CASPAR 2013 Cosmic-rays Acceleration, Sources and Propagation: A Rendez-vous

10 Sept 2013, 08:00 → 19 Sept 2013, 18:00 Europe/Berlin

Building 61, Lecture Hall (DESY Hamburg)

Carmelo Evoli (II. Institut für Theoretische Physik, Universität Hamburg), Dieter Horns (Univ. Hamburg), Günter Sigl (Hamburg University), Peter Schiffer (Hamburg University)

Main topics of the workshop: Sources of Galactic and Extra-galactic cosmic rays Acceleration of cosmic rays Propagation of cosmic rays Gamma-ray astronomy Cosmic ray anisotropy: observations and interpretation Models of the Galactic and InterGalactic magnetic field Indirect Dark Matter searches Observations of the Extragalactic Background Light Invited speakers include: Denise Boncioli (INFN-LNGS) Torsten Enßlin (MPA) Andrea Ferrara (Scuola Normale Superiore) Stefano Gabici (APC) Hyesung Kang (Pusan University) Alex Lazarian (University of Wisconsin) Martin Lemoine (IAP) Andrii Neronov (ISDC) Angela Olinto (Kavli Institute) Martin Pohl (DESY) Dongsu Ryu (Chungnam University) Pierre Salati (LAPTh) Reinhard Schlickeiser (Universität Bochum) Andrew W. Strong (MPI) Diego F. Torres (Institute of Space Sciences) Piero Ullio (SISSA) Eli Waxman (Weizmann Institute) Huirong Yan (Peking University)

Agenda Agenda_CASPAR.pdf

Download the poster CASPAR2013-Workshop-Poster.pdf

Tuesday, 10 September

08:45 → 09:00 Welcome Speech

Speaker: Dr Carmelo Evoli (II. Institut für Theoretische Physik, Universität Hamburg)

Slides WelcomeSpeech.pdf

09:00 → 10:00 Galactic Cosmic Rays with H.E.S.S.

Speaker: Kathrin Egberts (Leopold-Franzens-Universität, Innsbruck, Austria)

Slides CASPAR2013_KEgberts.pdf

10:00 → 11:00 Results from AMS-02

Speaker: Iris Gebauer (Karlsruhe Institute of Technology, Karlsruhe, Germany)

Slides CASPAR2013_IGebauer.pdf

11:00 → 11:30 coffee break

11:30 → 12:30 Modeling of Galactic Cosmic Ray propagation in our Galaxy in light of recent AMS results

Speaker: Daniele Gaggero (SISSA, Trieste, Italy)

Slides CASPAR2013_DGaggero.pdf

14:30 → 15:00 coffee break

15:00 → 17:00 discussion session

Wednesday, 11 September

09:00 → 10:00 Sources of galactic cosmic rays

Speaker: Martin Pohl (DESY, Zeuthen, Germany)

Slides CASPAR_2013_MPohl.pdf

10:00 → 11:00 Galactic cosmic-ray & gamma-ray sources

In this talk I will make a few comments on three classes of sources: supernova remnants, pulsar-wind nebulae, and gamma-ray binaries. In the first part, on SNRs, I will comment on the recent detection of hadronic gamma-rays and prospects for future population analysis. Regarding PWNe i will focus on young TeV emitting systems, from the point of view of time-dependent modeling of the multiwavelength emission. Finally, on gamma-ray binaries, I will present the recent detection of long-term variability of gamma-rays and their possible relation to stellar cycles.

Speaker: Diego F. Torres (IEEC-CSIC, Barcelona, Spain)

Slides CASPAR_2013_DTorres.pdf

11:00 → 11:30 coffee break

11:30 → 12:30 Origin of galactic cosmic rays: the role of gamma-ray observations

Speaker: Stefano Gabici (APC, Paris, France)

14:30 → 15:00 coffee break

15:00 → 16:00 Anisotropic Cosmic Ray Diffusion and its Implications for Gamma-Ray Astronomy

Speaker: Dmitri Semikoz (AstroParticle and Cosmology (APC), Paris, France)

Slides CASPAR_2013_DSemikoz.pdf

16:00 → 17:00 discussion session

Thursday, 12 September

09:00 → 10:00 Cosmic ray transport in the interstellar medium

Speaker: Reinhard Schlickeiser (Universität Bochum, Bochum, Germany)

Slides CASPAR_2013_RSchlickeiser.pdf

10:00 → 11:00 Acceleration of cosmic rays in shocks and reconnection sites

I shall review the advances of our understanding of the First order Fermi acceleration of particles in shocks and sites of magnetic reconnection. I shall discuss how magnetic field generation in the shock precursor allows to accelerate cosmic rays to higher energies and how cosmic ray superdiffusion changes the accepted acceleration picture. I shall also discuss the process of fast reconnection of turbulent magnetic field and how this process provides efficient cosmic ray acceleration.

Speaker: Alex Lazarian (University of Wisconsin, USA)

Slides CASPAR_2013_ALazarian.pdf

11:00 → 11:30 coffee break

11:30 → 12:30 Particle transport and acceleration in turbulence

Speaker: Huirong Yan (Peking University, Beijing, China)

Slides CASPAR_2013_HYan.pdf

14:30 → 14:45 Aperitif

Speaker: Mr Andrey Saveliev (University of Hamburg)

Slides Saveliev_Hamburg.pdf

14:45 → 15:45 Localisation of cosmic ray sources via extended gamma and neutrino emission around them

Speaker: Andrii Neronov (ISDC Data Centre for Astrophysics, Geneva, Switzerland)

Slides CASPAR_2013_ANeronov.pdf

15:45 → 16:10 coffee break

16:10 → 17:00 discussion session

Friday, 13 September

09:00 → 10:00 Cosmic ray propagation and the generalized central limit theorem

It is amazing to realize that in the current description of Galactic propagation of cosmic rays (CR), sources are not point-like, at least for primary species like protons and helium nuclei. Considering that sources as localized in space and time is more realistic, but leads to puzzling results. Actually, in the Myriad model, the Galactic variance of, say, the proton flux at the Earth is infinite. Several suggestions have been made to cure this problem. One approach is to consider known local supernova remnants (SNR) and to treat the external sources as a continuous jelly. The proton and helium anomalies observed by PAMELA and CREAM can then be explained in that framework. It is also possible to go one step further and to solve the infinite variance problem of the Myriad model by making use of the generalized central limit theorem. I will show that the probability distribution function of the flux does exist in spite of an infinite variance. It follows a stable law with heavy tail well-known by financial analysts. The probability that the PAMELA and CREAM anomalies are sourced by local SNR can then be calculated.

Speaker: Pierre Salati (LAPTh, Annecy, France)

Slides CASPAR_2013_PSalati.ppt

10:00 → 11:00 Search for Dark Matter in the Galaxy

Speaker: Gabrijela Zaharijas (ICTP, Trieste, Italy)

Slides CASPAR_2013_GZaharijas.pdf

11:00 → 11:30 coffee break

11:30 → 12:30 Complementaries in indirect dark matter searches

Speaker: Piero Ullio (SISSA, Trieste, Italy)

Slides CASPAR_2013_PUllio.pdf

14:30 → 15:30 Dark matter searches in charged cosmic rays? Really?

Speaker: Philipp Mertsch (Stanford University)

Slides CASPAR2013_Mertsch.pdf

15:30 → 16:00 coffee break

16:00 → 17:00 discussion session

Monday, 16 September

09:00 → 09:15 Welcome Speech

Speaker: Günter Sigl (Hamburg University)

Slides WelcomeSpeech.pdf

09:15 → 10:15 New developments in our understanding of the origin of CRs

Speaker: Eli Waxman (Weizmann Institute of Science, Rehovot, Israel)

Slides CASPAR_2013_EWaxman.pptx

10:15 → 11:15 PeV Cosmic Rays measured by IceCube/IceTop

We report on the high-resolution measurements of cosmic ray spectrum and mass composition from the knee region up to 1 EeV based on one year of data collected with IceCube/IceTop. Complementary to the PeV neutrinos, IceCube measures extensive air showers of PeV cosmic rays on the surface with the IceTop array and the penetrating high energy muon bundles with the matrix of detectors in deep ice. The measured spectrum can not be explained by a simple power law beyond the knee, which confirm the other recent measurements (GAMMA, Tunka, Kascade-Grande). We observe a prominent hardening above 18 +/- 2 PeV followed by a sharp steepening beyond 130 +/- 30 PeV. In this egergy region, the composition gets heavier as indicated by the steady increase in the measured mean logarithmic mass lnA. The change in shape and amplitude of anisotropy observed by IceCube/IceTop in the arrival direction distributions of PeV cosmic rays will also be discussed. We will present a model independent analysis of the recent cosmic ray measurements driven by the combined data from satelite, balloon and air shower experiments. We find that at least 3 different source populations needed to describe the observed spectral shape and the mass composition from 200 GeV up to 200 EeV.

Speaker: Serap Tilav (University of Delaware, US)

Slides CASPAR_2013_STilav.pdf

11:15 → 11:45 coffee break

11:45 → 12:45 An almost perfect Universe - results from the Planck mission

The Planck satellite has mapped the cosmic microwave background (CMB) with unprecedented precision. An accurate determination of many cosmological parameters was possible and a number of early Universe scenarios could be constrained. The Planck mission, its main scientific results, and the anomalies seen in the CMB sky will be discussed in this talk. The impact of Galactic cosmic rays on the mission will also be shown.

Speaker: Torsten Enßlin (MPA, Garching, Germany)

Slides CASPAR_2013_TEnsslin.pdf

14:30 → 15:30 Neutrino astronomy with IceCube

Speaker: Juan Antonio Aguilar Sánchez (Université de Genève, Geneva, Switzerland)

Slides CASPAR_2013_JAguilar.pdf

15:30 → 16:00 coffee break

16:00 → 17:00 Recents results from the Pierre Auger Observatory

Speaker: Hans Dembinski (Karlsruher Institut für Technologie, Karlsruhe, Germany)

Slides CASPAR_2013_HDembinski.pdf

Tuesday, 17 September

09:00 → 10:00 Galactic Magnetic Field and Cosmic Rays

Speaker: Glennys Farrar (NYU, New York City, US)

Slides CASPAR_2013_GFarrar.pdf CASPAR_2013_GFarrar.ppt

10:00 → 11:00 Intergalactic Magnetic Field and Propagation of Ultra-High-Energy Cosmic Rays

Magnetic fields appear to be ubiquitous in astrophysical environments. The existence of magnetic fields in the large-scale structure (LSS) of the universe has been established through observations of Faraday rotation and synchrotron emission, as well as through recent gamma-ray observations, although their nature and origin remain controversial and largely unknown. In this talk, we first briefly review recent developments in our understanding of the intergalactic magnetic field (IGMF) and introduce a plausible model for it. We then describe how the IGMF affects the propagation of ultra-high-energy cosmic rays (UHECRs) that originate from extragalactic sources within the local universe. To this end, we set up hypothetical sources of UHECRs and virtual observers in the cosmic web magnetized with our model IGMF, and follow the trajectories of UHECRs in the intergalactic space. With our model IGMF, the paths of UHE protons and irons are deflected on average by about 15 and 70 degrees, respectively. But the IGMF at the same time contains UHECRs and the correlation between the observed UHECRs and the LSS is preserved. For instance, again with our model IGMF, the separation angles between the arrival directions and the nearest reference objects on the LSS are on average about 3.5 and 6 degrees for UHE protons and irons, respectively, which are much smaller than the defection angles. We discuss implications of our findings for correlation studies in current UHECR experiments.

Speaker: Dongsu Ryu (Chungnam National University, Korea)

Slides CASPAR_2013_DRyu.pdf

11:00 → 11:30 coffee break

11:30 → 12:30 Diffusive shock acceleration at cosmological shock waves

Cosmological shock waves result from supersonic flow motions induced by hierarchical clustering of nonlinear structures in the universe. These collisionless shocks are thought to accelerate high-energy cosmic rays (CRs) via diffusive shock acceleration (DSA) mechanism. In this talk, we will review 1) the properties and energetics of shocks formed in cosmological structure formation simulations, 2) recent studies on how magnetic field amplification by CR streaming instabilities and Alfvenic drift may affect the DSA efficiency at strong shocks, 3) importance of re-acceleration of CRs at weak cosmological shocks and its implications on radio relics, 4) the nature and roles of infall shocks that form mostly in cluster outskirts, and 5) the possibility of the acceleration of ultra-high energy CRs at cluster accretion shocks.

Speaker: Hyesung Kang (Pusan National University, Korea)

Slides CASPAR_2013_HKang.pdf

14:30 → 15:30 Acceleration to ultra-high energies

Speaker: Martin Lemoine (IAP, Paris, France)

Slides CASPAR_2013_MLemoine.pdf

15:30 → 16:00 coffee break

16:00 → 17:00 discussion session

Wednesday, 18 September

09:00 → 10:00 Where did UHECRs come from?

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 by heavier nuclei at the highest energies) or the hadronic interactions at 100 TeV are not a standard extrapolation of LHC interaction energies. The basic question in the field remains unanswered: what generates such extremely energetic particles that reach above 10^20 eV (100 EeV)?. Where do they come from? How do they reach these energies? What are they (protons or heavier nuclei?)? How do they interact on their way to Earth and with the Earth’s atmosphere? To answer these questions larger statistics at the highest energies is necessary. Space-based observatories can significantly improve the exposure to these extremely energetic particles. The first step to answer these questions is to place a wide field UV telescope at the International State Station to monitor the Earth’s atmosphere from above. This is the goal of the JEM-EUSO mission, which stands for Extreme Universe Space Observatory (EUSO) at the Japanese Experiment Module (JEM).

Speaker: Angela Olinto (KICP, Chicago, USA)

Slides CASPAR_2013_AOlinto.pdf

10:00 → 11:00 Extragalactic propagation of UHECRs

Speaker: Denise Boncioli (INFN-LNGS, L’Aquila, Italy)

Slides CASPAR_2013_DBoncioli.pdf

11:00 → 11:30 coffee break

11:30 → 12:30 Propagation and interpretation of ultra-high energy cosmic rays using CRPropa

Speaker: Daniel Kuempel (RWTH Aachen University, Germany)

Slides CASPAR_2013_DKuempel.pdf

14:30 → 15:30 The view on cosmic rays in galaxy clusters from numerical simulations and observations

The intra cluster medium is a dynamically active environment, in which dissipation of large motions and acceleration of cosmic rays are likely ubiquitous processes. I will review the present theoretical uncertainties and firm conclusions on cosmic rays in the intra cluster medium, coming from broad-band observations and the updated cosmological numerical modelling of these systems.

Speaker: Franco Vazza (Hamburger Sternwarte, Hamburg, Germany)

Slides http://prezi.com/hido40iadguc/?utm_campaign=share&utm_medium=copy&rc=ex0share

15:30 → 16:00 coffee break

16:00 → 17:00 discussion session

Thursday, 19 September

09:00 → 10:00 The Near Infrared Background: puzzles and promises

I will review the present status of the understanding of the Near Infrared Background light. In particular I will focus on recent experimental and theoretical progresses that hint at the possibility that a fraction of this cosmic light traces the most distant galaxies and, even more likely, the first black holes, thus opening an exciting pathway to study the early Universe.

Speaker: Andrea Ferrara (SNS, Pisa, Italy)

Slides CASPAR_2013_AFerrara.pdf

10:00 → 11:00 Extragalactic Background Light: a Review

I will provide a review of our knowledge of the Extragalactic Background Light (EBL): 1- measurements of intensity across the electromagnetic spectrum; 2- measurements of fluctuations; 3- what do all this tell us, link to models. I will highlight the CIB (Cosmic Infrared Background).

Speaker: Hervé Dole (Institut d'Astrophysique Spatiale, Orsay)

Slides CASPAR_2013_HDole.pdf

11:00 → 11:30 coffee break

11:30 → 12:30 Extragalactic messengers: some open questions

Speaker: Michael Kachelriess (NTNU Institutt for fysikk, Trondheim, Norway)

Slides CASPAR_2013_MKachelriess.pdf

15:30 → 16:00 coffee break

16:00 → 17:00 discussion session