Publications (79)
High Energy Neutrinos from Cosmic Ray Interactions in Clusters of Galaxies
Daniel De Marco, Pasquale Blasi, Patricia Hansen +1
The spatial clustering of galaxies in galaxy clusters implies that the background of infrared (IR) light in the intracluster medium (ICM) may exceed the universal background. Cosmi…
The beginning of cosmic ray astronomy
Todor Stanev
We discuss the anisotropic arrival directions of the ultra high energy cosmic rays detected by Auger which I consider one of the biggest discoverie in astrophysics during the last…
The large scale structure of the Galactic magnetic field and High Energy Cosmic Ray anisotropy
Jaime Alvarez-Muñiz, Todor Stanev
The magnetic field in our Galaxy is not well known and is difficult to measure. A spiral regular field in the disk between the Galactic arms is favored by observations, however it…
Numerical propagation of high energy cosmic rays in the Galaxy I: technical issues
Daniel De Marco, Pasquale Blasi, Todor Stanev
We present the results of a numerical simulation of propagation of cosmic rays with energy above eV in a complex magnetic field, made in general of a large scale componen…
Hadronic interaction model Sibyll 2.3d and extensive air showers
Felix Riehn, Ralph Engel, Anatoli Fedynitch +2
We present a new version of the hadron interaction event generator Sibyll. While the core ideas of the model have been preserved, the new version handles the production of baryon p…
The end of the galactic cosmic ray spectrum
Todor Stanev
We discuss the region of transition between galactic and extragalactic cosmic rays. The exact shapes and compositions of these two components contains information about important p…
APS Neutrino Study: Report of the Neutrino Astrophysics and Cosmology Working Group
Steve W. Barwick, John F. Beacom, Vince Cianciolo +11
In 2002, Ray Davis and Masatoshi Koshiba were awarded the Nobel Prize in Physics ``for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos…
Neutrino production in UHECR proton interactions in the infrared background
Todor Stanev
We discuss the contribution of proton photoproduction interactions on the isotropic infrared/optical background to the cosmic neutrino fluxes. This contribution has a strong depend…
Ultra High Energy Cosmic Rays
Todor Stanev
We discuss theoretical issues and experimental data that brought the ultra high energy cosmic rays in the list of Nature's greatest puzzles. After many years of research we still d…
IceTop Status in 2004
Todor Stanev, Ralf Ulrich
IceTop is the surface component of IceCube neutrino telescope. Goals, plans and status of IceTop in 2004 are reported
Propagation of ultra high energy cosmic rays
Todor Stanev
We briefly describe the energy loss processes of ultrahigh energy protons, heavier nuclei and gamma rays in interactions with the universal photon fields of the Universe. We then d…
Cosmic backgrounds due to the formation of the first generation of supermassive black holes
Peter L. Biermann, Biman B. Nath, Laurenţiu I. Caramete +3
The statistics of black holes and their masses strongly suggests that their mass distribution has a cutoff towards lower masses near M. This is consiste…
Ultra high energy cosmic rays: A review
Todor Stanev
We present the main results on the energy spectrum and composition of the highest energy cosmic rays of energy exceeding 10 eV obtained by the High Resolution Fly's Eye and…
The transition from galactic to extragalactic cosmic rays
Todor Stanev
We discuss the region of transition between galactic and extragalactic cosmic rays. The exact shapes and compositions of these two components contains information about important p…
Ultrahigh Energy Cosmic Rays
Antoine Letessier-Selvon, Todor Stanev
This is a review of the most resent results from the investigation of the Ultrahigh Energy Cosmic Rays, particles of energy exceeding 10 eV. After a general introduction to…
Influence of shower fluctuations and primary composition on studies of the shower longitudinal development
Jaime Alvarez-Muñiz, Ralph Engel, T. K. Gaisser +2
We study the influence of shower fluctuations, and the possible presence of different nuclear species in the primary cosmic ray spectrum, on the experimental determination of both…
The Cosmic Ray Distribution in Sagittarius B
Roland M. Crocker, David Jones, Raymond J. Protheroe +5
The HESS instrument has observed a diffuse flux of ~ TeV gamma rays from a large solid angle around the Galactic center (GC). This emission is correlated with the distribution of g…
Antiprotons at Solar Maximum
John W. Bieber, R. A. Burger, Ralph Engel +3
New measurements with good statistics will make it possible to observe the time variation of cosmic antiprotons at 1 AU through the approaching peak of solar activity. We report a…
TeV Gamma Rays from Geminga and the Origin of the GeV Positron Excess
Hasan Yuksel, Matthew D. Kistler, Todor Stanev
The Geminga pulsar has long been one of the most intriguing MeV-GeV gamma-ray point sources. We examine the implications of the recent Milagro detection of extended, multi-TeV gamm…
Cut-offs and pile-ups in shock acceleration spectra
R. J. Protheroe, Todor Stanev
We have examined cutoffs and pile-ups due to various processes in the spectra of particles produced by shock acceleration, and found that, even in the absence of energy losses, the…
High-energy Cosmic Rays
Thomas K. Gaisser, Todor Stanev
After a brief review of galactic cosmic rays in the GeV to TeV energy range, we describe some current problems of interest for particles of very high energy. Particularly interesti…
High Energy Neutrinos: Sources and Fluxes
Todor Stanev
We discuss briefly the potential sources of high energy astrophysical neutrinos and show estimates of the neutrino fluxes that they can produce. A special attention is paid to the…
Data-driven model of the cosmic-ray flux and mass composition from 10 GeV to GeV
Hans Dembinski, Ralph Engel, Anatoli Fedynitch +3
We present a new parametrization of the cosmic-ray flux and its mass composition over an energy range from 10 GeV to GeV. Our approach is data-driven and relies on theore…
Pathlength distribution of atmospheric neutrinos
T. K. Gaisser, Todor Stanev
We present the distribution of the production heights of atmsopheric neutrinos as a function of zenith angle and neutrino energy. The distributions can be used as the input for eva…
Atmospheric neutrino challenges
Todor Stanev
We briefly review the improvements in the predictions of atmospheric neutrino fluxes since the NOW2000 workshop. In spite of the great progress in calculational technique the predi…
Predicted power in ultra high energy cosmic rays from active galaxies
Laurentiu I. Caramete, Oana Tascau, Peter L. Biermann +1
Context: As more and more data are collected by cosmic ray experiments such as the Pierre Auger Observatory and Telescope Array (TA), the search for the sources of the Ultra High E…
A new version of the event generator Sibyll
Felix Riehn, Ralph Engel, Anatoli Fedynitch +2
The event generator Sibyll can be used for the simulation of hadronic multiparticle production up to the highest cosmic ray energies. It is optimized for providing an economic desc…
Charm production in SIBYLL
Ralph Engel, Anatoli Fedynitch, Thomas K. Gaisser +2
SIBYLL 2.1 is an event generator for hadron interactions at the highest energies. It is commonly used to analyze and interpret extensive air shower measurements. In light of the fi…
Neutrinos: the Key to UHE Cosmic Rays
David Seckel, Todor Stanev
Observations of ultrahigh energy cosmic rays (UHECR) do not uniquely determine both the injection spectrum and the evolution model for UHECR sources - primarily because interaction…
Ultrahigh Energy Cosmic Rays and Neutrinos
Todor Stanev
We discuss the relation between the highest energy cosmic rays (UHECR) and UHE neutrinos. The neutrinos produced in the sources of optically thin astrophysical sources have been li…
The Centaurus A Ultrahigh-Energy Cosmic Ray Excess and the Local Extragalactic Magnetic Field
Hasan Yuksel, Todor Stanev, Matthew D. Kistler +1
The ultrahigh-energy cosmic-ray anisotropies discovered by the Pierre Auger Observatory give the potential to finally address both the particles' origins and properties of the near…
Ultra high energy cosmic rays and the large scale structure of the galactic magnetic field
Todor Stanev
We study the deflection of ultra high energy cosmic ray protons in different models of the regular galactic magnetic field. Such particles have gyroradii well in excess of 1 kpc an…
Propagation of ultra-high energy protons in the nearby universe
Todor Stanev, Ralph Engel, Anita Muecke +2
We present a new calculation of the propagation of protons with energies above eV over distances of up to several hundred Mpc. The calculation is based on a Monte Carlo a…
Study of the Correlations Between the Highest Energy Cosmic Ray Showers and Gamma Ray Bursts
Todor Stanev, Robert Schaefer, Alan Watson
We examine the correlation between the arrival direction of ultra high energy cosmic ray showers and gamma ray bursts in the third BATSE catalog. We find no correlation between the…
Hybrid simulations of extensive air showers
Jaime Alvarez-Muñiz, Ralph Engel, T. K. Gaisser +2
We present a fast one dimensional hybrid method to efficiently simulate extensive air showers up to the highest observed energies. Based on precalculated pion showers and a bootstr…
Atmospheric neutrino flux above 1 GeV
Vivek Agrawal, T. K. Gaisser, Paolo Lipari +1
In this paper we extend an earlier calculation of the flux of atmospheric neutrinos to higher energy. The earlier calculation of the neutrino flux below 3 GeV has been used for cal…
Cosmogenic Neutrinos from Cosmic Ray Interactions with Extragalactic Infrared Photons
Daniel De Marco, Todor Stanev, F. W. Stecker
We discuss the production of cosmogenic neutrinos on extragalactic infrared photons in a model of its cosmological evolution. The relative importance of these infrared photons as a…
Constraints on the Extragalactic Infrared Background from Gamma Ray Observations of Mrk 501
Todor Stanev, Alberto Franceschini
We use the new results of the HEGRA detector on the TeV gamma-ray emission from MKN 501 to set upper limits on the energy density of the cosmic infrared background (CIRB). Contrary…
Calculation of conventional and prompt lepton fluxes at very high energy
Anatoli Fedynitch, Ralph Engel, Thomas K. Gaisser +2
An efficient method for calculating inclusive conventional and prompt atmospheric leptons fluxes is presented. The coupled cascade equations are solved numerically by formulating t…
Limits on Topological Defects Models of the Ultrahigh Energy Cosmic Rays
R. J. Protheroe, Todor Stanev
Using the propagation of ultra high energy nucleons, photons and electrons in the universal radiation backgrounds, we obtain limits on the luminosity of topological defects scenari…
Possible tau appearance experiment with atmospheric neutrinos
Todor Stanev
We suggest an experimental measurement that could detect the appearance of the tau neutrinos in muon to tau neutrino oscillations of atmospheric neutrinos by measuring the energy s…
Pion production in proton collisions with light nuclei: implications for atmospheric neutrinos
Ralph Engel, T. K. Gaisser, Todor Stanev
Differences among calculations of the atmospheric neutrino beam can be traced in large part to differences in the representation of pion production by protons interacting with nucl…
Geomagnetic Effects on Atmospheric Neutrinos
Paolo Lipari, T. K. Gaisser, Todor Stanev
Geomagnetic effects distort the zenith angle distribution of sub--GeV and few--GeV atmospheric neutrinos, breaking the up--down symmetry that would be present in the absence of neu…
UHECR propagation in the Galaxy: clustering versus isotropy
Jaime Alvarez-Muñiz, Ralph Engel, Todor Stanev
Recently the AGASA Collaboration presented data suggesting a significant clustering of ultra-high energy cosmic rays coming from the outer Galaxy region. In this paper we calculate…
Ultra High Energy Cosmic Rays: origin and propagation
Todor Stanev
We discuss the basic difficulties in understanding the origin of the highest energy particles in the Universe - the ultrahigh energy cosmic rays (UHECR). It is difficult to imagine…
The Nature and Origin of Ultra-High Energy Cosmic Ray Particles
Peter L. Biermann, Laurentiu I. Caramete, Federico Fraschetti +9
We outline two concepts to explain Ultra High Energy Cosmic Rays (UHECRs), one based on radio galaxies and their relativistic jets and terminal hot spots, and one based on relativi…
Neutrinos and cosmic rays
Thomas K. Gaisser, Todor Stanev
In this paper we review the status of the search for high-energy neutrinos from outside the solar system and discuss the implications for the origin and propagation of cosmic rays.…
Ultra high energy cosmic rays and neutrinos after Auger
Todor Stanev
We discuss the main results that were recently published by the Auger Collaboration and their impact on our knowledge of the ultra high energy cosmic rays and neutrinos.
Neutrinos from propagation of ultra-high energy protons
Ralph Engel, David Seckel, Todor Stanev
We present a calculation of the production of neutrinos during propagation of ultra-high energy cosmic rays from their astrophysical sources to us. Photoproduction interactions are…
Proton-proton Cross Section at sqrt(s) \sim 30 TeV
Ralph Engel, T. K. Gaisser, Paolo Lipari +1
There are both theoretical and experimental uncertainties in using data from cosmic-ray air showers to estimate hadronic cross sections above accelerator energies. We outline these…
Cosmic PeV Neutrinos and the Sources of Ultrahigh Energy Protons
Matthew D. Kistler, Todor Stanev, Hasan Yuksel
The IceCube experiment recently detected the first flux of high-energy neutrinos in excess of atmospheric backgrounds. We examine whether these neutrinos originate from within the…
Sibyll with charm
Eun-Joo Ahn, Ralph Engel, Thomas K. Gaisser +2
The cosmic ray interaction event generator Sibyll is widely used in extensive air shower simulations for cosmic ray and neutrino experiments. Charmed particle production has been a…
Status, performance, and first results of the IceTop array
Todor Stanev
We describe the design and performance of IceTop, the air shower array on top of the IceCube neutrino detector. After the 2008/09 antarctic summer season both detectors are deploye…
The nature of the highest energy cosmic rays
Todor Stanev, H. P. Vankov
Ultra high energy gamma rays produce electron--positron pairs in interactions on the geomagnetic field. The pair electrons suffer magnetic bremsstrahlung and the energy of the prim…
Muon Flux at the Geographical South Pole
X. Bai, T. K. Gaisser, A. Karle +3
The muon flux at the South-Pole was measured for five zenith angles, , , , and with a scintillator muon telescope…
The hadronic interaction model SIBYLL 2.3c and Feynman scaling
Felix Riehn, Hans P. Dembinski, Ralph Engel +3
The Monte Carlo model Sibyll has been designed for efficient simulation of hadronic multiparticle production up to the highest energies as needed for interpreting cosmic ray measur…
Comparison of Atmospheric Neutrino Flux Calculations at Low Energies
T. K. Gaisser, M. Honda, K. Kasahara +4
We compare several different calculations of the atmospheric neutrino flux in the energy range relevant for contained neutrino interactions, and we identify the major sources of di…
Monte-Carlo simulations of photohadronic processes in astrophysics
A. Muecke, Ralph Engel, J. P. Rachen +2
A new Monte Carlo program for photohadronic interactions of relativistic nucleons with an ambient photon radiation field is presented. The event generator is designed to fulfil typ…
On the shape of the UHE cosmic ray spectrum
Daniel De Marco, Todor Stanev
We fit the ultra high energy cosmic ray spectra above 10 eV with different injection spectra at cosmic ray sources that are uniformly and homogeneously distributed in the Un…
Propagation of ultra-high energy protons in regular extragalactic magnetic fields
Todor Stanev, David Seckel, Ralph Engel
We study the proton flux expected from sources of ultra high energy cosmic rays (UHECR) in the presence of regular extragalactic magnetic fields. It is assumed that a local source…
Atmospheric shower fluctuations and the constant intensity cut method
Jaime Alvarez-Muniz, Ralph Engel, T. K. Gaisser +2
We explore the constant intensity cut method that is widely used for the derivation of the cosmic ray energy spectrum, for comparisons of data obtained at different atmospheric dep…
The IceTop experiment in 2010
Todor Stanev
We present the current status of the IceTop air shower array on top of the IceCube neutrino detector that IceTop can use as a huge detector of TeV muons. We laos give a brief discu…
The Galactic Wind Haze and its -spectrum
Nayantara Gupta, Biman B. Nath, Peter L. Biermann +3
We study the possibility that the gamma ray emission in the Fermi bubbles observed is produced by cosmic ray electrons with a spectrum similar to Galactic cosmic rays. We argue tha…
Correlation of the HIghest Energy Cosmic Rays with the Supergalactic Plane
Todor Stanev
We examine the anisotropy of the arrival directions of twenty seven ultra high energy cosmic rays detected by the Pierre Auger Collaboration. We confirm the anisotropy of the arriv…
High energy astrophysical processes
Todor Stanev
We briefly review the high energy astrophysical processes that are related to the production of high energy -ray and neutrino signals and are likely to be important for the ene…
Cosmic Ray Energy Spectrum from Measurements of Air Showers
Thomas K. Gaisser, Todor Stanev, Serap Tilav
This review focuses on high-energy cosmic rays in the PeV energy range and above. Of particular interest is the knee of the spectrum around 3 PeV and the transition from cosmic ray…
The origin of the highest energy cosmic rays Do all roads lead back to Virgo?
Eun-Joo Ahn, Gustavo Medina-Tanco, Peter L. Biermann +1
Introducing a simple Galactic wind model patterned after the solar wind we show that back-tracing the orbits of the highest energy cosmic events suggests that they may all come fro…
On the Luminosity of the Ultra High Energy Cosmic Rays Sources
Todor Stanev
The energy density of the Ultra High Energy Cosmic Rays (UHECR) in the Universe is a very important parameter for the solution of the puzzle of their origin. It defines the luminos…
The hadronic interaction model Sibyll-2.3c and inclusive lepton fluxes
Anatoli Fedynitch, Felix Riehn, Ralph Engel +2
Muons and neutrinos from cosmic ray interactions in the atmosphere originate from decays of mesons in air-showers. Sibyll-2.3c aims to give a precise description of hadronic intera…
Extragalactic ultra high energy cosmic rays, II. Comparison with experimental data
Joerg P. Rachen, Todor Stanev, Peter L. Biermann
We compare the expected contribution of FR-II hot spots to the ultra-high energy cosmic ray spectrum (Rachen & Biermann 1993, A&A in press, BB paper astro-ph/9301010) to improved e…
Ultra high energy neutrinos: the key to ultra high energy cosmic rays
Todor Stanev
We discuss the relation between the acceleration spectra of extragalactic cosmic ray protons and the luminosity and cosmological evolution of their sources and the production of ul…
The Origin of Galactic Cosmic Rays
Peter L. Biermann, T. K. Gaisser, Todor Stanev
Motivated by recent measurements of the major components of the cosmic radiation around 10 TeV/nucleon and above, we discuss the phenomenology of a model in which there are two dis…
Charge ratio of muons from atmospheric neutrinos
T. K. Gaisser, Todor Stanev
We calculate the intensities and angular distributions of positive and negative muons produced by atmospheric neutrinos. We comment on some sources of uncertainty in the charge rat…
The origin of cosmic rays: Explosions of massive stars with magnetic winds and their supernova mechanism
Peter L. Biermann, Julia K. Becker, Jens Dreyer +3
One prediction of particle acceleration in the supernova remnants in the magnetic wind of exploding Wolf Rayet and Red Super Giant stars is that the final spectrum is a composition…
Numerical Propagation of Cosmic Rays in the Galaxy
Daniel De Marco, Pasquale Blasi, Todor Stanev
We present a Monte-Carlo (MC) calculation of the propagation of cosmic ray protons in the Galaxy for energies above 1 PeV. We discuss the relative strengths of competing effects su…
Ultrahigh Energy Cosmic Rays: Review of the Current Situation
Todor Stanev
We describe the current situation of the data on the highest energy particles in the Universe - the ultrahigh energy cosmic rays. The new results in the field come from the Telesco…
The WMAP haze from the Galactic Center region due to massive star explosions and a reduced cosmic ray scale height
Peter L. Biermann, Julia K. Becker, Gabriel Caceres +3
One important prediction of acceleration of particles in the supernova caused shock in the magnetic wind of exploding Wolf Rayet and Red Super Giant stars is the production of an e…
The arrival directions of the most energetic cosmic rays
Todor Stanev, Peter Biermann, Jeremy Lloyd-Evans +2
In this Letter we examine the arrival directions of the most energetic cosmic rays (E > 2 * 10^19 eV) detected by several air shower experiments. We find that data taken by differe…
Cosmic ray event generator Sibyll 2.1
Eun-Joo Ahn, Ralph Engel, Thomas K. Gaisser +2
The cosmic ray interaction event generator Sibyll is widely used in extensive air shower simulations. We describe in detail the properties of Sibyll 2.1 and the differences with th…