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	An Ultralong-wavelength Sky Model with Absorption Effect 期刊论文 OAI收割 The Astrophysical Journal, 2021, 卷号: 914, 期号: 2 作者: Cong,Yanping; Yue,Bin; Xu,Yidong; Huang,Qizhi; Zuo,Shifan \| 收藏 \| 浏览/下载：43/0 \| 提交时间：2021/12/06 Radio continuum emission Interstellar emissions Galaxy structure H II regions Extragalactic radio sources
	A Large Population of Obscured AGN in Disguise as Low-luminosity AGN in Chandra Deep Field South 期刊论文 OAI收割 The Astrophysical Journal, 2020, 卷号: 897, 期号: 2 作者: Lambrides,Erini L.; Chiaberge,Marco; Heckman,Timothy; Gilli,Roberto; Vito,Fabio \| 收藏 \| 浏览/下载：10/0 \| 提交时间：2021/12/06 Active galactic nuclei AGN host galaxies Active galaxies X-ray active galactic nuclei Optical observation Infrared sources Extragalactic radio sources Surveys
	The Giant Radio Array for Neutrino Detection (GRAND): Science and design 期刊论文 OAI收割 SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY, 2020, 卷号: 63, 期号: 1, 页码: 43 作者: Alvarez-Muniz, Jaime; Batista, Rafael Alves; Balagopal, Aswathi, V; Bolmont, Julien; Bustamante, Mauricio \| 收藏 \| 浏览/下载：26/0 \| 提交时间：2021/09/26 radio telescopes neutrinos in astronomical observations cosmic rays in astronomical observations radiowave radiation: sources galactic and extragalactic cosmic rays: galactic and extragalactic
	No pulsed radio emission during a bursting phase of a Galactic magnetar 期刊论文 OAI收割 Nature, 2020, 卷号: 587, 页码: 63-65 作者: HXMT \| 收藏 \| 浏览/下载：44/0 \| 提交时间：2022/02/08 Astrophysics - High Energy Astrophysical Phenomena Abstract: Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances^1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources^4-13, but no convincing evidence has been collected so far¹⁴. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft íray bursts¹⁵. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft íray/hard-X-ray flare^18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-íray repeater (SGR) bursts were detected in íray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.
	Quasi-simultaneous VLBI and RATAN-600 observations of active galactic nuclei 期刊论文 OAI收割 ASTRONOMY REPORTS, 2004, 卷号: 48, 期号: 11, 页码: 900-908 作者: Pushkarev, AB; Kovalev, YY; Molotov, IE; Nechaeva, MB; Gorshenkov, YN 收藏 \| 浏览/下载：36/0 \| 提交时间：2013/03/06 BL LACERTAE OBJECTS EXTRAGALACTIC RADIO-SOURCES COMPLETE SAMPLE LAC OBJECTS EMISSION SPECTRA GHZ
	A statistical study of the southern 5 GHz VLBI survey 期刊论文 OAI收割 CHINESE ASTRONOMY AND ASTROPHYSICS, 1998, 卷号: 22, 期号: 3, 页码: 275-279 作者: Shen, ZQ; Wan, TS 收藏 \| 浏览/下载：13/0 \| 提交时间：2015/09/02 extragalactic radio sources VLBI surveys statistical analysis