We present the first observational limits to the ultra-high-energy (UHE) neutrino flux from the Galactic Centre, and from Centaurus A which is the nearest active galactic nucleus. These results are ...based on our 'Lunar UHE Neutrino Astrophysics using the Square Kilometre Array' (LUNASKA) project experiments at the Australia Telescope Compact Array (ATCA). We also derive limits for the previous experiments and compare these limits with expectations for acceleration and superheavy dark matter models of the origin of UHE cosmic rays.
NuRadioMC is a Monte Carlo framework designed to simulate ultra-high energy neutrino detectors that rely on the radio detection method. This method exploits the radio emission generated in the ...electromagnetic component of a particle shower following a neutrino interaction. NuRadioMC simulates everything from the neutrino interaction in a medium, the subsequent Askaryan radio emission, the propagation of the radio signal to the detector and finally the detector response. NuRadioMC is designed as a modern, modular Python-based framework, combining flexibility in detector design with user-friendliness. It includes a state-of-the-art event generator, an improved modelling of the radio emission, a revisited approach to signal propagation and increased flexibility and precision in the detector simulation. This paper focuses on the implemented physics processes and their implications for detector design. A variety of models and parameterizations for the radio emission of neutrino-induced showers are compared and reviewed. Comprehensive examples are used to discuss the capabilities of the code and different aspects of instrumental design decisions.
This paper examines the effect of the type of the emulsifying protein (EP) (sodium caseinate (SC) and whey protein isolate (WPI)) on both oil-in-water liquid-like emulsions (Es) and the corresponding ...cold gelled emulsions (GEs), and also the effect of addition of carob extract rich in condensed tannins (T). The systems, intended as functional food ingredients, were studied in various different respects, including rheological behaviour, in vitro gastrointestinal digestion with determination of the release of non-extractable proanthocyanidins (NEPA) from T, antioxidant activity and lipolysis. EP significantly affects the rheological behaviour of both Es and GEs. T incorporation produced a structural reinforcement of GEs, especially in the case of SC. The digests from Es displayed a higher antioxidant activity than those from GEs. T lipase inhibition was observed only in the formulations with WPI. Our results highlight the importance, in the design of functional foods, of analyzing different variables when incorporating a bioactive compound into a food or emulsion in order to select the better combination for the desired objective, owing to the complex interplay of the various components.
This paper presents our results for full 3-D simulations of very-high to ultra-high energy electromagnetic cascades – and the associated coherent Cherenkov radiation – as might be produced by ...high-energy neutrino interactions in dense media. Using “thinning” techniques, we develop an algorithm based on the existing “ZHS” code, and demonstrate that the new “ZHS-thinned” code can produce fast and accurate results for showers up to
10
20
eV
. Using ZHS-thinned, we develop new parameterisations for the radiation from showers in ice, salt, and the lunar regolith, with a separate treatment of the megaregolith (deep regolith). Our parameterisations include for the first time a method to simulate fluctuations in shower length induced by the LPM effect. Our results, which avoid the pit-falls of scaling simulations from lower energies, allow improved calculations of the detection probability for experiments searching for high-energy neutrinos using the radio technique.
Although the metastasic breast cancer is still an incurable disease, recent advances have increased significantly the time to progression and the overall survival. However, too much information has ...been produced in the last 2 years, so a well-based guideline is a valuable document in treatment decision making. The SEOM guidelines are intended to make evidence-based recommendations on how to manage patients with advanced and recurrent breast cancer to achieve the best patient outcomes based on a rational use of the currently available therapies. To assign a level of certainty and a grade of recommendation the United States Preventive Services Task Force guidelines methodology was selected as reference.
The sequential cooking–freezing–reheating (CFR) method was studied. Sardine (
Sardina pilchardus Walb) fillets were cooked by frying, oven-baking or grilling, frozen, and then reheated using ...conventional or microwave ovens in order to study changes occurring in the proximate and fatty acid compositions. Both cooking and freezing–reheating affected (
P<0.001) the proximate composition. Frying produced the highest water loss and fat gain, followed by grilling, and then by oven-baking. Microwave oven-reheating (MR) induced higher dehydration than conventional oven-reheating (OR), with grilled–frozen–MR samples also loosing fat and ash. Frying significantly (
P<0.001) affects the fatty acid composition of sardine, increasing oleic and linoleic acids and decreasing eicosapentaenoic and docosahexaenoic acids. Oven-baking and grilling minimally affected the fatty acid content. Freezing–reheating significantly affected (
P<0.001) the fatty acid composition with the content of oleic acid increasing and those of the ω-3 fatty acids, decreasing more in MR than in OR. Thus, according to the positive effect attributed to ω-3 fatty acids, cooked samples with no further treatment would be preferred to their respective CFR counterparts. However, OR should be used instead of MR when the CFR system is performed.
We present the design, implementation and data taking performance of the MIcrowave Detection of Air Showers (MIDAS) experiment, a large field of view imaging telescope designed to detect microwave ...radiation from extensive air showers induced by ultra-high energy cosmic rays. This novel technique may bring a tenfold increase in detector duty cycle when compared to the standard fluorescence technique based on detection of ultraviolet photons. The MIDAS telescope consists of a 4.5m diameter dish with a 53-pixel receiver camera, instrumented with feed horns operating in the commercial extended C-Band (3.4–4.2GHz). A self-trigger capability is implemented in the digital electronics. The main objectives of this first prototype of the MIDAS telescope – to validate the telescope design, and to demonstrate a large detector duty cycle – were successfully accomplished in a dedicated data taking run at the University of Chicago campus prior to installation at the Pierre Auger Observatory.
•The MIDAS objective is to detect ultra high energy cosmic rays using microwaves.•GHz radiation could provide a powerful alternative to current detection methods.•The MIDAS prototype explores the potential of the microwave technique.
Recent results from the Pierre Auger Observatory Alvarez-Muñiz, J.
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2009, Letnik:
604, Številka:
1
Journal Article
Recenzirano
The Southern Pierre Auger Observatory is close to completion. Data have been taken since January 2004 while the array was being constructed, what amounts to
>
1
year of exposure with the full array. ...Results on the energy spectrum of UHECRs above
10
18
eV
, on the mass composition of the primary flux, and on the arrival directions of the most energetic events are presented. A limit on the diffuse flux of neutrinos above
∼
10
17
eV
has also been placed.
► Influence of thinning procedure on shower fluctuations in simulations. ► Expression to estimate physical and artificial (thinning) shower fluctuations. ► Study of physical shower fluctuations at ...ground.
By means of Monte Carlo simulations of extensive air showers (EAS), we have performed a comprehensive study of the shower to shower fluctuations affecting the longitudinal and lateral development of EAS. We split the fluctuations into physical fluctuations and those induced by the thinning procedure customarily applied to simulate showers at EeV energies and above. We study the influence of thinning on the calculation of the shower to shower fluctuations in the simulations. For thinning levels larger than
R
thin
=
10
−5
−
10
−6, the determination of the shower to shower fluctuations is hampered by the artificial fluctuations induced by the thinning procedure. However, we show that shower to shower fluctuations can still be approximately estimated, and we provide expressions to calculate them. The influence of fluctuations of the depth of first interaction on the determination of shower to shower fluctuations is also addressed.
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