Seminars 2022/2023

Kieran Cleary, 21st September, 2022

 

 

Seminar Speaker: Kieran Cleary
Venue:

 

 G07, Kane Building, UCC

Time and Date: 

Wednesday,  21st September, 2022

11am

Title:

 

Early Science Results from the CO Mapping Array Project  

Abstract:

The CO Mapping Array Project (COMAP) aims to use line intensity mapping (LIM) of carbon monoxide (CO) to trace the global properties of galaxies over cosmic time, back to the Epoch of Reionization. To validate the technologies, observing strategies, and analysis techniques needed for this goal, a Pathfinder instrument has been constructed and fielded at the Owens Valley Radio Observatory.

Sensitive to CO(1-0) emission from z=2.4-3.4 and a fainter contribution from CO(2-1) at z=6-8, the Pathfinder is surveying 12 sq. deg. in a 5-year observing campaign to detect the CO signal from z~3. Based on our first year of observations alone, we have obtained for the first time, a direct constraint on the clustering amplitude of the CO power spectrum at z~3, allowing us to rule out two models from the literature. At the conclusion of the 5-year Pathfinder survey, we forecast a detection of the clustering amplitude, molecular gas density and CO-galaxy cross-spectrum at high significance. The next phase of the experiment will add a new receiver that extends the reach of COMAP to the Epoch of Reionization.

 

 

 

Jerry Moloney, 12th September, 2022

 

 

Seminar Speaker: Jerry Moloney
Venue:

 

 B10A, Kane Building, UCC

Time and Date: 

Monday,  12th September, 2022, 4pm

Title:

 

Laser Pulse driven Fog Clearing, Nonlinear localization through turbulence and Extreme NLO in Dielectric/Plasmonic Metasurfaces  

Abstract:

Long wave intense ultrashort laser pulses are shown to be capable of breaking up large water droplets in fog, thereby opening up transient windows to enable GHz communications. Larger water droplets in fog tend to trap light energy via Mie resonances and lead to significant loss via isotropic scattering. I will discuss a multiphysics approach to modeling the full physical process of ultrafast fs scale energy deposition, slower thermal and carrier relaxation, shock wave generation and finally water droplet disruption. The model includes 3D vector Maxwell , Navier Stokes hydrodynamic and the application of thermomechanical steady state criteria to describe final breakup of large micron sized droplets to hundreds of nm scale fragments. We will also discuss the implementation of the same theoretical framework to describe highly localized nonlinear enhancement in plasmonic and dielectric metasurfaces. Finally, we will move beyond a Maxwell approach to study tens to hundreds of meter long localization of high energy long wave pulses in strong turbulence.

 

 

 

Department of Physics

Roinn na Fisice

Room 213 (Physics Office), 2nd floor, Kane Science Building, University College Cork, Ireland.,

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