An official website of the United States government
Abstract Atmospheric neutrinos are one of the most relevant natural neutrino sources that can be exploited to infer properties about cosmic rays and neutrino oscillations. The Jiangmen Underground Neutrino Observatory (JUNO) experiment, a 20 kton liquid scintillator detector with excellent energy resolution is currently under construction in China. JUNO will be able to detect several atmospheric neutrinos per day given the large volume. A study on the JUNO detection and reconstruction capabilities of atmospheric $$\nu _e$$ ν e and $$\nu _\mu $$ ν μ fluxes is presented in this paper. In this study, a sample of atmospheric neutrino Monte Carlo events has been generated, starting from theoretical models, and then processed by the detector simulation. The excellent timing resolution of the 3” PMT light detection system of JUNO detector and the much higher light yield for scintillation over Cherenkov allow to measure the time structure of the scintillation light with very high precision. Since $$\nu _e$$ ν e and $$\nu _\mu $$ ν μ interactions produce a slightly different light pattern, the different time evolution of light allows to discriminate the flavor of primary neutrinos. A probabilistic unfolding method has been used, in order to infer the primary neutrino energy spectrum from the detector experimental observables. The simulated spectrum has been reconstructed between 100 MeV and 10 GeV, showing a great potential of the detector in the atmospheric low energy region.
more »
« less
toise: a framework to describe the performance of high-energy neutrino detectors
Abstract Neutrinos offer a unique window to the distant, high-energy universe. Several next-generation instruments are being designed and proposed to characterize the flux of TeV–EeV neutrinos. The projected physics reach of the detectors is often quantified with simulation studies. However, a complete Monte Carlo estimate of detector performance is costly from a computational perspective, restricting the number of detector configurations considered when designing the instruments. In this paper, we present a new Python-based software framework, toise , which forecasts the performance of a high-energy neutrino detector using parameterizations of the detector performance, such as the effective areas, angular and energy resolutions, etc. The framework can be used to forecast performance of a variety of physics analyses, including sensitivities to diffuse fluxes of neutrinos and sensitivity to both transient and steady state point sources. This parameterized approach reduces the need for extensive simulation studies in order to estimate detector performance, and allows the user to study the influence of single performance metrics, like the angular resolution, in isolation. The framework is designed to allow for multiple detector components, each with different responses and exposure times, and supports paramterization of both optical- and radio-Cherenkov (Askaryan) neutrino telescopes. In the paper, we describe the mathematical concepts behind toise and introduce the reader to the use of the framework.
more »
« less
- Award ID(s):
- 1903885
- PAR ID:
- 10408488
- Date Published:
- Journal Name:
- Journal of Instrumentation
- Volume:
- 17
- Issue:
- 08
- ISSN:
- 1748-0221
- Page Range / eLocation ID:
- T08009
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
The Askaryan Radio Array (ARA) is an ultrahigh energy (UHE, >10^17 eV) neutrino detector designed to observe neutrinos by searching for the radio waves emitted by the relativistic products of neutrino-nucleon interactions in Antarctic ice. In this paper, we present constraints on the diffuse flux of ultrahigh energy neutrinos between 1016 and 1021 eV resulting from a search for neutrinos in two complementary analyses, both analyzing four years of data (2013–2016) from the two deep stations (A2, A3) operating at that time. We place a 90% CL upper limit on the diffuse all flavor neutrino flux at 1018 eV of EF(E)=5.6×10^−16 cm^−2 s^−1 sr^−1. This analysis includes four times the exposure of the previous ARA result and represents approximately 1/5^th the exposure expected from operating ARA until the end of 2022.more » « less
-
Abstract New neutrino interactions beyond the Standard Model (BSM) have been of much interest in not only particle physics but also cosmology and astroparticle physics. We numerically investigate the time delay distribution of astrophysical neutrinos that interact with the cosmic neutrino background. Using the Monte Carlo method, we develop a framework that enables us to simulate the time-dependent energy spectra of high-energy neutrinos that experience even multiple scatterings en route and to handle the sharp increase in the cross section at the resonance energy. As an example, we focus on the case of secret neutrino interactions with a scalar mediator. While we find the excellent agreement between analytical and simulation results for small optical depths, our simulations enable us to study optically thick cases that are not described by the simplest analytic estimates. Our simulations are used to understand effects of cosmological redshifts, neutrino spectra and flavors. The developments will be useful for probing BSM neutrino interactions with not only current neutrino detectors such as IceCube and Super-Kamiokande but also future neutrino detectors such as IceCube-Gen2 and Hyper-Kamiokande.more » « less
-
Abstract Although Cherenkov detectors of high-energy neutrinos in ice and water are often optimized to detect teraelectronvolt–petaelectronvolt neutrinos, they may also be sensitive to transient neutrino sources in the 1–100 GeV energy range. A wide variety of transient sources have been predicted to emit gigaelectronvolt neutrinos. In light of the upcoming IceCube Upgrade, which will extend the IceCube detector’s sensitivity down to a few gigaelectronvolts, as well as improve its angular resolution, we survey a variety of transient-source models and compare their predicted neutrino fluences to detector sensitivities, in particular those of IceCube-DeepCore and the IceCube Upgrade. We consider ranges of neutrino fluence from transients powered by nonrelativistic shocks, such as novae, supernovae, fast blue optical transients, and tidal disruption events. We also consider fast radio bursts and relativistic outflows of high- and low-luminosity gamma-ray bursts. Our study sheds light on the prospects of observing gigaelectronvolt transients with existing and upcoming neutrino facilities.more » « less
-
Neutrinos from a particle collider have never been directly detected. FASER𝜈 at the Large Hadron Collider (LHC) is designed to detect such neutrinos for the first time and study their cross sections at TeV energies—at present, no such measurements are available at such high energies. In 2018, during LHC Run 2, we installed a pilot detector 480-m downstream of the ATLAS interaction point. In this pilot run, proton–proton collision data of 12.2 fb−1 at a center-of-mass energy of 13 TeV were collected. We observed the first candidate vertices, which were consistent with neutrino interactions. A 2.7𝜎 excess of neutrino-like signal above the background was measured. This milestone opens a new avenue for studying neutrinos at the existing and future high-energy colliders. During LHC Run 3, which will commence in 2022, we will deploy an emulsion detector with a target mass of 1.1 tons, coupled with the FASER magnetic spectrometer. This will yield ∼2,000 𝜈𝑒, ∼6,000 𝜈𝜇, and ∼40 𝜈𝜏 interactions in the detector. Herein, we present the status and plan of FASER𝜈 and report neutrino detection in the 2018 data.more » « less
- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1088/1748-0221/17/08/T08009
