Quark Soup May Cause Cosmic Flashes

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<b>Quark Soup May Cause Cosmic Flashes</b><br /><br />LINK<br /><br />Intense flashes of gamma rays in far-off galaxies might be produced by a bizarre kind of star, consisting of phenomenally dense material in which the particles that make up atomic nuclei have fallen apart.<br /><br />Two astrophysicists have proposed that gamma-ray (-ray) bursts, whose origins have foxed astronomers for decades, might be the signatures of elusive 'quark stars'. Scientists have speculated that these stars might exist, but have never seen convincing evidence for them.<br /><br />Bohdan Paczyski of Princeton University in New Jersey admits that the idea that he and Pawel Haensel of the Copernicus Astronomical Centre in Warsaw, Poland, have put forward is still theoretical, and must be tested with more g-ray observations.<br /><br />But within days of posting their paper on the arXiv preprint server1, the researchers were given good reason to believe that they are on to something. Davide Lazzati of the University of Colorado at Boulder contacted Paczyski to say that the quark-star hypothesis might explain some puzzling observations made by the Burst and Transient Source Experiment on NASA's Compton Gamma-Ray Observatory, which was launched in 1991.<br /><br />Lazzati noticed that several of the g-ray bursts seemed to be preceded, a few seconds or minutes earlier, by much weaker pulses of -rays2. "That was a puzzle," says Paczyski. But an explanation for these precursory flashes "comes naturally out of our model", he says. "It's very exciting."<br /><br />Super theory<br /><br />Astronomers generally believe that g-ray bursts are produced by supernovae: stars that have run low on fuel and do not emit enough energy to prevent them from collapsing under their own gravity.<br /><br />The collapse heats up the star and generates a 'rebound', in which the star's outer layers get blown off in a massive explosion, while the i