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The FRB-searching Pipeline of the Tianlai Cylinder Pathfinder Array

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Research in astronomy and astrophysics 2024年第8期24卷 113-132页

作者： Zijie Yu Furen Deng Shijie Sun Chenhui Niu Jixia Li Fengquan Wu Wei-Yang Wang Yougang Wang Shifan Zuo Lin Shu Jie Hao xiaohui Liu Reza Ansari Ue-Li Pen Albert Stebbins Peter Timbie Xuelei Chen National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China university of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio astronomy and Technology Chinese Academy of ScienceBeijing 100101China institute of astrophysics Central China Normal UniversityWuhan 430079China institute of Automation Chinese Academy of SciencesBeijing 100190China Guangdong institute of Artificial Intelligence and Advanced Computing Guangzhou 510535China UniversitéParis-Saclay CNRS/IN2P3IJCLab91405 OrsayFrance institute of astronomy and astrophysics Academia SinicaRoosevelt RoadTaipei 10617TaiwanChina Canadian institute for Theoretical astrophysics University of Toronto60 Saint George StreetTorontoON M5S 3H8Canada Department of Physics University of Wisconsin-MadisonMadisonWI 53706USA Fermi National Accelerator Laboratory P.O.Box 500Batavia IL 60510-5011USA Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Center of High Energy Physics Peking UniversityBeijing 100871China

This paper presents the design,calibration,and survey strategy of the Fast Radio Burst(FRB)digital backend and its real-time data processing pipeline employed in the Tianlai Cylinder Pathfinder *** array,consisting of three parallel cylindrical reflectors and equipped with 96 dual-polarization feeds,is a radio interferometer array designed for conducting drift scans of the northern celestial *** FRB digital backend enables the formation of 96 digital beams,effectively covering an area of approximately 40 square degrees with the 3 dB *** pipeline demonstrates the capability to conduct an automatic search of FRBs,detecting at quasi-realtime and classifying FRB candidates *** current FRB searching pipeline has an overall recall rate of88%.During the commissioning phase,we successfully detected signals emitted by four well-known pulsars:PSR B0329+54,B2021+51,B0823+26,and B2020+*** report the first discovery of an FRB by our array,designated as FRB *** also investigate the optimal arrangement for the digitally formed beams to achieve maximum detection rate by numerical simulation.

关键词： instrumentation interferometers-methods data analysis-(stars )pulsars general-telescopes

On the Energy Budget of Starquake-induced Repeating Fast Radio Bursts

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Research in astronomy and astrophysics 2024年第10期24卷 180-188页

作者： Wei-Yang Wang Chen Zhang Enping Zhou xiaohui Liu Jiarui Niu Zixuan Zhou He Gao Jifeng Liu Renxin Xu Bing Zhang School of astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China The HKUST Jockey Club institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina School of Physics Huazhong University of Science and TechnologyWuhan 430074China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Mathematics and Physics University of Science and TechnologyBeijing 100083China Department of astronomy Beijing Normal UniversityBeijing 100875China New Cornerstone Science Laboratory National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China institute for Frontiers in astronomy and astrophysics Beijing Normal UniversityBeijing 102206China Nevada Center for astrophysics University of NevadaLas VegasNV 89154USA Department of Physics and astronomy University of NevadaLas VegasNV 89154USA

With a growing sample of fast radio bursts(FRBs),we investigate the energy budget of different power sources within the framework of magnetar starquake triggering *** a starquake,the energy can be released in any form through strain,magnetic,rotational,and gravitational *** strain energy can be converted from three other kinds of energy during *** following findings are revealed:(1)The crust can store free magnetic energy of~10^(46)erg by existing toroidal fields,sustaining 10^(6)bursts with frequent starquakes occurring due to crustal instability.(2)The strain energy develops as a rigid object spins down,which can be released during a global starquake accompanied by a ***,it takes a long time to accumulate enough strain energy via spindown.(3)The rotational energy of a magnetar with P■0.1 s can match the energy and luminosity budget of FRBs.(4)The budget of the total gravitational energy is high,but the mechanism and efficiency of converting this energy to radiation deserve further exploration.

关键词： stars:magnetars stars:neutron radiation mechanisms:non-thermal

Nearby source interpretation of differences among light and medium composition spectra in cosmic rays

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Frontiers of physics 2021年第2期16卷 195-200页

作者： Qiang Yuan Bing-Qiang Qiao Yi-Qing Guo Yi-Zhong fan Xiao-Jun Bi Key Laboratory of Dark Matter and Space astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of astronomy and Space Science University of Science and Technology of ChinaHefei 230026China Center for High Energy Physics Peking UniversityBeijing 100871China Key Laboratory of Particle astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China university of Chinese Academy of Sciences Beijing 100049China

Recently the AMS-02 reported the precise measurements of the energy spectra of medium-mass compositions(Neon,Magnesium,Silicon)of primary cosmic rays,which reveal different properties from those of light compositions(Helium,Carbon,Oxygen).Here we propose a nearby source scenario,together with the background source contribution,to explain the newly measured spectra of cosmic ray Ne,Mg,Si,and particularly their differences from that of He,C,*** differences at high energies can be naturally accounted for by the element abundance of the nearby ***,the abundance ratio of the nearby source to the background of the Ne,Mg,Si elements is lower by a factor of~1.7 than that of the He,C,O *** a diference could be due to the abundance difference of the stellar evolution of the progenitor star or the acceleration process/environment,of the nearby *** scenario can simultaneously explain the high-energy spectral softening features of cos-mic ray spectra revealed recently by CREAM/NUCLEON/DAMPE,as well as the energy-dependent behaviors of the large scale *** is predicted that the dipole anisotropy amplitudes below PeV energies of the Ne,Mg,Si group are smaller than that of the He,C,O group,which can be tested with future measurements.

关键词： cosmic rays spectra and anisotropies

South Galactic Cap u-band Sky Survey(SCUSS):Project Overview

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Research in astronomy and astrophysics 2016年第4期16卷 133-144页

作者： Xu Zhou Xiao-Hui fan Zhou fan Bo-Liang He Lin-Hua Jiang Zhao-Ji Jiang Yi-Peng Jing Michael Lesser Jun Ma Jun-Dan Nie Shi-Yin Shen Jia-Li Wang Zhen-Yu Wu Tian-Meng Zhang Zhi-Min Zhou Hu Zou Key Laboratory of Optical astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012China Steward Observatory University of ArizonaTucsonAZ 85721USA Center for astronomy and astrophysics Department of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China kavli institute for astronomy and astrophysics Peking UniversityBeijing 100871China

The South Galactic Cap u-band Sky Survey （SCUSS） was established in 2009 in order to provide a photometric input catalog for target selection of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope （LAMOST） project. SCUSS is an international cooperative project between National Astronomical Observatories, Chinese Academy of Sciences, and Steward Observatory at the university of Arizona, using the 90 inch （2.3 m） Bok telescope on Kitt Peak. The telescope is equipped with a prime focus camera that is composed of a mosaic of four 4096 × 4096 CCDs and has a field of view of about 1 deg2. From 2009 to 2013, SCUSS performed a sky survey of an approximately 5000 deg2 field of the South Galactic Cap in u band, including the Galactic anticenter area and the SDSS-IV extended imaging area. The limiting magnitude of SCUSS is deeper than 23 mag （at a signal-to-noise ratio of 5）. In this paper, we briefly describe the goals of this project, method of observations and data reduction, and we also introduce current and potential scientific activities related to the SCUSS project.

关键词： observation: sky survey -- techniques: data reduction -- objects: stars and galaxies

A comparison between repeating bursts of FRB 121102 and giant pulses from Crab pulsar and its applications

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Frontiers of Physics 2021年第2期16卷 203-209页

作者： Fen Lyu Yan-Zhi Meng Zhen-fan Tang Ye Li Jun-Jie Wei Jin-Jun Geng Lin Lin Can-Min Deng Xue-Feng Wu Purple Mountain Observatory Chinese Academy of Sciences university of Chinese Academy of Sciences School of astronomy and Space Science Nanjing University kavli institute for astronomy and astrophysics Peking University institute of astronomy and astrophysics University of Tübingen Department of astronomy Beijing Normal University Department of astronomy University of Science and Technology of China School of astronomy and Space Sciences University of Science and Technology of China

There are some similarities between bursts of repeating fast radio bursts（FRBs） and giant pulses（GPs）of pulsars. To explore possible relations between them, we study the cumulative energy distributions of these two phenomena using the observations of repeating FRB 121102 and the GPs of Crab pulsar. We find that the power-law slope of GPs（with fluence ≥130 Jy·ms） is 2.85±0.10. The energy distribution of FRB 121102 can be well fitted by a smooth broken power-law function. For the bursts of FRB121102 above the break energy(1.22 ×1037erg), the best-fitting slope is 2.90-0.44+0.55, similar to the index of GPs at the same observing frequency（～1.4 GHz）. We further discuss the physical origin of the repeating FRB 121102 in the framework of the super GPs model. And we find that the super GPs model involving a millisecond pulsar is workable and favored for explaining FRB 121102 despite that the magnetar burst model is more popular.

关键词： pulsars radio sources general-methods: statistical

A comparison between repeating bursts of FRB 121102 an giant pulses from Crab pulsar and its applications

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Frontiers of physics 2021年第2期16卷 201-207页

作者： Fen Lyu Yan-Zhi Meng Zhen-fan Tang Ye Li Jun-Jie Wei Jin-Jun Geng Lin Lin Can-Min Deng Xue-Feng Wu Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China university of Chinese Academy of Sciences Beijing 100049China School of astronomy and Space Science Nanjing UniversityNanjing 210023China kavli institute for astronomy and astrophysics Peking UniversityBeijing 100871China institute of astronomy and astrophysics University of TubingenAuf der Morgenstelle 10D-72076TubingenGermany Department of astronomy Beijing Normal UniversityBeijing 100875China Department of astronomy University of Science and Technology of ChinaHefei 230026China School of astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

There are some similarities between bursts of repeating fast radio bursts(FRBs)and giant pulses(GPs)of *** explore possible relations between them,we study the cumulative energy distributions of these two phenomena using the observations of repeating FRB 121102 and the GPs of Crab *** find that the power-law slope of GPs(with fuence≥130 ***)is 2.85±*** energy distribution of FRB 121102 can be well fitted by a smooth broken power-law *** the bursts of FRB 121102 above the break energy(1.22×10^(37)erg),the best-ftting slope is 2.90^(+0.55)_(-0344),similar to the index of GPs at the same observing frequency(~1.4 GHz).We further discuss the physical origin of the repeating FRB 121102 in the framework of the super GPs *** we find that the super GPs model involving a millisecond pulsar is workable and favored for explaining FRB 121102 despite that the magnetar burst model is more popular.

关键词： pulsars radio sources general-methods:statistical

The LEGUE high latitude bright survey design for the LAMOST pilot survey

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Research in astronomy and astrophysics 2012年第7期12卷 792-804页

作者： Yue-Yang Zhang Jeffrey L. Carlin fan Yang Chao Liu Li-Cai Deng Heidi Jo Newberg Hao-Tong Zhang Sebastien Lepine Yan Xu Shuang Gao Norbert Chfi' stlieb Zhan-Wen Han Jin-Liang Hou Hsu-Tai Lee Xiao-Wei Liu Kai-Ke Pan Hong-Chi Wang Key Lab for Optical astronomy National Astronomical Observatories Chinese Academy ofSciences Beijing 100012 China Graduate university of Chinese Academy of Sciences Beijing 100049 China Department of astrophysics Division of Physical Sciences American Museum of NaturalHistory Central Park West at 79th Street New York NY 10024 USA Department of Physics Applied Physics and Astronomy Rensselaer Polytechnic Institute 1108th Street Troy NY 12180 USA carlij@rpi.edu university of Heidelberg Landesstemwarte K6nigstuhl 12 D-69117 Heidelberg Germany Yunnan Astronomical Observatory Chinese Academy of Sciences Kunming 65()011 China Shanghai Astronomical Observatory Chinese Academy of Sciences Shangthai 200030 China institute of astronomy and astrophysics Academia Sinica EO. Box 23-141 Taipei 106 China Department of astronomy & kavli institute of astronomy and astrophysics Peking UniversityBeijing 100871 China Apache Point Observatory PO Box 59 Sunspot NM 88349 USA Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

We describe the footprint and input catalog for bright nights in the LAMOST Pilot Survey, which began in October 2011. Targets are selected from two stripes in the north and south Galactic Cap regions, centered at δ = 29°, with 10° width in declination, covering right ascensions of 135° to 290° and -30° to 30° re- spectively. We selected spectroscopic targets from a combination of the SDSS and 2MASS point source catalogs. The catalog of stars defining the field centers （as re- quired by the Shack-Hartmann wavefront sensor at the center of the LAMOST field） consists of all V 〈 8m stars from the Hipparcos catalog. We employ a statistical selection algorithm that assigns priorities to targets based on their positions in mul- tidimensional color/magnitude space. This scheme overemphasizes rare objects and de-emphasizes more populated regions of magnitude and color phase space, while en- suring a smooth, well-understood selection function. A demonstration of plate design is presented based on the Shack-Hartmann star catalog and an input catalog that was generated by our target selection routines.

关键词： surveys: LAMOST -- techniques: spectroscopic -- Galaxy: stellar con-tent

The LEGUE input catalog for dark night observing in the LAMOST pilot survey

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Research in astronomy and astrophysics 2012年第7期12卷 781-791页

作者： fan Yang Jeffrey L. Carlin Chao Liu Yue-Yang Zhang Shuang Gao Yan Xu Li-Cai Deng Heidi Jo Newberg Sebastien Lepine Jin-Liang Hou Xiao-Wei Liu Norbert Christlieb Hao-Tong Zhang Hsu-Tai Lee Kai-Ke Pan Zhan-Wen Han Hong-Chi Wang Key Lab for Optical astronomy National Astronomical Observatories Chinese Academy ofSciences Beijing 100012 China fyang@*** Graduate university of Chinese Academy of Sciences Beijing 100049 China Department of Physics Applied Physics-and Astronomy Rensselaer Polytechnic Institute 1108th Street Troy NY 12180 USA American Museum of Natural History Central Park West at 79th Street New York NY 10024USA Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Department of astronomy & kavli institute of astronomy and astrophysics Peking UniversityBe~iing 100871 China university of Heidelberg Landessternwarte K6nigstuhl 12 D-69117 Heidelberg Germany institute of astronomy and astrophysics Academia Sinica EO. Box 23-14 I Taipei 106 China Apache Point Observatory EO. Box 59 Sunspot NM 88349 USA Yunnan Astronomical Observatory Chinese Academy of Sciences Kunming 650011 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 2100-08 China

We outline the design of the dark nights portion of the LAMOST Pilot Survey, which began observations in 2011 October. In particular, we focus on Milky Way stellar candidates that are targeted for the LEGUE （LAMOST Experiment for Galactic Understanding and Exploration） survey. We discuss the regions of sky in which spectroscopic candidates were selected, and the motivations for selecting each of these sky areas. Some limitations due to the unique design of the telescope are discussed, including the requirement that a bright （V 〈 8） star be placed at the center of each plate for wavefront sensing and active optics corrections. The target selection categories and scientific goals motivating them are briefly discussed, followed by a detailed overview of how these selection functions were implemented. We illustrate the difference between the overall input catalog - Sloan Digital Sky Survey （SDSS） photometry - and the final targets selected for LAMOST observations.

关键词： surveys: LAMOST -- Galaxy: halo -- techniques: spectroscopic

The site conditions of the Guo Shou Jing Telescope

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Research in astronomy and astrophysics 2012年第7期12卷 772-780页

作者： Song Yao Chao Liu Hao-Tong Zhang Li-Cai Deng Heidi Jo Newberg Yue-Yang Zhang Jing Li Nian Liu Xu Zhou Jeffrey L. Carlin Li Chen Norbert Christlieb Shuang Gao Zhan-Wen Han Jin-Liang Hou Hsu-Tai Lee Xiao-Wei Liu Kai-Ke Pan Hong-Chi Wang Yan Xu fan Yang Key Lab of Optical astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate university of Chinese Academy of Sciences Beijing 100049 China Department of Physics Applied Physics and Astronomy Rensselaer Polytechnic Institute 1108th Street Troy NY 12180 USA : School of Physics and Electronic Information China West Normal University Nanchong 637000 China Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Center for astronomy University of Heidelberg Landesstemwarte K6nigstuhl 12 D-69117Heidelberg Germany Yunnan Astronomical Observatory Chinese Academy of Sciences Kunming 650011 China institute of astronomy and astrophysics Academia Sinica P.O. Box 23-141 Taipei i06 China Department of astronomy & kavli institute of astronomy and astrophysics Peking UniversityBeijing 100871 China Apache Point Observatory PO Box 59 Sunspot NM 88349 USA Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

The weather at the Xinglong Observing Station, where the Guo Shou Jing Telescope （GSJT） is located, is strongly affected by the monsoon climate in north- east china. The LAMOST survey strategy is constrained by these weather patterns. We present statistics on observing hours from 2004 to 2007, and the sky brightness, seeing, and sky transparency from 1995 to 2011 at the site. We investigate effects of the site conditions on the survey plan. Operable hours each month show a strong cor- relation with season： on average there are eight operable hours per night available in December, but only one-two hours in July and August. The seeing and the sky trans- parency also vary with season. Although the seeing is worse in windy winters, and the atmospheric extinction is worse in the spring and summer, the site is adequate for the proposed scientific program of the LAMOST survey. With a Monte Carlo simulation using historical data on the site condition, we find that the available observation hours constrain the survey footprint from 22h to 16h in right ascension; the sky brightness allows LAMOST to obtain a limiting magnitude of V = 19.5 mag with S/N= 10.

关键词： telescopes - site testing - surveys