skip to main content

Search for: All records

Creators/Authors contains: "Hughes, K"

Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher. Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?

Some links on this page may take you to non-federal websites. Their policies may differ from this site.

  1. When Earth-skimming tau neutrinos interact within the Earth, they generate upgoing tau leptons that can decay in the atmosphere, forming extensive air showers. The Beamforming Elevated Array for COsmic Neutrinos (BEACON) is a novel detector concept that utilizes a radio interferometer atop a mountain to search for the radio emission due to these extensive air showers. The prototype, located at the White Mountain Research Station in California, consists of 4 crossed-dipole antennas operating in the 30-80 MHz range and uses a directional interferometric trigger for reduced thresholds and background rejection. The prototype will first be used to detect down-going cosmicmore »rays to validate the detector model. A Monte-Carlo simulation was developed to predict the acceptance of the prototype to cosmic rays, as well as the expected rate of detection. In this simulation, cosmic ray induced air showers with random properties are generated in an area around the prototype array. It is then determined if a given shower triggers the array using radio emission simulations from ZHAireS and antenna modelling from XFdtd. Here, we present the methodology and results of this simulation.« less
    Free, publicly-accessible full text available March 18, 2023
  2. Free, publicly-accessible full text available March 28, 2023
  3. Abstract Over the last 25 years, radiowave detection of neutrino-generated signals, using cold polar ice as the neutrino target, has emerged as perhaps the most promising technique for detection of extragalactic ultra-high energy neutrinos (corresponding to neutrino energies in excess of 0.01 Joules, or 10 17 electron volts). During the summer of 2021 and in tandem with the initial deployment of the Radio Neutrino Observatory in Greenland (RNO-G), we conducted radioglaciological measurements at Summit Station, Greenland to refine our understanding of the ice target. We report the result of one such measurement, the radio-frequency electric field attenuation length $L_\alpha$ .more »We find an approximately linear dependence of $L_\alpha$ on frequency with the best fit of the average field attenuation for the upper 1500 m of ice: $\langle L_\alpha \rangle = ( ( 1154 \pm 121) - ( 0.81 \pm 0.14) \, ( \nu /{\rm MHz}) ) \,{\rm m}$ for frequencies ν ∈ [145 − 350] MHz.« less
    Free, publicly-accessible full text available May 30, 2023
  4. Two PIEZO mechanosensitive cation channels, PIEZO1 and PIEZO2, have been identified in mammals, where they are involved in numerous sensory processes. While structurally similar, PIEZO channels are expressed in distinct tissues and exhibit unique properties. How different PIEZOs transduce force, how their transduction mechanism varies, and how their unique properties match the functional needs of the distinct tissues where they are expressed remain all-important unanswered questions. The nematode Caenorhabditis elegans has a single PIEZO ortholog (pezo-1) predicted to have twelve isoforms. These isoforms share many transmembrane domains, but differ in those that distinguish PIEZO1 and PIEZO2 in mammals. Here wemore »use translational and transcriptional reporters to show that long pezo-1 isoforms are selectively expressed in mesodermally derived tissues (such as muscle and glands). In contrast, shorter pezo-1 isoforms are primarily expressed in neurons. In the digestive system, different pezo-1 isoforms appear to be expressed in different cells of the same organ. We show that pharyngeal muscles, glands, and valve rely on long pezo-1 isoforms to respond appropriately to the presence of food. The unique pattern of complementary expression of pezo-1 isoforms suggest that different isoforms possess distinct functions. The number of pezo-1 isoforms in C. elegans, their differential pattern of expression, and their roles in experimentally tractable processes make this an attractive system to investigate the molecular basis for functional differences between members of the PIEZO family of mechanoreceptors.« less
  5. Free, publicly-accessible full text available June 1, 2023
  6. Abstract Since summer 2021, the Radio Neutrino Observatory in Greenland (RNO-G) is searching for astrophysical neutrinos at energies $${>10}$$ > 10  PeV by detecting the radio emission from particle showers in the ice around Summit Station, Greenland. We present an extensive simulation study that shows how RNO-G will be able to measure the energy of such particle cascades, which will in turn be used to estimate the energy of the incoming neutrino that caused them. The location of the neutrino interaction is determined using the differences in arrival times between channels and the electric field of the radio signal ismore »reconstructed using a novel approach based on Information Field Theory. Based on these properties, the shower energy can be estimated. We show that this method can achieve an uncertainty of 13% on the logarithm of the shower energy after modest quality cuts and estimate how this can constrain the energy of the neutrino. The method presented in this paper is applicable to all similar radio neutrino detectors, such as the proposed radio array of IceCube-Gen2.« less
    Free, publicly-accessible full text available February 1, 2023