Latest research on searching for fractionally charged particles with DAMPE
POS PROCEEDINGS OF SCIENCE
Published On 2023
The existence of fractionally charged particles (FCP) is foreseen in some extensions to the Standard Model of particle physics, and their detection would be a significant breakthrough. Most of the previous cosmic-rays (CRs) studies are mainly focused on the secondary CRs from the extensive air shower, but there is rarely on-orbit study to search FCP from primary CRs. The DArk Matter Particle Explorer (DAMPE) was launched into space on the 17th December 2015, and it has been working well in space for more than five years with the purpose of measuring CRs and gamma-rays, and as today a large amount of scientific data has been acquired. The FCP is assumed to be a heavy lepton, as a result, the Minimum Ionized Particles (MIPs) are selected. The Geant4 simulations toolkit is used to investigate the signal region and to evaluate selection efficiency of 2/3 FCP in DAMPE. The detailed selection methods are presented and discussed in this work.
Journal
POS PROCEEDINGS OF SCIENCE
Published On
2023
Volume
395
Authors
Huanzhao Liu
Indiana University Bloomington
Position
H-Index(all)
332
H-Index(since 2020)
210
I-10 Index(all)
0
I-10 Index(since 2020)
0
Citation(all)
0
Citation(since 2020)
0
Cited By
0
Research Interests
Experimental Particle Physics
Collider Physics
University Profile Page
Zhiyong Zhang
Northwest University, China
Position
H-Index(all)
46
H-Index(since 2020)
40
I-10 Index(all)
0
I-10 Index(since 2020)
0
Citation(all)
0
Citation(since 2020)
0
Cited By
0
Research Interests
Semiconductor Materials
University Profile Page
Other Articles from authors
Zhiyong Zhang
Northwest University, China
Shanghai Journal of Stomatology
Evaluation of the 5-year clinical restoration effect of implants retained complete overdentures with Locator attachments in 48 patients
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Article DetailsZhiyong Zhang
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Article DetailsZhiyong Zhang
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Article DetailsZhiyong Zhang
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Article DetailsZhiyong Zhang
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Article DetailsZhiyong Zhang
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2024/3
Article DetailsZhiyong Zhang
Northwest University, China
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
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Article DetailsZhiyong Zhang
Northwest University, China
ACTA PHYSICA SINICA
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Article DetailsZhiyong Zhang
Northwest University, China
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Article DetailsZhiyong Zhang
Northwest University, China
Phytotaxa
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Article DetailsZhiyong Zhang
Northwest University, China
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2023/7/25
Article DetailsHuanzhao Liu
Indiana University Bloomington
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Northwest University, China
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Article DetailsZhiyong Zhang
Northwest University, China
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Northwest University, China
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2023
Article DetailsOther articles from POS PROCEEDINGS OF SCIENCE journal
Martin Israel
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POS PROCEEDINGS OF SCIENCE
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Article DetailsKunihito Ioka
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POS PROCEEDINGS OF SCIENCE
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POS PROCEEDINGS OF SCIENCE
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POS PROCEEDINGS OF SCIENCE
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2024
Article DetailsGianmaria Collazuol
Università degli Studi di Padova
POS PROCEEDINGS OF SCIENCE
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2024
Article DetailsGianmaria Collazuol
Università degli Studi di Padova
POS PROCEEDINGS OF SCIENCE
Results from CALorimetric Electron Telescope (CALET) Observations of Gamma-rays on the International Space Station
The CALorimetric Electron Telescope (CALET) cosmic ray detector on the International Space Station (ISS) has been in operation since its launch in 2015. The main instrument, the CALorimeter (CAL), is optimized to observe high-energy electrons up to TeV energies, but its three-storied, composite and thick detector enable us to discriminate gamma rays from overwhelming background of charged cosmic rays. Thus, it is monitoring the gamma ray sky from 1 GeV up to 10 TeV with a field of view of about 2 sr, but the exposure is somewhat non-uniform because of the limitation imposed by the inclination angle (51.6 degree) of the ISS orbit. In this paper we report results from gamma ray observations obtained during its mission for more than seven years with increased statistics compared with previous reports. They include properties of the Galactic diffuse gamma rays, spectra of bright Galactic point sources, and light curves of extragalactic active galactic nuclei, which show good consistencies with Fermi-LAT observations of which energy range overlaps with CALET.
2024
Article DetailsGabriele Bigongiari
Università degli Studi di Siena
POS PROCEEDINGS OF SCIENCE
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2024
Article DetailsJun KATAOKA
Waseda University
POS PROCEEDINGS OF SCIENCE
Flux ratios of primary elements measured by CALET on the International Space Station
The study of flux ratios of cosmic-ray primary elements is of particular interest not only to assess the relative abundance of each element, but also to gain a deeper understanding of their propagation in the galaxy. High energy cosmic ray data are the best candidate for this purpose as convection, nuclear decay, and energy degradation can be neglected during their propagation. CALET on the International Space Station has been measuring the flux of several primary elements from proton to nickel for 7 years to date. In this contribution, the flux ratios of heavy primary elements to lighter primaries will be shown, extending the energy range already investigated by previous measurements.
2024
Article DetailsHenric Krawczynski
Washington University in St. Louis
POS PROCEEDINGS OF SCIENCE
Highlights from the CALET observations for 7.5 years on the International Space Station
The CALorimetric Electron Telescope (CALET) space experiment is a high-energy astroparticle physics mission installed on the International Space Station (ISS). The primary goals of the CALET mission include studying the details of galactic cosmic-ray acceleration and propagation, and searching for possible nearby sources of high-energy electrons and dark matter signatures. The CALET experiment is measuring the flux of cosmic-ray electrons (including positrons) to 20 TeV, gamma-rays to 10 TeV and nuclei with Z=1 to 40 up to 1,000 TeV. The instrument consists of two layers of segmented plastic scintillators for the identification of cosmic-rays via a measurement of their charge (CHD), a 3 radiation length thick tungsten-scintillating fiber imaging calorimeter (IMC) and a 27 radiation length thick lead-tungstate calorimeter (TASC). The instrument was launched on August 19, 2015 to the ISS and installed on the Japanese Experiment Module-Exposed Facility (JEM-EF). Since the start of operations in mid-October, 2015, CALET has been in continuous observation mode over 7.5 years and mainly triggering on high energy (>10 GeV) cosmic-ray showers without any major interruption. The number of triggered events over 10 GeV is nearly 1.86 billion events as of June 30, 2023. Here, we present the highlights of the CALET latest results, including the electron + positron energy spectrum, the spectra of protons and other nuclei, gamma-ray observations, as well as the characterization of on-orbit performance. Some results on the electromagnetic counterpart search for LIGO/Virgo gravitational wave events and the observations of solar modulation and …
2024
Article DetailsJun KATAOKA
Waseda University
POS PROCEEDINGS OF SCIENCE
Results of the Ultra-Heavy Cosmic-Ray Analysis with CALET on the International Space Station
The Calorimetric Electron Telescope (CALET), launched to the ISS in August 2015 and in continuous operation since, measures cosmic-ray (CR) electrons, nuclei, and gamma rays. CALET, with its 27 radiation length deep Total Absorption Calorimeter (TASC), measures particle energy, allowing for the determination of spectra and secondary to primary ratios of the more abundant CR nuclei through 28Ni, while the main charge detector (CHD) can measure Ultra-Heavy (UH) CR nuclei through 40Zr. Previous CALET UHCR analyses used a special high duty cycle (~90%) UH trigger that does not require passage through the TASC and used time- and position-dependent detector response corrections based on 14Si and 26Fe and an angle-dependent geomagnetic cutoff rigidity selection to show abundances of even nuclei in agreement with SuperTIGER and ACE-CRIS. The work shown here further improves upon those results by restricting UH events to those that pass through both the TASC and CHD. While this constraint does reduce the number of events to ~1/6 of the original UH trigger analysis, the loss of statistics is compensated by improvements in event selection from an energy-binned charge determination and minimum deposited energy that substitutes for the previous minimum geomagnetic rigidity selection. The results shown here represent 7 years of observation for the abundances of elements from Z=10 to Z=40 relative to 26Fe and are compared to previous measurements from ACE-CRIS, SuperTIGER, and HEAO-3.
2024
Article DetailsVenelin Kozhuharov
Sofia University St. Kliment Ohridski
POS PROCEEDINGS OF SCIENCE
Recent results from precision measurements at the NA62 experiment
Recent results from precision measurements at the NA62 experiment IRIS IRIS Home Sfoglia Macrotipologie & tipologie Autore Titolo Riviste Serie Settore Scientifico Disciplinare Tipologia ISI-CRUI Afferenza IT Italiano Italiano English English LOGIN 1.IRIS 2.Pubblicazioni 3.02 - Intervento a convegno Akmete, A., Aliberti, R., Ambrosino, F., Ammendola, R., Angelucci, B., Antonelli, A., et al. (2024). Recent results from precision measurements at the NA62 experiment. ??????? it.cilea.surplus.oa.citation.tipologie.CitationProceedings.prensentedAt ??????? The European Physical Society Conference on High Energy Physics (EPS-HEP2023), Hamburg [10.22323/1.449.0336]. Recent results from precision measurements at the NA62 experiment V. Bonaiuto; F. Sargeni; 2024-01-01 Scheda breve Scheda completa Scheda completa (DC) Nome del convegno The European Physical Society Conference on High Energy …
2024
Article DetailsGabriele Bigongiari
Università degli Studi di Siena
POS PROCEEDINGS OF SCIENCE
CALET Search for electromagnetic counterparts of gravitational waves in O4
The latest LIGO/Virgo/KAGRA observing run (O4) started on May 24 in 2023. Many ground and space instruments have participated in follow-up observation and search for electromagnetic counterparts of gravitational waves. Calorimetric Electron Telescope (CALET) on the Interna- tional Space Station has also searched for electromagnetic counterparts since the observation started in October 2015. Although CALET is a payload for direct measurement of high-energy cosmic rays, CALET has the capability to observe high-energy gamma-rays above 1 GeV with the Calorimeter (CAL) and X-rays / gamma rays in the energy range from 7 keV to 20 MeV with the CALET Gamma-ray Burst Monitor (CGBM). We searched for electromagnetic counterparts of gravitational wave events in the last LIGO/Virgo observing run (O3). Although no candidate was found in CALET data in O3, CAL and CGBM estimated upper limits of gamma-ray / X-ray flux for the gravitational waves in O3. We have been searching for electromagnetic counterparts of gravitational waves in O4 with improved and automated analysis pipelines to deal with many events with high event rates. As of the end of June 2023, the LIGO/Virgo/KAGRA collaboration reported 169 events via the GCN/LVC NOTICE, and 15 of 169 events were reported to GCN Circulars as significant events. Although CGBM and CAL searched for signals associated with the significant events, no candidates were found around the event time of the significant events. We obtained CAL upper limits for eight significant events of which localization high probability region overlapped with the CAL field of view.
2024
Article DetailsKunihito Ioka
Kyoto University
POS PROCEEDINGS OF SCIENCE
Highlights from the CALET observations for 7.5 years on the International Space Station
The CALorimetric Electron Telescope (CALET) space experiment is a high-energy astroparticle physics mission installed on the International Space Station (ISS). The primary goals of the CALET mission include studying the details of galactic cosmic-ray acceleration and propagation, and searching for possible nearby sources of high-energy electrons and dark matter signatures. The CALET experiment is measuring the flux of cosmic-ray electrons (including positrons) to 20 TeV, gamma-rays to 10 TeV and nuclei with Z=1 to 40 up to 1,000 TeV. The instrument consists of two layers of segmented plastic scintillators for the identification of cosmic-rays via a measurement of their charge (CHD), a 3 radiation length thick tungsten-scintillating fiber imaging calorimeter (IMC) and a 27 radiation length thick lead-tungstate calorimeter (TASC). The instrument was launched on August 19, 2015 to the ISS and installed on the Japanese Experiment Module-Exposed Facility (JEM-EF). Since the start of operations in mid-October, 2015, CALET has been in continuous observation mode over 7.5 years and mainly triggering on high energy (>10 GeV) cosmic-ray showers without any major interruption. The number of triggered events over 10 GeV is nearly 1.86 billion events as of June 30, 2023. Here, we present the highlights of the CALET latest results, including the electron + positron energy spectrum, the spectra of protons and other nuclei, gamma-ray observations, as well as the characterization of on-orbit performance. Some results on the electromagnetic counterpart search for LIGO/Virgo gravitational wave events and the observations of solar modulation and …
2024
Article DetailsHenric Krawczynski
Washington University in St. Louis
POS PROCEEDINGS OF SCIENCE
The cosmic-ray electron and positron spectrum measured with CALET on the International Space Station
The CALorimetric Electron Telescope (CALET) has been collecting data on the International Space Station for more than seven years since October 2015. CALET is an all-calorimetric instrument with a total vertical thickness of 30 radiation lengths and fine imaging capability, optimized for the measurement of the electron and positron (all-electron) spectrum well into the TeV energy region. The observed event statistics have increased more than three times since its last publication about the all-electron spectrum to 4.8 TeV in 2018. Based on Monte Carlo simulations, the data analysis effectively rejects background protons, resulting in less than 10% contamination up to the TeV region. The expected systematic errors are investigated. The significance of the cutoff at the TeV region in the energy spectrum, which is expected as a result of radiation loss during propagation, has increased to over 6 sigma. By observing the detailed structure in the TeV region of the energy spectrum, we will investigate on the presence of possible nearby cosmic-ray sources. In this paper, we will present the updated all-electron spectrum, and briefly discuss its interpretations.
2024
Article DetailsValeria Fascianelli
Columbia University in the City of New York
POS PROCEEDINGS OF SCIENCE
Searches for LF/LN violation and hidden sectors in kaon decays at the NA62 experiment
Searches for LF/LN violation and hidden sectors in kaon decays at the NA62 experiment IRIS IRIS Home Sfoglia Macrotipologie & tipologie Autore Titolo Riviste Serie Settore Scientifico Disciplinare Tipologia ISI-CRUI Afferenza IT Italiano Italiano English English LOGIN 1.IRIS 2.Pubblicazioni 3.02 - Intervento a convegno Akmete, A., Aliberti, R., Ambrosino, F., Ammendola, R., Angelucci, B., Antonelli, A., et al. (2024). Searches for LF/LN violation and hidden sectors in kaon decays at the NA62 experiment. ??????? it.cilea.surplus.oa.citation.tipologie.CitationProceedings.prensentedAt ??????? The European Physical Society Conference on High Energy Physics (EPS-HEP2023), Hamburg, Germany [10.22323/1.449.0335]. Searches for LF/LN violation and hidden sectors in kaon decays at the NA62 experiment V. Bonaiuto; F. Sargeni; 2024-01-01 Scheda breve Scheda completa Scheda completa (DC) Nome del …
2024
Article DetailsKunihito Ioka
Kyoto University
POS PROCEEDINGS OF SCIENCE
The cosmic-ray electron and positron spectrum measured with CALET on the International Space Station
The CALorimetric Electron Telescope (CALET) has been collecting data on the International Space Station for more than seven years since October 2015. CALET is an all-calorimetric instrument with a total vertical thickness of 30 radiation lengths and fine imaging capability, optimized for the measurement of the electron and positron (all-electron) spectrum well into the TeV energy region. The observed event statistics have increased more than three times since its last publication about the all-electron spectrum to 4.8 TeV in 2018. Based on Monte Carlo simulations, the data analysis effectively rejects background protons, resulting in less than 10% contamination up to the TeV region. The expected systematic errors are investigated. The significance of the cutoff at the TeV region in the energy spectrum, which is expected as a result of radiation loss during propagation, has increased to over 6 sigma. By observing the detailed structure in the TeV region of the energy spectrum, we will investigate on the presence of possible nearby cosmic-ray sources. In this paper, we will present the updated all-electron spectrum, and briefly discuss its interpretations.
2024
Article Details