Journal of Astronomical Instrumentation最新文献

Design of an Ultra-Wideband Antenna Feed and Reflector for use in Hydrogen Intensity Mapping Interferometers 用于氢强度测绘干涉仪的超宽带天线馈源和反射器的设计

Journal of Astronomical Instrumentation Pub Date : 2023-10-27 DOI: 10.1142/s2251171724500041

John Podczerwinski, Peter Timbie

引用次数: 0

Low Complexity Radio Frequency Interference Mitigation for Radio Astronomy Using Large Antenna Array 基于大型天线阵列的射电天文学低复杂度射频干扰抑制

Journal of Astronomical Instrumentation Pub Date : 2023-10-27 DOI: 10.1142/s225117172450003x

Zaid Bin Tariq, Teviet Creighton, Louis P. Dartez, Naofal Al-Dhahir, Murat Torlak

引用次数: 0

The Effects of the Local Environment on a Compact Radio Interferometer I: Cross-coupling in the Tianlai Dish Pathfinder Array 局部环境对小型射电干涉仪的影响ⅰ:天来碟探路者阵列的交叉耦合

Journal of Astronomical Instrumentation Pub Date : 2023-10-13 DOI: 10.1142/s2251171724500028

Juhun Kwak, John Podczerwinski, Peter Timbie, Reza Ansari, John Marriner, Albert Stebbins, Fengquan Wu, Haotian Cao, Xuelei Chen, Kai He, Jixia Li, Shijie Sun, Jiacong Zhu

{"title":"The Effects of the Local Environment on a Compact Radio Interferometer I: Cross-coupling in the Tianlai Dish Pathfinder Array","authors":"Juhun Kwak, John Podczerwinski, Peter Timbie, Reza Ansari, John Marriner, Albert Stebbins, Fengquan Wu, Haotian Cao, Xuelei Chen, Kai He, Jixia Li, Shijie Sun, Jiacong Zhu","doi":"10.1142/s2251171724500028","DOIUrl":"https://doi.org/10.1142/s2251171724500028","url":null,"abstract":"The visibilities measured by radio astronomical interferometers include non-astronomical correlated signals that arise from the local environment of the array. These correlated signals are especially important in compact arrays such as those under development for 21,cm intensity mapping. The amplitudes of the contaminated visibilities can exceed the expected 21,cm signal and represent a significant systematic effect. We study the receiver noise radiated by antennas in compact arrays and develop a model for how it couples to other antennas. We apply the model to the Tianlai Dish Pathfinder Array (TDPA), a compact array of 16, 6-m dish antennas. The coupling model includes electromagnetic simulations, measurements with a network analyzer, and measurements of the noise of the receivers. We compare the model to drift-scan observations with the array and set requirements on the level of antenna cross-coupling for 21,cm intensity mapping instruments. We find that for the TDPA, cross-coupling would have to be reduced by TBD orders of magnitude in order to contribute negligibly to the visibilities.","PeriodicalId":45132,"journal":{"name":"Journal of Astronomical Instrumentation","volume":"127 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135917882","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

Interferometric determination for cosmological and stellar phenomena 宇宙和恒星现象的干涉测定

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2023-09-05 DOI: 10.1142/s2251171724500016

P. B. Lerner, P. H. Cutler, N. Miskovsky, T. E. Sullivan, A. Mayer

引用次数: 0

DMD based Multi-Object Spectrograph for INdian Spectroscopic and Imaging Space Telescope: INSIST 基于DMD的印度光谱和成像空间望远镜多目标摄谱仪:坚持

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2023-08-23 DOI: 10.1142/s2251171723500125

S. Sriram, V. Valsan, A. Hoodati, A. Subramaniam, G. Maheswar

引用次数: 0

Calibration of Spectropolarimetry Package for Visible Emission Line Coronagraph (VELC) on board Aditya-L1 Mission Aditya-L1任务可见光发射线日冕仪(VELC)分光偏振仪包的校准

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2023-08-23 DOI: 10.1142/s2251171723500113

Venkata Suresh Narra, Bhavana S. Hegde, Utkarsha Dasamantarao, Natarajan Venkatasubramanian, Pawan Kumar Somasundaram, Umesh Kamath Padhavu, Raghavendra Prasad Budihal

引用次数: 0

A compact cryogenic configurable slit unit for a multi-object infrared spectrograph: Design and Development of a prototype at TIFR 用于多目标红外光谱仪的紧凑型低温可配置狭缝装置：TIFR原型的设计和开发

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2023-07-28 DOI: 10.1142/s2251171723500101

P. Madhwani, A. Kutty, B. Mookerjea, J. Parmar, V. Kurhade, S. D’costa, P. Manoj, A. Surya

引用次数: 1

The Synthesis Convolver 合成卷积器

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2023-07-26 DOI: 10.1142/s225117172350006x

J. Bunton

{"title":"The Synthesis Convolver","authors":"J. Bunton","doi":"10.1142/s225117172350006x","DOIUrl":"https://doi.org/10.1142/s225117172350006x","url":null,"abstract":"A system, the synthesis convolver, is described that can process the output of an analysis filter bank and: • Reconstruct the analysis filter bank input signal, • Implement continuous convolution on the reconstructed signal, and • Resample the reconstructed signal to different sample rates. The synthesis convolver combines the capabilities of a synthesis filter bank and a continuous convolver. The synthesis convolver is based on earlier work but improves upon it, adding convolution and resampling. As well as reconstructing filterbank data, convolution allows dechirping of pulsar signals and resampling allows synthesized data to conform to the VLBI VDIF standard. The spectral overlap-add approach described, compared to earlier work, reduces errors and is more robust to channel gain errors. The system uses windows with smoothed or apodized edges, with the classical Tukey window being used previously. Here the Tukey window is generalized leading to a class of apodized windows. This class of windows is explored and one is found that is close to optimal in all conditions and can reduce errors by up to 40[Formula: see text]dB compared to an equivalent Tukey window. Achievable aliasing errors are lower than those of a standard polyphase synthesis filter bank. The synthesis convolver provides a high quality and versatile replacement for polyphase synthesis filter banks.","PeriodicalId":45132,"journal":{"name":"Journal of Astronomical Instrumentation","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47734401","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

Statistical Prediction of [CII] Observations by Constructing Probability density Functions using SOFIA, Herschel, and Spitzer Observations 利用SOFIA、Herschel和Spitzer观测构建概率密度函数对[CII]观测进行统计预测

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2023-07-04 DOI: 10.1142/S2251171723500071

Youngchwa Seo, K. Willacy, U. Rebbapragada

{"title":"Statistical Prediction of [CII] Observations by Constructing Probability density Functions using SOFIA, Herschel, and Spitzer Observations","authors":"Youngchwa Seo, K. Willacy, U. Rebbapragada","doi":"10.1142/S2251171723500071","DOIUrl":"https://doi.org/10.1142/S2251171723500071","url":null,"abstract":"We present a statistical algorithm for predicting the [CII] emission from Herschel and Spitzer continuum images using probability density functions between the [CII] emission and continuum emission. The [CII] emission at 158 $mu$m is a critical tracer in studying the life cycle of interstellar medium and galaxy evolution. Unfortunately, its frequency is in the far infrared (FIR), which is opaque through the troposphere and cannot be observed from the ground except for highly red-shifted sources (z $gtrsim$ 2). Typically [CII] observations of closer regions have been carried out using suborbital or space observatories. Given the high cost of these facilities and limited time availability, it is important to have highly efficient observations/operations in terms of maximizing science returns. This requires accurate prediction of the strength of emission lines and, therefore, the time required for their observation. However, [CII] emission has been hard to predict due to a lack of strong correlations with other observables. Here we adopt a new approach to making accurate predictions of [CII] emission by relating this emission simultaneously to several tracers of dust emission in the same region. This is done using a statistical methodology utilizing probability density functions (PDFs) among [CII] emission and Spitzer IRAC and Herschel PACS/SPIRE images. Our test result toward a star-forming region, RCW 120, demonstrates that our methodology delivers high-quality predictions with less than 30% uncertainties over 80% of the entire observation area, which is more than sufficient to test observation feasibility and maximize science return. The {it pickle} dump files storing the PDFs and trained neural network module are accessible upon request and will support future far-infrared missions, for example, GUSTO and FIR Probe.","PeriodicalId":45132,"journal":{"name":"Journal of Astronomical Instrumentation","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2023-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48189879","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

4K×4K CCD Imager for the 3.6m DOT: Recent up-gradations and results 4K×4K用于360万DOT的CCD成像仪:最近的升级和结果

IF 1.3

Journal of Astronomical Instrumentation Pub Date : 2023-06-23 DOI: 10.1142/s2251171722400098

S. Pandey, Amit Kumar, B. Reddy, S. Yadav, N. Nanjappa, A. Aryan, Rahul Gupta, N. Panwar, R. Yadav

引用次数: 0