Event calendar file
3-11 July 2007
Merida, Mexico
Mexico/General timezone
- icrc2007@icrc2007.unam.mx
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HE 1.4.A
Place
Location: Merida, Mexico
Room: Yucatan II+III+IV (Fiesta Americana)
Date:
from 4 Jul 08:30 to 7 Jul 13:30
Timetable | Contribution List
Displaying 26
contributions
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26
Ultra High Energy Cosmic Rays (UHECRs) have an energy many times
greater than that of particles accelerated in colliders. The
Extended Air Showers (EAS) resulting from their interaction in the
atmosphere give us the opportunity to study not only Cosmic Rays but
also these extremely energetic cascades.
A method to calculate the Average Longitudinal Shower profile has been
applied to the Hig
... More
Presented by Mr. Gareth HUGHES
on
4/7/2007
at
14:42
There are some prerequisites to possible success in searching for small-scale
anisotropy of cosmic ray arrival directions at the highest energies. Recent claims
of autocorrelations in the data of giant extensive air shower (EAS) arrays and
presumable correlations between BL Lacertae and ultra-high energy cosmic
rays (UHECRs) incite to sift the Yakutsk array data. Present analysis is based
... More
Presented by Dr. Anatoly IVANOV
on
7/7/2007
at
18:05
A key step towards the understanding of the origin of
ultra-high energy cosmic rays is their mass composition.
Primary photons and neutrinos produce markedly different
showers from nuclei, while showers of nuclear species are
not easy to distinguish. To maximise the discrimination
with the Pierre Auger Observatory ideally all mass-sensitive
observables should be combined, but the 10% duty cy
... More
on
4/7/2007
at
17:05
The High Resolution Fly's Eye (HiRes) fluorescence detectors have been
collecting extensive air shower (EAS) data for more than 6 years . The
obtained statistics allows us to more precisely estimate the mass
composition of the ultra high energy cosmic rays (UHECR). In this study we
summarize the stereo shower parameters measurements, especially X_{max}
measurements. The sensitivity limit
... More
Presented by Yulia FEDOROVA
on
4/7/2007
at
13:54
Extensive air showers of cosmic rays ultra-high energy without muon
component registered by the Yakutsk array have been analysed. Among them
we found some clusters and these clusters correlate with pulsars. The problem
of origin showers without muons and the chemical composition of cosmic rays
are discussed.
Presented by Dr. Alexei MIKHAILOV
on
7/7/2007
at
18:17
When high-energy cosmic rays impinge on a dense dielectric medium, radio waves
are produced through the Askaryan effect. At wavelengths comparable to the
typical longitudinal size of showers produced by Ultra-High Energy cosmic rays
or neutrinos, radio signals are an extremely efficient way to detect these
particles [1]. These can be detected using the Westerbork Synthesis Radio
Telescope (WS
... More
Presented by Olaf SCHOLTEN
on
7/7/2007
at
17:53
Data from the High Resolution Fly's Eye detector that measures cosmic rays
with the fluorescence technique is used to set limits on the flux of tau
neutrinos in the energy range from 10^17 to 10^21 eV. This energy range is
particularly interesting as we expect a guaranteed flux of cosmogenic
neutrinos from the GZK mechanism.
Presented by Prof. Kai MARTENS
on
4/7/2007
at
14:06
We present results on the ultra-high energy cosmic ray spectrum as measued
by the High Resolution Fly's Eye Experiment. The spectrum is analyzed in
two different ways: monocular reconstruction and stereo reconstruction.
The monocular spectrum has the highest statistics while the stereo
spectrum has the best resolution.The monocular spectrum has a threshold of
.1 EeV while the stereo spectrum'
... More
Presented by Prof. Pierre SOKOLSKY
on
4/7/2007
at
13:42
A key feature of the Pierre Auger Observatory is its hybrid design, in
which ultra high energy cosmic rays are detected simultaneously by
fluorescence telescopes and a ground array. The two techniques see air
showers in complementary ways, providing important crosschecks and
measurement redundancy. Much of the hybrid capability stems from the
accurate geometrical reconstruction it achieves, w
... More
Presented by Dr. Bruce DAWSON
on
4/7/2007
at
15:30
At the southern site of the Pierre Auger Observatory, which is close to completion,
an exposure that significantly exceeds the largest forerunner experiments has already
been accumulated. We report a measurement of the cosmic ray energy spectrum based on
the high statistics collected by the surface detector. The methods developed to
determine the spectrum from reconstructed observables are des
... More
Presented by Dr. Markus ROTH
on
4/7/2007
at
16:06
We report on the cosmic ray spectrum obtained using the inclined events detected with
the Pierre Auger Observatory. Showers with zenith angles between 60$^\circ$ and
80$^\circ$ recorded in the period between January 1st, 2004 and December 31st, 2006
are analysed. Showers are first reconstructed in arrival direction and then fitted to
density maps of the muon numbers obtained from $10^{19}$eV s
... More
Presented by Mrs. Pedro FACAL
on
4/7/2007
at
16:18
Three years of data collected with the fluorescence detector in coincidence with at
least one station of the surface detector array ('hybrid data') are used to measure
the flux and energy spectrum of cosmic rays above about 10^{18}eV. The hybrid
measurement extends the spectrum measured with the surface detector data alone
towards lower energies, and provides a cross-check in the overlap regio
... More
Presented by Dr. Lorenzo PERRONE
on
4/7/2007
at
16:30
The HiRes Experiment has observed the GZK Cutoff. We will present power law fits to
the latest HiRes monocular spectra, and use the results of these fits to argue that
the GZK Cutoff has been definitively observed in that dataset. We will also present
fits to a uniform sorce density model.
Presented by Prof. Douglas BERGMAN
on
4/7/2007
at
13:30
The Telescope Array (TA) experiment is an array of surface detectors
surrounded by three stations of fluorescence telescopes in Utah, USA, to
investigate the origin of the highest energy cosmic rays of energy beyond 10^
{20}eV. We deployed about 500 plastic scintillation counters on a grid with 1.2
km spacing as a surface array by March 2007. Each surface detector is outfitted
with double
... More
Presented by Dr. Hiroyuki SAGAWA
on
7/7/2007
at
17:17
The reconstruction of extensive air showers (arrival direction, core position and
energy estimation) by the
surface detector (SD) of the Pierre Auger Observatory is discussed together with the
corresponding accuracy.
We determine the angular reconstruction accuracy as a function of the station
multiplicity: the resolution
obtained by the SD only is in agreement with the one obtained from h
... More
Presented by Dr. Simone MALDERA
on
4/7/2007
at
15:54
We have searched for intermediate-scale anisotropy in the data of
the HiRes experiment, in particular the monocular data from the
HiRes-II detector. These data were collected between December, 1999,
and August, 2005. We see a deficit of events near the direction of
the galactic anticenter, very close to the location of the deficit
seen by AGASA. Because of low exposure in summer months we
... More
Presented by Prof. Gordon THOMSON
on
4/7/2007
at
14:30
Several analyses of the data collected by other experiments have
found an excess of cosmic rays in correlation with subclasses of
BL Lacs. We test these analyses with the data from the Pierre
Auger Observatory, and report on the results of our searches.
Presented by Dr. Diego HARARI
on
4/7/2007
at
18:05
Data taken at the Pierre Auger Observatory are used to search for air
showers initiated by ultra-high energy (UHE) photons.
The results of
searches for UHE photons are reported from hybrid observations
(fluorescence and array detectors). Additionally, using the larger
data set from the array detectors alone, a more stringent test of
predicted large photon fluxes is presented.
Presented by Matthew HEALY
on
4/7/2007
at
17:15
The Telescope Array (TA) is a hybrid experiment of an air shower array
and fluorescence telescopes installed in Utah, USA. It aims at
drawing a conclusion on the (non-)existence of the GZK cutoff
reported controversially by the AGASA and HiRes experiments. An
anisotropy of the UHECR arrival directions will be studied in
the northern hemisphere where the galactic disturbances are
small. The u
... More
Presented by Masaki FUKUSHIMA
on
7/7/2007
at
17:05
The clustering properties of the arrival directions of ultra high energy cosmic
rays encode important information to determine their origin, composition,
and to constrain galactic and extragalactic magnetic fields. We present here
the results of a variety of analyses of data from the Pierre Auger Observatory
as a function of the angular scale and the energy threshold. We compare our
resu
... More
Presented by Dr. Silvia MOLLERACH
on
4/7/2007
at
18:15
The Pierre Auger Observatory has been collecting data in a stable
manner since January 2004. We present here a study of the cosmic ray
composition using events recorded in hybrid mode during the first
three years of data taking. These are air showers observed by the
fluorescence detector as well as the surface detector, so the depth
of shower maximum (Xmax) is measured directly. T
... More
Presented by Dr. Michael UNGER
on
4/7/2007
at
17:25
The Pierre Auger Observatory employs a wide range of atmospheric monitoring
instruments: two laser facilities; elastic lidar stations; aerosol phase
function monitors; a horizontal attenuation monitor; star monitors;
weather stations; and balloon soundings. Using all available analyzed
atmospheric data we tested the impact on the shower reconstruction, namely
on the shower energy and the posi
... More
Presented by Michael PROUZA
on
4/7/2007
at
15:42
We have developed detector simulators for the TA fluorescence telescopes (FD)
and the surface particle detector array. In this paper we describe a new
method to evaluate the TA-FD aperture with a Monte-Carlo technique. Since the
field of view and the effective area for the FDs are quite large, a considerable
CPU cost is required for air shower simulations in the full observable region. In
... More
Presented by Dr. Yoshiki TSUNESADA
on
7/7/2007
at
17:41
The Pierre Auger Observatory allows the measurement of both
longitudinal profiles and lateral particle distributions of high
energy showers. The former trace the overall shower development,
mainly of the electromagnetic component close to the core, and the
latter reflect the particle densities in the tail of the shower far
away from the core, and are sensitive to both the muonic and
electrom
... More
Presented by Dr. Ralph ENGEL
on
4/7/2007
at
17:35
The fluorescence measurement is the key in observations of ultra high energy cosmic
rays and in determinations of their primary energies in the TA experiment. All the
fluorescence detectors of TA will be in operation from June 2007. In this talk, we
will present the characteristics of the telescopes and the status of the associated
systems including for the atmospheric monitoring and the PMT c
... More
Presented by Dr. Shoichi OGIO
on
7/7/2007
at
17:29
The Southern part of the Pierre Auger Observatory, which is nearing completion, has
been in stable operation since January 2004 whilst it has grown in size. The large
sample of data collected so far has led to a significant improvement to the energy
spectrum of UHE cosmic rays over that previously reported by the Pierre Auger
Observatory, both in with regard to statistics and systematic uncert
... More
Presented by Dr. Yamamoto TOKANATSU
on
4/7/2007
at
16:42
