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Chinese Journal of Astronomy and Astrophysics 2006年第2期6卷 165-174页

作者： Fan Zhang xue-bing wu Department of Astronomy Peking University Beijing 100871

Simultaneous multi-wavelength observations have revealed complex variability in AGNs. To explain the variability we considered a theoretical model consisting of an inner hot comptonizing corona and an outer thin accretion disk, with interactions between the two components in the form of comptonization and reprocessing. We found that the variability of AGNs is strongly affected by the parameters of the model, namely, the truncated disk radius rmin, the corona radius rs, the temperature KTe and the optical depth TO of the corona. We applied this model to the two best observed Seyfert 1 galaxies, NGC 5548 and NGC 4051. Our model can reproduce satisfactory the observed SEDs. Our fits indicate that NGC 5548 may have experienced dramatic changes in physical parameters between 1989-1990 and 1998, and that NGC 4051 has a much larger truncated disk radius （700 Schwarzschild radii） than NGC 5548 （several tens of Schwarzschild radii）. Since we adopted a more refined treatment of the comptonization process rather than simply assuming a cut-off power law, our results should be more reasonable than the previous ones.

关键词： accretion - accretion disks - galaxies: active - galaxies: individual (NGC 5548 NGC 4051) - galaxies: Seyfert - X-rays: galaxies

Radio Identifications of Markarian Galaxies and the Correlation between Radio and Far-Infrared Properties

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Chinese Journal of Astronomy and Astrophysics 2005年第5期5卷 448-456页

作者： Shao-Guang Luo xue-bing wu Department of Astronomy Peking University Beijing 100871 Shenzhen Graduate School Peking University Shenz-hen 518055

By checking DSS optical images and NVSS radio images, 782 Markarian galaxies were identified to be NVSS radio sources. A comparison of the radio luminosity at 1.4GHz and the far-infrared （FIR） luminosity for 468 “normal” galaxies shows a tight correlation. Most of the Seyfert galaxies and quasars follow the radio-FIR relation deduced from the “normal” galaxy sample, but with a somewhat larger scatter. A total 167 Markarian galaxies, comprising 100 “normal” galaxies, 66 Seyfert galaxies and one quasar, have either excess radio emission or much lower FIR spectral index α（25 μm, 60 μm）. These galaxies may be classified as “AGN-powered”. For “normal” galaxies, the average q value （defined as the log ratio between FIR and radio luminosities） is 2.3. There seems a trend for q to slightly decrease with increasing radio luminosity. This may imply that the ongoing active star formation in galaxies with higher radio luminosities is more efficient in heating the cosmic-ray electrons.

关键词： galaxies: active - galaxies: Seyfert - galaxies: starburst - radio continuum: galaxies - infrared: galaxies

Estimating Black Hole Masses of AGNs using Ultraviolet Emission Line Properties

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Chinese Journal of Astronomy and Astrophysics 2006年第4期6卷 396-410页

作者： Min-Zhi Kong xue-bing wu Ran Wang Jin-Lin Han National Astronomical Observatories Chinese Academy of Sciences Beiiing 1000121 Department of Astronomy Peking University Beijing 100871

Based on measured broad line region sizes in the reverberation-mapping AGN sample, two new empirical relations are introduced to estimate the central black hole masses of radio-loud high-redshift （z 〉 0.5） AGNs. First, using the archival IUE/HST spectroscopy data at UV band for the reverberation-mapping objects, we obtained two new empirical relations between the BLR size and Mg Ⅱ/C Ⅳ emission line luminosity. Secondly, using the newly determined black hole masses of the reverberation-mapping sample as calibration, we found two new relationships for determining the black hole mass with the full width at half maximum and the luminosity of Mg Ⅱ/C Ⅳ line. We then apply the relations to estimate the black hole masses of the AGNs in the Large Bright Quasar Survey and a sample of radio-loud quasars. For the objects with small radio-loudness, the black hole mass estimated using the RBLR-LMg Ⅱ/C Ⅳ relation is consistent with that from the RBLR-L3000 A/1350 A relation. For radio-loud AGNs, however, the mass estimated from the RBLR-LMg Ⅱ/C Ⅳ relation is systematically lower than that from the continuum luminosity L3000 A/13S0 A Because jets could have significant contributions to the UV/optical continuum luminosity of radio-loud AGNs, we emphasize once again that for radio-loud AGNs, the emission line luminosity may be a better tracer of the ionizing luminosity than the continuum luminosity, so that the relations between the BLR size and UV emission line luminosities should be used to estimate the black hole masses of high redshift radio-loud AGNs.

关键词： galaxies: nucleus -- galaxies: high-redshift-- quasars: emission lines -- ultraviolet: galaxies

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发现最古老的超大质量黑洞

科学通报 2022年第22期67卷 2605-2609页

作者：吴学兵北京大学物理学院天文学系北京100871 北京大学科维理天文与天体物理研究所北京100871

美国《科学新闻》(Science News)杂志网站在2021年12月20日的报道中,梳理了2021年度令人惊奇的六大科学纪录,其中天文学家发现的迄今最古老的巨大黑洞(即红移为7.642的类星体J0313-1806中心质量为16亿倍太阳质量的黑洞)名列榜首(图1),... 详细信息

美国《科学新闻》(Science News)杂志网站在2021年12月20日的报道中,梳理了2021年度令人惊奇的六大科学纪录,其中天文学家发现的迄今最古老的巨大黑洞(即红移为7.642的类星体J0313-1806中心质量为16亿倍太阳质量的黑洞)名列榜首(图1),这些新发现拓展了科学研究的极限和人类的想象力.本文将对这一发现迄今最古老巨大黑洞的研究过程及其科学意义进行简要解读,并对今后相关研究进行展望.

关键词：类星体黑洞太阳质量杂志网站科学研究想象力

Discovery of six high-redshift quasars with the Lijiang 2.4 m telescope and the Multiple Mirror Telescope

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Research in Astronomy and Astrophysics 2012年第9期12卷 1185-1190页

作者： xue-bing wu Wen-Wen Zuo Qian Yang Wei-Min Yi Chen-Wei Yang Wen-Juan Liu Peng Jiang Xin-Wen Shu Hong-Yan Zhou Department of Astronomy Peking University Beijing 100871 China wuxb @*** National Astronomical Observatories / Yunnan Astronomical Observatory Chinese Academy ofSciences Kunming 650011 China Key Laboratory for Research in Galaxies and Cosmology The University of Science andTechnology of China Chinese Academy of Sciences Hefei 230026 China Polar Research Institute of China Shanghai 200136 China

Quasars with redshifts greater than 4 are rare, and can be used to probe the structure and evolution of the early universe. Here we report the discovery of six new quasars with i-band magnitudes brighter than 19.5 and redshifts between 2.4 and 4.6 from spectroscopy with the Yunnan Faint Object Spectrograph and Camera (YFOSC) at the Lijiang 2.4 m telescope in February, 2012. These quasars are in the list of z > 3.6 quasar candidates selected by using our proposed J K/i Y criterion and the photometric redshift estimations from the SDSS optical and UKIDSS near-IR photometric data. Nine candidates were observed by YFOSC, and five among six new quasars were identified as z > 3.6 quasars. One of the other three objects was identified as a star and the other two were unidentified due to the lower signal-to-noise ratio of their spectra. This is the first time that z > 4 quasars have been discovered using a telescope in China. Thanks to the Chinese Telescope Access Program (TAP), the redshift of 4.6 for one of these quasars was confirmed by the Multiple Mirror Telescope (MMT) Red Channel spectroscopy. The continuum and emission line properties of these six quasars, as well as their central black hole masses and Eddington ratios, were obtained.

关键词： quasars: general — quasars: emission lines — galaxies: active — galax- ies: high-redshift

Efficacy and Safety of Zihua Wenfei Zhisou Granule in Treatment of Postinfectious Cough: A Multicenter, Randomized, Double-Blind, Placebo-Controlled, Phase Ⅱ Clinical Trial

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Chinese Journal of Integrative Medicine 2025年第1期31卷 3-10页

作者： LI Ting LIU xue-mei YANG Mei wu Yan-qing LIU Wei MAO bing JIANG Hong-li Division of Pulmonary Medicine Department of Internal MedicineInstitute of Integrated Traditional Chinese and Western MedicineWest China HospitalSichuan UniversityChengdu610041China Department of Pulmonary Diseases State Key Laboratory of Biotherapy of ChinaWest China HospitalSichuan UniversityChengdu610041China

Objective: To evaluate the efficacy and safety of Chinese medicine(CM) Zihua Wenfei Zhisou Granule(ZWZG) in postinfectious cough(PIC) patients with CM syndrome of wind-cold invading Fei(Lung,WCIF). Methods: This is a multicenter, randomized, double-blind, parallel-group, placebo-controlled phase Ⅱclinical trial. PIC patients with WCIF syndrome were recruited from the Respiratory Departments in 6 hospitals across China between March 2019 and December 2020. Eligible patients were randomly assigned to group A(ZWZG-matched placebo 15 g), group B(active ZWZG 15 g), and group C(active ZWZG 10 g plus ZWZGmatched placebo 5 g) in a 1:1:1 ratio. All medications were taken orally 3 times daily for 14 consecutive days. The primary outcomes were cough relief rate and cough disappearance rate. The secondary outcomes included time to cough relief, time to cough disappearance, and changes in cough symptom score(CSS), cough Visual Analog Scale(VAS) value, Cough-Specific Quality of Life Questionnaire(CQLQ) score, and CM syndrome score from baseline(day 0) to post-treatment(day 14). Adverse events(AEs) in each group were recorded. Results: A total of 198 patients were included in the full analysis set(FAS) and safety analysis set(SS), while 183 were enrolled in the per-protocol analysis set(PPS). In the FAS population, the cough relief rate was 47.76%, 90.77% and 84.85%in groups A, B, and C, respectively;while the cough disappearance rate was 31.34%, 72.31% and 68.18%,respectively. The cough relief rates and cough disappearance rates in groups B and C were significantly higher than group A(P<0.0001). Both the median time to cough relief and cough disappearance in groups B and C were shorter than group A(P<0.0001). Compared with group A, groups B and C showed significantly greater improvements from baseline to post-treatment in CSS during daytime and nighttime as well as VAS(P<0.05).There were no significant differences in changes from baseline to post-treatment in CQLQ and CM syndrome

关键词： postinfectious cough Zihua Wenfei Zhisou Granule randomized controlled trial Chinese medicine

A search for double-peaked narrow emission line galaxies and AGNs in the LAMOST DR1

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Research in Astronomy and Astrophysics 2014年第10期14卷 1234-1250页

作者： Zhi-Xin Shi A-Li Luo Georges Comte Xiao-Yan Chen Peng Wei Yong-Heng Zhao Fu-Chao wu Yan-Xia Zhang Shi-Yin Shen Ming Yang Hong wu xue-bing wu Hao-Tong Zhang Ya-Juan Lei Jian-Nan Zhang Ting-Gui Wang Ge Jin Yong Zhang Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences National Laboratory of Pattern Recognition Institute of AutomationChinese Academy of Sciences University of Chinese Academy of Sciences Aix-Marseille Universite&CNRS Institut PytheasLAM(Laboratoire d'Astrophysique de Marseille)UMR7326F-13388 Marseille Shanghai Astronomical Observatory Chinese Academy of Sciences Department of Astronomy Peking University University of Science and Technology of China Nanjing Institute of Astronomical Optics & Technology National Astronomical ObservatoriesChinese Academy of Sciences

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope （LAMOST） has released more than two million spectra, which provide the opportunity to search for double-peaked narrow emission line （NEL） galaxies and active galactic nuclei （AGNs）. The double-peaked narrow-line profiles can be well modeled by two velocity components, respectively blueshifted and redshifted with respect to the sys- temic recession velocity. This paper presents 20 double-peaked NEL galaxies and AGNs found from LAMOST DR1 using a search method based on a multi-Gaussian fit of the narrow emission lines. Among them, ten have already been published by other authors, either listed as genuine double-peaked NEL objects or as asymmetric NEL objects, and the remaining ten are original discoveries. We discuss some pos- sible origins for the double-peaked narrow-line features, such as interaction between jet and narrow line regions, interaction with companion galaxies, and black hole bina- ries. Spatially resolved optical imaging and/or follow-up observations in other spectral bands are needed to further discuss the physical mechanisms at work.

关键词： galaxies emission lines -- quasars emission lines -- methods dataanalysis

Mechanisms behind the surprising observation of supra-thermal ions in NIF’s fusion burning plasmas

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Science Bulletin 2025年第3期70卷 359-364页

作者： Yuhan xue Dong wu Jie Zhang Key Laboratory for Laser Plasmas and Department of Physics and Astronomy Collaborative Innovation Center of IFSA(CICIFSA)Shanghai Jiao Tong UniversityShanghai 200240China Institute of Physics Chinese Academy of SciencesBeijing 100190China

Although ignition had been achieved at the National Ignition Facility(NIF),recent observations of the experiments indicate novel physics that beyond theoretical predictions emerge,e.g.,the neutron analysis of experiments has revealed deviations from the Maxwellian distributions in ion relative kinetic energies of burning plasmas,with the surprising emergence of supra-thermal deuterium and tritium(DT)ions that fall outside the predictions of macroscopic statistical hydrodynamic *** our newly developed hybrid-particle-in-cell code,incorporating the newly-proposed model of large-angle collisions,we infer that that this could be attributed to the increased significance of large-angle collisions among DT ions andα-particles in the burning *** and unprecedented kinetic investigations into the implications of large-angle collisions in the burning plasma have yielded several key findings,including an ignition moment promotion by~10 ps,the presence of supra-thermal ions below an energy threshold,and approximately twice the expected deposition ofα-particles *** rationality of our findings is confirmed through the congruency between the neutron spectral moment analyses conducted by the NIF and our kinetic simulations,both highlighting progressively widening disparities between neutron spectral moment analyses and hydrodynamics predictions,which becomes more pronounced as the yield *** kinetic simulations with large-angle collisions not only provide novel insights for experiment interpretation but also open new research opportunities for the largely unexplored regime of the nuclear burning plasmas,which are distinguished by their exceptionally high energy densities and hold immense potential for illuminating the intricate physics that underpins the evolution of the early universe.

关键词： lon kinetics Supra-thermal ions Large-angle collisions Non-equilibrium ignition Inertial confinement fusion Burning plasmas

The galaxy luminosity function in the LAMOST Complete Spectroscopic Survey of Pointing Area at the Southern Galactic Cap

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Research in Astronomy and Astrophysics 2019年第8期19卷 69-80页

作者： Pin-Song Zhao Hong wu Cong Kevin Xu Ming Yang Fan Yang Yi-Nan Zhu Man I Lam Jun-Jie Jin Hai-Long Yuan Hao-Tong Zhang Shi-Yin Shen Jian-Rong Shi A-Li Luo xue-bing wu Yong-Heng Zhao Yi-Peng Jing Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing100049China Chinese Academy of Sciences South America Center for Astronomy China-Chile Joint Center for AstronomyCamino El Observatorio1515Las CondesSantiagoChile IAASARS National Observatory of AthensVas.Pavlou&I.MetaxaPenteli15236Greece Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy ofSciencesShanghai200030China Department of Astronomy School of PhysicsPeking UniversityBeijing100871China School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai200240China

We present optical luminosity functions(LFs) of galaxies in the0.1 g,0.1 r,0.1 i bands, calculated using data in40 deg2 sky area of the LAMOST Complete Spectroscopic Survey of Pointing Area(LaCoSSPAr) in the Southern Galactic Cap. Redshifts for galaxies brighter than r = 18.1 were obtained mainly with LAMOST. In each band, LFs derived using both parametric and non-parametric maximum likelihood methods agree well with each other. In the0.1 r band, our fitting parameters of the Schechter function are φ*=(1.65 ± 0.36) × 10-2 h3 Mpc-3, M*=-20.69 ± 0.06 mag and α =-1.12 ± 0.08,which agree with previous studies. Separate LFs are also derived for emission line galaxies and absorption line galaxies. The LFs of absorption line galaxies show a dip at0.1 r 18.5 and can be fitted well by a double-Gaussian function, suggesting a bimodality in passive galaxies.

关键词： galaxies:luminosity function,mass function galaxies:statistics galaxies:distances and redshifts

Grounded-source short offset transient electromagnetic method:Theory and applications in deep mineral exploration

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Science China Earth Sciences 2025年第2期68卷 626-638页

作者： Guoqiang xue Xin wu Weiying CHEN Nannan ZHOU Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The Transient Electromagnetic(TEM)method is a critical geophysical technique for subsurface exploration of metal ore bodies,primarily utilizing either loop or grounded *** Long Offset Transient Electromagnetic(LOTEM)method employs a grounded-source transmitter,relying on a far-source observation mode and plane wave approximation for ***,LOTEM's far-source configuration weakens signal strength,and the plane wave approximation reduces precision,limiting effective detection depth to approximately 1000 m with a comprehensive error of about 15%.Recently,we have developed the grounded-source Short Offset Transient Electromagnetic(SOTEM)method,achieving greater detection depth and accuracy within the 500–2000 m depth range,a crucial interval for mineral resource *** study explores the theoretical framework,instrumentation,data processing,and field applications of *** on a point charge element model,SOTEM accurately computes surface wave effects in EM field calculations,optimized for near-source ***-power,high-resolution,wide-bandwidth exploration equipment and an advanced three-dimensional hybrid inversion technique were also developed to enhance the method's *** of SOTEM to the deep exploration of the Zhou'an Ni-Cu-PGE deposit in Henan Province yielded high-resolution imaging of conductivity structures to about 2.5 km *** results,consistent with existing drill data,delineated mineralized ore bodies from surrounding formations,identified zones of mineralization potential,and suggested extensive resource prospects in the region.

关键词： Far-source observation Plane wave model approximation Grounded-source short-offset transient electromagnetic method Wide-bandwidth exploration equipment Three-dimensional hybrid inversion

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