HiFAST: An H I data calibration and imaging pipeline for the FAST IV: The stray-radiation correction

doi:10.1088/1674-1056/ae4b27

中国物理B ›› 2026, Vol. 35 ›› Issue (5): 59501-059501.doi: 10.1088/1674-1056/ae4b27

HiFAST: An H I data calibration and imaging pipeline for the FAST IV: The stray-radiation correction

Qing-Ze Chen(陈箐泽)^1,3,†, Jie Wang(王杰)^1,2,3, Ying-Jie Jing(景英杰)¹, Li-Gang Hou(侯立刚)¹, Chen Xu(徐晨)^1,3, Tian-Tian Liang(梁甜甜)^1,3, Xu-Yang Gao(高旭阳)^1,4, Jin-Lin Han(韩金林)^1,4, Zi-Ming Liu(刘孜铭)¹, Bin Liu(刘彬)¹, Chuan-Peng Zhang(张传鹏)¹, Heng-Qian Gan(甘恒谦)¹, Ming Zhu(朱明)¹, Yan Zhu(朱岩)¹, and Peng Jiang(姜鹏)^1,4

1 National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China;
2 Institute for Frontiers in Astronomy and Astrophysics, Beijing Normal University, Beijing 102206, China;
3 School of Astronomy and Space Science, University of Chinese Academy of Sciences, Beijing 100049, China;
4 CAS Key Laboratory of FAST, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100101, China

收稿日期:2025-12-15 修回日期:2026-02-09 接受日期:2026-02-27 发布日期:2026-04-29
通讯作者: Qing-Ze Chen,E-mail:chenqz@bao.ac.cn E-mail:chenqz@bao.ac.cn
基金资助:
This work was supported by the National Key Research and Development Program of China (Grant Nos. 2022YFA1602901 and 2023YFA1608204), the National SKA Programme of China (Grant No. 2022SKA0110201), the National Natural Science Foundation of China (Grant Nos. 11873051, 11988101, 12033008, 12041305, 12125302, 12173016, and 12203065), the CAS Project for Young Scientists in Basic Research (Grant No. YSBR-062), the K.C. Wong Education Foundation, and the Scientific Research Grants from the China Manned Space Project.

HiFAST: An H I data calibration and imaging pipeline for the FAST IV: The stray-radiation correction

1 National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China;
2 Institute for Frontiers in Astronomy and Astrophysics, Beijing Normal University, Beijing 102206, China;
3 School of Astronomy and Space Science, University of Chinese Academy of Sciences, Beijing 100049, China;
4 CAS Key Laboratory of FAST, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100101, China

Received:2025-12-15 Revised:2026-02-09 Accepted:2026-02-27 Published:2026-04-29
Contact: Qing-Ze Chen,E-mail:chenqz@bao.ac.cn E-mail:chenqz@bao.ac.cn
Supported by:
This work was supported by the National Key Research and Development Program of China (Grant Nos. 2022YFA1602901 and 2023YFA1608204), the National SKA Programme of China (Grant No. 2022SKA0110201), the National Natural Science Foundation of China (Grant Nos. 11873051, 11988101, 12033008, 12041305, 12125302, 12173016, and 12203065), the CAS Project for Young Scientists in Basic Research (Grant No. YSBR-062), the K.C. Wong Education Foundation, and the Scientific Research Grants from the China Manned Space Project.

摘要/Abstract

摘要： Stray radiation is a considerable challenge for radio telescopes, requiring careful assessment of its effects. This is crucial when the strong background flux from side lobes significantly affects the total flux, especially for extended sources. In this study, we introduced the beam pattern of the L-band receiver on the Five-hundred-meter Aperture Spherical Telescope (FAST), covering various frequencies based on recent observations. We discovered that the main beam efficiency of all beams exceeds 90 % throughout the L band frequencies, with efficiency decreasing slowly as frequency increases. Subsequently, we developed a module to mitigate stray radiation effects, incorporating it into FAST's standard H\textsc{i} data reduction process, referred to as HiFAST. Our analysis shows that side lobe flux's influence, particularly for extended sources with significant surface density gradients, necessitates detailed evaluation. Corrections for the extended M33 galaxy can reach up to 20 %. Moreover, the pattern data presented here is vital for studying H\textsc{i} intensity maps at high redshift. The module, along with HiFAST and beam pattern data across 15 frequency bins, can be accessed at \href{https://hifast.readthedocs.io}{https://hifast.readthedocs.io}. The datasets of beam pattern presented in this paper are openly available at \href{https://doi.org/10.57760/sciencedb.j00113.00266}{https://doi.org/10.57760/sciencedb.j00113.00266}.

关键词: radio lines, galaxies-radio continuum, galaxies-methods, data analysis

Abstract: Stray radiation is a considerable challenge for radio telescopes, requiring careful assessment of its effects. This is crucial when the strong background flux from side lobes significantly affects the total flux, especially for extended sources. In this study, we introduced the beam pattern of the L-band receiver on the Five-hundred-meter Aperture Spherical Telescope (FAST), covering various frequencies based on recent observations. We discovered that the main beam efficiency of all beams exceeds 90 % throughout the L band frequencies, with efficiency decreasing slowly as frequency increases. Subsequently, we developed a module to mitigate stray radiation effects, incorporating it into FAST's standard H\textsc{i} data reduction process, referred to as HiFAST. Our analysis shows that side lobe flux's influence, particularly for extended sources with significant surface density gradients, necessitates detailed evaluation. Corrections for the extended M33 galaxy can reach up to 20 %. Moreover, the pattern data presented here is vital for studying H\textsc{i} intensity maps at high redshift. The module, along with HiFAST and beam pattern data across 15 frequency bins, can be accessed at \href{https://hifast.readthedocs.io}{https://hifast.readthedocs.io}. The datasets of beam pattern presented in this paper are openly available at \href{https://doi.org/10.57760/sciencedb.j00113.00266}{https://doi.org/10.57760/sciencedb.j00113.00266}.

Key words: radio lines, galaxies-radio continuum, galaxies-methods, data analysis

中图分类号: (Observation and data reduction techniques; computer modeling and simulation)

95.75.-z

98.58.Ge (H I regions and 21-cm lines; diffuse, translucent, and high-velocity clouds) 98.70.Dk (Radio sources)

Qing-Ze Chen(陈箐泽), Jie Wang(王杰), Ying-Jie Jing(景英杰), Li-Gang Hou(侯立刚), Chen Xu(徐晨), Tian-Tian Liang(梁甜甜), Xu-Yang Gao(高旭阳), Jin-Lin Han(韩金林), Zi-Ming Liu(刘孜铭), Bin Liu(刘彬), Chuan-Peng Zhang(张传鹏), Heng-Qian Gan(甘恒谦), Ming Zhu(朱明), Yan Zhu(朱岩), and Peng Jiang(姜鹏). HiFAST: An H I data calibration and imaging pipeline for the FAST IV: The stray-radiation correction[J]. 中国物理B, 2026, 35(5): 59501-059501.

参考文献

[1] Jiang P, Yue Y, Gan H, Yao R, Li H, Pan G F, Sun J, Yu D, Liu H, Tang N Y, Qian L, Lu J, Su Y, Peng B, Zhang S X, Wang Q, Li Q and Li D 2019 Sci. China Phys. Mech. Astron. 62959502
[2] Gan H Q, Jiang P, Zhu K, Sun J H, Yao R and Yu D J 2020 Res. Astron. Astrophys. 20069
[3] Jiang P, Tang N Y, Hou L G, Liu M T, Krco M, Qian L, Sun J H, Ching T C, Liu B, Duan Y, Yue Y L, Gan H Q, Yao R, Li H, Pan G F, Yu D J, Liu H F, Li D, Peng B and Yan J 2020 Res. Astron. Astrophys. 20064
[4] Kalberla P M W, Mebold U and Reich W 1980 Astron. Astrophys. 82275
[5] Hartmann D, Kalberla P M W, Burton W B and Mebold U 1996 Astron. Astrophys. Suppl. Ser. 119115
[6] Kalberla P M W, Burton W B, Hartmann D, Arnal E M, Bajaja E, Morras R and Poppel W G L 2005 Astron. Astrophys. 440775
[7] Kalberla P M W, McClure-Griffiths N M, Pisano D J, Calabretta M R, Ford H A, Lockman F J, Staveley-Smith L, Kerp J, Winkel B, Murphy T and Newton-McGee K 2010 Astron. Astrophys. 521 A17
[8] Higgs L A, Landecker T L, Asgekar A, Davison O S, Rothwell T A and Yar-Uyaniker A 2005 Astron. J. 1292750
[9] Bajaja E, Arnal E M, Larrarte J J, Morras R, Poppel W G L and Kalberla P M W 2005 Astron. Astrophys. 440767
[10] Boothroyd A I, Blagrave K, Lockman F J, Martin P G, Gonçalves D P and Srikanth S 2011 Astron. Astrophys. 536 A48
[11] Winkel B, Kerp J, Floer L, Kalberla P M W, Ben Bekhti N, Keller R and Lenz D 2016 Astron. Astrophys. 585 A41
[12] Xu C K, Cheng C, Appleton P N, Duc P A, Gao Y, Tang N Y, Yun M, Dai Y S, Huang J S, Lisenfeld U and Renaud F 2022 Nature 610461
[13] Jing Y, Wang J, Xu C, Liu Z, Chen Q, Liang T, Xu J, Cao Y, Wang J, Hu H, Zhang C P, Guo Q, Gao L, Ai M, Gan H, Gao X, Han J, Hou L, Hou Z, Jiang P, Kong X, Li F, Liu Z, Shao L, Pan H, Pan J, Qian L, Sun J, Tang N, Yang Q, Zhang B, Zhang Z and Zhu M 2024 Sci. China Phys. Mech. Astron. 675
[14] Xu C, Wang J, Jing Y, Li F, Gan H, Liu Z, Liang T, Chen Q, Liu Z, Hou Z, Hu H, Hu H, Huang S, Jiang P, Zhang C P and Zhu Y 2025 Res. Astron. Astrophys. 25015011
[15] Liu Z, Wang J, Jing Y, Zhang Z Y, Xu C, Liang T, Chen Q, Tang N and Yang Q 2024 Res. Astron. Astrophys. 24085009
[16] Condon J J, Cotton W D, Greisen E W, Yin Q F, Perley R A, Taylor G B and Broderick J J 1998 Astron. J. 1151693
[17] Paturel G, Petit C, Prugniel P, Theureau G, Rousseau J, Brouty M, Dubois P and Cambresy L 2003 Astron. Astrophys. 41245

HiFAST: An H I data calibration and imaging pipeline for the FAST IV: The stray-radiation correction

HiFAST: An H I data calibration and imaging pipeline for the FAST IV: The stray-radiation correction

PDF (PC)

赞

可视化

摘要/Abstract

引用本文

使用本文

参考文献

相关文章 4

Metrics

本文评价

推荐阅读 0

[1]	Qiaoyu Guo(郭桥雨), Fei Xie(谢飞), Xuefei Feng(冯雪飞), Zhe Sun(孙喆), Changda Wang(王昌达), and Xuechen Jiao(焦学琛). GranuSAS: Software of rapid particle size distribution analysis from small angle scattering data[J]. 中国物理B, 2026, 35(2): 27802-027802.
[2]	Yongyi Yuan(袁泳怡), Jialun Liang(梁嘉伦), Chuang Tan(谭创), Xueying Yang(杨雪滢), Dongni Yang(杨东尼), and Jie Ma(马杰). Combination of density-clustering and supervised classification for event identification in single-molecule force spectroscopy data[J]. 中国物理B, 2023, 32(10): 108702-108702.
[3]	李华, 陈昱沆, 唐宾泽. A revised jump-diffusion and rotation-diffusion model[J]. 中国物理B, 2019, 28(5): 56105-056105.
[4]	陈天宇, 陈阳, 杨胡江, 肖井华, 胡岗. Reconstruction of dynamic structures of experimental setups based on measurable experimental data only[J]. 中国物理B, 2018, 27(3): 30503-030503.