RAS Techniques and Instruments最新文献_第3页

Synergies between interstellar dust and heliospheric science with an Interstellar Probe 星际尘埃和日球层科学之间的协同作用与星际探测器

RAS Techniques and Instruments Pub Date : 2023-07-31 DOI: 10.1093/rasti/rzad034

V. Sterken, S. Hunziker, Kostas Dialynas, K. Herbst, Aigen Li, L. R. Baalmann, K. Scherer, P. Strub, R. Srama, M. Trieloff, M. Blanc, M. Sommer, M. Rowan‐Robinson, Harald Krüger, F. Effenberger, J. Richardson, D. Malaspina, H. Hsu, M. Horányi, Z. Sternovsky, Jonathan Slavin, J. Linsky, S. Redfield, A. Poppe, J. Szalay, Carey Lisse, E. Provornikova, M. Opher, A. Galli, F. Postberg, A. Czechowski, P. Frisch, William S Kurth, M. Shen, Thomas Chen, Zhengwei Hu, G. Stober, Ingrid Mann, N. Ligterink, Jesse A. Miller, B. Fields, J. Baggeley, P. Brandt

{"title":"Synergies between interstellar dust and heliospheric science with an Interstellar Probe","authors":"V. Sterken, S. Hunziker, Kostas Dialynas, K. Herbst, Aigen Li, L. R. Baalmann, K. Scherer, P. Strub, R. Srama, M. Trieloff, M. Blanc, M. Sommer, M. Rowan‐Robinson, Harald Krüger, F. Effenberger, J. Richardson, D. Malaspina, H. Hsu, M. Horányi, Z. Sternovsky, Jonathan Slavin, J. Linsky, S. Redfield, A. Poppe, J. Szalay, Carey Lisse, E. Provornikova, M. Opher, A. Galli, F. Postberg, A. Czechowski, P. Frisch, William S Kurth, M. Shen, Thomas Chen, Zhengwei Hu, G. Stober, Ingrid Mann, N. Ligterink, Jesse A. Miller, B. Fields, J. Baggeley, P. Brandt","doi":"10.1093/rasti/rzad034","DOIUrl":"https://doi.org/10.1093/rasti/rzad034","url":null,"abstract":"\u0000 We discuss the synergies between heliospheric and dust science, the open science questions, the technological endeavors and programmatic aspects that are important to maintain or develop in the decade to come. In particular, we illustrate how we can use interstellar dust in the solar system as a tracer for the (dynamic) heliosphere properties, and emphasize the fairly unexplored, but potentially important science question of the role of cosmic dust in heliospheric and astrospheric physics. We show that an Interstellar Probe mission with a dedicated dust suite would bring unprecedented advances to interstellar dust research, and can also contribute – through measuring dust – to heliospheric science. This can, in particular, be done well if we work in synergy with other missions inside the solar system, thereby using multiple vantage points in space to measure the dust as it ‘rolls’ into the heliosphere. Such synergies between missions inside the solar system and far out are crucial for disentangling the spatially and temporally varying dust flow. Finally, we highlight the relevant instrumentation and its suitability for contributing to finding answers to the research questions.","PeriodicalId":367327,"journal":{"name":"RAS Techniques and Instruments","volume":"224 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133945270","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: 2

A Multi-modal celestial object classification network based on two-dimensional spectrum and photometric image 基于二维光谱和光度图像的多模态天体分类网络

RAS Techniques and Instruments Pub Date : 2023-07-27 DOI: 10.1093/rasti/rzad026

M. Zhang, Junping Gao, A. Luo, Xia Jiang, Liwen Zhang, Kuang Wu, Bo Qiu

{"title":"A Multi-modal celestial object classification network based on two-dimensional spectrum and photometric image","authors":"M. Zhang, Junping Gao, A. Luo, Xia Jiang, Liwen Zhang, Kuang Wu, Bo Qiu","doi":"10.1093/rasti/rzad026","DOIUrl":"https://doi.org/10.1093/rasti/rzad026","url":null,"abstract":"\u0000 In astronomy, classifying celestial objects based on the spectral data observed by astronomical telescopes is a basic task. So far, most of the work of spectral classification is based on 1D spectral data. However, 2D spectral data, which is the predecessor of 1D spectral data, is rarely used for research. This paper proposes a multi-modal celestial classification network (MAC-Net) based on 2D spectra and photometric images that introduces an attention mechanism. In this work, all 2D spectral data and photometric data were obtained from LAMOST (the Large Sky Area Multi-Object Fiber Spectroscopic Telescope) DR6 and SDSS (Sloan Digital Sky Survey), respectively. The model extracts the features of the blue arm, red arm, and photometric images through three input branches, merges the features at the feature level and sends them to its classifiers for classification. The 2D spectral dataset used in this experiment includes 1223 galaxy spectra, 466 quasar spectra and 1202 star spectra. The same number of photometric images constitute the photometric image dataset. Experimental results show that MAC-Net can classify galaxies, quasars, and stars with a classification precision of 99.2%, 100%, and 97.6%, respectively. And the accuracy reached 98.6%, it means that the similarity between this result and the results obtained by the LAMOST template matching method is 98.6%. The results exceed the performance of the 1D spectrum classification network. At the same time, it also proves the feasibility and effectiveness of directly using 2D spectra to classify celestial bodies by using MAC-Net.","PeriodicalId":367327,"journal":{"name":"RAS Techniques and Instruments","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116471133","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

Lunar Far-Side Radio Arrays: A Preliminary Site Survey 月球远端无线电阵列:初步现场调查

RAS Techniques and Instruments Pub Date : 2023-07-12 DOI: 10.1093/rasti/rzad022

Zoe A. Le Conte, M. Elvis, Philipp A. Glaser

引用次数: 0

An S-band cryogenic phased array feed for radio astronomy 用于射电天文学的s波段低温相控阵馈电

RAS Techniques and Instruments Pub Date : 2023-07-07 DOI: 10.1093/rasti/rzad025

M. McCulloch, M. D'Cruze, K. Grainge, Michael Keith, S. Melhuish

引用次数: 0

Inspecting spectra with sound: proof-of-concept & extension to datacubes 用声音检查光谱:概念验证和扩展到数据库

RAS Techniques and Instruments Pub Date : 2023-06-16 DOI: 10.1093/rasti/rzad021

J. Trayford, C. Harrison, R. Hinz, M. Blatt, S. Dougherty, A. Girdhar

引用次数: 1

The Solar Ultra-Violet Imaging Telescope: Detector characterization and readout electronics testing 太阳紫外成像望远镜:探测器特性和读出电子测试

RAS Techniques and Instruments Pub Date : 2023-05-22 DOI: 10.1093/rasti/rzad013

S. V. M. Varma, Anurag Tyagi, Bhushan D. Joshi, Reena Yadav, Pravin A. Chordia, Ghanshyam Kumar, Sakya Sinha, M. Burse, Sreejith Padinhatteri, Rushikesh Deogaonkar, A. Ramaprakash, A. Ghosh, D. Tripathi, Janmejoy Sarkar, K. Sankarasubramanian, K. Nagaraju, K. Vadodariya, R. Kesharwani, Aafaque R. Khan, Manjunath Olekar, Mohamed Azaruddin

{"title":"The Solar Ultra-Violet Imaging Telescope: Detector characterization and readout electronics testing","authors":"S. V. M. Varma, Anurag Tyagi, Bhushan D. Joshi, Reena Yadav, Pravin A. Chordia, Ghanshyam Kumar, Sakya Sinha, M. Burse, Sreejith Padinhatteri, Rushikesh Deogaonkar, A. Ramaprakash, A. Ghosh, D. Tripathi, Janmejoy Sarkar, K. Sankarasubramanian, K. Nagaraju, K. Vadodariya, R. Kesharwani, Aafaque R. Khan, Manjunath Olekar, Mohamed Azaruddin","doi":"10.1093/rasti/rzad013","DOIUrl":"https://doi.org/10.1093/rasti/rzad013","url":null,"abstract":"\u0000 The Solar Ultraviolet Imaging Telescope (SUIT) is one of the payloads onboard the Aditya-L1 mission. It will perform full disk imaging of the Sun in the near-Ultraviolet wavelength range of 200-400 nm. This provides near-simultaneous observations of the Sun from the photosphere and chromosphere. A back-illuminated, enhanced UV Charge Coupled Device (CCD) of size 4096 (H) × 4136 (V) pixels, with a pixel size of 12 μm, is used as an imaging element in SUIT. The CCD characterization and the readout electronics development and testing were performed in-house at the Space Astronomy Group (SAG), UR Rao Satellite centre, ISRO. The test setup and procedures are explained and the measured values of various parameters including noise, dark current, gain, linearity, and cross-talk are presented in this paper. The results show a satisfactory performance from the CCD as well as the readout electronics to meet the specifications required by the SUIT payload.","PeriodicalId":367327,"journal":{"name":"RAS Techniques and Instruments","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115044734","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

Data structures for photoadsorption within the ExoMol project ExoMol项目中的光吸附数据结构

RAS Techniques and Instruments Pub Date : 2023-05-11 DOI: 10.1093/rasti/rzad014

J. Tennyson, Marco Pezzella, Jingxin Zhang, S. Yurchenko

引用次数: 0

Statistical properties of Hipparcos 2, caveats on its use, and a recalibration of the Intermediate Astrometric Data Hipparcos 2的统计特性，对其使用的注意事项，以及中间天文测量数据的重新校准

RAS Techniques and Instruments Pub Date : 2023-05-05 DOI: 10.1093/rasti/rzad011

G. M. Brandt, D. Michalik, Timothy D. Brandt

{"title":"Statistical properties of Hipparcos 2, caveats on its use, and a recalibration of the Intermediate Astrometric Data","authors":"G. M. Brandt, D. Michalik, Timothy D. Brandt","doi":"10.1093/rasti/rzad011","DOIUrl":"https://doi.org/10.1093/rasti/rzad011","url":null,"abstract":"\u0000 We revisit the Hipparcos 2007 re-reduction and find improvements to the catalog by leveraging Gaia EDR3. We show that including a constant residual offset and additional dispersion (two free parameters in total) in the Hipparcos 2007 IAD creates a new catalog with significantly better agreement with Gaia EDR3. The astrometric parameters, after recalibration, have z-scores that follow a unit-Gaussian when measured against Gaia EDR3 values. We have expanded the Python astrometry tool, htof, to recalibrate the IAD on-the-fly. On a second front, we find that a merged set of IAD from the 1997 and 2007 Hipparcos reductions is not possible in an internally consistent manner. This can be understood if Hipparcos 2007 is an improved, but overfit, model to the underlying along-scan data. For this reason, we recommend using the recalibrated Hipparcos 2007 astrometric parameters, or those from the Hipparcos-Gaia Catalog of Accelerations – because the signatures of overfitting are calibrated out. We advise caution in fitting orbits to the IAD from either Hipparcos 2 as-published or the recalibrated version presented here.","PeriodicalId":367327,"journal":{"name":"RAS Techniques and Instruments","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126434601","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

Searching for Quasi-Periodic Eruptions using machine learning 用机器学习搜索准周期性喷发

RAS Techniques and Instruments Pub Date : 2023-05-05 DOI: 10.1093/rasti/rzad015

R. Webbe, A. Young

引用次数: 0

Overcomplete tomography: A novel approach to imaging 过完全断层扫描:一种新的成像方法

RAS Techniques and Instruments Pub Date : 2023-04-28 DOI: 10.1093/rasti/rzad010

B. Turunçtur, A. Valentine, M. Sambridge

{"title":"Overcomplete tomography: A novel approach to imaging","authors":"B. Turunçtur, A. Valentine, M. Sambridge","doi":"10.1093/rasti/rzad010","DOIUrl":"https://doi.org/10.1093/rasti/rzad010","url":null,"abstract":"\u0000 Regularised least-squares tomography offers a straightforward and efficient imaging method and has seen extensive application across various fields. However, it has a few drawbacks, such as (i) the regularisation imposed during the inversion tends to give a smooth solution, which will fail to reconstruct a multi-scale model well or detect sharp discontinuities, (ii) it requires finding optimum control parameters, (iii) it does not produce a sparse solution. This paper introduces ‘overcomplete tomography’, a novel imaging framework that allows high-resolution recovery with relatively few data points. We express our image in terms of an overcomplete basis, allowing the representation of a wide range of features and characteristics. Following the insight of ‘compressive sensing’, we regularise our inversion by imposing a penalty on the L1 norm of the recovered model, obtaining an image that is sparse relative to the overcomplete basis. We demonstrate our method with a synthetic and a real X-ray tomography example. Our experiments indicate that we can reconstruct a multi-scale model from only a few observations. The approach may also assist interpretation, allowing images to be decomposed into (for example) ‘global’ and ‘local’ structures. The framework presented here can find application across a wide range of fields, including engineering, medical and geophysical tomography.","PeriodicalId":367327,"journal":{"name":"RAS Techniques and Instruments","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124231632","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