|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Commissioning progress of the FAST显示文摘The Five-hundred-meter Aperture Spherical radio Telescope(FAST) was completed with its main structure installed on September 25, 2016, after which it entered the commissioning phase. This paper aims to introduce the commissioning progress of the FAST over the past two years. To improve its operational reliability and ensure effective observation time, FAST has been equipped with a real-time information system for the active reflector system and hierarchical commissioning scheme for the feed support system, which ultimately achieves safe operation of the two systems. For meeting the high-performance indices, a highprecision measurement system was set up based on the effective control methods that were implemented for the active reflector system and feed support system. Since the commissioning of the FAST, a low-frequency ultra-wideband receiver and 19-beam1.05-1.45 GHz receiver have been mainly used. Telescope efficiency, pointing accuracy, and system noise temperature were completely tested and ultimately achieved the acceptance indices of the telescope. The FAST has been in the process of national acceptance preparations and has begun to search for pulsars. In the future, it will still strive to improve its capabilities and expand its application prospects. | Peng Jiang YouLing Yue HengQian Gan Rui Yao Hui Li GaoFeng Pan JingHai Sun DongJun Yu HongFei Liu NingYu Tang Lei Qian JiGuang Lu Jun Yan Bo Peng ShuXin Zhang QiMing Wang Qi Li Di Li | 2019 | Science China(Physics,Mechanics & Astronomy)2019,62,5: | 11 |
| 2 | The first pulsar discovered by FAST显示文摘To assist with the commissioning [1] of the Five-hundredmeter Aperture Spherical radio Telescope (FAST), we performed a pulsar search, with the primary goal of developing and testing the pulsar data acquisition and processing pipelines. We tested and used three pipelines, two (Pl and P2 hereafter) searched for the periodic signature of pulsars whereas the other one was used to search for bright single pulses (P3 hereafter). | Lei Qian ZhiChen Pan Di Li George Hobbs WeiWei Zhu Pei Wang ZhiJie Liu YouLing Yue Yan Zhu HongFei Liu DongJun Yu JingHai Sun Peng Jiang GaoFeng Pan Hui Li HengQian Gan Rui Yao XiaoYao Xie Fernando Camilo Andrew Cameron Lei Zhang Shen Wang FAST Collaboration | 2019 | Science China(Physics,Mechanics & Astronomy)2019,62,5: | 3 |
| 3 | Timing and Single-pulse Study of Pulsar J1909+0122 Discovered by CRAFTS显示文摘We report the discovery of PSR J1909+0122 by the Five-hundred-meter Aperture Spherical Radio Telescope(FAST)as part of the Commensal Radio Astronomy FAST Survey.PSR J1909+0122 has a spin period of 1.257 s and a dispersion measure of 186.2 pc cm^(-3).The averaged pulse profile shows two distinct components.We performed a single-pulse study based on a one-hour observation at 1.25 GHz on 2021 August 23.We used a threshold of 5σ_(ep) to measure the nulling fraction(NF)as 63%±1.5%.The longitude-resolved fluctuation spectra and fast Fourier transform spectra of the binary sequences revealed the quasi-periodicity of nulling with a period of 30 rotation periods.We examined the reliability of the periodicity by comparing it to random noise injection.The NF,E,and modulation periodicity P_(M) of PSR J1909+0122 were compared with other periodic nulling pulsars,showing that the source of J1909+0122 has the second largest NF in the population.Long-term timing observations over six months were used to derive the phase-connected ephemeris of this pulsar.The measured P and P values disfavor dipolar geometry for polar gap models,and the prediction for a space-charge-limited flow model in the case of inverse Compton scattering is only just above the death line.In this work,PSR J1909+0122 has revealed possible correlations between nulling behavior and pulsar properties,which will help to shed light on the pulsar emission mechanism and its temporal evolution in future observations. | Yutong Chen Pei Wang Di Li Erbil Gügercinoğlu Rushuang Zhao Lingqi Meng Jianping Yuan Jiarui Niu Weiwei Zhu Yi Feng Chenchen Miao Chenhui Niu Qingdong Wu Na Wang Shen Wang Xiaoyao Xie Mengyao Xue Jumei Yao Mao Yuan Shanping You Xuhong Yu Youling Yue Jie Zhang Junshuo Zhang Lei Zhang Yabiao Wang Zhenye Gan Yuxi Li Zhongyi Sun Chengjie Wang | 2023 | Research in Astronomy and Astrophysics2023,23,8: | 0 |
| 4 | Regioregular Non-Fused Polymerized Small Molecular Acceptors Enabling Efficient All-Polymer Solar Cells显示文摘Comprehensive Summary The regioregularity induced by the isomers of the end-groups has been widely recognized as a key factor that determines the photovoltaic properties of polymerized small molecular acceptors(PSMAs)in all-polymer solar cells(all-PSCs).However,the influence of regioregularity on the photovoltaic properties of non-fused PSMAs has not been explored yet.In this contribution,two regioregular non-fused PSMAs,PFBTz-T-γand PFBTz-T-δ,were synthesized for the first time by using the monomers with isomeric pure end-groups.Compared with PFBTz-T-δ,PFBTz-T-γhas more compact and more ordered packing in solid state,which results in a more red-shifted optical absorption and a higher electron mobility.More remarkably,PFBTz-T-γand PFBTz-T-δexhibited huge difference in photovoltaic performance in all-PSCs,which offered the power conversion efficiencies(PCEs)of 9.72%and 0.52%,respectively.Further studies have unveiled that the higher PCE of PFBTz-T-γis due to more efficient exciton dissociation,higher and more balanced electron/hole mobility,and less charge recombination as a result of favorable morphology of the blend film.This work demonstrates that the development of regioregular non-fused PSMAs by tuning the polymerization sites is an effective strategy for obtaining high-efficiency all-PSCs. | Baoqi Wu Youle Li Shizeng Tian Yue Zhang Langheng Pan Kangzhe Liu Mingqun Yang Fei Huang Yong Cao Chunhui Duan | 2023 | Chinese Journal of Chemistry2023,41,7: | 0 |
| 5 | FAST discovery of an extremely radio-faint millisecond pulsar from the Fermi-LAT unassociated source 3FGL J0318.1+0252显示文摘High sensitivity radio searches of unassociated γ-ray sources have proven to be an effective way of finding new pulsars. Using the Five-hundred-meter Aperture Spherical radio Telescope(FAST) during its commissioning phase, we have carried out a number of targeted deep searches of Fermi Large Area Telescope(LAT) γ-ray sources. On February 27, 2018 we discovered an isolated millisecond pulsar(MSP), PSR J0318+0253, coincident with the unassociated γ-ray source 3 FGL J0318.1+0252. PSR J0318+0253 has a spin period of 5.19 ms, a dispersion measure(DM) of 26 pc cm-3 corresponding to a DM distance of about 1.3 kpc, and a period-averaged flux density of(~11±2) μJy at L-band(1.05-1.45 GHz). Among all high energy MSPs, PSR J0318+0253 is the faintest ever detected in radio bands, by a factor of at least ~4 in terms of L-band fluxes. With the aid of the radio ephemeris, an analysis of 9.6 years of Fermi-LAT data revealed that PSR J0318+0253 also displays strong γ-ray pulsations. Follow-up observations carried out by both Arecibo and FAST suggest a likely spectral turn-over around 350 MHz. This is the first result from the collaboration between FAST and the Fermi-LAT teams as well as the first confirmed new MSP discovery by FAST, raising hopes for the detection of many more MSPs. Such discoveries will make a significant contribution to our understanding of the neutron star zoo while potentially contributing to the future detection of gravitational waves, via pulsar timing array(PTA) experiments. | Pei Wang Di Li Colin J.Clark Pablo M.Saz Parkinson Xian Hou Weiwei Zhu Lei Qian Youling Yue Zhichen Pan Zhijie Liu Xuhong Yu Shanping You Xiaoyao Xie Qijun Zhi Hui Zhang Jumei Yao Jun Yan Chengmin Zhang Kwok Lung Fan Paul S.Ray Matthew Kerr David A.Smith Peter F.Michelson Elizabeth C.Ferrara David J.Thompson Zhiqiang Shen Na Wang FAST&Fermi-LAT Collaboration | 2021 | Science China(Physics,Mechanics & Astronomy)2021,64,12: | 0 |
| 6 | Study of three rotating radio transients with FAST显示文摘Rotating radio transients(RRATs) are peculiar astronomical objects whose emission mechanism remains under investigation.In this paper, we present observations of three RRATs, J1538+2345, J1854+0306 and J1913+1330, carried out with the Fivehundred-meter Aperture Spherical radio Telescope(FAST). Specifically, we analyze the mean pulse profiles and temporal flux density evolutions of the RRATs. Owing to the high sensitivity of FAST, the derived burst rates of the three RRATs are higher than those in previous reports. RRAT J1854+0306 exhibited a time-dynamic mean pulse profile, whereas RRAT J1913+1330 showed distinct radiation and nulling segments on its pulse intensity trains. The mean pulse profile variation with frequency is also studied for RRAT J1538+2345 and RRAT J1913+1330, and the profiles at different frequencies could be well fitted with a cone-core model and a conal-beam model, respectively. | JiGuang Lu Bo Peng Kuo Liu Peng Jiang YouLing Yue Meng Yu Ye-Zhao Yu FeiFei Kou Lin Wang FAST Collaboration | 2019 | Science China(Physics,Mechanics & Astronomy)2019,62,5: | 0 |
| 7 | The radiation structure of PSR B2016+28 observed with FAST显示文摘With the largest dish Five-hundred-meter Aperture Spherical radio Telescope(FAST), both the mean and single pulses of PSR B2016+28, especially including the single-pulse structure, are investigated in detail in this study. The mean pulse profiles at different frequencies can be well fitted in a conal model, and the peak separation of intensity-dependent pulse profiles increases with intensity. The integrated pulses are obviously frequency dependent(pulse width decreases by ~20% as frequency increases from 300 to 750 MHz), but the structure of single pulses changes slightly(the corresponding correlation scale decreases by only~1%). This disparity between mean and single pulses provides independent evidence for the existence of the RS-type vacuum inner gap, indicating a strong bond between particles on the pulsar surface. Diffused drifting sub-pulses are analyzed. The results show that the modulation period along pulse series(P_3) is positively correlated to the separation between two adjacent sub-pulses(P_2). This correlation may hint a rough surface on the pulsar, eventually resulting in the irregular drift of sparks. All the observational results may have significant implications in the dynamics of pulsar magnetosphere and are discussed extensively in this paper. | JiGuang Lu Bo Peng RenXin Xu Meng Yu Shi Dai WeiWei Zhu Ye-Zhao Yu Peng Jiang YouLing Yue Lin Wang FAST Collaboration | 2019 | Science China(Physics,Mechanics & Astronomy)2019,62,5: | 0 |
| 8 | Status and perspectives of the CRAFTS extra-galactic HI survey显示文摘The Five-hundred-meter Aperture Spherical radio Telescope(FAST) is expected to complete its commissioning in 2019. FAST will soon begin the Commensal Radio Astronomy FasT Survey(CRAFTS), a novel and unprecedented commensal drift scan survey of the entire sky visible from FAST. The goal of CRAFTS is to cover more than 20000 deg2 and reach redshift up to about 0.35. We provide empirical measurements of the beam size and sensitivity of FAST across the 1.05 to 1.45 GHz frequency range of the FAST L-band array of 19-beams(FLAN). Using a simulated HI-galaxy catalogue based on the HI Mass Function(HIMF), we estimate the number of galaxies that CRAFTS may detect. At redshifts below 0.35, over 6 × 105 HI galaxies may be detected. Below the redshift of 0.07, the CRAFTS HIMF will be complete above a mass threshold of 109.5 M⊙. FAST will be able to investigate the environmental and redshift dependence of the HIMF to an unprecedented depth, shedding light onto the missing baryon and missing satellite problems. | Kai Zhang JingWen Wu Di Li Marko Krco Lister Staveley-Smith NingYu Tang Lei Qian MengTing Liu ChengJin Jin YouLing Yue Yan Zhu HongFei Liu DongJun Yu JingHai Sun GaoFeng Pan Hui Li HengQian Gan Rui Yao FAST Collaboration | 2019 | Science China(Physics,Mechanics & Astronomy)2019,62,5: | 0 |
| 9 | Polythiophene solar cells processed from non-halogenated solvent with 15.68%efficiency显示文摘Polythiophenes(PTs)are prospective polymer donors for large-scale manufacturing and industrialization owing to their simple structures and low synthetic cost.However,the fabrication of PT solar cells depends on highly toxic chlorinated solvents,and less research has been done on the use of more environmentally friendly non-halogenated solvents.Herein,highly efficient PT solar cells based on top-performance polythiophene,P5TCN-F25,processed from a non-halogenated solvent are reported by delicate aggregation control.A power conversion efficiency of up to 15.68%was achieved by depositing the active layer from a hot o-xylene solution,which is the record efficiency of non-halogenated processed PT solar cells up to date.The appropriate solution temperature is beneficial to the formation of ordered polymer stacking and desirable phase separation size,which thereby contributes to enhanced charge transfer efficiency,more balanced hole/electron mobility,and reduced trap-assisted recombination.These results provide valuable implications for improving the efficiency of PT solar cells via environmentallyfriendly processing. | Xiaoxin Tan Youle Li Xiyue Yuan Seoyoung Kim Yue Zhang Changduk Yang Fei Huang Yong Cao Chunhui Duan | 2023 | Science China Chemistry2023,66,8: | 0 |