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[–] 10 points 11 months ago

Huh, actually kinda amazing, and def a bit more than the "typically bs" title hinted.

Fifteen years of the Fermi Large Area Telescope (LAT) data in the halo region of the Milky Way (MW) are analyzed to search for gamma rays from dark matter annihilation. . . . A statistically significant halo-like excess is found with a spectral peak around 20 GeV, while its flux is consistent with zero below 2 GeV and above 200 GeV. Examination of the fit residual maps indicates that a spherically symmetric halo component fits the map data well. The radial profile agrees with annihilation by the smooth NFW density profile, and may be slightly shallower than this, especially in the central region. . . . The halo excess spectrum can be fitted by annihilation with a particle mass mχ ∼ 0.5–0.8 TeV and cross section 〈συ〉 ∼ (5–8) × 10-25 cm3 s-1 for the bb̅ channel. This cross section is larger than the upper limits from dwarf galaxies and the canonical thermal relic value, but considering various uncertainties, especially the density profile of the MW halo, the dark matter interpretation of the 20 GeV “Fermi halo” remains feasible. The prospects for verification through future observations are briefly discussed.

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  • [–] 9 points 11 months ago*

    Extra high energy particles too. So next time we get hit by secondary particles from a cosmic ray we know what's to blame. On the other hand the planet might not all be here without the extra gravity from dark matter so it's still all good. Radiation induced Cancer is horrible but having a decent sized planet is a definite plus

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  • [–] 7 points 11 months ago (4 children)
  • [–] 8 points 11 months ago (3 children)

    No! You CAN'T see it. That's the whole point!

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  • [–] 29 points 11 months ago (7 children)

    Before even following the link... #doubt

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  • [–] 41 points 11 months ago* (2 children)

    They’re seeing gamma rays from suspected dark matter collisions—that’s actually more substantially accurate than I was expecting.

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  • [–] 23 points 11 months ago

    To clarify, that's the collision of 2 dark matter particles.
    Not the collision of a dark matter particle and something else.

    researchers report that they have detected the invisible scaffolding based on gamma rays that result from the collision and resulting annihilation of two dark matter particles.

    So, that's 2 particles of this unobservable (or, difficult to observe) matter interacting with eachother in an observable way.
    Very cool

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  • [–] 5 points 11 months ago (2 children)

    they shpuld have put the "indirectly" in the headline, but then they would be decent. can't have that

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  • [–] 8 points 11 months ago* (last edited 11 months ago)

    but then they would be decent

    Lmao, what? No, if they put "indirectly" in the headline, then they'd be just as decent but actively wrong about it being the first time. We've detected dark matter in plenty of indirect ways, from the Bullet Cluster to the angular velocity of galaxies. I don't think you understand how often particle physicists observe things based on predicted properties (such as "this decays into that") rather than something we see "directly".

    Dark matter is dark matter because it only interacts gravitationally with "normal" matter and energy, and we've already observed that gravitational interaction. So what's your standard for not qualifying a dark matter observation as "indirect"? Did you want two dark matter black holes colliding? Did you want the scientists to magically change how electromagnetism works?

    It's fine if you don't think this is an observation of dark matter at all, but "indirect" is needlessly splitting hairs in this field. You can read the journal article – at least the abstract – and see what the evidence is.

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  • [–] 7 points 11 months ago (1 child)

    Scientists are SLAMMED by dark matter sightings.

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  • 17 comments in c/science@lemmy.world view that post
    [–] 24 points 11 months ago (2 children)

    I'm guessing this will turn out to be wrong, like the other times they apparently detected it. Would be very cool if true though.

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  • [–] 12 points 11 months ago

    https://arxiv.org/abs/2507.07209

    I can't stand these popular science articles that just cherry pick phrases from a paper. tl;dr it's a very promising result but more observation of other galaxies or other mass consistent observations is needed before we should believe this.

    However, the signal from the MW halo alone does not constitute the definitive proof of dark matter annihilation. Detection of annihilation signals from other objects or regions with consistent WIMP parameters will be crucial for the final confirmation. Gamma-ray observations of dwarf galaxies in the MW halo are fascinating from this perspective.

    I would say the most exciting part is this gives us a mass range to optimise the search with earth based detectors. Start looking for 0.5-0.8 TeV masses.

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  • [–] 19 points 11 months ago (2 children)
  • [–] 18 points 11 months ago*

    Fifteen years of the Fermi Large Area Telescope (LAT) data in the halo region of the Milky Way (MW) are analyzed to search for gamma rays from dark matter annihilation. . . . A statistically significant halo-like excess is found with a spectral peak around 20 GeV, while its flux is consistent with zero below 2 GeV and above 200 GeV. Examination of the fit residual maps indicates that a spherically symmetric halo component fits the map data well. The radial profile agrees with annihilation by the smooth NFW density profile, and may be slightly shallower than this, especially in the central region. . . . The halo excess spectrum can be fitted by annihilation with a particle mass mχ ∼ 0.5–0.8 TeV and cross section 〈συ〉 ∼ (5–8) × 10-25 cm3 s-1 for the bb̅ channel. This cross section is larger than the upper limits from dwarf galaxies and the canonical thermal relic value, but considering various uncertainties, especially the density profile of the MW halo, the dark matter interpretation of the 20 GeV “Fermi halo” remains feasible. The prospects for verification through future observations are briefly discussed.

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  • [–] 6 points 11 months ago (1 child)

    The show is only a year old, and it was genuinely great.

    We’re not talking about the TV series, are we?

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  • [–] 10 points 11 months ago

    I thought they had 30 days to release the files...

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  • [–] 7 points 11 months ago* (1 child)

    I have seen dark matter from time to time especially after eating lots of red meat.

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  • [–] 4 points 11 months ago (4 children)

    If you can see it it's no longer dark matter, just matter.

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