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Author KM3NeT Collaboration (Aiello, S. et al); Alves Garre, S.; Calvo, D.; Carretero, V.; Colomer, M.; Gozzini, S.R.; Hernandez-Rey, J.J.; Khan Chowdhury, N.R.; Lazo, A.; Palacios Gonzalez, J.; Pieterse, C.; Real, D.; Salesa Greus, F.; Sanchez Losa, A.; Zornoza, J.D.; Zuñiga, J.
Title Nanobeacon: A time calibration device for the KM3NeT neutrino telescope Type Journal Article
Year 2022 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 1040 Issue Pages 167132 - 13pp
Keywords Time calibration; Instrumentation; Neutrino telescopes
Abstract The KM3NeT Collaboration is currently constructing a multi-site high-energy neutrino telescope in the Mediterranean Sea consisting of matrices of pressure-resistant glass spheres, each holding a set of 31 small-area photomultipliers. The main goals of the telescope are the observation of neutrino sources in the Universe and the measurement of the neutrino oscillation parameters with atmospheric neutrinos. A relative time synchronisation between photomultipliers of the nanosecond order needed to guarantee the required angular resolution of the detector. Due to the large detector volumes to be instrumented by KM3NeT, a cost reduction of the different systems is a priority. To this end, the inexpensive Nanobeacon has been designed and developed by the KM3NeT Collaboration to be used for detector time-calibration studies. At present, more than 600 & nbsp;Nanobeacons have been already produced. The characterisation of the optical pulse and the wavelength emission profile of the devices is critical for the time calibration. The optical pulse rise time has been quantified as less than 3 ns, while the Full Width Half Maximum is less than 6 ns. The wavelength drift, due to a variation of the supply voltage, has also been qualified as lower than 10 nm for the full range of the Nanobeacon. In this paper, more details about the main features of the Nanobeacon design, production and operation, together with the main properties of the light pulse generated are described.
Address [Aiello, S.; Bruno, R.; Leonora, E.; Longhitano, F.; Randazzo, N.] Ist Nazl Fis Nucl, Sez Catania, Via Santa Sofia 64, I-95123 Catania, Italy, Email: sagreus@ific.uv.es;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN (up) Medium
Area Expedition Conference
Notes WOS:000841467100009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5342
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Author HAWC Collaboration (Albert, A. et al); Salesa Greus, F.
Title Constraints on the Very High Energy Gamma-Ray Emission from Short GRBs with HAWC Type Journal Article
Year 2022 Publication Astrophysical Journal Abbreviated Journal Astrophys. J.
Volume 936 Issue 2 Pages 126 - 14pp
Keywords
Abstract Many gamma-ray bursts (GRBs) have been observed from radio wavelengths, and a few at very high energies (VHEs, >100 GeV). The High Altitude Water Cherenkov (HAWC) gamma-ray observatory is well suited to study transient phenomena at VHEs owing to its large field of view and duty cycle. These features allow for searches of VHE emission and can probe different model assumptions of duration and spectra. In this paper, we use data collected by HAWC between 2014 December and 2020 May to search for emission in the energy range from 80 to 800 GeV coming from a sample of 47 short GRBs that triggered the Fermi, Swift, and Konus satellites during this period. This analysis is optimized to search for delayed and extended VHE emission within the first 20 s of each burst. We find no evidence of VHE emission, either simultaneous or delayed, with respect to the prompt emission. Upper limits (90% confidence level) derived on the GRB fluence are used to constrain the synchrotron self-Compton forward-shock model. Constraints for the interstellar density as low as 10(-2) cm(-3) are obtained when assuming z = 0.3 for bursts with the highest keV fluences such as GRB 170206A and GRB 181222841. Such a low density makes observing VHE emission mainly from the fast-cooling regime challenging.
Address [Albert, A.; Dingus, B. L.; Durocher, M.; Harding, J. P.; Zhou, H.] Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA, Email: nifraija@astro.unam.mx;
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-637x ISBN (up) Medium
Area Expedition Conference
Notes WOS:000852139800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5354
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Author HAWC Collaboration (Alfaro, R. et al); Salesa Greus, F.
Title Gamma/hadron separation with the HAWC observatory Type Journal Article
Year 2022 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 1039 Issue Pages 166984 - 13pp
Keywords High energy; Crab Nebula; G/H separation; Machine Learning
Abstract The High Altitude Water Cherenkov (HAWC) gamma-ray observatory observes atmospheric showers produced by incident gamma rays and cosmic rays with energy from 300 GeV to more than 100 TeV. A crucial phase in analyzing gamma-ray sources using ground-based gamma-ray detectors like HAWC is to identify the showers produced by gamma rays or hadrons. The HAWC observatory records roughly 25,000 events per second, with hadrons representing the vast majority (> 99.9%) of these events. The standard gamma/hadron separation technique in HAWC uses a simple rectangular cut involving only two parameters. This work describes the implementation of more sophisticated gamma/hadron separation techniques, via machine learning methods (boosted decision trees and neural networks), and summarizes the resulting improvements in gamma/hadron separation obtained in HAWC.
Address [Alfaro, R.; Angeles Camacho, J. R.; Avila Rojas, D.; Belmont-Moreno, E.; Espinoza, C.; Garcia, D.; Hernandez, S.; Leon Vargas, H.; Sandoval, A.; Serna-Franco, J.] Univ Nacl Autonoma Mexico, Inst Fis, Mexico City, DF, Mexico, Email: tcapistran@astro.unam.mx;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN (up) Medium
Area Expedition Conference
Notes WOS:000861747900006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5371
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Author Real, D.; Calvo, D.; Diaz, A.; Salesa Greus, F.; Sanchez Losa, A.
Title A Narrow Optical Pulse Emitter Based on LED: NOPELED Type Journal Article
Year 2022 Publication Sensors Abbreviated Journal Sensors
Volume 22 Issue 19 Pages 7683 - 15pp
Keywords short optical pulse; optical instrumentation
Abstract Light sources emitting short pulses are needed in many particle physics experiments using optical sensors as they can replicate the light produced by the particles being detected and are also an important calibration and test element. This work presents NOPELED, a light source based on LEDs emitting short optical pulses with typical rise times of less than 3 ns and Full Width at Half Maximum lower than 7 ns. The emission wavelength depends on the model of LED used. Several LED models have been characterized in the range from 405 to 532 nm, although NOPELED can work with LED emitting wavelengths outside of that region. While the wavelength is fixed for a given LED model, the intensity and the frequency of the optical pulse can be controlled. NOPELED, which also has low cost and simple operation, can be operated remotely, making it appropriate for either different physics experiments needing in-place light sources such as astrophysical neutrino detectors using photo-multipliers or positron emission tomography devices using scintillation counters, or, beyond physics, applications needing short pulses of light such as protein fluorescence or chemodetection of heavy metals.
Address [Real, Diego; Calvo, David; Salesa Greus, Francisco; Sanchez Losa, Agustin] Univ Valencia, IFIC Inst Fis Corpuscular, CSIC, C Catedrat Jose Beltran 2, Paterna 46980, Spain, Email: real@ific.uv.es;
Corporate Author Thesis
Publisher Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN (up) Medium
Area Expedition Conference
Notes WOS:000867935300001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5381
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Author HAWC Collaboration (Alfaro, R. et al); Salesa Greus, F.
Title Validation of standardized data formats and tools for ground-level particle-based gamma-ray observatories Type Journal Article
Year 2022 Publication Astronomy & Astrophysics Abbreviated Journal Astron. Astrophys.
Volume 667 Issue Pages A36 - 12pp
Keywords methods; data analysis; gamma rays; general
Abstract Context. Ground-based gamma-ray astronomy is still a rather young field of research, with strong historical connections to particle physics. This is why most observations are conducted by experiments with proprietary data and analysis software, as is usual in the particle physics field. However, in recent years, this paradigm has been slowly shifting toward the development and use of open-source data formats and tools, driven by upcoming observatories such as the Cherenkov Telescope Array (CTA). In this context, a community-driven, shared data format (the gamma-astro-data-format, or GADF) and analysis tools such as Gammapy and ctools have been developed. So far, these efforts have been led by the Imaging Atmospheric Cherenkov Telescope community, leaving out other types of ground-based gamma-ray instruments. Aims. We aim to show that the data from ground particle arrays, such as the High-Altitude Water Cherenkov (HAWC) observatory, are also compatible with the GADF and can thus be fully analyzed using the related tools, in this case, Gammapy. Methods. We reproduced several published HAWC results using Gammapy and data products compliant with GADF standard. We also illustrate the capabilities of the shared format and tools by producing a joint fit of the Crab spectrum including data from six different gamma-ray experiments. Results. We find excellent agreement with the reference results, a powerful confirmation of both the published results and the tools involved. Conclusions. The data from particle detector arrays such as the HAWC observatory can be adapted to the GADF and thus analyzed with Gammapy. A common data format and shared analysis tools allow multi-instrument joint analysis and effective data sharing. To emphasize this, a sample of Crab nebula event lists is made public with this paper. Because of the complementary nature of pointing and wide-field instruments, this synergy will be distinctly beneficial for the joint scientific exploitation of future observatories such as the Southern Wide-field Gamma-ray Observatory and CTA.
Address [Albert, A.; Durocher, M.; Harding, J. P.] Los Alamos Natl Lab, Phys Div, Los Alamos, NM USA, Email: laura.olivera-nieto@mpi-hd.mpg.de
Corporate Author Thesis
Publisher Edp Sciences S A Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6361 ISBN (up) Medium
Area Expedition Conference
Notes WOS:000879223700008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5408
Permanent link to this record