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    题名 作者 年代 出处 被引量
1Optical observations of LIGO source GW 170817 by the Antarctic Survey Telescopes at Dome A,Antarctica显示文摘The LIGO detection of gravitational waves(GW) from merging black holes in 2015 marked the beginning of a new era in observational astronomy. The detection of an electromagnetic signal from a GW source is the critical next step to explore in detail the physics involved. The Antarctic Survey Telescopes(AST3),located at Dome A, Antarctica, is uniquely situated for rapid response time-domain astronomy with its continuous night-time coverage during the austral winter. We report optical observations of the GW source(GW 170817) in the nearby galaxy NGC 4993 using AST3. The data show a rapidly fading transient at around 1 day after the GW trigger, with the i-band magnitude declining from 17:23 ± 0:13 magnitude to 17:72 ± 0:09 magnitude in ~1:8 h. The brightness and time evolution of the optical transient associated with GW 170817 are broadly consistent with the predictions of models involving merging binary neutron stars. We infer from our data that the merging process ejected about ~10^(-2) solar mass of radioactive material at a speed of up to 30% the speed of light.lei hu xuefeng wu igor andreoni michael c.b.ashley jeff cooke xiangqun cui fujia du zigao dai bozhong gu yi hu haiping lu xiaoyan li zhengyang li ensi liang liangduan liu bin ma zhaohui shang tianrui sun n.b.suntzeff charling tao syed a.uddin lifan wang xiaofeng wang haikun wen di xiao jin xu ji yang shihai yang xiangyan yuan hongyan zhou hui zhang jilin zhou zonghong zhu 2017Science Bulletin2017,62,21:6
2The physics of fast radio bursts显示文摘In 2007, a very bright radio pulse was identified in the archival data of the Parkes Telescope in Australia, marking the beginning of a new research branch in astrophysics. In 2013, this kind of millisecond bursts with extremely high brightness temperature takes a unified name, fast radio burst(FRB). Over the first few years, FRBs seemed very mysterious because the sample of known events was limited. With the improvement of instruments over the last five years, hundreds of new FRBs have been discovered.The field is now undergoing a revolution and understanding of FRB has rapidly increased as new observational data increasingly accumulate. In this review, we will summarize the basic physics of FRBs and discuss the current research progress in this area.We have tried to cover a wide range of FRB topics, including the observational property, propagation effect, population study,radiation mechanism, source model, and application in cosmology. A framework based on the latest observational facts is now under construction. In the near future, this exciting field is expected to make significant breakthroughs.Di Xiao FaYin Wang ZiGao Dai 2021Science China(Physics,Mechanics & Astronomy)2021,64,4:2
3Constraining ΩM and dark energy with gamma-ray bursts显示文摘Dai Zigao Liang Enwei Xu Dong 2004ApJ L2004,612,:1
4Science with the 2.5-meter Wide Field Survey Telescope(WFST)显示文摘The Wide Field Survey Telescope(WFST) is a dedicated photometric surveying facility being built jointly by University of Science and Technology of China(USTC) and the Purple Mountain Observatory(PMO). It is equipped with a 2.5-meter diameter primary mirror, an active optics system, and a mosaic CCD camera with 0.73 gigapixels on the primary focal plane for highquality image capture over a 6.5-square-degree field of view. The installation of WFST near the summit of Saishiteng mountain in the Lenghu region is scheduled in summer of 2023, and the operation is planned to start three months later. WFST will scan the northern sky in four optical bands(u, g, r and i) at cadences from hourly/daily in the deep high-cadence survey(DHS) program, to semi-weekly in the wide field survey(WFS) program. During a photometric night, a nominal 30 s exposure in the WFS program will reach a depth of 22.27, 23.32, 22.84, and 22.31(AB magnitudes) in these four bands, respectively, allowing for the detection of a tremendous amount of transients in the low-z universe and a systematic investigation of the variability of Galactic and extragalactic objects. In the DHS program, intranight 90 s exposures as deep as 23(u) and 24 mag(g), in combination with target of opportunity follow-ups, will provide a unique opportunity to explore energetic transients in demand for high sensitivities, including the electromagnetic counterparts of gravitational wave events, supernovae within a few hours of their explosions,tidal disruption events and fast, luminous optical transients even beyond redshift of unity. In addition, the final 6-year co-added images, anticipated to reach g■25.8 mag in WFS or 1.5 mags deeper in DHS, will be of fundamental importance to general Galactic and extragalactic science. The highly uniform legacy surveys of WFST will serve as an indispensable complement to those of the Vera C. Rubin Observatory's Legacy Survey of Space and Time(LSST) that monitors the southern sky.Tinggui Wang Guilin Liu Zhenyi Cai Jinjun Geng Min Fang Haoning He Ji-an Jiang Ning Jiang Xu Kong Bin Li Ye Li Wentao Luo Zhizheng Pan Xuefeng Wu Ji Yang Jiming Yu Xianzhong Zheng Qingfeng Zhu Yi-Fu Cai Yuanyuan Chen Zhiwei Chen Zigao Dai Lulu Fan Yizhong Fan Wenjuan Fang Zhicheng He Lei Hu Maokai Hu Zhiping Jin Zhibo Jiang Guoliang Li Fan Li Xuzhi Li Runduo Liang Zheyu Lin Qingzhong Liu Wenhao Liu Zhengyan Liu Wei Liu Yao Liu Zheng Lou Han Qu Zhenfeng Sheng Jianchun Shi Yiping Shu Zhenbo Su Tianrui Sun Hongchi Wang Huiyuan Wang Jian Wang Junxian Wang Daming Wei Junjie Wei Yongquan Xue Jingzhi Yan Chao Yang Ye Yuan Yefei Yuan Hongxin Zhang Miaomiao Zhang Haibin Zhao Wen Zhao 2023Science China(Physics,Mechanics & Astronomy)2023,66,10:1
5The prompt phase mechanism of gamma-ray bursts显示文摘Gamma-ray bursts(GRBs)are flashes of ganima-rays occurring at cosmological distances(for a recent review see^([1])).They are divided into two classes based on their prompt emission durations:short-duration(<2 seconds)hard-spectrum bursts and long-duration soft-spectmm bursts(>2 seconds).The observations(including discoveries of both the gravitational wave event GW170817 from an inspiral of two neutron stars and its electromagnetic counterparts)indicate that long-duration GRBs result from core collapses of massive stars and short-duration GRBs are produced from mergers of neutron star-neutron star binaries or black hole-neutron star binaries.Zigao Dai 2021Frontiers of physics2021,16,1:0
6An unexpected X-ray transient favors very stiff neutron-star matter显示文摘Short-duration gamma-ray bursts (SGRBs) are mysterious gamma-ray flashes with durations less than two seconds, which occur at the cosmological distances. Some of them usually not only have very tenuous medium gases and old host galaxies but also are in the outskirts of the galaxies, suggesting an origin of binary neutron star (NS) mergers (1)This origin was confirmed undoubtedly thanks to the discoveries of a gravitational wave event namedGW170817 and its electromagnetic counterparts (an SGRB, a multiwavelengthkilo-nova, and a broadband afterglow) [2].Zigao Dai 2019Science Bulletin2019,64,20:0
7An Intermediate-field Fast Radio Burst Model and the Quasi-periodic Oscillation显示文摘Quasi-periodic oscillation(QPO)signals are discovered in some fast radio bursts(FRBs)such as FRB 20191221A,as well as in the X-ray burst associated with the galactic FRB from SGR 1935+2154.We revisit the intermediatefield FRB model where the radio waves are generated as fast-magnetosonic waves through magnetic reconnection near the light cylinder.The current sheet in the magnetar wind is compressed by a low frequency pulse emitted from the inner magnetosphere to trigger magnetic reconnection.By incorporating the wave dynamics of the magnetosphere,we demonstrate how the FRB frequency,the single pulse width,and luminosity are determined by the period,magnetic field,QPO frequency and quake energetics of the magnetar.We find that this model can naturally and self-consistently interpret the X-ray/radio event from SGR 1935+2154 and the QPO in FRB20191221A.It can also explain the observed wide energy range of repeating FRBs in a narrow bandwidth.Jie-Shuang Wang Xinyu Li Zigao Dai Xuefeng Wu 2023Research in Astronomy and Astrophysics2023,23,3:0
8Design,synthesis and biological evaluation of novel phthalazinone acridine derivatives as dual PARP and Topo inhibitors for potential anticancer agents显示文摘In this study,we designed and synthesized a series of phthalazinone acridine derivatives as dual PARP and Topo inhibitors.MTT assays indicated that most of the compounds significantly inhibited multiple cancer cells proliferation.In addition,all the compounds displayed Topo Ⅱ inhibition activity at 10 mol/L,and also possessed good PARP-1 inhibitory activities.Subsequent mechanistic studies showed that compound 9 a induced remarkable apoptosis and caused prominent S cell cycle arrest in HCT116 cells.Our study suggested that 9 a inhibiting Topo and PARP concurrently can be a potential lead compound for cancer therapy.Qiuzi Dai Jiwei Chen Chunmei Gao Qinsheng Sun Zigao Yuan Yuyang Jiang 2020Chinese Chemical Letters2020,31,2:0
9Design, synthesis and antitumor evaluations of nucleoside base hydroxamic acid derivatives as DNMT and HDAC dual inhibitors显示文摘DNA methyl transferase(DNMT) and histone deacetylase(HDAC) are well recognized epigenetic targets for discovery of antitumor agents.In this study,we designed and synthesized a series of nucleoside base hydroxamic acid derivatives as DNMT and HDAC dual inhibitors.MTT assays and enzymatic inhibitory activity tests indicated that compound 204 exhibited potent DNMT1 and HDAC1/6 inhibitory potency simultaneously in enzymatic levels and at cellular levels,inducing hypomethylation of p16 and hyperacetylation of histones H_(3) K9 and H4 K8.Besides,204 remarkably inhibited proliferation against cancer cells U937 by prompting G0/G1 cell cycle arrest.Molecular docking models explained the functional mechanism of 204 inhibiting DNMT1 and HDAC.Preliminary studies on metabolic profiles revealed that 204 showed desirable stability in liver microsomes.Our study suggested that 204 inhibiting DNMT and HDAC concurrently can be a potential lead compound for epigenetic cancer therapy.Qinsheng Sun Qiuzi Dai Cunlong Zhang Yan Chen Lei Zhao Zigao Yuan Yuyang Jiang 2021Chinese Chemical Letters2021,32,8:0
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