International School of Cosmic Ray Astrophysics

14th  Course: "Neutrinos and Explosive Events in the Universe"

A NATO Advanced Study Institute

 2-13 July 2004
Ettore Majorana Centre
Erice, Sicily, Italy


Contributed Presentations

M. R. Moser

Physikalisches Institut, University of Bern, CH-3012 Bern, Switzerland

Nuclear and pion related -rays provide important probes of the spectra of protons accelerated in solar ares. Nuclear -ray lines probe the proton spectrum only up to 40 MeV, while -rays from pion decays are only observed in the most intense ares. In addition, any spectral break in the proton spectrum is likely to lie below the pion production threshold. Neutrons produced at the solar surface over a wide range of energies may provide important information from the critical 50{300 MeV regime, complementing -ray observations. Since the 2.223 MeV neutron capture line is a limited measure of neutron production, the proton spectrum must be deduced from direct neutron measurements.  As an illustration of ground-based solar neutron observation, the concept and results of the world-wide solar neutron telescope network set up during the last decade by the Solar{Terrestrial Environment Laboratory of the University of Nagoya in Japan will bem presented.

After discussing the limitations of ground-based neutron detection the paper will then focus on direct solar neutron observation from space. The concept and performance of two detectors currently being developed under the leadership of the University of Alabama in Huntsville and the University of New Hampshire in Durham will be demonstrated.

Topic: Spin-Dependent Direct Dark Matter Search
I.V.Titkova, V.A.Bednyakov

JINR, Dubna, Russia

The Weakly Interacting Massive Particle (WIMP) is the main candidate for the relic dark matter. A set of exclusion curves currently obtained for cross sections of the spin-dependent WIMP-proton and WIMP-neutron interaction is given. A two-orders-of-magnitude improvement of the sensitivity of the dark matter experiments is needed to reach the SUSY predictions for relic neutralinos. it is noted that new experiments with the high-spin isotope Ge(73) can yield a new important constraint on the neutralino-neutron effective coupling and the SUSY parameter space.

Topic: Open Star Clusters and the Milky Way's Spiral Arm Dynamics
Smadar Levi and Nir J Shaviv

The Hebrew University of Jerusalem

We map and study the dynamics of the MilkyWay's spiral arms in our vicinity using the birth place of open clusters. We find that the data is best fitted with two pattern speeds. We place limits on the speeds, the geometrical parameters, and attempt to study the amplitude of the spiral density perturbation.

Topic: Results from the Antarctic Muon And Neutrino Detector Array (Amanda)
Andrea Silvestri for the Amanda Collaboration

Department of Physics and Astronomy

University of California, Irvine, CA 92697, USA

We present new results from the Amanda-II high energy neutrino telescope, located at the South Pole in Antarctica. Amanda-II is a multipurpose neutrino telescope with a broad physics and astrophysics scope. We anticipate presenting results from the first two years of Amanda-II, which began operation in February, 2000. The sensitivity of the detector was calibrated from the measurement of the atmospheric muon-neutrino rate. The talk will summarize the results from searches for a variety of sources of ultra-high energy neutrinos: TeV-PeV diffuse sources by measuring either muon tracks or cascades, neutrinos in excess of PeV by searching for muons traveling the downgoing direction, generic point sources, sources correlated with GRBs and exotic particles like WIMPs and magnetic monopoles.

Topic: Status and First Results of ANtarctic Impulse Transient Antenna (ANITA)
Andrea Silvestri for the ANITA Collaboration

Department of Physics and Astronomy

University of California, Irvine, CA 92697, USA

We describe a new method to search for neutrinos at the energy frontier, based on the observation of short duration radio pulses that are emitted from a neutrino initiated cascade. The primary objective of the Anita mission is to measure the flux of Greisen-Zatsepin-Kuzmin (GZK) neutrinos, and search for neutrinos expected from AGN models. We present first-look results obtained from the successful launch of a 2-antenna prototype instrument (called Anita-Lite) that circled Antarctica for 18 days during the 03/04 Antarctic campaign, and show preliminary results from attenuation length studies of electromagnetic waves at radio frequencies in Antarctic Ice.

Topic: Monte Carlo simulations and semianalytical parameterisations of the atmospheric muon flux
B.Mitrica1, I.M.Brancus1, G.Toma1, J.Wentz1;2, H.Rebel2;3, A.Bercuci1, C.Aiftimiei1

1 IFIN-HH, RO-76900 Bucharest, POB MG-6, Romania

2 Forschungszentrum Karlsruhe, POB 3640, 76021 Karlsruhe, Germany

3 University of Heidelberg, 69120 Heidelberg, Germany

Contact e-mail: bogdan.mitrica@i

The atmospheric muon ux have been simulated using the CORSIKA code for two different geographical positions (Bucharest: 44°N; 26°E and Hiroshima: 34°N; 132°E). The simulations have been done for different angles of incidence between 0° and 70°. The comparison between the simulations and the experiment have been done using the measurements of the muon charge ratio with the WILLI detector in Bucharest. The results of the Monte Carlo simulations of the muon ux for the geographical positions of Hiroshima and Bucharest are compared with the semi-analytical formulae of Judge and Nash, and of Gaisser for different angles of incidence between 0° and 70° and with experimental results of the Bess experiment (vertical incidence). Various sensitivities of the approach of Judge and Nash, in particular to variations of the pion and kaon production spectra have been studied.

Topic: Observation of very high energy Gamma Rays from the Remnant of SN 1006 with HEGRA CT1.
 Vincenzo Vitale for the HEGRA Collaboration

Max Planck Institute for Physics, Föringer Ring 6, 80805 Munich, Germany

 The Galactic Cosmic Rays (GCRs, those Cosmic Rays with intermediate energy between 10s of GeV and 100s of TeV per unit of charge) are known from more then nine decades. The Super Nova Remnants (SNRs) are the most popular GCRs candidate accelerators. But up to now we miss an unquestioned experimental proof of this theory.

Therefore the HEGRA collaboration observed the SN 1006 shell–type remnant, in an up to now unexplored energy region above 15-20 TeV.

An excess of multi-TeV gamma rays is observed from the North East remnant cap. Only large zenith angle (ZA) observations are possible from the telescope site. The energy threshold is ≈ 18 TeV. The observations, data analysis and results will be discussed.

Topic: Ultrahigh-Energy Cosmic Rays by Yakutsk EAS Array
 A. Mikhailov

Yu.G. Shafer Institute of Cosmophysical Research and Aeronomy,

31 Lenin Ave., 677891 Yakutsk, Russia

Extensive air showers (EASs) of energy above 1018 eV observed from 1974 to 2003 on the Yakutsk EAS array are analyzed. Experimental data at the energy E ~ 1019 eV show the possible presence of anisotropy from the Galaxy plane side. The arrival directions of EAS are found to correlate with pulsars located in the directions of the Orion Arm of the Galaxy. The mass composition of ultrahigh-energy cosmic rays has been estimated. The origin of cosmic rays is discussed.

Topic: Radial distribution of GRBs in host galaxies.
 Kosenko, D.I.(1,2); Bartunov, O.S.(1); Blinnikov, S.I(1,2); Postnov,  K.A.(1)

1: Sternberg Astronomical Insitute (SAI)

2: Institute for Theoretical and Experimental Physics (ITEP)

We investigate correlation of GRBs radial distribution in host galaxies with distributions of other phenomena in galaxies (such as supernovae, dark matter, X-ray binary systems). Various statistical methods are used to test the hypothesis that GRBs and some of the other objects distributed similarly. Errors in localization of GRBs host galaxies and rather different structure of distant galaxies make it difficult to give a straight answer the question which type of nearby objects has the similar radial profile though.


Topic: Modeling of cosmic ray acceleration at relativistic shocks
 Jacek Niemiec1 and Michal Ostrowski2

1. Institute of Nuclear Physics PAN, Krakow, Poland

2. Astronomical Observatory, Jagiellonian University,Krakow, Poland

First-order Fermi acceleration processes at relativistic shock waves are investigated with the method of Monte Carlo simulations. The simulations are based on numerical integration of particle equations of motion in a turbulent magnetic field near the shock. In comparison to earlier studies a few 'realistic' features of the magnetic field structure are included. The field consists of a mean field component inclined at some angle to the shock normal and finite-amplitude perturbations imposed upon it. The perturbations are assumed to be static in the local plasma rest frame.  We apply an analytic model for the turbulence with a flat or Kolmogorov spectrum within a finite (wide) wave vector range. The downstream field structure is derived from the upstream one from the hydrodynamical shock jump conditions, so that the magnetic field is continous across the shock.  We present and discuss particle spectra and angular distributions obtained at mildly relativistic sub- and superluminal shocks.  We show that particle spectra diverge from a simple power-law, an exact shape of the spectrum depends on both an amplitude of the magnetic field perturbations and the wave power spectrum considered. We also present results concerning parallel shocks. In this case the finite-amplitude magnetic field perturbations lead to locally oblique field configurations at the shock and the respective magnetic field compressions. It results in modification of the particle acceleration process introducing some features observed in oblique shocks, like particle reflections from the shock. We demonstrate a non-monotonic variation of the accelerated particle spectral index with the turbulence amplitude. At the end, a few astrophysical consequences of the results we obtained are mentioned.

Title: Detecting TeV black holes with cosmic ray air shower
Authors: Eun-Joo Ahn, Maximo Ave, Marco Cavaglia, Angela Olinto


- Department of Astronomy and Astrophysics, University of Chicago (Eun-Joo Ahn, Angela Olinto)
- Kavli Institute for Cosmological Physics, University of Chicago (Maximo Ave, Angela Olinto)
- Department of Physics and Astronomy , University of Mississippi (Marco Cavaglia)
- Enrico Fermi Institute, University of Chicago (Angela Olinto)


If large extra dimensions exist, microscopic black holes can be created in the atmosphere by the collisions of ultrahigh energy cosmic rays with atmospheric nuclei. Air showers generated by these black holes could be observed at cosmic ray observatories such as the Pierre Auger Observatory.  The decay of these objects are significantly different from other standard model processes. We present a study of how to differentiate extensive air showers generated by TeV gravity effects from those generated by standard model interactions.

Topic: On Dynamics of Relativistic Shock Waves With Losses in Gamma-Ray Burst Sources
Lecturer: K.A. Martianov1, E.V. Derishev2 , Vl.V. Kocharovsky2

1Nizhny Novgorod State University

2Institute of Applied Physics

We consider expansion of ultra-relativistic spherical blast wave into a cold uniform medium. Such shocks can be produced by a strong explosion, in particular, in the sources of gamma-ray bursts, where the Lorentz factor of shock wave must exceed several hundred. Therefore, the medium behind the shock front is extremely hot and essentially dissipative.

We discuss two models. In the first model, we assume the energy losses to be concentrated close to the shock. In this case, the dissipative shock wave is described by three parameters: the fractions of energy, momentum and particle fluxes lost at the shock front. The matter downstream the shock is assumed to be non-dissipative and, for sufficiently large values of the Lorentz factor, has the equation of state of photon gas. The jump conditions for the pressure, energy density and velocity of the medium at the dissipative shock front are derived. Another model assumes the shock front to be non-dissipative while the losses are distributed in the medium behind the shock.

We obtain a self-similar solution for all the parameters of the shocked fluid that corresponds to a power-law time dependence of the Lorentz factor of the shock front. Our solution is based on hydrodynamical approach that is reasonable for astrophysical applications, though it can break for small fraction of the most energetic particles. The self-similar solution is exactly valid only for special initial conditions, however a solution in an arbitrary case asymptotically approaches the self-similar one. It is shown that there are two regions in the parameter space where the solutions are qualitatively different, depending on the magnitude of losses. In the case of small losses, the profile of the bulk Lorenz factor behind the shock front is invariable, but the time dependence of the shock-front Lorenz factor is changing. On the contrary, large losses lead to the universal time dependence of the Lorenz factor at the shock front and different profiles of the bulk Lorenz factor behind it. An expanding spherical cavity interior to the shock front with a temperature singularity at its edge is a common feature of the self-similar solutions in the second region of parameter space.

Topic: Neutrinos produced by heavy nuclei injected by the pulsars in massive binaries
Lecturers: Marek
Bartosik & W lodek Bednarek

Department of Experimental Physics, University of L´od´z, POLAND

We consider propagation of relativistic heavy nuclei injected by a young pulsar into the radiation field of a massive companion inside the binary system. For close enough systems, the nuclei suffer multiple photodesintegrations in collisions with thermal photons coming from the massive star injecting neutrons and protons. Some of these neutrons, protons and remnants of nuclei collide with the massive star producing high energy neutrinos. We calculate the spectra of escaping neutrinos and their expected fluxes as a function of the viewing angle applying as an example the parameters of the Cyg X-3 system. The effects of propagation of charged particles in the magnetic field of the massive companion are taken into account.

Topic: Direct Measurement of Cosmic-Ray Energy Loss in the Heliosphere Using Electron-Capture Decay Isotopes
Lecturers: L.M. Scott1, A.J. Davis2, M.E. Wiedenbeck4, W.R. Binns1, A.C. Cummings2, J.S. George2, P.L. Hink1,6, M.H. Israel1, R.A. Leske2, R.A. Mewaldt2, S.M. Niebur1,5, T.T. von Rosenvinge3, and N.E. Yanasak2,7

1Department of Physics and McDonnell Center for the Space Sciences, Washington University, St. Louis, MO 63130

2Space Radiation Laboratory, California Institute of Technology, Pasadena, CA 91125

3NASA Goddard Space Flight Center, Code 661, Greenbelt, MD 20771

4Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109

5Current address: Code SE, NASA Headquarters, Washington, DC 20546

6Current address: Burle Industries, Lancaster, PA 17601

8Current address: Dept. of Psychology, University of Georgia, Athens, GA 30602

We report a direct measurement of the value of the solar modulation parameter ö. This parameter characterizes the energy loss of cosmic rays as they diffuse in the interplanetary magnetic field embedded in the expanding solar wind. Using the Cosmic Ray Isotope Spectrometer (CRIS) on NASA’s Advanced Composition Explorer (ACE), we report on the energy-dependence of the electron-capture decay of the secondary isotopes 49V and 51Cr to 49Ti and 51V, respectively. At the highest energies observed by CRIS, where electron attachment is unlikely, 49V and 51Cr are essentially stable; at lower energies the timescale for electron attachment is comparable to that for fragmentation or escape from the Galaxy and substantial decay does occur. Comparing the energy-dependence of the daughter/parent ratios 49Ti/49V and 51V/51Cr during periods of solar minimum and maximum conditions demonstrates that ö is about 350 - 400 MV during solar minimum and about 800 - 1100 MV at solar maximum. Absolute values of ö inferred from these electron-capture-isotope data are in good agreement with the values inferred from comparison of the observed elemental energy spectra with models of cosmic-ray propagation in the Galaxy and heliosphere.

Topic: The efficiency of using accretion power of spinning black holes
Lecturers: Ioana Dutan, Peter L. Biermann

Max Planck Institute for Radioastronomy, Bonn, Germany and University of Bucharest, Romania


The efficiency of a rapidly spinning black hole to turn accretion power into observable power can attain 30 percent for the photon emission from the disk, as is well known, following the work of Thorne. Also, magnetic field can extract energy from the rotation of the black hole via the Blandford and Znajek process. Many accretion disks are now understood to be underluminous, while still putting large amounts of energy into the jet. Here we ask whether the energy put into powering the ubiquitous relativistic jet can reach also 30 percent of the accretion power or even more. We present some arguments for enhancing the efficiency of the disk surrounding a Kerr black hole above the value predicted by the Page and Thorne model.  They noted that magnetic field attached to the disk may reach into the horizon, producing a torque on the hole. The rotating energy and the angular momentum of a black hole can be extracted by the surrounding magnetic field. This idea has been rejuvenated by recent work.

Topic: The propagation of Ultra High Energy Cosmic Rays in the Galaxy magnetic fields
Lecturers: Andrii Elyiv, Bohdan Hnatyk

Astronomical Observatory of Taras Shevchenko Kyiv National University

We investigate the propagation of Ultra High Energy Cosmic Rays (UHECRs) in the magnetic field of Galaxy. Two models of galactic magnetic field, paired and unpaired, have been considered. The maps of angular dependence of deviation of UHECR arrival directions for both models of magnetic field have been constructed. Correction of observable UHECR arrival direction was made with taking into account magnetic field of Galaxy. In case of unpaired magnetic field model a near-equatorial zone of avoidance of cosmic rays is revealed. We investigate also the possibility of magnetic lensing of UHECR stream by magnetic fields of galaxies.


Topic: Relativistic shocks in external layers of Hypernova stars
Lecturers: Volodya Marchenko, Bohdan Hnatyk

Astronomical Observatory of Taras Shevchenko Kyiv National University

The hydrodynamics and observational signatures of relativistic shock breakout at the surface of Hypernova star are investigated. The characteristics of hydrodynamically accelerated external layers of star (energy spectrum of accelerated particles etc.) are estimated and an interaction of accelerated particles with the circumstellar medium is considered. Particularly we analyze a gamma ray flash as a result of inelastic proton-proton collisions. The parameters of the flash are calculated and a possibility of detection of such flash by current and future space missions is estimated.

Topic: Astrophysical signatures of cosmic strings: gravitational lensing by strings’ loops
Lecturers: Ivan Masnyak, Bohdan Hnatyk

Astronomical Observatory of Taras Shevchenko Kyiv National University

Gravitational lens systems are now a good tool for testing of different cosmological models. Their detection is based mainly on observations of their static properties, but observations show also fluctuations of image brightness. Such fluctuations are caused by changes of a source of light or by changes of a lens. These types of fluctuations are distinguished by measurement of their time correlation in different images (fluctuations of the source brightness are shifted on time delay in di®erent images). Using observational data we can recover the main characteristics of lens system and can determine what kind of object the lens is: relativistic or non-relativistic, very massive or not, and so on. In our report we consider fluctuations of image brightness, caused by relatively close to us variable astrophysical objects: binary stars [1] and cosmic string loops [2].  We show that we can distinguish lensing by such systems if we have the brightness curves of images. We apply our approach to an explanation of anomalous fluctuations of Q0957+561 A,B brightness claimed by Colley et al. [3], where, as we show, cosmic string is more promising gravitator.

1. Schneider, P., Ehlers, J. & Falco, E.E. 1992, Gravitational Lenses (Berlin:Springer-Verlag)
2. Vilenkin, A. & Sellard, E.P.S. 1994, Cosmic Strings and other Topological Defects (Cambridge: Cambridge University Press)
3. Colley, W. et al. 2003, ApJ, 587, 71

Topic: The KASCADE-Grande Experiment
M. Bruggemann1, J. van Buren2, M. Stumpert2

1Fachbereich Physik, Universitat Siegen, Germany

2Institut fur Kernphysik, Forschungszentrum Karlsruhe, Germany

The extensive air shower experiment KASCADE, located at the Forschungszentrum Karlsruhe, Germany, has been extended by a detector array consisting of 37 stations, taken from the former EAS-TOP experiment. The KASCADEGrande experiment covers an area of 0.5 km2 and measures extensive air showers from primary cosmic rays up to energies of 1EeV.  Measurements up to now indicate a rigidity dependent change of the composition around the knee, the energy range of 100Tev - 10PeV. One of main objectives of KASCADE-Grande is to study the so called iron knee, expected at around 100PeV. We will present the current experimental setup including further extensions in the form of a FADC-System and discuss reconstruction methods for obtaining basic air shower observables like electron and muon numbers.

Topic: The AMS experiment
Ana Sofia Torrento Coello, on behalf of the AMS Collaboration

CIEMAT (Madrid)

"AMS is a space-borne particle physics experiment to be installed on the International Space Station (ISS) for a three-year operation period. Its purpose is to measure the composition of charged particle cosmic rays as well as gamma ray photons in order to look for antimatter and dark matter.

Its placement on the ISS, where systematic errors due to the atmosphere are non-existent, will allow to reach sensitivities of 10^{-9} for antimatter searches. Moreover, a wide range of energies will be covered for antiproton, positron and gamma-ray spectra, where co-annihilation signatures from dark matter candidates are expected to peak in certain models.

The experiment will perform pioneering measurements of the cosmic composition to answer some of the fundamental questions in particle physics and astrophysics such as: Why is 90% of the universe not observable? Does antimatter exist in our universe? What are the properties of cosmic rays?"

Topic: CZT Detectors in Hard X-Ray Astronomy
J. S. Perkins

I will discuss the optimization of low-cost Cadmium Zinc Telluride detectors for their application in high energy X-ray Astronomy. After describing the R&D effort at Washington University, I will highlight the astrophysical topics addressed by a sensitive hard X-ray survey instrument that operates in the energy range from 10 keV to 600 keV,  like the proposed black hole finder probe EXIST.


Topic: A Double Radiator Configuration for the RICH Detector of the AMS Experiment. Implication on the Study of Isotopic Separation of Helium and Beryllium Nuclei.
Lecturers: Maria Luisa Arruda, Fernando Barao

Av. Elias Garcia, 14 1
o-andar, 1000-149 Lisboa

The Alpha Magnetic Spectrometer (AMS) to be installed on the International Space Station (ISS), in 2006, will measure cosmic ray fluxes of elements up to Iron, in the rigidity range from 1 GV to 1 TV, for at least three years. Its aims are the search for cosmic antimatter, through the detection of antinuclei with |Z| >2; the search of non-baryonic dark matter and the study of the origin and isotopic composition of cosmic rays. AMS is a large angular acceptance spectrometer composed of different subdetectors; in particular, there will be a proximity focusing Ring Imaging Cerenkov detector (RICH). This will be equipped with a mixed radiator of aerogel and a square of sodium fluoride in the center, a lateral conical mirror and a detection plane made of 680 photomultipliers and light guides. The RICH detector allows the measurement of particle electric charge, up to the iron, and velocity of the particle, the last one with a resolution of 0.1% for protons.  When a charged particle traverses a dielectric medium (radiator), with a speed greater than the speed of light in that medium, emission of Cerenkov photons occurs. These photons are distributed in a conical surface with an aperture angle (Cerenkov angle) related to the particle's velocity. The cone hits the photomultipliers plane and draws a ring with a certain geometrical acceptance and this is used to reconstruct the Cerenkov angle and therefore the particle's velocity. An implementation of a double radiator configuration, made of aerogel and sodium fluoride, on one hand allows to increase the RICH acceptance and on the other hand extends the linear momentum region covered by the detector to lower values.  Therefore there are more constraints on the propagation models of cosmic rays, based on a measurement of the ratios 3He/4He and 10Be/9Be. The measurement of the 10Be/9Be ratio will provide a determination of con nement time of the cosmic rays in the galaxy. Since 3He is essentially a secondary product coming from the spallation of 4He, its measurement will allow the determination of the mean density of interstellar material crossed.

Topic: Calibration of the KASCADE-Grande-Hadron-Calorimeter with a high-energy particle-beam
Lecturers: S.Plewnia*, Th.Berghoefer*, H.Bluemer*, J.Engler*, J.R.Hoerandel*, J. Milke*, J.Wochele*, P.Buchholz+, N.O.Hashim+, R.Lixandru+, W.Walkowiak+

*Forschungszentrum and University of Karlsruhe

+University of Siegen

The KASCADE-Grande-Experiment is a multi-detector experiment that measures extensive air showers induced by cosmic rays. One of its components is a large hadron-calorimeter with 320 m2 detection area.  In this calorimeter ionization chambers with warm liquids as active medium are used to detect and measure the hadronic component of air showers.  A smaller version of this calorimeter was used to conduct tests at the CERN-SPS in order to verify the energy calibration of the calorimeter and to study the signal development in the ionization chambers.  The energy deposit of hadrons, electrons and muons in an energy range from 15 to 350 GeV has been measured. Results of this tests shall be discussed and compared to simulations based on the GEANT/FLUKA code.

Topic: Detecting gamma rays on the ground - EAS detectors for Gamma Ray Astronomy.
Lecturers: Jordan A. Goodman

In this talk I will discuss ground based EAS detectors used to study VHE gamma rays. I will review the technique and its advantages and disadvantages. Plus I will present recent results from current  experiments and discuss future detectors.

Topic: TeV-scale Gravity: A New Window on High-energy Physics
Lecurer: Marco Cavaglia

University of Mississippi

The fundamental Planck scale may be of the order of the TeV in models with large extra dimensions. If Tev-scale gravity is realized in nature, our view of high-energy physics has to be completely rethought. Perturbative and nonperturbative gravitational events would dominate high-energy particle interactions: Kaluza-Klein modes and graviton exchange at sub-Planckian scales; black hole and brane formation at super-Planckian scales. In this scenario, Hawking evaporation could be observed in particle colliders and in ultrahigh energy cosmic ray airshowers.

TeV-scale gravitational events would also have interesting implications in cosmology and astrophysics. The phenomenology of low-energy gravitational events is significantly different from that of standard model processes.

In this lecture we discuss their experimental signatures and perspectives for discovery.

Topic: MAGIC Telescope, data analysis and first results on blazar Markarian 421 (z=0.030)
Lecurer: Daniel Mazin and Nadia Tonello for the MAGIC collaboration

Institution: Max-Planck-Institut fuer Physik, Munich

 MAGIC, the 17m imaging athmospheric Cherenkov telescope for gamma-ray  astrophysics on La Palma, started operation in October 2003.  During the ongoing commitioning phase first data have been taken.  Here we present the analysis chain of the data and preliminary  results of the well established blazar Markarian 421 (z=0.030) during  its high state in the first half of year 2004.

Topic: The performance of MAGIC Telescope for observation of Gamma Ray Bursts
Lecturer: Satoko Mizobuchi for the MAGIC collaboration

Institution: Max-Planck-Institut fuer Physik, Munich

The MAGIC Telescope has the lowest energy threshold among the ground based gamma-ray telescope and can be slewed to any direction within 20 seconds. This makes MAGIC is a unique Cherenkov telescope which can observe GRBs originating at cosmological distances. I present a study of the detection capability for GRBs with MAGIC Telescope.

Topic: Optical SETI with MAGIC.
Alexandre Armada Tella1.

1.Institut de Física d'Altes Energies (IFAE), Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain.

For almost half a century (since the 1960's) we have been looking for extraterrestial signals originated by extraterrestrial intelligent life in the radiofrequency (RF) range. However the development of the laser has made us aware that pulsed narrow beams may be ideal carriers for interstellar communications. Those features of the optical transmissions and the amazing improvement of the laser technology and power in the last years (doubling of capability every two years law) suggests that if some intelligent extraterrestrial life is trying to communicate with us, they probably do it in the optical range instead of the RF.  In this sense, the MAGIC Telescope is maybe the best tool at the moment for the detection of this pulsed signals in the optical range, due to its large reflective surface (227 m2) and sensitivity to pulses as short as 1 ns.

Topic: Microquasar Searches with the MAGIC Cherenkov Telescope
Lecturer: Núria Sidro Martin

IFAE - Universitat Autonoma de Barcelona (Spain)

Microquasars in our Galaxy are one of the most recent contribution to the high energy astrophysical sources catalog.

Microquasars are binary systems emitting X rays and producing ralativistic collimated plasma jets perpendicularly to the accretion disc. These systems behave as scaled down versions of the quasars and active galactic nuclei.

MAGIC is a 17m diameter cherenkov telescope that can detect the gammas with energy 10GeV-10TeV coming from these sources.

Here we review the detection prospects of these kind of objects.

Topic: MAGIC sensitivity for pulsed emission from γ-ray pulsars


Dept. de fisica atomica, nuclear y molecular, UCM, Ciudad Universitaria s/n, Madrid

ABSTRACT. Since their discovery, pulsars have been observed in a wide range of wavelengths. The development of several theoretical models of emission has been proposed from these data. The EGRET detector of the CGRO satellite measured pulsed emission from several high energy pulsars (up to energies around 20 GeV). The energy band between 15 - 300 GeV is at present unexplored. The ground-based Cherenkov telescope MAGIC (Major Atmospheric Gamma Imaging Cherenkov telescope) is able to observe below 100 GeV. Here we summarize (using monte-Carlo simulations) the MAGIC sensitivity for pulsar detection and its dependence with the Earth magnetic eld. The results show implications to the present theoretical models and the existence of other gamma-ray source candidates within the radio-pulsar Princeton catalog.

Topic: Observations of the Crab Nebula by the MAGIC Telescope
Lecturer: Ester Aliu

The first results of the Crab Nebula observations by the MAGIC Cerenkov telescope are presented. The data were acquired during the commissioning phase of the instrument between January and March 2004. The signal has been obtained using the False Source Method. A correction for the rotation of the field of view in the camera, due to fact that the telescope has an azimuth mount, has also been applied. Since Crab Nebula is a steady source at MAGIC energy range, these results are used to assess the performance of the telescope, e.g. the angular resolution, sensitivity and energy threshold.

Topic: Optical astronomy with Cherenkov telescopes
Lecturer: E. Ona-Wilhelmi For The MAGIC Collaboration

The poor angular resolution of imaging g-ray telescopes is offset by the large collection area of the next generation telescopes such as MAGIC (17 m diameter) which makes the study of optical emission associated with g-ray sources feasible.  In particular the optical photon flux causes an increase in the photomultiplier DC currents.  Furthermore the extremely fast response of photomultipliers (PMs) make them ideal detectors for fast (subsecond) optical transients and periodic sources like pulsars.  The detection of the optical pulse of the Crab pulsar with HEGRA CT1 and further tests have been done with a PM of the future MAGIC camera to elucidate if a detection is feasible.  The HEGRA CT1 telescope (1.8 m radius) is the smallest Cherenkov telescope which has seen the Crab optical pulsations, of which a detection can be made within 200 seconds.  The timing signal is used to derive the light of the sky background (LONS) around the Crab nebula in the Galactic plane.  For MAGIC, a hybrid photo detector (HPD) will be installed in the central pixel for this kind of studies.

Topic: MAGIC, a new generation Cherenkov Telescope for low energy gamma ray astronomy
Lecturer: Florian Goebel for the MAGIC collaboration

Institution: Max-Planck-Institut fuer Physik, Munich

The 17 m MAGIC imaging Cherenkov telescope for gamma ray astronomy with energies down to 30 GeV started operation in its final configuration in October 2003. It is currently well in its commissioning phase and the first standard sources have been recently detected.

Topic: Magnetic field generation and particle acceleration in gamma-ray burst shocks
Lecturer: Christian B. Hededal,

Astronomisk Observatorium, Copenhagen, Denmark

Gamma-ray bursts (GRBs) are among the most energetic events in the known universe. A highly relativistic fireball is ejected, in what is believed to be connected to the death of super massive stars. In most cases the burst itself is followed by an afterglow, emitted under deceleration as the fireball plunges through the circum-stellar media.

To make the right interpretations from the afterglow observations, two things need to be determined: 1) The origin and nature of the magnetic field in the fireball and 2) the particle velocity distribution function behind the shock (is Fermi acceleration actually able to produce the assumed power-law distributions?). Both are necessary in existing afterglow models to account for what is believed to be synchrotron radiation. To answer these questions, we need to understand the microphysics at play in collisionless shocks. Using 3D particle-in-cell simulations we can gain insight in the microphysical processes that take place in such shocks.

This talk presents the results of such simulations. It is shown how a Weibel-like two-stream plasma instability is able to create a strong transverse magnetic field and how particle acceleration takes place in the shock-region.

Topic: Detecting high redshift AGNs with the MAGIC Telescope
Lecturer: Roger Firpo

 IFAE (Barcelona)

Active Galactic Nuclei (AGN) have been a matter of study for the astrophysicists for a long time, but it is not been until a few years ago that they have been established as active sources in the VHE region.

The fact that only a handful of these sources have been detected is probably due to the fact that TeV photons are strongly absorbed in the extragalactic IR background. With the energy threshold of current Cherenkov telescopes (>~500 GeV), only objects closer than z~0.05 are observable.

The MAGIC Cherenkov telescope has been designed to achieve an energy threshold around 30 GeV, thus opening up the universe up to redshifts 1-5.  Since the number density of AGNs in our universe peaks at a redshift ~1-3, we expect to highly increase the AGN catalog in the VHE range.  Here we review the detection prospects for this kind of objects.

Topic: The H.E.S.S. Experiment: Status and Resent Results
Lecturer: Martin Raue for the H.E.S.S. Collaboration

Institut für Experimentalphysik, University of Hamburg

The H.E.S.S. (High Energy Stereoscopic System) Collaboration operates an array of four imaging atmospheric Cherenkov telescopes in Namibia (1800m above sea level) to observe sources of high energy gamma-rays. Each of the four telescopes has an 107 m^2 mirror and is equipped with a high resolution camera made out of 960 photo-multipliers (pixel size 0.16 deg). The telescopes are used in coincidence to carry out stereoscopic observations. This allows for an angular resolution of 0.1 deg per event, an energy resolution of 10% to 20% and an energy threshold of about 100 GeV at zenith. First operations with a single telescope started in June 2001. Since December 2003 all four telescopes are taking data. In the talk I will report the status of the experiment and present some resent results.

Topic: Measurement of the air fluorescence efficiency with the AirLight experiment
Lecturer:  Tilo Waldenmaier

The fluorescence detectors of the Pierre Auger Observatory measure the longitudinal profile of extensive air showers by detecting atmospheric fluorescence light. The charged particles of extensive air showers ionize and excite nitrogen molecules while traversing the atmosphere. In the process of de-excitation fluorescence light is emitted in the UV range. The relation between the deposited ionization energy and the number, as well as the wavelength spectrum, of emitted fluorescence photons is called fluorescence efficiency. The fluorescence efficiency mainly depends on temperature, pressure and composition (gas components, water vapor) of the air. It can also change with the energy of the ionizing particle but, at least for higher energies, this seems to be negligible. From simulations we know that most of the deposited energy of an extensive air shower in air comes from electrons and positrons with energies between 100 keV and 1 GeV.

The AirLight experiment at Forschungszentrum Karlsruhe will measure the fluorescence efficiency of electrons in air for energies ranging from ~ 0.3 to 2 MeV. The experimental setup and preliminary results will be presented.

Topic: Ultra High Energy Cosmic Rays: Toy Models and Complet Samples of Sources
Lecturers: Ioana C. Maris, Peter L. Biermann

Max Planck Institute for Radioastronomy, Bonn

We searched for directional correlations between Ultra High Energy Cosmic Rays (UHECRS) and different types of sources like Compact Steep Spectrum and Gigahertz Peaked Spectrum sources, clusters of galaxies, Gamma Ray Bursts, BL Lac objects, infrared (IRAS) bright galaxies, flat spectrum radio sources, and others. We show that there is no plausible association between the cosmic ray events and the used sample of sources because of the poor statistics: we need more UHECRs data.  However various source candidates can be used to develop toy models.  One possible toy model for accelerating particles to such high energies could be the activity of the relativistic jets in Active Galactic Nuclei. We selected the sources which are in positional coincidence with UHECRs events and have compact cores .We computed the maximum energy the particles can be accelerated to and the cosmic ray flux related to M87. Some of the sources, like 3C120, 3C147, 4C39.25 might have considerable contribution to the arriving cosmic ray flux. Other toy models could be the Gamma Ray Bursts in nearby starburst galaxies such as IC0342 from the Condon survey, or the cosmological accretion shock fronts around clusters of galaxies.