本帖最后由 gohomeman1 于 2010-6-1 21:01 编辑
http://www.fit.edu/newsroom/news/3917/supermassive_black_holes_may_frequently_roam_galaxy_centers/
Supermassive Black Holes May Frequently Roam Galaxy Centers
超级黑洞可能在星系中心“梦游”
05/25/2010
图说明：ACS的HRC通道拍摄的M87核心喷流。
MELBOURNE, FLA.—A team of astronomy researchers at Florida Institute of Technology and Rochester Institute of Technology in the United States and University of Sussex in the United Kingdom, find that the supermassive black hole (SMBH) at the center of the most massive local galaxy (M87) is not where it was expected. Their research, conducted using the Hubble Space Telescope (HST), concludes that the SMBH in M87 is displaced from the galaxy center.
佛罗里达州墨尔本市（在佛州东南部沿海），由佛罗里达理工学院（FIT）、美国罗切斯特国立理工学院（RIT）、英国萨塞克斯大学的研究者组成的天文学团队，发现在我们附近的巨椭圆星系M87中，超大质量黑洞（SMBH，超级黑洞）并不在预期的方位上。研究者使用哈勃太空望远镜（HST）观测发现：超级黑洞已经偏离M87的星系核心。
The most likely cause for this SMBH to be off center is a previous merger between two older, less massive, SMBHs. “We also find, however, that the iconic M87 jet may have pushed the SMBH away from the galaxy center,” said Daniel Batcheldor, Florida Tech assistant professor in the Department of Physics and Space Sciences, who led the investigation.
最大的可能是：现在的超级黑洞是以前2个老的SMBH合并产生的。研究团队领队、佛罗里达理工学院物理和太空科学系助理教授 Daniel Batcheldor说：“我们还发现，M87标志性的黑洞喷流可能把超级黑洞推向反方向。”
The study of M87 is part of a wider HST project directed by Andrew Robinson, professor of physics at RIT. “What may well be the most interesting thing about this work is the possibility that what we found is a signpost of a black hole merger, which is of interest to people looking for gravitational waves and for people modeling these systems as a demonstration that black holes really do merge,” says Robinson. “The theoretical prediction is that when two black holes merge, the newly combined black hole receives a ‘kick’ due to the emission of gravitational waves, which can displace it from the center of the galaxy.”
RIT物理学教授安德鲁.罗宾逊领导了一个广泛的哈勃项目，对M87的研究仅是其一部分。罗宾逊说：“这项工作最有趣的目标之一就是发现黑洞合并的证据，这对人们寻找引力波、建立物理模型、证明黑洞确实在合并都很有价值。理论预言，当两个黑洞合并时，新生黑洞会受到引力波的“反冲”，从而偏离星系的核心。”
David Merritt, professor of physics at RIT, adds: “Once kicked, a supermassive black hole can take millions or billions of years to return to rest, especially at the center of a large, diffuse galaxy like M87. So searching for displacements is an effective way to constrain the merger history of galaxies.”
RIT物理学教授大卫.梅里特补充道：“一次反冲后，超级黑洞可能会休眠数百万甚至十亿年，在M87这样巨大的椭圆星系中更是如此。因此，对于研究星系合并历史而言，这种效应导致的位移是很重要的途径。”
Jets, such as the one in M87, are commonly found in a class of objects called Active Galactic Nuclei. It is commonly believed that supermassive black holes can become active as a result of the merger between two galaxies, the infall of material into the center of the galaxy, and the subsequent merger between their black holes. Therefore, it is very possible that this finding could also be linked to how active galaxies—including quasars, the most luminous objects in the universe—are born and how their jets are formed.
像M87中这样的喷流，一般产生于活动星系核（AGN）这类天体中。一般认为，当两个星系合并时，大量物质会落入星系中心，然后两个超级黑洞会合并，这个过程中超级黑洞会变得非常活跃。因此，本发现很可能有助于了解包括类星体（宇宙中最亮的天体）在内的活动星系及其喷流的形成。
This research will be presented at the American Astronomical Society (AAS) Conference on May 25 in Miami, Fla. It will also be published in The Astrophysical Journal Letters peer-reviewed scientific journal.
2010.5.25，全美天文学大会（AAS）继续在佛罗里达州迈阿密市举行，会上公布了此发现。本文还将刊登在《天体物理学通讯期刊》内部预览本上。
Because many galaxies have similar properties to M87, it is likely that SMBHs are commonly offset from their host galaxy centers. The potential offsets, however, would be very subtle and researchers would rely on the Hubble Space Telescope to detect them.
许多星系经历过与M87类似的过程，因此它们的超级黑洞很可能也偏离星系核心。当然咯，这个偏离非常小，所以啦，研究者要借助哈勃太空望远镜去发现它们。
“Unfortunately, the highest spatial resolution camera onboard HST could not be revived during the recent servicing mission. This means we have to rely on the huge archive of HST data to find more of these vagrant SMBHs, as we did for M87,” added Batcheldor.
Batcheldor继续说道：“不幸的是，最新的哈勃维护任务中，高分辨率通道（ACS的HRC通道）的修复失败了。这意味着我们不得不在巨大的哈勃数据档案库中去寻找流浪的超级黑洞了，就像我们在M87中做的一样。”（题图是哈勃早期图像，HRC通道的0.025"分辨率比现在WFC3的UVIS通道的0.04"高得多——gohomeman1注）
Regardless of the displacement mechanism, the implication of this result is a necessary shift in the classic SMBH paradigm; no longer can it be assumed that all SMBHs reside at the centers of their host galaxies. This may result in some interesting impacts on a number of fundamental astronomical areas, and some interesting questions.
不管位移的机制是什么，本报告对超级黑洞研究而言都是必须考虑的：我们不能再假设超级黑洞就位于星系核的中心。这将改变多个天文学的基本常识，并带来一些新的有趣问题。
For example, how would an accreting (growing by the gravitational attraction of matter) or quiescent SMBH interact with the surrounding nuclear environment as it moves through the bulge? What are the effects on the standard orientation-based unified model of active galactic nuclei and how have dynamical models of the SMBH mass been centered if the SMBH is quiescent?
比如说：当超级黑洞在核球区漫游时，吸积过程（引力导致的物质积聚过程）将如何改变，休眠黑洞与周围的核球物质又将如何互动？在标准的活动星系核模型中，AGN的取向将如何改变？在休眠黑洞情形下，超级黑洞的质量积聚的动力学模式又如何？
Especially thought-provoking, added Eric Perlman, associate professor of physics and space sciences at Florida Tech, is that our own galaxy is expected to merge with the Andromeda galaxy in about three billion years. ”The result of that merger will likely be an active elliptical galaxy, similar to M87. Both our galaxy and Andromeda have SMBHs in their centers, so our result suggests that after the merger, the SMBH may wander in the galaxy’s nucleus for billions of years.”
FIT物理和太空科学系助理教授Eric Perlman补充道：“尤其发人深思的是，我们的银河系将在30亿年后与仙女座大星系（M31）合并。合并的结果很可能是像M87这样的活动椭圆星系。银河系和M31核心都有超级黑洞，因此我们推测合并后的超级大黑洞将在星系核心区域梦游数十亿年。”
David Axon, Dean of Mathematical and Physical Sciences at Sussex, concludes by saying that “In current galaxy formation scenarios galaxies are thought to be assembled by a process of merging. We should therefore expect that binary black holes and post coalescence recoiling black holes, like that in M87, are very common in the cosmos.“
萨塞克斯大学数学和物理系主任David Axon最后总结道：“按当前的星系演化理论，星系通过合并长大。因此我们预期，宇宙星系中存在一对超级黑洞或者像M87那样的合并后反冲位移黑洞，是极为普遍的。”
Researchers on the project are Daniel Batcheldor and Eric Perlman, Florida Tech; Andrew Robinson and David Merritt of RIT; and David Axon, dean of mathematical and physical sciences at University of Sussex in the United Kingdom and research professor at RIT. All are authors of the paper, “A Displaced Supermassive Black Hole in M87.”
本项目报告的标题为“超级黑洞在M87中梦游”。研究者兼报告作者为：
佛罗里达理工学院（FIT） Daniel Batcheldor、Eric Perlman；
美国罗切斯特国立理工学院（RIT） David Merritt；
英国萨塞克斯大学数学和物理系主任 David Axon，他也是RIT的研究讲座教授。
For more information, contact
更多信息，请联系：
Daniel Batcheldor at (321) 674-7717 or dbatcheldor@fit.edu
Andrew Robinson at (585) 475-2726 or axrsps@rit.edu.
A Web site with more information is also available: http://quasar.astro.fit.edu/~perlman/blackhole/.
更多的信息可访问上面的链接
The research team’s paper is available here: http://arXiv.org/abs/1005.2173.
研究报告可从上面的链接下载（我又不能……） |
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