NPAC (Nuclear/Particle/Astro/Cosmo) Forum

Neutrinos are unique messengers from the high-energy universe. They can escape dense astrophysical environments, undeterred by intervening matter and radiation fields. The detection of high-energy astrophysical neutrinos in the TeV-PeV range by IceCube allows us to probe extreme cosmic sources and understand their emission processes in ways what would not be possible with photons alone. Enabling neutrino astrophysics in the coming decade will rest not only on the construction of new, more sensitive facilities, but also on the combined operation of multiple observatories capable of identifying additional tracers of hadronic emission. I will present a short overview of recent highlights from the neutrino sky and introduce a vision for how the coordinated operation of current and future multi-messenger observatories will help us deliver answers to some of the most pressing questions in high-energy astrophysics.
Host: 
Albrecht Karle
Speaker: Marcos Santander

 

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Room and Building: 
Room 4274, Chamberlin
The highest-energy particles discovered in Nature are ultra-high-energy cos-mic rays (UHECR). They carry energies orders of magnitude higher than that reached by man-made accelerators. Technological advances in the past thirty years have enabled us to precisely characterize the flux, composition, and ar-rival directions of UHECR. The Pierre Auger Observatory, the largest cosmic-ray experiment on Earth, is an observatory dedicated to the study of UHECR by detecting air showers produced in Earth’s atmosphere. Additionally, the cubic-kilometer IceCube Neutrino Observatory has discovered a diffuse flux of high-energy astrophysical neutrinos at PeV energies. However, the origins of UHECR remain an enduring mystery, and their connections with IceCube neu-trinos remain unclear. In this talk, I will review the state-of-the-art for our understanding of the UHE Universe and propose a road map that combines measurements from Pierre Auger, IceCube and other multi-messenger partners, utilizing data of UHE photons and astrophysical neutrinos, for the detection of the first possible UHE source.
Host: 
Albrecht Karle
Speaker: Lu Lu

 

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Room and Building: 
Room 4274, Chamberlin
Radio observations of the redshifted 21 cm line of hydrogen will allow exploration of cosmic epochs before the first luminous objects formed: the epoch of reionization, cosmic dawn, and the cosmic dark ages. This talk will describe the Lunar Orbit Array, a Chinese instrument under study to orbit the Moon to measure the global spectrum of the sky and make sky maps from 1 MHz to 200 MHz, corresponding to redshifts from ~ 1000 to 7.
Host: 
Peter Timbie
Speaker: Xuelei Chen National Astronomical Observatories of China/ Chinese Academy of Sciences (NAOC)

 

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Room and Building: 
Sterling B343 (NOTE NEW LOCATION)
Topics in top-higgs physics and computing for high energy physics
Speaker: Ken Bloom University of Nebraska - Lincoln

 

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Room and Building: 
4274 Chamberlin Hall
MicroBooNE is a liquid argon time projection chamber in the Booster Neutrino Beam at Fermilab. The technology provides high-resolution imaging of neutrino interactions leading to low-threshold event reconstruction with full angular coverage. As such, this is an ideal place to probe neutrino-argon interactions in the hundreds-of MeV to few-GeV energy range. This talk presents a start-to-end overview demonstrating the physics capabilities of the detector. I will talk about cosmic ray measurement and characterisation, our dominant background. Furthermore, I will describe the flavour-agnostic neutrino pre-selection, based on the combination of the charge collected by the TPC and the optical information form the PMT system. An overview of recent measurements of neutrino interactions in MicroBooNE, including inclusive charged-current interactions, will be given. I will conclude summarising the ongoing efforts towards our first low-energy-excess results
Host: 
Francis Halzen
Speaker: Wouter Van De Pontseele

 

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Room and Building: 
Chamberlin 4274
Neutrino oscillation experiments such as NOvA and T2K search for the disappearance and appearance of muon and electron flavor neutrinos in a predominately muon-type beam. These experiments are currently measuring the oscillation parameters to greater precision but will not be able to measure the CP phase with enough significance to pin down CP violation in the lepton sector. The next generation of experiments, DUNE and Hyper-Kamiokande, will push the field into its precision era, requiring precise predictions of the flux and neutrino interactions used to measure CP violation.

The MINERvA experiment is a dedicated neutrino interaction experiment set in the NuMI beamline at Fermi National Accelerator Laboratory. The purpose of the experiment is to measure neutrino interactions off a variety of nuclear targets to probe nuclear effects and inform modeling of neutrino interactions. The experiment measures interactions over a wide range of Q2 and W including interactions in the quasi-elastic, resonant, and shallow to deep inelastic scattering regions. The experiment has run with two beam energies peaked at ~3 and 6 GeV in both neutrino and anti-neutrino enhanced modes.

In this seminar, I will describe the current state of neutrino oscillation physics and how MINERvA data will be used in future experiments. I will specifically describe the extensive tuning exercise MINERvA has done to describe interactions in the quasi-elastic into the resonant pion regions of kinematic phase space. I will also discuss the lessons learned and a description of the next generation measurements to prepare for the DUNE experiment.
Host: 
Tianlu Yuan
Speaker: Dan Ruterbories University of Rochester / MINERvA

 

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Room and Building: 
4274 Chamberlin Hall
Neutrino flavor oscillations provided the first break in the Standard Model by proving that neutrinos have nonzero mass, but cannot constrain the absolute mass scale. The most sensitive method to directly measure the mass scale is observation of the tritium beta-decay spectrum endpoint and extraction of the electron antineutrino mass. Project 8 is a next-generation experiment based on the novel Cyclotron Radiation Emission Spectroscopy (CRES) technique to perform a radio-frequency-based measurement of the tritium beta spectrum. The goal of the phased program is to reach a mass sensitivity below 40 meV, completely covering the allowed region of the inverted mass hierarchy. I will present studies performed on the mono-energetic conversion electrons of 83mKr and the ongoing tritium data-taking campaign, which is the first use of the CRES technique for a continuous spectrum measurement. In parallel, an R&D program is being executed to to demonstrate critical technologies for scaling CRES to m^3-scale volumes and for delivering a high-intensity atomic tritium source, establishing a pathway for future experiments based on this technology.
Speaker: Walter Pettus University of Washington

 

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Room and Building: 
5310 Chamberlin (if available)
Host: 
Balantekin
Speaker: Kanji Mori University of Tokyo

 

Available Downloads:

Room and Building: 
5290 Chamberlin Hall
Last year, LIGO-VIRGO collaborations reported detection of the first neutron star merger event, GW170817, which accompanied with observations of electromagnetic counterparts from radio to gamma rays. High-energy gamma rays and neutrinos were not observed. However, the mergers of neutron stars are expected to produce these high-energy particles. Relativistic jets are expected to be launched when the neutron stars merge, which can be a source of high-energy neutrinos. Also, the central remnant object after the merger event, either a black hole or a neutron star, can produce high-energy photons weeks to months after the merger. In addition, the neutron star mergers produce massive and fast ejecta, which can be a source of Galactic high-energy cosmic rays, analogous to supernova remnants. In this talk, I will discuss these high-energy processes and prospects for multi-messenger detections related to the neutron star mergers .
Host: 
Francis Halzen
Speaker: Shigeo Kimura PennState

 

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Room and Building: 
4274 Chamberlin Hall
The tau neutrino is the Standard Model particle with the fewest identified events. Most tau-neutrino interactions cannot be distinguished from other flavor neutrino interactions. This is due to the large mass of the tau, which causes the production threshold to open up at a few GeV, and the prompt tau decay. The study of astrophysical neutrinos provides important clues about cosmic particle accelerators. In particular, the tau neutrino fraction at Earth is directly translatable to the source flavor composition and can constrain source production mechanisms. For neutrinos of energies greater than ~100 TeV, IceCube becomes sensitive to the identification of tau-neutrino charged current interaction on an event-by-event basis via the double bang channel. This channel consists two energy depositions one from the tau production and the other from the tau decay. With no significant tau neutrino production expected at the source, IceCube is the first experiment able to observe neutrino oscillations over cosmological baselines. I will present and discuss recent measurements of the astrophysical flavor composition.
Host: 
Carlos Argüelles
Speaker: Juliana Stachurska DESY

 

Available Downloads:

Room and Building: 
5280 Chamberlin Hall

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