Graduate Program Events |
Events During the Week of April 24th through May 1st, 2022
Monday, April 25th, 2022
- No events scheduled
Tuesday, April 26th, 2022
- Hunting for cosmic neutrino sources from Giga- to Exa-electronvolt with IceCube
- Time: 2:00 pm
- Place: B343 Sterling
- Speaker: Alex Pizzuto, Physics PhD Graduate Student
- Abstract: Ever since the first observation of cosmic rays over a century ago, the origins of these high-energy particles has remained a mystery. Identifying and understanding the sources of these cosmic rays could provide invaluable insight into not only astrophysics but also fundamental particle physics. The IceCube Neutrino Observatory, a cubic-kilometer neutrino telescope instrumented at the geographic South Pole, has made remarkable progress on this front -- first with the detection of a diffuse astrophysical neutrino flux in 2013, and later with the identification of a particular flaring blazar as a promising neutrino source. However, the sources of the vast majority of the diffuse neutrino flux remain unidentified. The goal of this thesis is to identify astrophysical neutrino sources despite our limited detection threshold. We show how analyzing neutrino data with new techniques can reveal an immense deal about the nature of the universe's most energetic particle accelerators. After providing a description of the state of the field and a quick overview of the general analysis techniques used, we present a variety of analyses focused on searching for neutrino emission from promising classes of astrophysical transients. Although all of these analyses resulted in non-detections, we are hopeful that the tools presented here will assist with the identification of cosmic neutrino sources in the years to come.
- Host: Justin Vandenbroucke
Wednesday, April 27th, 2022
- No events scheduled
Thursday, April 28th, 2022
- No events scheduled
Friday, April 29th, 2022
- Intensity Mapping: Science and Instrumentation Across the Electromagnetic Spectrum
- Time: 2:00 pm
- Place: B343 Sterling or join online:
- Speaker: Trevor Oxholm, Physics PhD Graduate Student
- Abstract: Line intensity mapping is a growing technique for obtaining tomographic maps of the universe. Line intensity maps feature the integrated emission of a target spectral line from all galaxies within the field of view, making it an unbiased tracer of galaxy emission and a strong tool for galaxy evolution studies. Furthermore, line intensity mapping surveys may probe unprecedented volumes of the universe with modest time requirements, allowing for leading sensitivities of cosmological parameters. In this thesis, I describe modeling efforts for measurements of the intensity mapping signal and for instrumentation developed for the Experiment for Cryogenic Large- aperture Intensity Mapping (EXCLAIM!). EXCLAIM is a pathfinding balloon-borne intensity mapping instrument aiming to map ionized carbon ([CII]) and carbon monoxide (CO) at redshifts 2.5 < z < 3.5 and z < 0.64, respectively. I characterize the target observables in the survey and describe methods for forecasting the performance of the instrument. I apply these forecasting tools to the EXCLAIM survey and to a hypothetical space-based survey, which may be free from the limitations of cosmic variance. The EXCLAIM detectors and optical systems are also described in detail, and with a dual focus on system-level requirements. EXCLAIM features nascent superconducting spectrometer and detector technologies, which must be carefully characterized and modeled before the flight. I describe an operational procedure that may be used to optimize the detectors for an evolving signal, providing a critical advantage for EXCLAIM’s detectors over competing technologies. Finally, the optical system is modeled and shown to comply with system-level mission goals.
- Host: Peter Timbie