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Forecasting supernova observations with the CSST:*** samples

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 164-177页

作者： Chengqi Liu Youhua Xu Xianmin Meng Xin Zhang Shi-Yu Li Yuming Fu Xiaofeng Wang Shufei Liu Zun Luo Guanghuan Wang Hu Zhan Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Beijing planetarium Beijing Academy of Science and TechnologyBeijing 100044China Leiden observatory Leiden UniversityNL-2300 RA LeidenThe Netherlands Kapteyn Astronomical Institute University of GroningenNL-9700 AV GroningenThe Netherlands Physics Department Tsinghua UniversityBeijing 100084China School of Astronomy and Space Science University of ChineseAcademy of SciencesBeijing 100049China

The China Space Station Telescope(CSST,also known as Xuntian)is a serviceable two-meter-aperture wide-field telescope operating in the same orbit as the China Space *** CSST plans to survey a sky area of 17,500 deg^(2)of the medium-to-high Galactic latitude to a depth of 25-26 AB mag in at least 6 photometric bands over 255-1,000 *** such a large sky area,slitless spectra will also be taken over the same wavelength range as the imaging *** though the CSST survey is not dedicated to time-domain studies,it would still detect a large number of transients,such as supernovae(SNe).In this paper,we simulate photometric SN observations based on a strawman survey plan using the Sncosmo *** its 10-year survey,the CSST is expected to observe about 5 million SNe of various *** quality cuts,we obtain a“gold”sample that comprises roughly 7,400 SNe Ia,2,200 SNe Ibc,and 6,500 SNeⅡcandidates with correctly classified percentages reaching 91%,63%,and 93%(formally defined as classification precision),*** same survey can also trigger alerts for the detection of about 15,500 SNe Ia(precision 61%)and 2,100 SNeⅡ(precision 49%)candidates at least two days before the light ***,the near-ultraviolet observations of the CSST will be able to catch hundreds of shock-cooling events serendipitously every *** results demonstrate that the CSST can make a potentially significant contribution to SN studies.

关键词： space-based ultraviolet optical and infrared telescopes supernovae data analysis

Revision of the photometric parameters of BS Cassiopeiae

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Research in Astronomy and Astrophysics 2010年第6期10卷 569-576页

作者： Jia-Jia He Sheng-Bang Qian Miloslav Zejda Zdenek Mikulasek National Astronomical Observatories / Yunnan observatory Chinese Academy of Sciences Kunming 650011 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Key Laboratory for the Structure and Evolution of Celestial Objects National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Institute of Theoretical Physics and Astrophysics Masaryk University Kotlarska 2 611 37 Brno Czech Republic observatory and planetarium of J. Palisa VSB- Technical University Ostrava Czech Republic

Seven charge-coupled device （CCD） photometric times of light minimum of the overcontact binary BS Cas which were obtained from 2007 August to November and one CCD light curve in the R band which was observed on 2007 September 24 and October 15, are presented. It is found that the light curve ofBS Cas has characteristics like a typical EW-type light variation. The light curve obtained by us is symmetric and shows total eclipses, which is very useful for determining photometric parameters with high precision. Photometric solutions were derived by using the 2003 version of the Wilson-Devinney code. It shows that BS Cas is a W-subtype overcontact binary （f = 27.5% ± 0.4%） with a mass ratio of q = 2.7188± 0.0040. The temperature difference between the two components is 190 K. Analysis of the 042 curve suggests that the period of AE Phe shows a long-term continuous decrease at a rate of dP/dt = - 2.45 × 10^-7 d yr^- 1 The long-time period decrease can be explained by mass transfer from the primary to the secondary.

关键词： stars binaries close -- stars binaries eclipsing -- stars individual BS Cas

Deriving the coronal hole electron temperature: electron density dependent ionization / recombination considerations

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Research in Astronomy and Astrophysics 2010年第1期10卷 91-95页

作者： John Gerard Doyle Steven Chapman Paul Bryans David Pérez-Suárez Avninda Singh Hugh Summers Daniel Wolf Savin armagh observatory College HillArmagh BT61 9DGN.Ireland Centre for Astrophysics University of Central LancashirePrestonUK Space Science Division Naval Research LaboratoryWashingtonDC 20375USA George Mason University 4400 University DriveFairfaxVA 22020USA Department of Physics & Electronics Deen Dayal Upadhyaya CollegeUniversity of DelhiIndia Department of Physics University of Strathclyde107 RottenrowGlasgowG4 0NGScotland Columbia Astrophysics Laboratory 550 W 120th StNew YorkNY 10027USA

Comparison of appropriate theoretically derived line ratios with observational data can yield estimates of a plasma＇s physical parameters, such as electron density or temperature. The usual practice in the calculation of the line ratio is the assumption of excitation by electrons/protons followed by radiative decay. Furthermore, it is normal to use the so-called coronal approximation, i.e. one only considers ionization and recombination to and from the ground-state. A more accurate treatment is to include ionization/recombination to and from metastable levels. Here, we apply this to two lines from adjacent ionization stages, Mg IX 368A and Mg × 625A, which has been shown to be a very useful temperature diagnostic. At densities typical of coronal hole conditions, the difference between the electron temperature derived assuming the zero density limit compared with the electron density dependent ionization/recombination is small. This, however, is not the case for flares where the electron density is orders of magnitude larger. The derived temperature for the coronal hole at solar maximum is around 1.04MK compared to just below 0.82MK at solar minimum.

关键词： atomic processes - line formation - Sun activity

Optical and X-Ray Observations of MAXI J1820+070 During the Early Outburst Phase in 2018:Zooming in the Low Frequency QPOs

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Research in Astronomy and Astrophysics 2022年第4期22卷 106-113页

作者： Dong-Ming Mao Wen-Fei Yu Ju-Jia Zhang Zhen Yan Stefano Rapisarda Xiao-Feng Wang Jin-Ming Bai Shanghai Astronomical observatory Chinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Key Laboratory for the Structure and Evolution of Celestial Objects CASKunming 650216China Physics Department Tsinghua UniversityBeijing 100084China Beijing planetarium Beijing Academy of Sciences and TechnologyBeijing 100044China

We report a further investigation of the optical low frequency quasi periodic oscillations(LF QPOs)detected in the black hole transient MAXI J1820+070 in the 2018 observations with the YFOSC mounted on Lijiang 2.4 m telescope(LJT).In addition,we make use of the Insight-HXMT/HE observations to measure the properties of the quasi-simultaneous X-ray LF QPOs of MAXI J1820+070 on the same *** compared the centroid frequency,the full width at half maximum(FWHM)and the fractional rms of the LF QPOs in both wavelength *** found that the centroid frequency of the optical QPO is at a frequency of 51.58 m Hz,which is consistent with that of the X-ray LF QPO detected on the same day within 1 m *** also found that the FWHM of the optical LF QPO is significantly smaller than that of the X-ray LF QPO,indicating that the optical QPO has a higher *** quasi-simultaneous optical and the X-ray LF QPO at a centroid frequency of about 52 m Hz suggests that the actual mechanisms of these LF QPOs as the Lense-Thirring precession should work in the vicinity of a radius of about 80-117 gravitational radii(R_(g)=GM/c^(2),M is the mass of the black hole)from the black hole if the QPO frequency is related to a proxy of the orbital frequency in the accretion fiow as the Lense-Thirring precession model ***,the apparent higher coherence of the optical QPO favors that it is a more original signal as compared with the X-ray QPO.

关键词： X-ray stars Low mass binary stars X-ray transient sources

The Potentially Dangerous Asteroid （99942） Apophis

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Journal of Earth Science and Engineering 2014年第6期4卷 385-388页

作者： Ireneusz Wlodarczyk Chorzow Astronomical observatory Chorzow Planetarium Chorzow PL41501 Poland Polish Astronomical Amateur Society Departement in Rozdrazew Rozdrazew PL63708 Poland

This paper computed the newest impact solutions of the potentially dangerous asteroid （99942） Apophis based on 4,138 optical observations from March 15.10789 UTC （Universal Time Coordinated）, 2004 to February 28.089569 UTC, 2014 and 20 radar observations from January 27, 2005 through March 15, 2013, as of June 20, 2014. Using the freely available the OrbFit software Package, this paper followed its orbit forward in the searching for close approaches with the Earth and possible impacts up to year 2116. With the different A2 non-gravitational parameter in the motion of the asteroid （99942） Apophis, this paper computed possible impact solutions using the JPL DE405 （Jet Propulsion Laboratory Development Ephemeris） and 25 additional massive perturbed asteroids. Additionally, this paper used weighing and selection methods adopted in the OrbFit software as prepared by the NEODyS （Near Earth Objects--Dynamical Side） Team. Moreover, this paper used method of computing the orbit of Apophis taking into account star catalog debiasing and an error model with assumed astrometric errors RMS （root mean square）, deduced from the observational material of the given observatories. JPL＇s Sentry and NEODyS＇s CLOMMON2, two automatic monitoring systems routinely scanning for possible impacts in the next hundred years. Only for several dangerous asteroids presented results are computed with the non-gravitational parameters. This paper detected possible impacts of the asteroid （99942） Apophis only with the non-gravitational parameter, A2 〉 0. It was appeared that impacts in 2068, 2087, 2105 and in 2111 were possible only when Apophis rotated in prograde direction.

关键词： Astrometry minor planets individual asteroids Apophis (99942).

The Halo Concentration and Mass Relation Traced by Satellite Galaxies

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Research in Astronomy and Astrophysics 2022年第12期22卷 292-298页

作者： Qing Gu Qi Guo Tianchi Zhang Wenting Wang Quan Guo Liang Gao Key Laboratory for Computational Astrophysics National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Beijing planetarium Beijing Academy of Science and TechnologyBeijing 100044China Department of Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai 200240China Shanghai Astronomical observatory Chinese Academy of SciencesShanghai 200030China Institute of Computational Cosmology Department of PhysicsUniversity of DurhamScience LaboratoriesSouth RoadDurham DH13LEUK

We study the relation between halo concentration and mass(c-M relation) using galaxy catalogs of the Seventh and Eighth Data Releases of the Sloan Digital Sky Survey(SDSS DR7 and DR8). Assuming that the satellite galaxies follow the distribution of dark matter, we derive the halo concentration by fitting the satellite radial profile with a Nararro Frank and White(NFW) format. The derived c-M relation covers a wide halo mass range from10^(11.6)to 10^(14.1)M_(⊙). We confirm the anti-correlation between the halo mass and concentration as predicted in cosmological simulations. Our results are in good agreement with those derived using galaxy dynamics and gravitational lensing for halos of 10^(11.6)– 10^(12.9)M_(⊙), while they are slightly lower for halos of 10^(12.9)– 10^(14.1)M_(⊙).This is because blue satellite galaxies are less concentrated, especially in the inner regions. Instead of using all satellite galaxies, red satellites could be better tracers of the underlying dark matter distribution in galaxy groups.

关键词： galaxies:halos galaxies:evolution galaxies:abundances

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丹尼克·寇帕尔双星遗物

国外科技新书评介 2006年第7期 10-11页

作者： H．德施尔（编） M．泽达（编）康连生 Remeis observatory Bamberg Germany N. Copernicus observatory and planetarium Brno Czech Republik（ Eds. ）中国科学院国家天文台高级工程师

丹尼克·寇帕尔教授是20世纪世界最著名天文学家之一，他从事致密双星系统科学研究近60年。为祝福丹尼克·寇帕尔教授90大寿，2004年3月31日至4月3日，在他的家乡捷克斯洛伐克共和国波希米亚小镇举行了“丹尼克·寇帕尔双星遗物”国际... 详细信息

丹尼克·寇帕尔教授是20世纪世界最著名天文学家之一，他从事致密双星系统科学研究近60年。为祝福丹尼克·寇帕尔教授90大寿，2004年3月31日至4月3日，在他的家乡捷克斯洛伐克共和国波希米亚小镇举行了“丹尼克·寇帕尔双星遗物”国际会议。

关键词：双星系统遗物捷克斯洛伐克天文学家 20世纪科学研究国际会议共和国教授

Forecast of cosmological constraints with type Ia supernovae from the Chinese Space Station Telescope

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Science China(Physics,Mechanics & Astronomy) 2023年第2期66卷 131-139页

作者： Shi-Yu Li Yun-Long Li Tianmeng Zhang Jozsef Vink Eniko Regos Xiaofeng Wang Gaobo Xi Hu Zhan Beijing planetarium Beijing Academyof Scienceand TechnologyBeijing 100044China National Space Science Center Chinese Academyof SciencesBeijing 100190China National Space ScienceData Centerof China Beijing 101407China Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 1oo10lChina School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China Konkoly observatory Konkoly Institute of AstronomyKonkoly Thege M.ut 15-17Budapest 1121Hungary ELTE Eotvos Lorand University Institute of PhysicsPazmany Peter setany I/ABudapest 1117Hungary Institute of Physics Universityof SzegedDom ter9Szeged 6720Hungary Physics Department and Tsinghua Center for Astrophysics(THCA) Tsinghua UniversityBeijing 100084China Kavli Institute forAstronomy and Astrophysics Peking UniversityBeijingio0871China

The 2-m aperture Chinese Space Station Telescope(CSST),which observes at wavelengths ranging from 255 to 1000 nm,is expected to start science operations in *** ultra-deep field observation program covering approximately 10 deg2is proposed with supernovae(SNe) and other transients as one of its primary science *** paper presents the simulated detection results of type Ⅰa supernovae(SNe Ⅰa) and explores the impact of new datasets on the determinations of cosmological *** simulated observations are conducted with an exposure time of 150 s and cadences of 10,20,and 30 *** survey mode covering a total of 80 observations but with a random cadence in the range of 4 to 14 d is also *** simulation results indicate that the CSST can detect up to ~1800 SNe la at z <*** simulated SNe la are then used to constrain the cosmological *** constraint on can be improved by 37.5% using the 10-d cadence sample in comparison with the Pantheon sample.A deeper measurement simulation with a 300 s exposure time together with the Pantheon sample improves the current constraints on Ωmby 58.3% and ω by 47.7%.Taking future lager sets of nearby SN Ⅰa sample form ground-based surveys(i.e.,N~3400) into consideration,the constraints on ω can be improved by 59.1%.The CSST ultra-deep field observation program is expected to discover large amounts of SNe la over a broad redshift span and enhance our understanding of the nature of dark energy.

关键词： supernovae survey Station

An Overview of FAST Real-time Fast Radio Burst Searching System

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天文和天体物理学研究:英文版 2023年第9期23卷 251-263页

作者： X.X.Zhang R.Duan V.Gajjar H.Y.Zhang P.Wang C.H.Niu D.Werthimer J.Cobb S.Y.Li X.Pei Y.Zhu D.Li National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Department of Astronomy University of California BerkeleyBerkeleyCA94720.USA Hebei Key Laboratory of Radio Astronomy Technology Shijiazhuang 050081China Space Sciences Laboratory University of California BerkeleyBerkeleyCA 94720USA Beijing planetarium Beijing Academy of Science and TechnologyBeijing 100044China Xinjiang Astronomical observatory Chinese Academy of SciencesUrumqi 830011China NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa

In this paper,we report a real-time Fast Radio Burst(FRB)searching system that has been successfully implemented with the 19 beam receiver of the Five-hundred-meter Aperture Spherical radio Telescope(FAST).The relatively small field of view of FAST makes the search for new FRBs challenging,but its high sensitivity significantly improves the accuracy of FRB localization and enables the detection of high-precision neutral hydrogen absorption lines generated by *** goal is to develop an FRB searching system capable of realtime detection of FRBs that allows high-time resolution spectro-temporal studies among the repeated bursts,as well as detailed investigations of these bursts and exploration of FRB progenitor *** data from each beam of the 19-beam receiver are fed into a high-performance computing node server,which performs real-time searches for pulses with a wide dispersion measure(DM)range of 20–10,000 pc cm^(-3) with step efficiency of 25%in real ***,the head node server aggregates all the candidate signals from each beam within a given time,determining their authenticity based on various criteria,including arrival time,pulse width,signal-to-noise ratio and coincidence patterns among the 19 *** the 1.05–1.45 GHz operating bandwidth of the FAST 19beam receiver,the system achieves a frequency resolution of 122.07 kHz and a time resolution of 270.336μ***,our team detected a series of bursts with a DM of 566 on 2019 August 30 confirming them as *** FRB searching system enables the 19-beam receiver of FAST to detect repeated/one-off pulses/bursts in real time.

关键词： Astronomical Instrumentation-Methods and Techniques-instrumentation spectrographs-methods miscellaneous