Journal of Astronomical Instrumentation最新文献_第4页

Physical Considerations for an Intercept Mission to a 1I/'Oumuamua-like Interstellar Object 拦截类oumuamua星际物体的物理考虑

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2022-11-03 DOI: 10.1142/s2251171723400019

A. Siraj, A. Loeb, A. Moro-Martin, Mark Elowitz, A. White, W. Watters, G. Melnick, Richard Cloete, J. Grindlay, F. Laukien

{"title":"Physical Considerations for an Intercept Mission to a 1I/'Oumuamua-like Interstellar Object","authors":"A. Siraj, A. Loeb, A. Moro-Martin, Mark Elowitz, A. White, W. Watters, G. Melnick, Richard Cloete, J. Grindlay, F. Laukien","doi":"10.1142/s2251171723400019","DOIUrl":"https://doi.org/10.1142/s2251171723400019","url":null,"abstract":"In this paper, we review some of the extant literature on the study of interstellar objects (ISOs). With the forthcoming Vera C. Rubin Telescope and Legacy Survey of Space and Time (LSST), we ﬁnd that 0 . 38 − 84 ‘Oumuamua-like interstellar objects are expected to be detected in the next 10 years, with 95% conﬁdence. The feasibility of a rendezvous trajectory has been demonstrated in previous work. In this paper, we investigate the requirements for a rendezvous mission with the primary objective of producing a resolved image of an interstellar object. We outline the rendezvous distances necessary as a function of resolution elements and object size. We expand upon current population synthesis models to account for the size dependency on the detection rates for reachable interstellar objects. We assess the trade-oﬀ between object diameter and occurrence rate, and conclude that objects with the size range between a third of the size and the size of ‘Oumuamua will be optimal targets for an imaging rendezvous. We also discuss expectations for surface properties and spectral features of interstellar objects, as well as the beneﬁts of various spacecraft storage locations.","PeriodicalId":45132,"journal":{"name":"Journal of Astronomical Instrumentation","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43149505","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

Low-cost, Low-loss, Ultra-wideband Compact Feed for Interferometric Radio Telescopes 用于干涉射电望远镜的低成本，低损耗，超宽带紧凑型馈电

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2022-10-14 DOI: 10.1142/s2251171723500083

Vincent MacKay, Mark Lai, P. Shmerko, D. Wulf, L. Belostotski, K. Vanderlinde

{"title":"Low-cost, Low-loss, Ultra-wideband Compact Feed for Interferometric Radio Telescopes","authors":"Vincent MacKay, Mark Lai, P. Shmerko, D. Wulf, L. Belostotski, K. Vanderlinde","doi":"10.1142/s2251171723500083","DOIUrl":"https://doi.org/10.1142/s2251171723500083","url":null,"abstract":"We have developed, built, and tested a new feed design for interferometric radio telescopes with\"large-$N$, small-$D$\"designs. Those arrays require low-cost and low-complexity feeds for mass production on reasonable timescales and budgets, and also require those feeds to be compact to minimize obstruction of the dishes, along with having ultra wide bands of operation for most current and future science goals. The feed presented in this paper modifies the exponentially tapered slot antenna (Vivaldi) and quad-ridged flared horn antenna designs by having an oversized backshort, a novel method of maintaining a small size that is well-suited for deeper dishes ($f/Dleq 0.25$). It is made of laser cut aluminum and printed circuit boards, such that it is inexpensive ($lesssim$ 75 USD per feed in large-scale production) and quick to build; it has a 5:1 frequency ratio, and its size is approximately a third of its longest operating wavelength. We present the science and engineering constraints that went into design decisions, the development and optimization process, and the simulated performance. A version of this feed design was optimized and built for the Canadian Hydrogen Observatory and Radio-transient Detector (CHORD) prototypes. When simulated on CHORD's very deep dishes ($f/D=0.21$) and with CHORD's custom first stage amplifiers, the on-sky system temperature $T_mathrm{sys}$ of the complete receiving system from dish to digitizer remains below 30 K over most of the 0.3-1.5 GHz band, and maintains an aperture efficiency $eta_mathrm{A}$ between 0.4 and 0.6. The entire receiving chain operates at ambient temperature. The feed is designed to slightly under-illuminate the CHORD dishes, in order to minimize coupling between array elements and spillover.","PeriodicalId":45132,"journal":{"name":"Journal of Astronomical Instrumentation","volume":"55 5","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41258360","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

Astrometric and Photometric Standard Candidates for the Upcoming 4-m International Liquid Mirror Telescope Survey 即将到来的4米国际液镜望远镜巡天的天体测量和光度标准候选者

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2022-10-11 DOI: 10.1142/s2251171722400013

Naveen Dukiya, K. Misra, B. Pradhan, Vibhore Negi, B. Ailawadhi, B. Kumar, P. Hickson, J. Surdej

{"title":"Astrometric and Photometric Standard Candidates for the Upcoming 4-m International Liquid Mirror Telescope Survey","authors":"Naveen Dukiya, K. Misra, B. Pradhan, Vibhore Negi, B. Ailawadhi, B. Kumar, P. Hickson, J. Surdej","doi":"10.1142/s2251171722400013","DOIUrl":"https://doi.org/10.1142/s2251171722400013","url":null,"abstract":"The International Liquid Mirror Telescope (ILMT) is a 4-m class survey telescope that has recently achieved first light and is expected to swing into full operations by January 1, 2023. It scans the sky in a fixed [Formula: see text] wide strip centered at the declination of [Formula: see text] and works in Time Delay Integration (TDI) mode. We present a full catalog of sources in the ILMT strip that can serve as astrometric calibrators. The characteristics of the sources for astrometric calibration are extracted from Gaia EDR3 as it provides a very precise measurement of astrometric properties such as RA ([Formula: see text]), Dec ([Formula: see text]), parallax ([Formula: see text]), and proper motions ([Formula: see text] & [Formula: see text]). We have crossmatched the Gaia EDR3 with SDSS DR17 and PanSTARRS-1 (PS1) and supplemented the catalog with apparent magnitudes of these sources in [Formula: see text], and [Formula: see text] filters. We also present a catalog of spectroscopically confirmed white dwarfs with Sloan Digital Sky Survey (SDSS) magnitudes that may serve as photometric calibrators. The catalogs generated are stored in an SQLite database for query-based access. We also report the offsets in equatorial positions compared to Gaia for an astrometrically calibrated TDI frame observed with the ILMT.","PeriodicalId":45132,"journal":{"name":"Journal of Astronomical Instrumentation","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45029985","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: 3

Overview of The Galileo Project 伽利略计划概述

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2022-08-02 DOI: 10.1142/s2251171723400032

A. Loeb

引用次数: 3

Probing the New Generation Geodetic Radio Telescopes for FRB Observations 探索新一代大地射电望远镜的快速射电暴观测

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2022-06-24 DOI: 10.1142/s2251171722500155

S. Kurdubov, D. Marshalov

引用次数: 0

First light of the Integral Field Unit of GRIS on the GREGOR solar telescope GREGOR太阳望远镜上GRIS积分场单元的初光

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2022-06-07 DOI: 10.1142/S2251171722500143

C. Dominguez-Tagle, M. Collados, R. López, J. J. V. Cedillo, M. Esteves, O. Grassin, N. Vega, Á. Mato, J. Quintero, H. Rodriguez, S. Regalado, F. G. I. D. A. D. Canarias, D. Astrof́isica, U. L. Laguna, Leibniz-Institut fur Sonnenphysik

{"title":"First light of the Integral Field Unit of GRIS on the GREGOR solar telescope","authors":"C. Dominguez-Tagle, M. Collados, R. López, J. J. V. Cedillo, M. Esteves, O. Grassin, N. Vega, Á. Mato, J. Quintero, H. Rodriguez, S. Regalado, F. G. I. D. A. D. Canarias, D. Astrof́isica, U. L. Laguna, Leibniz-Institut fur Sonnenphysik","doi":"10.1142/S2251171722500143","DOIUrl":"https://doi.org/10.1142/S2251171722500143","url":null,"abstract":"An Integral Field Unit (IFU) based on image-slicers has been added to the GREGOR Infrared Spectrograph (GRIS). This upgrade to the instrument makes possible 2D spectropolarimetry in the near-infrared by simultaneously recording the full Stokes profiles of spectral lines (in a given spectral interval) at all the points in the field of view. It provides high-cadence spectropolarimetric observations at the instrument's high spatial resolution and high polarization sensitivity at the GREGOR solar telescope. The IFU is ideal for observing the polarized spectrum of fast-evolving solar features at high spatial and spectral resolutions. The high observing cadence opens the possibility of time-series observations. The analysis of observations to this level of accuracy is essential for understanding the complex dynamics and interactions of solar plasma and magnetic fields. The image slicer of the IFU has eight slices of width 100 micron, covering a total field of view of 6\"x 3\". It was designed and built within the framework of the European projects SOLARNET and GREST, as a prototype for future instruments of the European Solar Telescope (EST) and was integrated into GRIS. After two commissioning campaigns in 2017 and 2018, the IFU was finally installed at the end of September 2018 and offered to all observers who use the telescope.","PeriodicalId":45132,"journal":{"name":"Journal of Astronomical Instrumentation","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47302176","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: 8

A preliminary plan to quickly restore utility to the Arecibo 305m telescope 初步计划迅速恢复阿雷西博305米望远镜的功能

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2022-05-27 DOI: 10.1142/s225117172250012x

D. Ferguson, J. Breakall, P. Bernhardt, Felix Fernandez, C. Brum, Alfredo Iii Santoni-Ruiz, R. Kerr, Robert L. Williams II

引用次数: 1

Exoplanet detection with Genesis 用创世纪探测系外行星

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2022-05-11 DOI: 10.1142/s2251171722500118

K. Visser, B. Bosma, E. Postma

引用次数: 1

Experimental Validation of a Novel Concept to Reduce Optical Surface Wave Front Errors by Using Deformable Bushes at Opto-Mechanical Interfaces 利用可变形衬套减小光机械界面表面波前误差新概念的实验验证

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2022-03-02 DOI: 10.1142/s2251171722500039

S. Nagabhushana, B. R. Prasad, S. Nagesh, Suresh Venkata Nara, D. Sandeep, P. Kamath, Shalab Misra, Bhavana S. Hegde, D. Utkarsha, M. K. Sinha, S. Kathiravan, V. Natarajan, S. P. Kumar, Amit Kumar

{"title":"Experimental Validation of a Novel Concept to Reduce Optical Surface Wave Front Errors by Using Deformable Bushes at Opto-Mechanical Interfaces","authors":"S. Nagabhushana, B. R. Prasad, S. Nagesh, Suresh Venkata Nara, D. Sandeep, P. Kamath, Shalab Misra, Bhavana S. Hegde, D. Utkarsha, M. K. Sinha, S. Kathiravan, V. Natarajan, S. P. Kumar, Amit Kumar","doi":"10.1142/s2251171722500039","DOIUrl":"https://doi.org/10.1142/s2251171722500039","url":null,"abstract":"One of the major objectives of the optomechanics is to support large optics required for the purpose and also to maintain high dynamic stability in operation. This requirement calls for more number of supports, to support large optics. While addressing this issue, the mounting system tends to become non-kinematic and distorts the optical surface and leads to poor image quality. The distorted optical surfaces bring in increased RMS surface wavefront errors which will result in poor image quality. In this context, a new concept is proposed in our previous publication (Nagabhushana et al., 2021) which involves introduction of deformable bushes at the optomechanical interfaces. These are deformed by applied clamping forces and also enabling all degrees of freedom (DOF) to be arrested. This also ensures that the clamping force in axial DOF is limited to a minimal value. This technique enables to arrest of axial DOF without exerting the clamping force on the optomechanical assembly there by reduces optical aberrations and improves the mounting system’s dynamic stability. This is because deformable bushes absorb all the clamping forces and the strain has no impact on the mount and therefore does not lead deformation of the optical surface. The clamping forces are simulated by Finite Element (FE) methods. Further, in this paper, the concept is verified and validated by experiments. The simulation results are observed to be in close correlation with experiment results. Improved stability is also observed by additional constraints introduced to optomechanical mounts with no compromise in wavefront errors.","PeriodicalId":45132,"journal":{"name":"Journal of Astronomical Instrumentation","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47520903","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

Evaluation of Controllers and Development of a new in-house Controller for the Teledyne HxRG Focal Plane Array for the IRSIS satellite payload 用于IRSIS卫星有效载荷的Teledyne HxRG焦平面阵列控制器的评估和新型内部控制器的开发

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2022-03-01 DOI: 10.1142/s225117172250009x

M. B. Naik, D. Ojha, S. Ghosh, P. Manoj, J. Ninan, S. Ghosh, S. D’costa, S. Poojary, S. Bhagat, P. Sandimani, H. Shah, R. Jadhav, S. Gharat, G. Meshram, B. G. Bagade

{"title":"Evaluation of Controllers and Development of a new in-house Controller for the Teledyne HxRG Focal Plane Array for the IRSIS satellite payload","authors":"M. B. Naik, D. Ojha, S. Ghosh, P. Manoj, J. Ninan, S. Ghosh, S. D’costa, S. Poojary, S. Bhagat, P. Sandimani, H. Shah, R. Jadhav, S. Gharat, G. Meshram, B. G. Bagade","doi":"10.1142/s225117172250009x","DOIUrl":"https://doi.org/10.1142/s225117172250009x","url":null,"abstract":"The Infrared Astronomy Group (Department of Astronomy and Astrophysics) at Tata Institute of Fundamental Research (TIFR) is presently developing controllers for the Teledyne HxRG Focal Plane Arrays (FPAs) to be used on board the Infrared Spectroscopic Imaging Survey (IRSIS) satellite payload. In this manuscript we discuss the results of our tests with different FPA controllers like the Astronomical Research Cameras (ARC) controller, Teledyne’s SIDECAR ASIC as well as our new in-house designed Array controller. As part of the development phase of the IRSIS instrument, which is an optical fibre based Integral Field Unit (IFU) Near-Infrared (NIR) Spectrometer, a laboratory model with limited NIR bandwidth was built which consisted of various subsystems like a Ritchey-Chretien (RC) 30 cm telescope, optical fibre IFU, spectrometer optics, and the Teledyne H2RG detector module. We discuss the various developments during the building and testing of the IRSIS laboratory model and the technical aspects of the prototype in-house H2RG controller.","PeriodicalId":45132,"journal":{"name":"Journal of Astronomical Instrumentation","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2022-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45505182","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