1. The muon component of extensive air showers above 10[sup]17.5 eV measured with the Pierre Auger ObservatoryLukas Zehrer, Marko Zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Marta Trini, Samo Stanič, Gašper Kukec Mezek, Andrej Filipčič, Federico Sánchez, 2019, published scientific conference contribution Found in: ključnih besedah Keywords: ultra-high energy cosmic rays, Pierre Auger Observatory, extensive air showers, muon shower component Published: 29.11.2020; Views: 1763; Downloads: 0
Fulltext (784,63 KB) |
2. Measurements of Xmax above 10[sup]17 eV with the fluorescence detector of the Pierre Auger Observatorymarko zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Darko Veberič, Marta Trini, Samo Stanič, Ahmed Saleh, Gašper Kukec Mezek, Andrej Filipčič, Alessio Porcelli, 2015, published scientific conference contribution Abstract: For the first time the Pierre Auger Collaboration
presents〈Xmax〉and σ(Xmax) measurements covering nearly three decades of energy. In this analysis we include
new Xmax data obtained with the High Elevation Auger
Telescopes (HEAT) enhancement. The HEAT telescopes cover
a field of view ranging from 30◦ to 60◦ of elevation and are
located next to one of the standard fluorescence detector sites
(Coihueco). The combination of the HEAT and Coihueco telescopes
covers a field of view from ∼2◦ up to ∼60◦ of elevation. Thus,
the combination can sample the longitudinal profile of nearby
lower energy showers, allowing us to extend the energy range
down to 10[sup]17 eV. Found in: ključnih besedah Summary of found: ... extensive atmospheric showers,
longitudinal shower profile,
depth of the shower... Keywords: extensive atmospheric showers, longitudinal shower profile, depth of the shower maximum, Pierre Auger Observatory Published: 03.03.2016; Views: 4459; Downloads: 226
Fulltext (718,30 KB) |
3. Search for Ultra-relativistic Magnetic Monopoles with the Pierre Auger Observatorymarko zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Darko Veberič, Marta Trini, Samo Stanič, Ahmed Saleh, Gašper Kukec Mezek, Andrej Filipčič, Toshihiro Fujii, 2015, published scientific conference contribution Abstract: Ultra-relativistic magnetic monopoles, possibly a relic of
phase transitions in the early universe, would deposit an
amount of energy comparable to UHECRs in their passage
through the atmosphere, producing highly distinctive air
shower profiles. We have performed a search for
ultra-relativistic magnetic monopoles in the sample of air
showers with profiles measured by the fluorescence detector of
the Pierre Auger Observatory. No candidate was found to satisfy
our selection criteria and we establish upper limits on the
flux of ultra-relativistic magnetic monopoles - the first from
an UHECR detector - improving over previous results by up to an
order of magnitude. Found in: ključnih besedah Summary of found: ...ultra-relativistic magnetic monopoles,
extensive air showers,
Pierre Auger Observatory... Keywords: ultra-relativistic magnetic monopoles, extensive air showers, Pierre Auger Observatory Published: 03.03.2016; Views: 3762; Downloads: 185
Fulltext (188,24 KB) |
4. Azimuthal asymmetry in the risetime of the Surface Detector signals of the Pierre Auger Observatorymarko zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Darko Veberič, Marta Trini, Samo Stanič, Ahmed Saleh, Gašper Kukec Mezek, Andrej Filipčič, Ignacio Minaya, 2015, published scientific conference contribution Abstract: The azimuthal asymmetry in the risetime of signals in Auger
surface detector stations is a source of information on shower
development. The azimuthal asymmetry is due to a combination of
the longitudinal evolution of the shower and geometrical
effects related to the angles of incidence of the particles
into the detectors. The magnitude of the effect depends upon
the zenith angle and state of development of the shower and
thus provides a novel observable sensitive to the mass
composition of cosmic rays above 3 × 10[sup]18 eV. By comparing
measurements with predictions from shower simulations, we find
for both of our adopted models of hadronic physics (QGSJetII-
04 and Epos-LHC) an indication that the mean cosmic-ray mass
increases with energy, as has been inferred from other studies.
However the absolute values derived for the mass are dependent
on the shower model and on the range of distance from the
shower core selected. Thus the method has uncovered further
deficiencies in our understanding of shower modelling that must
be resolved before the mass composition can be inferred from
(sec θ)max. Found in: ključnih besedah Summary of found: ...vatory,
Surface Detector,
risetime of detector signal,
azimuthal asymmetry,
extensive air showers... Keywords: Pierre Auger Observatory, Surface Detector, risetime of detector signal, azimuthal asymmetry, extensive air showers Published: 03.03.2016; Views: 3909; Downloads: 184
Fulltext (243,04 KB) |
5. Extension of the measurement of the proton-air cross section with the Pierre Auger Observatorymarko zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Darko Veberič, Marta Trini, Samo Stanič, Ahmed Saleh, Gašper Kukec Mezek, Andrej Filipčič, Ralf Ulrich, 2015, published scientific conference contribution Abstract: With hybrid data of the Pierre Auger Observatory it is possible
to measure the cross section of proton-air collisions at
energies far beyond the reach of the LHC. Since the first
measurement by the Pierre Auger Collaboration the event
statistics has increased significantly. The proton-air
cross section is now estimated in the two energy intervals in
lg(E/eV) from 17.8 to 18 and from 18 to 18.5. These energies
are chosen so that they maximise the available event statistics
and at the same time lie in the region most compatible with a
significant primary proton fraction. Of these data, only the
20% of most proton-like events are considered for the
measurement. Furthermore, with a new generation of hadronic
interaction models which have been tuned to LHC data, the
model-dependent uncertainties of the measurement are re-visited. Found in: ključnih besedah Summary of found: ...Pierre Auger Observatory,
extensive air showers,
proton-air cross section,
hadronic interaction models... Keywords: Pierre Auger Observatory, extensive air showers, proton-air cross section, hadronic interaction models Published: 03.03.2016; Views: 3625; Downloads: 186
Fulltext (114,02 KB) |
6. Measurement of the average electromagnetic longitudinal shower profile at the Pierre Auger Observatorymarko zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Darko Veberič, Marta Trini, Samo Stanič, Ahmed Saleh, Gašper Kukec Mezek, Andrej Filipčič, Francisco Diogo, 2015, published scientific conference contribution Abstract: In addition to the standard Xmax and energy, the longitudinal
profiles of extensive air showers contain some more interesting
information. For energies above 10[sup]17.8 eV, we present the
average profiles as a function of atmospheric depth measured
for the first time at the Pierre Auger Observatory. The profile
shapes for different energy ranges are all well reproduced by a
Gaisser-Hillas function within the range studied. A detailed
analysis of the systematic uncertainties is performed using
data and a full detector simulation, and the results are
compared with predictions of hadronic interaction models for different primaries. Found in: ključnih besedah Summary of found: ...standard Xmax and energy, the longitudinal
profiles of extensive air showers contain some more interesting
information.... Keywords: Pierre Auger Observatory, extensive air showers, longitudinal shower profile, Gaisser-Hillas finction Published: 03.03.2016; Views: 3364; Downloads: 182
Fulltext (684,20 KB) |
7. Studies in the atmospheric monitoring at the Pierre Auger Observatory using the upgraded Central Laser Facilitymarko zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Darko Veberič, Marta Trini, Samo Stanič, Ahmed Saleh, Gašper Kukec Mezek, Andrej Filipčič, Carlos Medina-Hernandez, 2015, published scientific conference contribution Abstract: The Fluorescence Detector (FD) at the Pierre Auger Observatory
measures the intensity of the scattered light from laser tracks
generated by the Central Laser Facility (CLF) and the eXtreme
Laser Facility (XLF) to monitor and estimate the vertical
aerosol optical depth (τ(z,t)). This measurement is needed to
obtain unbiased and reliable FD measurements of the arrival
direction and energy of the primary cosmic ray, and the depth
of the maximum shower development. The CLF was upgraded
substantially in 2013 with the addition of a solid state laser,
new generation GPS, a robotic beam calibration system, better
thermal and dust isolation, and improved software. The upgrade
also included a back-scatter Raman LIDAR to measure τ(z,t).
The new features and applications of the upgraded instrument
are described. These include the laser energy calibration
and the atmospheric monitoring measurements. The first τ(z,t)
results and comparisons after the upgrade are presented using different methods. The first method compares the FD hourly
response to the scattered light from the CLF (or XLF) against
a reference hourly profile measured during a clear night where
zero aerosol contents are assumed. The second method simulates
FD responses with different atmospheric parameters and selects the parameters that provide the best fit to the actual FD
response. A third method uses the new Raman LIDAR receiver
in-situ to measure the back-scatter light from the CLF laser.
The results show a good data agreement for the first and second
methods using FD stations located at the same distance from the
facilities. Preliminary results of τ(z,t) using the Raman LIDAR
are presented as well. Found in: ključnih besedah Summary of found: ...Pierre Auger Observatory,
extensive air showers,
the Fluorescence Detector,
atmospheric monitoring,
vertical aer... Keywords: Pierre Auger Observatory, extensive air showers, the Fluorescence Detector, atmospheric monitoring, vertical aerosol optical depth, the Central Laser Facility, the eXtreme Laser Facility Published: 03.03.2016; Views: 3952; Downloads: 174
Fulltext (3,96 MB) |
8. The Energy Content of Extensive Air Showers in the Radio Frequency Range of 30-80 MHzmarko zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Darko Veberič, Marta Trini, Samo Stanič, Ahmed Saleh, Gašper Kukec Mezek, Andrej Filipčič, Christian Glaser, 2015, published scientific conference contribution Abstract: At the Auger Engineering Radio Array (AERA) of the Pierre Auger
Observatory, we have developed a new method to measure the
total amount of energy that is transferred from the primary
cosmic ray into radio emission. We find that this radiation
energy is an estimator of the cosmic ray energy. It scales
quadratically with the cosmic ray energy, as expected for
coherent emission. We measure 15.8 MeV of radiation energy for
a 1 EeV air shower arriving perpendicular to the geomagnetic
field at the Auger site, in the frequency band of the detector
from 30 to 80 MHz. These observations are compared to the data
of the surface detector of the Observatory, which provide
well-calibrated energies and arrival directions of the cosmic
rays. We find energy resolutions of the radio reconstruction
of 22% for the complete data set, and 17% for a high-quality
subset containing only events with at least five stations with
signal. Found in: ključnih besedah Keywords: Pierre Auger Observatory, the Auger Engineering Radio Array (AERA), extensive air showers, radio reconstruction: energy resolution Published: 03.03.2016; Views: 3795; Downloads: 199
Fulltext (574,66 KB) |
9. Status and Prospects of the Auger Engineering Radio Arraymarko zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Darko Veberič, Marta Trini, Samo Stanič, Ahmed Saleh, Gašper Kukec Mezek, Andrej Filipčič, Johannes Schulz, 2015, published scientific conference contribution Abstract: The Auger Engineering Radio Array (AERA) is an extension of the
Pierre Auger Observatory. It is used to detect radio emission
from extensive air showers in the 30 - 80 MHz frequency band.
A focus of interest is the dependence of the radio emission on
shower parameters such as the energy and the atmospheric depth
of the shower maximum. After three phases of deployment, AERA
now consists of 153 autonomous radio stations with different
spacings, covering an area of about 17 km2. The size, station
spacings, and geographic location at the same site or near other
Auger extensions, are all targeted at cosmic ray energies above
10[sup]17 eV. The array allows us to explore different
technical schemes to measure the radio emission as well as to
cross calibrate our measurements with the established baseline
detectors of the Auger Observatory. We present the most recent
technological developments and selected experimental results
obtained with AERA. Found in: ključnih besedah Summary of found: ...is used to detect radio emission
from extensive air showers in the 30 - 80... Keywords: Pierre Auger Observatory, the Auger Engineering Radio Array (AERA), radio emission from extensive air showers, detector cross-calibration Published: 03.03.2016; Views: 3743; Downloads: 184
Fulltext (2,79 MB) |
10. Report of the Working Group on the Composition of Ultra-High Energy Cosmic Raysmarko zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Darko Veberič, Marta Trini, Samo Stanič, Ahmed Saleh, Gašper Kukec Mezek, Andrej Filipčič, Michael Unger, 2015, published scientific conference contribution Abstract: The atmospheric depth, Xmax, at which the particle number of
an air shower reaches its maximum is a good indicator for the
mass of the primary particle. We present a comparison of the
energy evolution of the mean of Xmax as measured by the
Telescope Array and c Collaborations. After
accounting for the different resolutions, acceptances and
analysis strategies of the two experiments, the two results are
found to be in good agreement within systematic uncertainties. Found in: ključnih besedah Summary of found: ...ory,
Telescope Array,
Ultra-High Energy Cosmic Rays,
elemental composition,
extensive air showers,
the atmospheric depth of the... Keywords: Pierre Auger Observatory, Telescope Array, Ultra-High Energy Cosmic Rays, elemental composition, extensive air showers, the atmospheric depth of the air shower maximum Published: 08.03.2016; Views: 3739; Downloads: 227
Fulltext (329,86 KB) |