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Giant simulation could help solve “dark matter” mystery

Nov. 5, 2008
Courtesy Durham University
and World Science staff

A gi­ant com­put­er sim­ula­t­ion could help br­ing a suc­cess­ful end to the search for a mys­te­ri­ous sub­stance which makes up most of the Uni­verse, ac­cord­ing to new re­search.

As­tro­no­mers be­lieve the en­ig­mat­ic “dark mat­ter” ac­counts for 85 per cent of the ma­te­ri­al in the uni­verse. But the stuff has re­mained in­vis­i­ble, its make­up un­known, since sci­en­tists in­ferred its ex­ist­ence from its gravita­t­ional ef­fects more than 75 years ago.

Frame from a simu­la­tion of a Milky-Way sized galaxy halo (cour­tesy Vir­go Con­sor­tium).


Now a team of sci­en­tists has used a mas­sive com­put­er sim­ula­t­ion show­ing the ev­o­lu­tion of a gal­axy like the Milky Way to “see” high-en­er­gy ra­di­a­t­ion re­leased by dark mat­ter. 

They say their find­ings, pub­lished in the re­search jour­nal Na­ture Nov. 6, could help NA­SA’s Fer­mi Tel­e­scope in its search for the dark mat­ter and open a new chap­ter in our un­der­stand­ing of the uni­verse.

“The search for dark mat­ter has dom­i­nat­ed cos­mol­o­gy for many dec­ades. It may soon come to an end,” said cos­molo­g­ist Car­los Frenk of Dur­ham Uni­ver­s­ity, U.K., a mem­ber of the re­search team, which al­so in­volves sci­en­tists from Ger­many, The Neth­er­lands and the Un­ited States.

The group, known as the Vir­go Con­sor­ti­um, stud­ied dark mat­ter ha­los, blob-like struc­tures that sur­round ga­lax­ies and con­tain a tril­lion times the mass of the Sun. 

The team’s sim­ula­t­ions, called The Aquar­i­us Proj­ect, showed how the gal­ax­y’s ha­lo would have been ex­pected to grow through a se­ries of vi­o­lent col­li­sions and merg­ers be­tween much smaller clumps of dark mat­ter ear­li­er in cos­mic his­to­ry.

The group found that gamma-rays, a form of en­er­get­ic radia­t­ion, pro­duced when par­t­i­cles col­lide in ar­eas of high dark mat­ter con­centra­t­ion should be most de­tect­a­ble near the Sun in the gen­er­al di­rec­tion of the gal­ax­y’s cen­tre. They sug­gest the Fer­mi Tel­e­scope should search in this part of the gal­axy where they pre­dict gamma-rays from dark mat­ter should glow in “a smoothly var­y­ing and char­ac­ter­is­tic pat­tern.”

If Fer­mi does de­tect the pre­dicted emis­sion from the Milky Way’s smooth in­ner ha­lo, the Vir­go team be­lieves it might be able to see oth­er­wise in­vis­i­ble clumps of dark mat­ter ly­ing very close to the Sun.


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A giant computer simulation could help bring a successful end to the search for a mysterious substance which makes up most of the Universe, according to new research. Astronomers believe the enigmatic “dark matter” accounts for 85 per cent of the material in the universe. But the stuff has remained invisible, its makeup unknown, since scientists inferred its existence from its gravitational effects more than 75 years ago. Now a team of scientists has used a massive computer simulation showing the evolution of a galaxy like the Milky Way to “see” high-energy radiation released by dark matter. They say their findings, published in the research journal Nov. 6, could help NASA’s Fermi Telescope in its search for the dark matter and open a new chapter in our understanding of the Universe. “The search for dark matter has dominated cosmology for many decades. It may soon come to an end,” said cosmologist Carlos Frenk of Durham University, U.K., a member of the research team, which also involves scientists from Germany, The Netherlands and the United States. The group, known as the Virgo Consortium, studied dark matter halos, blob-like structures that surround galaxies and contain a trillion times the mass of the Sun. The team’s simulations, called The Aquarius Project, showed how the galaxy’s halo would have been expected to grow through a series of violent collisions and mergers between much smaller clumps of dark matter earlier in cosmic history. The group found that gamma-rays, a form of energetic radiation, produced when particles collide in areas of high dark matter concentration should be most detectable near the Sun in the general direction of the galaxy’s centre. They suggest the Fermi Telescope should search in this part of the galaxy where they predict that gamma-rays from dark matter should glow in “a smoothly varying and characteristic pattern”. If Fermi does detect the predicted emission from the Milky Way’s smooth inner halo, the Virgo team believes it might be able to see otherwise invisible clumps of dark matter lying very close to the Sun.