mini-streams by stars
نویسندگان
چکیده
The promising neutralino dark matter particles generically condense into numerous earth-mass dark halos with smaller substructures suppressed by free streaming[1]. The recent Letter to Nature[2] claims that these 0.01pc-sized dense halos emerged at redshifts 60–26 are rarely destructed inside galaxies, hence the nearest halos at about 0.1pc from Earth are bright in annihilation-powered gamma-rays, but are inaccessible to direct detections. However, most mini-halos reaching solar neighbourhood should experience strong impulses by individual stars in the Galactic disk and bulge, and have been torn into pc-long tidal streams over a Hubble time with only modest overdensity, reducing indirect annihilation signals. Sweeping across the solar system
منابع مشابه
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