Abstract
In the standard picture of Galactic cosmic rays, a diffuse flux of high-energy gamma rays and neutrinos is produced from inelastic collisions of cosmic-ray nuclei with the interstellar gas. ...The neutrino flux is a guaranteed signal for high-energy neutrino observatories such as IceCube but has not been found yet. Experimental searches for this flux constitute an important test of the standard picture of Galactic cosmic rays. Both observation and nonobservation would allow important implications for the physics of cosmic-ray acceleration and transport. We present
CRINGE
, a new model of Galactic diffuse high-energy gamma rays and neutrinos, fitted to recent cosmic-ray data from AMS-02, DAMPE, IceTop, as well as KASCADE. We quantify the uncertainties for the predicted emission from the cosmic-ray model but also from the choice of source distribution, gas maps, and cross sections. We consider the possibility of a contribution from unresolved sources. Our model predictions exhibit significant deviations from older models. Our fiducial model is available at
https://doi.org/10.5281/zenodo.7859442
.
NuCraft (nucraft.hepforge.org) is an open-source Python project that calculates neutrino oscillation probabilities for neutrinos from cosmic-ray interactions in the atmosphere for their propagation ...through Earth. The solution is obtained by numerically solving the Schrödinger equation. The code supports arbitrary numbers of neutrino flavors including additional sterile neutrinos, CP violation, arbitrary mass hierarchies, matter effects with a configurable continuous Earth model, and takes into account the production height distribution of neutrinos in the Earth’s atmosphere.
Program title: nuCraft
Catalogue identifier: AEXK_v1_0
Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEXK_v1_0.html
Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland
Licensing provisions: Revised BSD License
No. of lines in distributed program, including test data, etc.: 3017
No. of bytes in distributed program, including test data, etc.: 467122
Distribution format: tar.gz
Programming language: Python.
Computer: IA32/x86-64 compatible.
Operating system: All that are supported by SciPy, e.g., Linux, Windows, OS X.
RAM: 134217728 bytes
Classification: 1.1, 11.1, 11.6.
External routines: NumPy (1.5.1 or newer), SciPy (0.8.0 or newer)
Nature of problem:
Calculation of oscillation probabilities of neutrinos that originate in cosmic-ray interactions in the Earth’s atmosphere and propagate through the Earth, for realistic Earth and atmospheric models and multiple flavors (optionally including sterile neutrinos and CP violation).
Solution method:
Direct solution of the Schrödinger equation for n flavors including matter effects, with sampling of the atmosphere.
Restrictions:
Energy loss and absorption of neutrinos inside the Earth is not modeled; they have to be handled independently.
Unusual features:
Completely configurable oscillation parameters (including optional sterile flavors), configurable and realistic Earth model including atmosphere.
Running time:
Roughly 100 neutrinos per second and CPU core (depends on energy and oscillation parameters).
In this paper, we present an electric-thermal drill with a novel design of a melting head that was developed within the EnEx-RANGE project. The design combines a short melting head with a large ...surface area of parabolic shape. It was succesfully tested in the laboratory as well as on Alpine glaciers (Langenferner and Mittelbergferner) and at the Ross Ice Shelf in Antarctica. In all these different environments, a high melting speed per specific power of typically 8.8 cm3 w−1 h−1 is achieved that is close to the ideal maximum bound of ~10.5–11.8 cm3 w−1 h−1 when neglecting all heat losses. It has also been demonstrated that the melting probe can be operated with typical equipment of small-scale field camps including a small power generator.
The Autonomous Pinger Unit (APU) is an electro-thermal drill with acoustic instrumentation developed for the project EnEx-RANGE in view of a future space mission for the sub-surface exploration of ...Saturn's moon Enceladus. A main goal is the development of navigation technology for an acoustic guidance system allowing maneuvering a probe through glacial ice. In total 13 APUs were built and tested in terrestrial analog scenarios on alpine glaciers. The APUs form a spatially distributed network that defines a system of reference for the navigation of the maneuverable probe to a point of interest. The APUs have a novel melting head, slow control systems, and a modern system-on-chip (SoC) module that controls the probe and processes the recorded data. The APUs use acoustic emitters and receivers to measure the transit time of acoustic signals between them, allowing for the position reconstruction of all APUs by trilateration. Several auxiliary sensors monitor the internal state of the probe and assist the position estimation. With this instrumentation, the APUs have the ability of dynamically optimizing themselves within the network by changing their position. This paper gives an overview of the developed APU hardware and presents performance results from the field tests.
The Serappis (SEarch for RAre PP-neutrinos In Scintillator) project aims at a precision measurement of the flux of solar
pp
neutrinos on the few-percent level. Such a measurement will be a relevant ...contribution to the study of solar neutrino oscillation parameters and a sensitive test of the equilibrium between solar energy output in neutrinos and electromagnetic radiation (solar luminosity constraint). The concept of Serappis relies on a small organic liquid scintillator detector (
∼
20 m
3
) with excellent energy resolution (
∼
2.5% at 1 MeV), low internal background and sufficient shielding from surrounding radioactivity. This can be achieved by a minor upgrade of the OSIRIS facility at the site of the JUNO neutrino experiment in southern China. To go substantially beyond current accuracy levels for the
pp
flux, an organic scintillator with ultra-low
14
C
levels (below
10
-
18
) is required. The existing OSIRIS detector and JUNO infrastructure will be instrumental in identifying suitable scintillator materials, offering a unique chance for a low-budget high-precision measurement of a fundamental property of our Sun that will be otherwise hard to access.
The development of ice-melting probes is driven by the scientific need to explore the subglacial aquatic environments, such as the subglacial lakes in Antarctica and subglacial water on some ...extraterrestrial planets. However, during the downward melting, a deviation of the melting trajectory might occur. If left unaddressed, the accumulated deviation will eventually lead to missing the probe's target. Therefore, it is necessary to build a theoretical model to describe the deviation for predicting the future melting trajectory and building the deviation correction system. The deviation comes from any asymmetric heating condition on the melting head. Generally, the Close-Contact Melting (CCM) theory is used to model the probe's melting process without any deviation, and there is only one attempt so far that applies the CCM theory to asymmetric heating conditions. Based on this initial attempt, we successfully expanded the CCM theory with asymmetric temperature profiles to conical thermal heads. Additionally, we simplified the model solving which leads to fewer influence factors compared to existing studies. The model indicates that the melting trajectory of a conical head is linear under asymmetric heating conditions, and the inclination angle of the trajectory is related to the ratio between the head's temperatures on each side and the head's cone angle. To validate the theoretical results, laboratory experiments have also been conducted with an innovative optical positioning method.
Speed of sound in bubble-free ice Vogt, Christian; Laihem, Karim; Wiebusch, Christopher
The Journal of the Acoustical Society of America,
12/2008, Volume:
124, Issue:
6
Journal Article
Peer reviewed
The speed of sound in a large volume of bubble-free ice was measured with high accuracy using a linear array of six piezoceramic lead zirconium titanate (PZT) receivers. This array was deployed in an ...approximately 3 m(3) water tank, which was cooled down to -20 degrees C. The freezing process was performed inside a cooling container. Bubble-free ice was obtained using a freeze control unit, which filters and degases the water during the freezing process. A dedicated geometry was used to position PZT receivers and an emitter such that systematic errors were minimized. With this setup the longitudinal and the transverse components of the speed of sound were measured at temperatures between 17 and 0 degrees C in water and between 0 and -20 degrees C in ice with an uncertainty of approximately 0.3%.
Within the Enceladus Explorer Initiative of the DLR Space Administration navigation technologies for a future space mission are in development. Those technologies are the basis for the search for ...extraterrestrial life on the Saturn moon Enceladus. An autonomous melting probe, the EnEx probe, aims to extract a liquid sample from a water reservoir below the icy crust. A first EnEx probe was developed and demonstrated in a terrestrial scenario at the Bloodfalls, Taylor Glacier, Antarctica in November 2014. To enable navigation in glacier ice two acoustic systems were integrated into the probe in addition to conventional navigation technologies. The first acoustic system determines the position of the probe during the run based on propagation times of acoustic signals from emitters at reference positions at the glacier surface to receivers in the probe. The second system provides information about the forefield of the probe. It is based on sonographic principles with phased array technology integrated in the probe’s melting head. Information about obstacles or sampling regions in the probe’s forefield can be acquired. The development of both systems is now continued in the project EnEx-RANGE. The emitters of the localization system are replaced by a network of intelligent acoustic enabled melting probes. These localize each other by means of acoustic signals and create the reference system for the EnEx probe. This presentation includes the discussion of the intelligent acoustic network, the acoustic navigation systems of the EnEx probe and results of terrestrial tests.
For the planned high-energy extension of the IceCube Neutrino Observatory in the glacial ice at the South Pole the spacing of detector modules will be increased with respect to IceCube. Because of ...these larger distances the quality of the geometry calibration based on pulsed light sources is expected to deteriorate. To counter this an independent acoustic geometry calibration system based on trilateration is introduced. Such an acoustic positioning system (APS) has already been developed for the Enceladus Explorer Project (EnEx), initiated by the DLR Space Administration. In order to integrate such APS-sensors into the IceCube detector the power consumption needs to be minimized. In addition, the frequency response of the front end electronics is optimized for positioning as well as the acoustic detection of neutrinos. The new design of the acoustic sensor and results of test measurements with an IceCube detector module will be presented.
PDF
