698 research outputs found
The IceCube Realtime Alert System
Although high-energy astrophysical neutrinos were discovered in 2013, their origin is still unknown. Aiming for the identification of an electromagnetic counterpart of a rapidly fading source, we have implemented a realtime analysis framework for the IceCube neutrino observatory. Several analyses selecting neutrinos of astrophysical origin are now operating in realtime at the detector site in Antarctica and are producing alerts for the community to enable rapid follow-up observations. The goal of these observations is to locate the astrophysical objects responsible for these neutrino signals. This paper highlights the infrastructure in place both at the South Pole site and at IceCube facilities in the north that have enabled this fast follow-up program to be implemented. Additionally, this paper presents the first realtime analyses to be activated within this framework, highlights their sensitivities to astrophysical neutrinos and background event rates, and presents an outlook for future discoveries
The IceCube Realtime Alert System
Following the detection of high-energy astrophysical neutrinos in 2013, their
origin is still unknown. Aiming for the identification of an electromagnetic
counterpart of a rapidly fading source, we have implemented a realtime analysis
framework for the IceCube neutrino observatory. Several analyses selecting
neutrinos of astrophysical origin are now operating in realtime at the detector
site in Antarctica and are producing alerts to the community to enable rapid
follow-up observations. The goal of these observations is to locate the
astrophysical objects responsible for these neutrino signals. This paper
highlights the infrastructure in place both at the South Pole detector site and
at IceCube facilities in the north that have enabled this fast follow-up
program to be developed. Additionally, this paper presents the first realtime
analyses to be activated within this framework, highlights their sensitivities
to astrophysical neutrinos and background event rates, and presents an outlook
for future discoveries.Comment: 33 pages, 9 figures, Published in Astroparticle Physic
M@TE - Monitoring at TeV Energies
Blazars are extremely variable objects emitting radiation across the
electromagnetic spectrum and showing variability on time scales from minutes to
years. For the understanding of the emission mechanisms, simultaneous
multi-wavelength observations are crucial. Various models for flares predict
simultaneous flux increases in the X-ray and gamma-ray band or more complex
variability patterns, depending on the dominant process responsible for the
gamma-ray emission. Monitoring at TeV energies is providing important
information to distinguish between different models. To study duty cycle and
variability time scales of an object, an unbiased data sample is essential, and
good sensitivity and continuous monitoring are needed to resolve smaller time
scales. A dedicated long-term monitoring program at TeV energies has been
started by the FACT project. Its success clearly illustrated that the usage of
silicon based photo sensors (SIPMs) is ideal for long-term monitoring. They
provide not only an excellent and stable detector performance, but also allow
for observations during bright ambient light minimizing observational gaps and
increasing the instrument's duty cycle. The observation time in a single
longitude is limited to 6 hours. To study typical variability time scales of
few hours to one day, the ultimate goal is 24/7 monitoring with a network of
small telescopes around the globe (DWARF project). The installation of an
Imaging Air Cherenkov Telescope is planned in San Pedro Martir, Mexico. For the
M@TE (Monitoring at TeV energies) telescope, a mount from a previous experiment
is being refurbished to be equipped with a camera using the new generation of
SiPMs. In the presentation, the status of the M@TE project will be reported
outlining the scientific potential, including the possibility to extend
monitoring campaigns to 12 hours by coordinated observations together with
FACT.Comment: 5 pages, 1 figure. Contribution to the 6th International Symposium on
High Energy Gamma-Ray Astronomy (Gamma2016), Heidelberg, Germany. To be
published in the AIP Conference Proceeding
The H.E.S.S. central data acquisition system
The High Energy Stereoscopic System (H.E.S.S.) is a system of Imaging
Atmospheric Cherenkov Telescopes (IACTs) located in the Khomas Highland in
Namibia. It measures cosmic gamma rays of very high energies (VHE; >100 GeV)
using the Earth's atmosphere as a calorimeter. The H.E.S.S. Array entered Phase
II in September 2012 with the inauguration of a fifth telescope that is larger
and more complex than the other four. This paper will give an overview of the
current H.E.S.S. central data acquisition (DAQ) system with particular emphasis
on the upgrades made to integrate the fifth telescope into the array. At first,
the various requirements for the central DAQ are discussed then the general
design principles employed to fulfil these requirements are described. Finally,
the performance, stability and reliability of the H.E.S.S. central DAQ are
presented. One of the major accomplishments is that less than 0.8% of
observation time has been lost due to central DAQ problems since 2009.Comment: 17 pages, 8 figures, published in Astroparticle Physic
Synergies between astroparticle, particle and nuclear physics
One overarching objective of science is to further our understanding of the
universe, from its early stages to its current state and future evolution. This
depends on gaining insight on the universe's most macroscopic components, for
example galaxies and stars, as well as describing its smallest components,
namely elementary particles and nuclei and their interactions. It is clear that
this endeavour requires combined expertise from the fields of astroparticle
physics, particle physics and nuclear physics. Pursuing common scientific
drivers also require mastering challenges related to instrumentation (e.g.
beams and detectors), data acquisition, selection and analysis, and making data
and results available to the broader science communities. Joint work and
recognition of these "foundational" topics will help all communities grow
towards their individual and common scientific goals. The talk corresponding to
this contribution has been presented during the special ECFA session of EPS-HEP
2019 focused on the update of the European Strategy of Particle Physics.Comment: Late submission to the Proceedings of the EPS-HEP 2019 Conference,
Special ECFA session (https://indico.cern.ch/event/577856/sessions/291392
The Astrophysical Multimessenger Observatory Network (AMON)
We summarize the science opportunity, design elements, current and projected partner observatories, and anticipated science returns of the Astrophysical Multimessenger Observatory Network (AMON). AMON will link multiple current and future high-energy, multimessenger, and follow-up observatories together into a single network, enabling near real-time coincidence searches for multimessenger astrophysical transients and their electromagnetic counterparts. Candidate and high-confidence multimessenger transient events will be identified, characterized, and distributed as AMON alerts within the network and to interested external observers, leading to follow-up observations across the electromagnetic spectrum. In this way, AMON aims to evoke the discovery of multimessenger transients from within observatory subthreshold data streams and facilitate the exploitation of these transients for purposes of astronomy and fundamental physics. As a central hub of global multimessenger science, AMON will also enable cross-collaboration analyses of archival datasets in search of rare or exotic astrophysical phenomena
The Dawn of Multi-Messenger Astronomy
The recent discoveries of high-energy astrophysical neutrinos and
gravitational waves have opened new windows of exploration to the Universe.
Combining neutrino observations with measurements of electromagnetic radiation
and cosmic rays promises to unveil the sources responsible for the neutrino
emission and to help solve long-standing problems in astrophysics such as the
origin of cosmic rays. Neutrino observations may also help localize
gravitational-wave sources, and enable the study of their astrophysical
progenitors. In this work we review the current status and future plans for
multi-messenger searches of neutrino sources.Comment: To appear in "Neutrino Astronomy- Current status, future prospects",
Eds. T. Gaisser & A. Karle (World Scientific
Polish grid infrastructure for science and research
Structure, functionality, parameters and organization of the computing Grid
in Poland is described, mainly from the perspective of high-energy particle
physics community, currently its largest consumer and developer. It represents
distributed Tier-2 in the worldwide Grid infrastructure. It also provides
services and resources for data-intensive applications in other sciences.Comment: Proceeedings of IEEE Eurocon 2007, Warsaw, Poland, 9-12 Sep. 2007,
p.44
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