反物质云由于其自身发射的伽玛射线而显现出来，当单个的反物质粒子遇到它们正常物质的对应体（这里是正电子遇到电子）彼此互相消灭了对方。

The cloud shows up because of the gamma rays it emits when individual particles of antimatter, in this case positrons, encounter electrons, their normal matter counterpart, and annihilate one another.

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