this post was submitted on 26 Nov 2025
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[–] AnAnonymousApe@lemmy.ml 24 points 2 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.

[–] sundray@lemmus.org 4 points 2 months ago

~~Big~~ Massive, if true!

[–] magiccupcake@lemmy.world 0 points 2 months ago

Direct observation ≠ direct detection

[–] alekwithak@lemmy.world 18 points 2 months ago (2 children)
[–] Evil_Shrubbery@thelemmy.club 18 points 2 months ago* (last edited 2 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.

[–] Dimand@aussie.zone 12 points 2 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.

[–] l_isqof@lemmy.world 9 points 2 months ago

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

[–] wabafee@lemmy.world 7 points 2 months ago* (last edited 2 months ago) (1 children)

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

[–] sundray@lemmus.org 5 points 2 months ago

We know about dark matter from its attraction. In contrast, what you've discovered sounds repulsive.

[–] BlameTheAntifa@lemmy.world 6 points 2 months ago (1 children)

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

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

[–] clay_pidgin@sh.itjust.works 3 points 2 months ago

It was very good. Joseph Mallozzi posted the original ending that he had planned. https://josephmallozzi.com/2020/07/25/that-original-dark-matter-ending-dark-timeline-edition/

[–] Oppopity@lemmy.ml 3 points 2 months ago (3 children)

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

[–] Naz@sh.itjust.works 8 points 2 months ago (1 children)

Inside the dog it is too dark to see

[–] Klear@quokk.au 3 points 2 months ago

That's a good quote.

[–] Grimy@lemmy.world 5 points 2 months ago

Really really really dark grey matter

[–] sundray@lemmus.org 3 points 2 months ago

They plan to rename it "Shy Matter."