699 research outputs found
Searching for tau neutrinos with Cherenkov telescopes
Cherenkov telescopes have the capability of detecting high energy tau
neutrinos in the energy range of 1--1000 PeV by searching for very inclined
showers. If a tau lepton, produced by a tau neutrino, escapes from the Earth or
a mountain, it will decay and initiate a shower in the air which can be
detected by an air shower fluorescence or Cherenkov telescope. In this paper,
we present detailed Monte Carlo simulations of corresponding event rates for
the VERITAS and two proposed Cherenkov Telescope Array sites: Meteor Crater and
Yavapai Ranch, which use representative AGN neutrino flux models and take into
account topographic conditions of the detector sites. The calculated neutrino
sensitivities depend on the observation time and the shape of the energy
spectrum, but in some cases are comparable or even better than corresponding
neutrino sensitivities of the IceCube detector. For VERITAS and the considered
Cherenkov Telescope Array sites the expected neutrino sensitivities are up to
factor 3 higher than for the MAGIC site because of the presence of surrounding
mountains.Comment: arXiv admin note: text overlap with arXiv:1308.019
Primary Particle Type of the Most Energetic Fly's Eye Air Shower
The longitudinal profile of the most energetic cosmic-ray air shower measured
so far, the event recorded by the Fly's Eye detector with a reconstructed
primary energy of about 320 EeV, is compared to simulated shower profiles. The
calculations are performed with the CORSIKA code and include primary photons
and different hadron primaries. For primary photons, preshower formation in the
geomagnetic field is additionally treated in detail. For primary hadrons, the
hadronic interaction models QGSJET01 and SIBYLL2.1 have been employed. The
predicted longitudinal profiles are compared to the observation. A method for
testing the hypothesis of a specific primary particle type against the measured
profile is described which naturally takes shower fluctuations into account.
The Fly's Eye event is compatible with any assumption of a hadron primary
between proton and iron nuclei in both interaction models, although differences
between QGSJET01 and SIBYLL2.1 in the predicted profiles of lighter nuclei
exist. The primary photon profiles differ from the data on a level of ~1.5
sigma. Although not favoured by the observation, the primary photon hypothesis
can not be rejected for this particular event.Comment: 20 pages, 8 figures; v2 matches version accepted by Astroparticle
Physic
Search for tau neutrinos at PeV energies and beyond with the MAGIC telescopes
The MAGIC telescopes, located at the Roque de los Muchachos Observatory (2200
a.s.l.) in the Canary Island of La Palma, are placed on the top of a mountain,
from where a window of visibility of about 5 deg in zenith and 80 deg in
azimuth is open in the direction of the surrounding ocean. This permits to
search for a signature of particle showers induced by earth-skimming cosmic tau
neutrinos in the PeV to EeV energy range arising from the ocean. We have
studied the response of MAGIC to such events, employing Monte Carlo simulations
of upward-going tau neutrino showers. The analysis of the shower images shows
that air showers induced by tau neutrinos can be discriminated from the
hadronic background coming from a similar direction. We have calculated the
point source acceptance and the expected event rates, for a sample of generic
neutrino fluxes from photo-hadronic interactions in AGNs. The analysis of about
30 hours of data taken toward the sea leads to a point source sensitivity for
tau neutrinos at the level of the down-going point source analysis of the
Pierre Auger Observatory, if the AUGER observation time is dedicated to a
similar amount by MAGIC.Comment: Proceedings of EPS-HEP 2017, European Physical Society conference on
High Energy Physics, 5-12 July 2017, Venice, Italy. arXiv admin note:
substantial text overlap with arXiv:1708.0614
Symposium Introduction
On April 12, 2019, scholars gathered at Brooklyn Law School to consider the past, the present, and the future of free speech, and concerns about incitement that militate toward suppression. The speakers provided incisive and timely insight on these important matters—insight that is reflected in the papers published in this symposium issue of the Brooklyn Law Review. This introduction provides an overview of this symposium issue and the questions presented by each article
Sensitivity for tau neutrinos at PeV energies and beyond with the MAGIC telescopes
The MAGIC telescopes, located at the Roque de los Muchachos Observatory (2200
a.s.l.) in the Canary Island of La Palma, are placed on the top of a mountain,
from where a window of visibility of about 5 deg in zenith and 80 deg in
azimuth is open in the direction of the surrounding ocean. This permits to
search for a signature of particle showers induced by earth-skimming cosmic tau
neutrinos in the PeV to EeV energy range arising from the ocean. We have
studied the response of MAGIC to such events, employing Monte Carlo simulations
of upward-going tau neutrino showers. The analysis of the shower images shows
that air showers induced by tau neutrinos can be discriminated from the
hadronic background coming from a similar direction. We have calculated the
point source acceptance and the expected event rates, assuming an incoming tau
neutrino flux consistent with IceCube measurements, and for a sample of generic
neutrino fluxes from photo-hadronic interactions in AGNs. The analysis of about
30 hours of data taken toward the sea leads to a point source sensitivity for
tau neutrinos at the level of the down-going point source analysis of the
Pierre Auger Observatory.Comment: Proceedings of the 35th International Cosmic Ray Conference (ICRC
2017), Bexco, Busan, Korea,(arXiv:1708.05153
Identifying Promising Candidate Radiotherapy Protocols via GPU-GA in-silico
Around half of all cancer patients, world-wide, will receive some form of
radiotherapy (RT) as part of their treatment. And yet, despite the rapid
advance of high-throughput screening to identify successful chemotherapy drug
candidates, there is no current analogue for RT protocol screening or discovery
at any scale. Here we introduce and demonstrate the application of a
high-throughput/high-fidelity coupled tumour-irradiation simulation approach,
we call "GPU-GA", and apply it to human breast cancer analogue - EMT6/Ro
spheroids. By analysing over 9.5 million candidate protocols, GPU-GA yields
significant gains in tumour suppression versus prior state-of-the-art
high-fidelity/-low-throughput computational search under two clinically
relevant benchmarks. By extending the search space to hypofractionated areas (>
2 Gy/day) yet within total dose limits, further tumour suppression of up to
33.7% compared to state-of-the-art is obtained. GPU-GA could be applied to any
cell line with sufficient empirical data, and to many clinically relevant RT
considerations
An indigenous system for collection of Black soldierfly pupae and its nutritional evaluation for making fish feeds
Black soldierfly (BSF) pupae can be utilized as an excellent means for the bioconversion of organic wastes into high value sustainable protein and lipid ingredient for aquaculture. The life cycle of this insect begins with eggs laid in clutches of approximately 500 numbers. The eggs are about 1 mm in size and hatch into larvae within 4 days to two weeks. The larva feeds on organic waste and metamorphose into a pre-pupa, normally within 2 weeks which is the most nutrient rich stage in the BSF life cycle. At this stage it can be harvested periodically and converted into a feed ingredient for aquaculture. An indigenous small-scale system for the production of BSF by utilizing waste food from the departmental canteen of ICAR-CMFRI was attempte
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