59 research outputs found
Embedded Software of the KM3NeT Central Logic Board
The KM3NeT Collaboration is building and operating two deep sea neutrino
telescopes at the bottom of the Mediterranean Sea. The telescopes consist of
latices of photomultiplier tubes housed in pressure-resistant glass spheres,
called digital optical modules and arranged in vertical detection units. The
two main scientific goals are the determination of the neutrino mass ordering
and the discovery and observation of high-energy neutrino sources in the
Universe. Neutrinos are detected via the Cherenkov light, which is induced by
charged particles originated in neutrino interactions. The photomultiplier
tubes convert the Cherenkov light into electrical signals that are acquired and
timestamped by the acquisition electronics. Each optical module houses the
acquisition electronics for collecting and timestamping the photomultiplier
signals with one nanosecond accuracy. Once finished, the two telescopes will
have installed more than six thousand optical acquisition nodes, completing one
of the more complex networks in the world in terms of operation and
synchronization. The embedded software running in the acquisition nodes has
been designed to provide a framework that will operate with different hardware
versions and functionalities. The hardware will not be accessible once in
operation, which complicates the embedded software architecture. The embedded
software provides a set of tools to facilitate remote manageability of the
deployed hardware, including safe reconfiguration of the firmware. This paper
presents the architecture and the techniques, methods and implementation of the
embedded software running in the acquisition nodes of the KM3NeT neutrino
telescopes
The Power Board of the KM3NeT Digital Optical Module: design, upgrade, and production
The KM3NeT Collaboration is building an underwater neutrino observatory at
the bottom of the Mediterranean Sea consisting of two neutrino telescopes, both
composed of a three-dimensional array of light detectors, known as digital
optical modules. Each digital optical module contains a set of 31 three inch
photomultiplier tubes distributed over the surface of a 0.44 m diameter
pressure-resistant glass sphere. The module includes also calibration
instruments and electronics for power, readout and data acquisition. The power
board was developed to supply power to all the elements of the digital optical
module. The design of the power board began in 2013, and several prototypes
were produced and tested. After an exhaustive validation process in various
laboratories within the KM3NeT Collaboration, a mass production batch began,
resulting in the construction of over 1200 power boards so far. These boards
were integrated in the digital optical modules that have already been produced
and deployed, 828 until October 2023. In 2017, an upgrade of the power board,
to increase reliability and efficiency, was initiated. After the validation of
a pre-production series, a production batch of 800 upgraded boards is currently
underway. This paper describes the design, architecture, upgrade, validation,
and production of the power board, including the reliability studies and tests
conducted to ensure the safe operation at the bottom of the Mediterranean Sea
throughout the observatory's lifespa
Prospects for combined analyses of hadronic emission from -ray sources in the Milky Way with CTA and KM3NeT
The Cherenkov Telescope Array and the KM3NeT neutrino telescopes are major
upcoming facilities in the fields of -ray and neutrino astronomy,
respectively. Possible simultaneous production of rays and neutrinos
in astrophysical accelerators of cosmic-ray nuclei motivates a combination of
their data. We assess the potential of a combined analysis of CTA and KM3NeT
data to determine the contribution of hadronic emission processes in known
Galactic -ray emitters, comparing this result to the cases of two
separate analyses. In doing so, we demonstrate the capability of Gammapy, an
open-source software package for the analysis of -ray data, to also
process data from neutrino telescopes. For a selection of prototypical
-ray sources within our Galaxy, we obtain models for primary proton and
electron spectra in the hadronic and leptonic emission scenario, respectively,
by fitting published -ray spectra. Using these models and instrument
response functions for both detectors, we employ the Gammapy package to
generate pseudo data sets, where we assume 200 hours of CTA observations and 10
years of KM3NeT detector operation. We then apply a three-dimensional binned
likelihood analysis to these data sets, separately for each instrument and
jointly for both. We find that the largest benefit of the combined analysis
lies in the possibility of a consistent modelling of the -ray and
neutrino emission. Assuming a purely leptonic scenario as input, we obtain, for
the most favourable source, an average expected 68% credible interval that
constrains the contribution of hadronic processes to the observed -ray
emission to below 15%.Comment: 18 pages, 15 figures. Submitted to journa
Role of fuel additives on reduction of NOX emission from a diesel engine powered by camphor oil biofuel
Influence of Waste Cooking Oil Methyl Ester Biodiesel Blends on the Performance and Emissions of a Diesel Engine
Searches for neutrino counterparts of gravitational waves from the LIGO/Virgo third observing run with KM3NeT
International audienceThe KM3NeT neutrino telescope is currently being deployed at two different sites in the Mediterranean Sea. First searches for astrophysical neutrinos have been performed using data taken with the partial detector configuration already in operation. The paper presents the results of two independent searches for neutrinos from compact binary mergers detected during the third observing run of the LIGO and Virgo gravitational wave interferometers. The first search looks for a global increase in the detector counting rates that could be associated with inverse beta decay events generated by MeV-scale electron anti-neutrinos. The second one focuses on upgoing track-like events mainly induced by muon (anti-)neutrinos in the GeV--TeV energy range. Both searches yield no significant excess for the sources in the gravitational wave catalogs. For each source, upper limits on the neutrino flux and on the total energy emitted in neutrinos in the respective energy ranges have been set. Stacking analyses of binary black hole mergers and neutron star-black hole mergers have also been performed to constrain the characteristic neutrino emission from these categories
Search for Neutrino Emission from GRB 221009A using the KM3NeT ARCA and ORCA detectors
International audienceGamma-ray bursts are promising candidate sources of high-energy astrophysical neutrinos. The recent GRB 221009A event, identified as the brightest gamma-ray burst ever detected, provides a unique opportunity to investigate hadronic emissions involving neutrinos. The KM3NeT undersea neutrino detectors participated in the worldwide follow-up effort triggered by the event, searching for neutrino events. In this letter, we summarize subsequent searches, in a wide energy range from MeV up to a few PeVs. No neutrino events are found in any of the searches performed. Upper limits on the neutrino emission associated with GRB 221009A are computed
Searches for neutrino counterparts of gravitational waves from the LIGO/Virgo third observing run with KM3NeT
International audienceThe KM3NeT neutrino telescope is currently being deployed at two different sites in the Mediterranean Sea. First searches for astrophysical neutrinos have been performed using data taken with the partial detector configuration already in operation. The paper presents the results of two independent searches for neutrinos from compact binary mergers detected during the third observing run of the LIGO and Virgo gravitational wave interferometers. The first search looks for a global increase in the detector counting rates that could be associated with inverse beta decay events generated by MeV-scale electron anti-neutrinos. The second one focuses on upgoing track-like events mainly induced by muon (anti-)neutrinos in the GeV--TeV energy range. Both searches yield no significant excess for the sources in the gravitational wave catalogs. For each source, upper limits on the neutrino flux and on the total energy emitted in neutrinos in the respective energy ranges have been set. Stacking analyses of binary black hole mergers and neutron star-black hole mergers have also been performed to constrain the characteristic neutrino emission from these categories
Differential Sensitivity of the KM3NeT/ARCA detector to a diffuse neutrino flux and to point-like source emission: Exploring the case of the Starburst Galaxies
International audienceKM3NeT/ARCA is a Cherenkov neutrino telescope under construction in the Mediterranean sea, optimised for the detection of astrophysical neutrinos with energies above âŒ1 TeV. In this work, using Monte Carlo simulations including all-flavour neutrinos, the integrated and differential sensitivities for KM3NeT/ARCA are presented considering the case of a diffuse neutrino flux as well as extended and point-like neutrino sources. This analysis is applied to Starburst Galaxies demonstrating that the detector has the capability of tracing TeV neutrinos from these sources. Remarkably, after eight years, a hard power-law spectrum from the nearby Small Magellanic Cloud can be constrained. The sensitivity and discovery potential for NGC 1068 is also evaluated showing that KM3NeT/ARCA will discriminate between different astrophysical components of the measured neutrino flux after 3 years of data taking
Search for Neutrino Emission from GRB 221009A using the KM3NeT ARCA and ORCA detectors
International audienceGamma-ray bursts are promising candidate sources of high-energy astrophysical neutrinos. The recent GRB 221009A event, identified as the brightest gamma-ray burst ever detected, provides a unique opportunity to investigate hadronic emissions involving neutrinos. The KM3NeT undersea neutrino detectors participated in the worldwide follow-up effort triggered by the event, searching for neutrino events. In this letter, we summarize subsequent searches, in a wide energy range from MeV up to a few PeVs. No neutrino events are found in any of the searches performed. Upper limits on the neutrino emission associated with GRB 221009A are computed
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