more, and in which astrophysical source? Other questions arise as well, such as: are these cosmic rays protons or nuclei? Why is there no powerful source in the arrival directions of the highest energy cosmic...
Glennys Farrar
(NYU)
26/06/2014, 16:30
Cosmic Rays
Presentation
- A simple and well-motivated modification of QCD at ultrahigh energy naturally explains the observed Xmax distribution above 10^18 eV, with a purely protonic composition. This removes the need for a fine-tuned source composition and very hard injection spectrum as required if UHECRs have a mixed composition, and eliminates the need to postulate an additional population of extragalactic...
Markus Ahlers
26/06/2014, 16:45
Cosmic Rays
Presentation
The origin of ultra-high energy (UHE) cosmic rays (CRs) is an unsolved puzzle. Multi-messenger obervations in the form of gamma-rays and neutrinos can help to constrain the cosmic evolution and emission spectra of UHE CR candidate sources. I will discuss the production of cosmogenic gamma-ray and neutrino fluxes from the propagation of UHE CRs through the cosmic radiation background. These...
Fiorenza Donato
26/06/2014, 17:10
Cosmic Rays
Presentation
We evaluate the contribution to the high latitude gamma-ray emission in the GeV-TeV energy range as due to various AGN populations. We give an estimation of the unresolved energy spectrum and compare our results to the data collected by the Fermi-LAT. We also briefly discuss the relevant anisotropy in the IGRB. Finally, we give some hints to the possibility left to dark matter searches in the...
Angela Olinto
(The University of Chicago)
26/06/2014, 17:35
Cosmic Rays
Presentation
Thanks to giant extensive air-showers observatories, such as the Pierre Auger Observatory and the Telescope Array, we now know that the sources of ultrahigh energy cosmic rays (UHECRs) are extragalactic. We also know that either they interact with the CMB as predicted or they run out of energy at the same energy scale of the CMB interactions! Their composition is either surprising (dominated...
Stijn Buitink
(Radboud University Nijmegen)
26/06/2014, 18:00
Cosmic Rays
Presentation
It is generally believed that ultra-high-energy cosmic rays are produced in extragalactic sources like gamma-ray bursts or active galactic nuclei, while the lower energy cosmic rays come from our own Galaxy. At what energy the transition from Galactic to extragalactic origin takes place is still a mystery, but most models place it somewhere between $10^{17}$ and $10^{19}$ eV. With LOFAR we can...
Prof.
Jörg Hörandel
(Radboud University Nijmegen/Nikhef)
26/06/2014, 18:15
Cosmic Rays
Presentation
High-energy cosmic rays impinging onto the atmosphere of the Earth initiate cascades of secondary particles: extensive air showers. The electrons and positrons in air showers interact with the geomagnetic field and emit radiation, which we record in the tens-of-MHz regime. Radio emission from air showers is measured with the Auger Engineering Radio Array (AERA) at the Pierre Auger Observatory...
