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141.
ISS-CREAM flight operation
D. Angelaszek, K. C. Kim, Y. Amarea, N. Anthony, G. H. Choi, M. Chung, M. Copley, L. Derome, L. Eraud, C. Falana, Jon Paul Lundquist, 2019, objavljeni znanstveni prispevek na konferenci

Opis: The Cosmic Ray Energetics And Mass experiment for the International Space Station (ISS-CREAM) is designed and built to measure the elemental energy spectra of cosmic-ray particles (1 ≤ Z ≤ 26) and electrons. It measures the energy of incident cosmic rays from 10^12 to 10^15 eV. ISS-CREAM was launched and deployed to the ISS in August 2017. The Science Operations Center (SOC) at the University of Maryland has been operating the payload on the International Space Station (ISS) in coordination with the Payload Operations Integration Center (POIC) at NASA’s Marshall Space Flight Center. The SOC has been responsible for sending commands to and receiving data from the Science Flight Computer (SFC) on board ISS-CREAM. The ISS-CREAM data taking program interfaces with the POIC using the Telescience Resources Kit through the Software Toolkit for Ethernet Lab-Like Architecture developed by the Boeing Company. The command uplink and data downlink have been through the Track-ing and Data Relay Satellite System. We present the ISS-CREAM flight operations including ISS communications, SFC performance, etc.
Najdeno v: ključnih besedah
Povzetek najdenega: ...The Cosmic Ray Energetics And Mass experiment for the... ...It measures the energy of incident cosmic rays from 10^12 to 10^15 eV. ISS-CREAM was...
Ključne besede: instrumentations, high energy cosmic rays, particle detectors
Objavljeno: 08.02.2021; Ogledov: 1004; Prenosov: 0
.pdf Polno besedilo (1,19 MB)

142.
On-orbit performance of the ISS-CREAM calorimeter
D. Angelaszek, K. C. Kim, Y. Amarea, N. Anthony, G. H. Choi, M. Chung, M. Copley, L. Derome, L. Eraud, C. Falana, Jon Paul Lundquist, 2019, objavljeni znanstveni prispevek na konferenci

Opis: Cosmic Ray Energetics And Mass for the International Space Station (ISS-CREAM) experiment is designed to study the composition and energy spectra of cosmic-ray particles from 10^12 to 10^15 eV. ISS-CREAM was launched and deployed to the ISS in August 2017. The ISS-CREAM payload employs a Silicon Charge Detector for charge measurements, Top and Bottom Counting Detector for electron-hadron separation and a low-energy trigger, a Boronated Scintillator Detector for additional electron-hadron separation, and a Calorimeter (CAL) for en-ergy measurements and a high-energy trigger. The CAL is constructed of 20 layers of tungsten plates interleaved with scintillating fiber ribbons read out by hybrid-photodiodes (HPDs) and densified carbon targets. Each CAL layer is made of 3.5 mm (1 X_0) thick tungsten plates alter-nating with fifty 0.5 mm thick and 1 cm wide scintillating fiber ribbons. Consecutive layers of fiber ribbons are installed orthogonal to each other. Energy deposition in the CAL determines the particle energy and provides tracking information to determine which segment(s) of the charge detectors to use for the charge measurement. Tracking for showers is accomplished by extrapolating each shower axis back to the charge detectors. The performance of the ISS-CREAM CAL during flight is presented.
Najdeno v: ključnih besedah
Povzetek najdenega: ... Cosmic Ray Energetics And Mass for the International... ...instrumentations, high energy cosmic rays, particle detectors...
Ključne besede: instrumentations, high energy cosmic rays, particle detectors
Objavljeno: 08.02.2021; Ogledov: 976; Prenosov: 0
.pdf Polno besedilo (916,46 KB)

143.
e/p separation study using the ISS-CREAM top and bottom counting detectors
Y. Amarea, D. Angelaszek, S. C. Kang, N. Anthony, G. H. Choi, M. Chung, M. Copley, L. Derome, L. Eraud, C. Falana, Jon Paul Lundquist, 2019, objavljeni znanstveni prispevek na konferenci

Opis: Cosmic Ray Energetics And Mass for the International Space Station (ISS-CREAM) is an experiment for studying the origin, acceleration, and propagation mechanisms of high-energy cosmic rays. The ISS-CREAM instrument was launched on the 14th of August 2017 to the ISS aboard the SpaceX-12 Dragon spacecraft. The Top and Bottom Counting Detectors (TCD/BCD) are parts of the ISS-CREAM instrument and designed for studying electron and gamma-ray physics. The TCD/BCD each consist of an array of 20 × 20 photodiodes on a plastic scintillator. The TCD/BCD can separate electrons from protons by using the difference between the shapes of electromagnetic and hadronic showers in the high energy region. The Boosted Decision Tree (BDT) method, which is a deep learning method, is used in this separation study. We will present results of the electron/proton separation study and rejection power in various energy ranges.
Najdeno v: ključnih besedah
Povzetek najdenega: ... Cosmic Ray Energetics And Mass for the International... ...acceleration, and propagation mechanisms of high-energy cosmic rays. The ISS-CREAM instrument was launched on the...
Ključne besede: instrumentations, high energy cosmic rays, particle detectors, composition
Objavljeno: 08.02.2021; Ogledov: 1016; Prenosov: 0
.pdf Polno besedilo (2,14 MB)

144.
Calibration of the underground muon detector of the Pierre Auger Observatory
Lukas Zehrer, Marko Zavrtanik, Danilo Zavrtanik, Serguei Vorobiov, Marta Trini, Samo Stanič, Jon Paul Lundquist, Andrej Filipčič, A. Aab, 2021, izvirni znanstveni članek

Opis: To obtain direct measurements of the muon content of extensive air showers with energy above 10[sup]16.5 eV, the Pierre Auger Observatory is currently being equipped with an underground muon detector (UMD), consisting of 219 10 m[sup]2-modules, each segmented into 64 scintillators coupled to silicon photomultipliers (SiPMs). Direct access to the shower muon content allows for the study of both of the composition of primary cosmic rays and of high-energy hadronic interactions in the forward direction. As the muon density can vary between tens of muons per m[sup]2 close to the intersection of the shower axis with the ground to much less than one per m[sup]2 when far away, the necessary broad dynamic range is achieved by the simultaneous implementation of two acquisition modes in the read-out electronics: the binary mode, tuned to count single muons, and the ADC mode, suited to measure a high number of them. In this work, we present the end-to-end calibration of the muon detector modules: first, the SiPMs are calibrated by means of the binary channel, and then, the ADC channel is calibrated using atmospheric muons, detected in parallel to the shower data acquisition. The laboratory and field measurements performed to develop the implementation of the full calibration chain of both binary and ADC channels are presented and discussed. The calibration procedure is reliable to work with the high amount of channels in the UMD, which will be operated continuously, in changing environmental conditions, for several years.
Najdeno v: ključnih besedah
Povzetek najdenega: ...of both of the composition of primary cosmic rays and of high-energy hadronic interactions in...
Ključne besede: ultra-high energy cosmic rays, extensive air showers (EAS), EAS muonic component, Pierre Auger Observatory, underground muon detector, detector calibration
Objavljeno: 14.04.2021; Ogledov: 1053; Prenosov: 67
URL Polno besedilo (0,00 KB)
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145.
146.
Extrapolating FR-0 radio galaxy source properties from propagation of multi-messenger ultra-high energy cosmic rays
Chiara Righi, Giacomo Bonnoli, Fabrizio Tavecchio, Paolo Da Vela, Anita Reimer, Margot Boughelilba, Serguei Vorobiov, Lukas Merten, Jon Paul Lundquist, 2021, objavljeni znanstveni prispevek na konferenci

Opis: Recently, it has been shown that relatively low luminosity Fanaroff-Riley type 0 (FR-0) radio galaxies are a good candidate source class for a predominant fraction of cosmic rays (CR) accelerated to ultra-high energies (UHE, E>10[sup]18 eV). FR-0s can potentially provide a significant fraction of the UHECR energy density as they are much more numerous in the local universe than more energetic radio galaxies such as FR-1s or FR-2s (up to a factor of ∼5 with z≤0.05 compared to FR-1s). In the present work, UHECR mass composition and energy spectra at the FR-0 sources are estimated by fitting simulation results to the published Pierre Auger Observatory data. This fitting is done using a simulated isotropic sky distribution extrapolated from the measured FR-0 galaxy properties and propagating CRs in plausible extragalactic magnetic field configurations using the CRPropa3 framework. In addition, we present estimates of the fluxes of secondary photons and neutrinos created in UHECR interactions with cosmic photon backgrounds during CR propagation. With this approach, we aim to investigate the properties of the sources with the help of observational multi-messenger data.
Najdeno v: ključnih besedah
Ključne besede: jetted active galaxies, FR-0 radiogalaxies, ultra-high energy cosmic rays, extragalactic magnetic fields, UHECR propagation, UHECR interactions, cosmogenic photons, cosmogenic neutrinos
Objavljeno: 16.08.2021; Ogledov: 611; Prenosov: 0
.pdf Polno besedilo (2,04 MB)

147.
FR-0 jetted active galaxies
Chiara Righi, Jon Paul Lundquist, Giacomo Bonnoli, Fabrizio Tavecchio, Serguei Vorobiov, Paolo Da Vela, Anita Reimer, Margot Boughelilba, Lukas Merten, 2021, objavljeni znanstveni prispevek na konferenci

Opis: Fanaroff-Riley (FR) 0 radio galaxies form a low-luminosity extension to the well-established ultra-high-energy cosmic-ray (UHECR) candidate accelerators FR-1 and FR-2 galaxies. Their much higher number density — up to a factor five times more numerous than FR-1 with z ≤ 0.05 — makes them good candidate sources for an isotropic contribution to the observed UHECR flux. Here, the acceleration and survival of UHECR in prevailing conditions of the FR-0 environment are discussed. First, an average spectral energy distribution (SED) is compiled based on the FR0CAT. These photon fields, composed of a jet and a host galaxy component, form a minimal target photon field for the UHECR, which will suffer from electromagnetic pair production, photo-disintegration, photo-meson production losses, and synchrotron radiation. The two most promising acceleration scenarios based on Fermi-I order and gradual shear acceleration are discussed as well as different escape scenarios. When an efficient acceleration mechanism precedes gradual shear acceleration, e.g., Fermi-I orothers, FR-0 galaxies are likely UHECR accelerators. Gradual shear acceleration requires a jet Lorentz factor of Gamma>1.6, to be faster than the corresponding escape. In less optimistic models, a contribution to the cosmic-ray flux between the knee and ankle is expected to be relatively independent of the realized turbulence and acceleration.
Najdeno v: ključnih besedah
Povzetek najdenega: ...a low-luminosity extension to the well-established ultra-high-energy cosmic-ray (UHECR) candidate accelerators FR-1 and FR-2 galaxies.... ...active galaxies, FR-0 radiogalaxies, ultra-high energy cosmic rays, cosmic ray acceleration, cosmic ray energy losses...
Ključne besede: jetted active galaxies, FR-0 radiogalaxies, ultra-high energy cosmic rays, cosmic ray acceleration, cosmic ray energy losses
Objavljeno: 16.08.2021; Ogledov: 563; Prenosov: 0
.pdf Polno besedilo (1,13 MB)

148.
Application of machine learning techniques for cosmic ray event classification and implementation of a real-time ultra-high energy photon search with the surface detector of the Pierre Auger Observatory
Lukas Zehrer, 2021, doktorska disertacija

Opis: Despite their discovery already more than a century ago, Cosmic Rays (CRs) still did not divulge all their properties yet. Theories about the origin of ultra-high energy (UHE, > 10^18 eV) CRs predict accompanying primary photons. The existence of UHE photons can be investigated with the world’s largest ground-based experiment for detection of CR-induced extensive air showers (EAS), the Pierre Auger Observatory, which offers an unprecedented exposure to rare UHE cosmic particles. The discovery of photons in the UHE regime would open a new observational window to the Universe, improve our understanding of the origin of CRs, and potentially uncloak new physics beyond the standard model. The novelty of the presented work is the development of a "real-time" photon candidate event stream to a global network of observatories, the Astrophysical Multimessenger Observatory Network (AMON). The stream classifies CR events observed by the Auger surface detector (SD) array as regards their probability to be photon nominees, by feeding to advanced machine learning (ML) methods observational air shower parameters of individual CR events combined in a multivariate analysis (MVA). The described straightforward classification procedure further increases the Pierre Auger Observatory’s endeavour to contribute to the global effort of multi-messenger (MM) studies of the highest energy astrophysical phenomena, by supplying AMON partner observatories the possibility to follow-up detected UHE events, live or in their archival data.
Najdeno v: ključnih besedah
Povzetek najdenega: ...already more than a century ago, Cosmic Rays (CRs) still did not divulge all their...
Ključne besede: astroparticle physics, ultra-high energy cosmic rays, ultra-high energy photons, extensive air showers, Pierre Auger Observatory, multi-messenger, AMON, machine learning, multivariate analysis, dissertations
Objavljeno: 27.10.2021; Ogledov: 778; Prenosov: 29
URL Polno besedilo (0,00 KB)
Gradivo ima več datotek! Več...

149.
Testing effects of Lorentz invariance violation in the propagation of astroparticles with the Pierre Auger Observatory
Marko Zavrtanik, Danilo Zavrtanik, Serguei Vorobiov, Samo Stanič, Jon Paul Lundquist, Andrej Filipčič, P. Abreu, Lukas Zehrer, 2022, izvirni znanstveni članek

Najdeno v: ključnih besedah
Povzetek najdenega: ... cosmic ray experiments, ultra high energy, cosmic rays,...
Ključne besede: cosmic ray experiments, ultra high energy, cosmic rays, physics of the early universe, Pierre Auger Observatory, Lorentz invariance violation effects
Objavljeno: 18.01.2022; Ogledov: 378; Prenosov: 9
URL Polno besedilo (0,00 KB)
Gradivo ima več datotek! Več...

150.
Multi-messenger studies with the Pierre Auger Observatory
Lukas Zehrer, Andrej Filipčič, Gašper Kukec Mezek, Jon Paul Lundquist, Samo Stanič, Marta Trini, Serguei Vorobiov, Marko Zavrtanik, Danilo Zavrtanik, 2021, objavljeni znanstveni prispevek na konferenci

Opis: Over the past decade the multi-messenger astrophysics has emerged as a distinct discipline, providing unique insights into the properties of high-energy phenomena in the Universe. The Pierre Auger Observatory, located in Malargüe, Argentina, is the world’s largest cosmic ray detector sensitive to photons, neutrinos, and hadrons at ultra-high energies. Using its data, stringent limits on photon and neutrino fluxes at EeV energies have been obtained. The collaboration uses the excellent angular resolution and the neutrino identification capabilities of the Observatory for follow-up studies of events detected in gravitational waves or other messengers, through cooperation with global multi-messenger networks. We present a science motivation together with an overview of the multi-messenger capabilities and results of the Pierre Auger Observatory.
Najdeno v: ključnih besedah
Povzetek najdenega: ...in Malargüe, Argentina, is the world’s largest cosmic ray detector sensitive to photons, neutrinos, and hadrons... ...high-energy cosmic phenomena, multi-messenger astrophysical studies, cosmic rays, gamma-rays, neutrinos, Pierre Auger Observatory...
Ključne besede: high-energy cosmic phenomena, multi-messenger astrophysical studies, cosmic rays, gamma-rays, neutrinos, Pierre Auger Observatory
Objavljeno: 06.05.2022; Ogledov: 136; Prenosov: 0
.pdf Polno besedilo (1,06 MB)

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