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Abstract We conducted an all‐sky imaging transient search with the Owens Valley Radio Observatory Long Wavelength Array (OVRO‐LWA) data collected during the Perseid meteor shower in 2018. The data collection during the meteor shower was motivated to conduct a search for intrinsic radio emission from meteors below 60 MHz known as the meteor radio afterglows (MRAs). The data collected were calibrated and imaged using the core array to obtain lower angular resolution images of the sky. These images were input to a pre‐existing LWA transient search pipeline to search for MRAs as well as cosmic radio transients. This search detected 5 MRAs and did not find any cosmic transients. We further conducted peeling of bright sources, near‐field correction, visibility differencing and higher angular resolution imaging using the full array for these 5 MRAs. These higher angular resolution images were used to study their plasma emission structures and monitor their evolution as a function of frequency and time. With higher angular resolution imaging, we resolved the radio emission size scales to less than 1 km physical size at 100 km heights. The spectral index mapping of one of the long duration event showed signs of diffusion of plasma within the meteor trails. The unpolarized emission from the resolved radio components suggest resonant transition radiation as the possible radiation mechanism of MRAs.
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Time-Domain Science Pipelines for the OVRO-LWA
The Owens Valley Radio Observatory Long Wavelength Array is a low radio frequency all-sky imaging radio interferometer. The full 352-element array will generate more than 2 TB of visibility data per hour of observation. One of the array’s primary science cases, the search for variable radio emission from exoplanets and for transients, require fast and high dynamic range interferometric imaging. Here we detail the design and implementation of a two-pipeline infrastructure that minimizes development cost: an offline pipeline that facilitates experimentation with existing pack-ages, and a real-time pipeline that minimizes overhead.
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- Award ID(s):
- 1828784
- PAR ID:
- 10410958
- Date Published:
- Journal Name:
- 2022 3rd URSI Atlantic and Asia Pacific Radio Science Meeting (AT-AP-RASC)
- Page Range / eLocation ID:
- 1 to 5
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Conference Paper:
- https://doi.org/10.23919/at-ap-rasc54737.2022.9814199
