Fwd: VERSIM/GEM Journal Club Invitation

[Jonathan]

---------- Forwarded message ---------
From: František Němec <frantis...@matfyz.cuni.cz>
Date: Tue, Sep 29, 2026 at 1:31 PM
Subject: VERSIM/GEM Journal Club Invitation
To:

Dear colleagues,

Please find below an invitation for the next VERSIM/GEM Journal Club meeting (7 October).

Frantisek

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Hello everyone, 

We are excited to announce our upcoming VERSIM/GEM Journal Club talk by Paraksh Vankawala from UC Boulder, on October 7th! They will be presenting their work on detecting hiss waves using a computer vision model and constraining the roles of its source mechanisms. 

The abstract and the Zoom link are provided below. More details about the journal club can be found here: https://aurora.troja.mff.cuni.cz/versim/index_jc.html  

We hope to see many of you there!

Best wishes, 

Rachel, Mirek, Jodie, Yang and Suhail

Date and time: Oct 7, 2026 @ 9am PDT / 12pm EDT / 4pm UTC / 5pm BST / 6pm CEST 

Zoom link: https://uiowa.zoom.us/j/97662932115 

Speaker: Paraksh Vankawala (UC Boulder)

Title: Exploring the Origins of Plasmaspheric Hiss Through a Computer Vision Guided Wave Analysis

Abstract: Plasma waves, including chorus, plasmaspheric hiss, and lightning-generated whistlers (LGWs), play a central role in radiation belt dynamics, yet the relative contributions of source mechanisms for plasmaspheric hiss remain unresolved. To investigate proposed contributions from local generation, chorus, and LGWs, we constructed a mission-scale catalog of these wave populations from seven years of Van Allen Probes magnetic field burst-mode observations using a computer vision detection model. Spectral power density, wave normal angle (WNA), and polarization information were combined into three-channel Physics Augmented Vision Analysis (PAVA) images and classified using a YOLOv11 object detection model. Using this catalog, we examine wave occurrence, WNA, spectral power density, and normalized frequency as functions of magnetic local time, geomagnetic activity, and plasmapause-relative position (ΔL). The results reveal systematic variations in hiss properties across the plasmasphere and plume regions and distinct relationships between hiss and neighboring chorus populations, providing new constraints on the relative roles of wave propagation and local generation in producing plasmaspheric hiss. These findings demonstrate the value of computer vision models for mission-scale investigations of plasma wave generation and radiation belt dynamics.