在銀河系中心發現十二個黑洞

(本文翻譯自：Dozen black holes found at galactic centre)

研究人員表示，在我們的銀河系中心可能存在12個黑洞。

A dozen black holes may lie at the centre of our galaxy, the Milky Way, researchers have said.

一項新的分析為幾十年來「星系中心的超大質量黑洞被許多較小的黑洞所包圍」的預測提供了支持。

A new analysis provides support for a decadesold prediction that "supermassive" black holes at the centres of galaxies are surrounded by many smaller ones.

然而，在之前對銀河系中心最近的超大質量黑洞的位置的搜索中卻沒有找到任何證據。

However, previous searches of the Milky Ways centre, where the nearest supermassive black hole is located, have found little evidence for this.

來自紐約哥倫比亞大學的Charles Hailey和他的同事們利用NASA的錢德拉x射線望遠鏡的檔案數據而得出結論。

Charles Hailey from Columbia University in New York and colleagues used archival data from Nasas Chandra X ray telescope to come to their conclusions.

他們報告發現了十二個不活躍且低質量的「雙星系統」，而其中的一顆恆星圍繞著一個看不見的伴星——黑洞。

They report the discovery of a dozen inactive and low mass "binary systems", in which a star orbits an unseen companion - the black hole.

銀河系中心的超大質量黑洞，被稱為射手座A *（Sgr A *），被氣體和塵埃暈環繞，為大質量恆星的誕生提供了完美的溫床。這些恆星生存，死亡，並可能在那裡變成黑洞。

The supermassive black hole at the centre of the Milky Way, known as Sagittarius A* (Sgr A*), is surrounded by a halo of gas and dust that provides the perfect breeding ground for the birth of massive stars. These stars live, die and could turn into black

holes there.

此外，暈圈外的黑洞被認為是在Sgr A *的影響下墜落的，因為它們失去了能量，導致它們被拉到附近，在那裡它們被Sgr A *的力量俘虜。

In addition, black holes from outside the halo are believed to fall under the influence of Sgr A* as they lose their energy, causing them to be pulled into its vicinity, where

they are held captive by its force.

其中一些綁定 - 或「配合」-通過恆星，形成二元系統。

Some of these bind - or "mate" - to passing stars, forming binary systems.

之前探測黑洞數量的嘗試主要都是在尋找黑洞雙星有時發出的明亮的x射線。

Previous attempts to detect this population of black holes have looked for the bright bursts of X-rays that are sometimes emitted by black hole binaries.

微弱而穩定

Faint and steady

Hailey教授稱：」銀河系中心距離地球太遠，以至於這種爆發強度和亮度只足以讓我們每隔100到1000年觀測到一次。

"The galactic centre is so far away from Earth that those bursts are only strong and bright enough to see about once every 100 to 1,000 years," said Prof Hailey.

相反，哥倫比亞大學天體物理學家和他的同事們決定尋找當這些二元系統處於非活躍狀態時發射的更暗淡、但更穩定的X射線。

Instead, the Columbia University astrophysicist and his colleagues decided to look for the fainter but steadier X-rays emitted when these binaries are in an inactive state.

「孤立的、未統一的黑洞只是展現出黑色-他們只是待在那，」海利教授說。

"Isolated, unmated black holes are just black - they dont do anything," said Prof Hailey.

「但是，當黑洞與低質量恆星結合時，會發出X射線陣，這些射線陣雖然較弱，但是連續的並且可檢測。」

"But when black holes mate with a low mass star, the marriage emits X-ray bursts that are weaker, but consistent and detectable."

在錢德拉數據中尋找低質量黑洞雙星的x射線信號，在Sgr A*的3光年範圍內發現了12個。

A search for the X-ray signatures of low-mass black hole binaries in the Chandra

data turned up 12 within three light-years of Sgr A*.

根據這些雙星的性質和分布推斷，研究小組估計在Sgr A*周圍可能有300-500個低質量的雙星和10000個單獨的低質量黑洞。

By extrapolating fro the properties and distribution of these binaries, the team estimates that there may be 300-500 low-mass binaries and 10,000 isolated low-mass black holes surrounding Sgr A*.

海利教授表示，這一發現「證實了一個主要理論」，並補充道:「它將極大地推進引力波研究，因為如果我們知道一個典型星系中心的黑洞數量，我們將能更好地預測有多少引力波事件可能與黑洞有關。」

Prof Hailey said the finding "confirms a major theory", adding: "It is going to significantly advance gravitational wave research because knowing the number of

black holes in the centre of a typical galaxy can help in better predicting how many gravitational wave events may be associated with them."

引力波是時空結構中的波紋。它們被阿爾伯特·愛因斯坦的廣義相對論預言，並在2015年被Ligo實驗發現。產生這些漣漪的一種方式是通過單獨的黑洞的碰撞。

Gravitational waves are ripples in the fabric of space-time. They were predicted by Albert Einsteins general theory of relativity and detected by the Ligo experiment in 2015. One way these ripples arise is through the collision of separate black holes.

翻譯： @浪流海北@JellyJelly@unclethree39

公眾號:BNN資訊圈（bnn_news)

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