Monthly Notices of the Royal Astronomical Society最新文献_第8页

Correction to: Modelling the seasonal cycle of Uranus's colour and magnitude, and comparison with Neptune 更正：天王星颜色和星等的季节周期模型以及与海王星的比较

Monthly Notices of the Royal Astronomical Society Pub Date : 2024-02-07 DOI: 10.1093/mnras/stae304

引用次数: 0

Stark Broadening Data for Ultraviolet lines of Ni V 镍五紫外线的斯塔克展宽数据

Monthly Notices of the Royal Astronomical Society Pub Date : 2024-02-07 DOI: 10.1093/mnras/stae391

R. Hamdi, S. Sahal-Bréchot, M. Dimitrijević, H. Elabidi

引用次数: 0

Stark Broadening Data for Ultraviolet lines of Ni V 镍五紫外线的斯塔克展宽数据

Monthly Notices of the Royal Astronomical Society Pub Date : 2024-02-07 DOI: 10.1093/mnras/stae391

R. Hamdi, S. Sahal-Bréchot, M. Dimitrijević, H. Elabidi

引用次数: 0

Observations of interstellar scattering of six pulsars using Polish LOFAR station PL611 利用波兰 LOFAR 站 PL611 对六颗脉冲星的星际散射进行观测

Monthly Notices of the Royal Astronomical Society Pub Date : 2024-02-07 DOI: 10.1093/mnras/stae399

A. Filothodoros, W. Lewandowski, Jarosłlaw Kijak, Bartosz Śmierciak, Krzysztof Chyży, Leszek Błlaszkiewicz Andrzej Krankowski

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引用次数: 0

Correction to: Modelling the seasonal cycle of Uranus's colour and magnitude, and comparison with Neptune 更正：天王星颜色和星等的季节周期模型以及与海王星的比较

Monthly Notices of the Royal Astronomical Society Pub Date : 2024-02-07 DOI: 10.1093/mnras/stae304

引用次数: 0

Observations of interstellar scattering of six pulsars using Polish LOFAR station PL611 利用波兰 LOFAR 站 PL611 对六颗脉冲星的星际散射进行观测

Monthly Notices of the Royal Astronomical Society Pub Date : 2024-02-07 DOI: 10.1093/mnras/stae399

A. Filothodoros, W. Lewandowski, Jarosłlaw Kijak, Bartosz Śmierciak, Krzysztof Chyży, Leszek Błlaszkiewicz Andrzej Krankowski

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引用次数: 0

Detecting non-thermal emission in a solar microflare using nested sampling 利用嵌套采样检测太阳微耀斑中的非热辐射

Monthly Notices of the Royal Astronomical Society Pub Date : 2024-02-06 DOI: 10.1093/mnras/stae348

K. Cooper, I. Hannah, L. Glesener, B. Grefenstette

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引用次数: 0

Image based automatic wind velocity profiler for adaptive optics 基于图像的自适应光学自动风速剖面仪

Monthly Notices of the Royal Astronomical Society Pub Date : 2024-02-06 DOI: 10.1093/mnras/stae326

Sebastian J Diaz, Cristian Tejos, Andres Guesalaga

{"title":"Image based automatic wind velocity profiler for adaptive optics","authors":"Sebastian J Diaz, Cristian Tejos, Andres Guesalaga","doi":"10.1093/mnras/stae326","DOIUrl":"https://doi.org/10.1093/mnras/stae326","url":null,"abstract":"\u0000 Adaptive optics (AO) systems correct optical phase aberrations of the incoming light generated by the atmosphere. To do so simultaneous estimators of the atmospheric turbulence parameters are required. For the family of wide-field AO systems (WFAO), this information must be stratified in altitude. Among these vectorized estimations, wind profiling in altitude is needed for the reduction of temporal errors in AO loops or for the estimation of turbulence coherence time. This paper proposes a turbulence wind profiler called image processing based peak tracking algorithm (IPTA). IPTA is an image-processing based approach that automatically and reliably estimates wind velocity for several turbulent layers along the line of sight. The estimation of each wind layer is achieved by tracking peaks produced in cross-correlation maps from pairs of wavefront sensors (WFSs) slopes using the technique known as SLODAR (slope detection and ranging). Results for simulated and on-sky WFS datasets demonstrate that IPTA outperforms one of the state of the art wind profiler methods (the profiler covariance parametrization of wind velocity (CAW)) in terms of accuracy and speed. Results also show that, in terms of execution time, our method scales better when the number of WFS lenslets is increased. Being an open source and reliable tool, we believe IPTA can be a useful wind profiler for the adaptive optics community.","PeriodicalId":506975,"journal":{"name":"Monthly Notices of the Royal Astronomical Society","volume":"81 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139858358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Detecting non-thermal emission in a solar microflare using nested sampling 利用嵌套采样检测太阳微耀斑中的非热辐射

Monthly Notices of the Royal Astronomical Society Pub Date : 2024-02-06 DOI: 10.1093/mnras/stae348

K. Cooper, I. Hannah, L. Glesener, B. Grefenstette

{"title":"Detecting non-thermal emission in a solar microflare using nested sampling","authors":"K. Cooper, I. Hannah, L. Glesener, B. Grefenstette","doi":"10.1093/mnras/stae348","DOIUrl":"https://doi.org/10.1093/mnras/stae348","url":null,"abstract":"\u0000 Microflares are energetically smaller versions of solar flares, demonstrating the same processes of plasma heating and particle acceleration. However, it remains unclear down to what energy scales this impulsive energy release continues, which has implications for how the solar atmosphere is heated. The heating and particle acceleration in microflares can be studied through their X-ray emission, finding predominantly thermal emission at lower energies; however, at higher energies it can be difficult to distinguish whether the emission is due to hotter plasma and/or accelerated elections. We present the first application of nested sampling to solar flare X-ray spectra, an approach which provides a quantitative degree of confidence for one model over another. We analyse NuSTAR X-ray observations of a small active region microflare (A0.02 GOES/XRS class equivalent) that occurred on 2021 November 17, with a new Python package for spectral fitting, sunkit-spex, to compute the parameter posterior distributions and the evidence of different models representing the higher energy emission as due to thermal or non-thermal sources. Calculating the Bayes factor, we show there is significantly stronger evidence for the higher energy microflare emission to be produced by non-thermal emission from flare accelerated electrons than by an additional hot thermal source. Qualitative confirmation of this non-thermal source is provided by the lack of hotter (10 MK) emission in SDO/AIA’s EUV data. The nested sampling approach used in this paper has provided clear support for non-thermal emission at the level of 3× 1024 erg s−1 in this tiny microflare.","PeriodicalId":506975,"journal":{"name":"Monthly Notices of the Royal Astronomical Society","volume":"329 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139799045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Image based automatic wind velocity profiler for adaptive optics 基于图像的自适应光学自动风速剖面仪

Monthly Notices of the Royal Astronomical Society Pub Date : 2024-02-06 DOI: 10.1093/mnras/stae326

Sebastian J Diaz, Cristian Tejos, Andres Guesalaga

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引用次数: 0