Matches in SemOpenAlex for { <https://semopenalex.org/work/W4385262020> ?p ?o ?g. }
Showing items 1 to 67 of
67
with 100 items per page.
- W4385262020 abstract "One key challenge in detecting 21 cm cosmological signal at z > 6 is to separate the cosmological signal from foreground emission. This can be studied in a power spectrum space where the foreground is confined to low delay modes whereas the cosmological signal can spread out to high delay modes. When there is a calibration error, however, chromaticity of gain errors propagates to the power spectrum estimate and contaminates the modes for cosmological detection. The Hydrogen Epoch of Reionization Array (HERA) employs a high-precision calibration scheme using redundancy in measurements. In this study, we focus on the gain errors induced by nonredundancies arising from feed offset relative to the HERA's 14 meter parabolic dish element, and investigate how to mitigate the chromatic gain errors using three different methods: restricting baseline lengths for calibration, smoothing the antenna gains, and applying a temporal filter prior to calibration. With 2 cm/2 degree perturbations for translation/tilting motions, a level achievable under normal HERA operating conditions, the combination of the baseline cut and temporal filtering indicates that the spurious gain feature due to nonredundancies is significantly reduced, and the power spectrum recovers the clean foreground-free region. We found that the mitigation technique works even for large feed motions but in order to keep a stable calibration process, the feed positions need to be constrained to 2 cm for translation motions and 2 degree for tilting offset relative to the dish's vertex." @default.
- W4385262020 created "2023-07-26" @default.
- W4385262020 creator A5001024440 @default.
- W4385262020 creator A5003070726 @default.
- W4385262020 creator A5004614868 @default.
- W4385262020 creator A5024608470 @default.
- W4385262020 creator A5027325194 @default.
- W4385262020 creator A5036630991 @default.
- W4385262020 creator A5046214946 @default.
- W4385262020 creator A5053723136 @default.
- W4385262020 creator A5076638185 @default.
- W4385262020 creator A5081982629 @default.
- W4385262020 date "2023-07-24" @default.
- W4385262020 modified "2023-09-26" @default.
- W4385262020 title "The Impact of Beam Variations on Power Spectrum Estimation for 21 cm Cosmology II: Mitigation of Foreground Systematics for HERA" @default.
- W4385262020 doi "https://doi.org/10.48550/arxiv.2307.12826" @default.
- W4385262020 hasPublicationYear "2023" @default.
- W4385262020 type Work @default.
- W4385262020 citedByCount "0" @default.
- W4385262020 crossrefType "posted-content" @default.
- W4385262020 hasAuthorship W4385262020A5001024440 @default.
- W4385262020 hasAuthorship W4385262020A5003070726 @default.
- W4385262020 hasAuthorship W4385262020A5004614868 @default.
- W4385262020 hasAuthorship W4385262020A5024608470 @default.
- W4385262020 hasAuthorship W4385262020A5027325194 @default.
- W4385262020 hasAuthorship W4385262020A5036630991 @default.
- W4385262020 hasAuthorship W4385262020A5046214946 @default.
- W4385262020 hasAuthorship W4385262020A5053723136 @default.
- W4385262020 hasAuthorship W4385262020A5076638185 @default.
- W4385262020 hasAuthorship W4385262020A5081982629 @default.
- W4385262020 hasBestOaLocation W43852620201 @default.
- W4385262020 hasConcept C109214941 @default.
- W4385262020 hasConcept C117137515 @default.
- W4385262020 hasConcept C120665830 @default.
- W4385262020 hasConcept C121332964 @default.
- W4385262020 hasConcept C168110828 @default.
- W4385262020 hasConcept C175291020 @default.
- W4385262020 hasConcept C199360897 @default.
- W4385262020 hasConcept C2779762263 @default.
- W4385262020 hasConcept C41008148 @default.
- W4385262020 hasConcept C76155785 @default.
- W4385262020 hasConceptScore W4385262020C109214941 @default.
- W4385262020 hasConceptScore W4385262020C117137515 @default.
- W4385262020 hasConceptScore W4385262020C120665830 @default.
- W4385262020 hasConceptScore W4385262020C121332964 @default.
- W4385262020 hasConceptScore W4385262020C168110828 @default.
- W4385262020 hasConceptScore W4385262020C175291020 @default.
- W4385262020 hasConceptScore W4385262020C199360897 @default.
- W4385262020 hasConceptScore W4385262020C2779762263 @default.
- W4385262020 hasConceptScore W4385262020C41008148 @default.
- W4385262020 hasConceptScore W4385262020C76155785 @default.
- W4385262020 hasLocation W43852620201 @default.
- W4385262020 hasOpenAccess W4385262020 @default.
- W4385262020 hasPrimaryLocation W43852620201 @default.
- W4385262020 hasRelatedWork W1999233082 @default.
- W4385262020 hasRelatedWork W2022477020 @default.
- W4385262020 hasRelatedWork W2065105126 @default.
- W4385262020 hasRelatedWork W2492063665 @default.
- W4385262020 hasRelatedWork W2990306029 @default.
- W4385262020 hasRelatedWork W3112271033 @default.
- W4385262020 hasRelatedWork W3129027309 @default.
- W4385262020 hasRelatedWork W3168292783 @default.
- W4385262020 hasRelatedWork W3175272150 @default.
- W4385262020 hasRelatedWork W18840729 @default.
- W4385262020 isParatext "false" @default.
- W4385262020 isRetracted "false" @default.
- W4385262020 workType "article" @default.