Hunting for dark quarks

August 31, 2018 by Ana Lopes, CERN
A proton–proton collision event with two emerging-jet candidates. Credit: CMS/CERN

Quarks are the smallest particles that we know of. In fact, according to the Standard Model of particle physics, which describes all known particles and their interactions, quarks should be infinitely small. If that's not mind-boggling enough, enter dark quarks – hypothetical particles that have been proposed to explain dark matter, an invisible form of matter that fills the universe and holds the Milky Way and other galaxies together.

In a recent study, the CMS collaboration describes how it has sifted through data from the Large Hadron Collider (LHC) to try and spot dark quarks. Although the search came up empty-handed, it allowed the team to inch closer to the parent from which dark quarks may originate.

One compelling theory extends the Standard Model to explain why the observed mass densities of normal matter and dark are similar. It does so by invoking the existence of dark quarks that interact with ordinary quarks via a particle. If such mediator particles were produced in pairs in a proton–proton collision, each mediator particle of the pair would transform into a normal and a dark quark, both of which would produce a spray, or "jet", of particles called hadrons, composed of quarks or dark quarks. In total, there would be two jets of regular hadrons originating from the collision point, and two "emerging" jets that would emerge a distance away from the collision point because dark hadrons would take some time to decay into visible particles.

In their study, the CMS researchers looked through data from proton– collisions collected at the LHC at an energy of 13 TeV to search for instances, or "events", in which such mediator particles and associated emerging jets might occur. They used two distinguishing features to identify emerging jets and pick them out from a background of events that are expected to mimic their traits.

The team found no strong evidence for the existence of such emerging jets, but the data allowed them to exclude masses for the hypothetical mediator particle of 400–1250 GeV for dark pions that travel for lengths between 5 and 225 mm before they decay. The results are the first from a dedicated search for such mediator particles and jets.

Explore further: More than the sum of its parts: the ATLAS Experiment looks inside the proton

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fthompson495
1 / 5 (2) Aug 31, 2018
Dark matter is a supersolid that fills 'empty' space, strongly interacts with ordinary matter and is displaced by ordinary matter. What is referred to geometrically as curved spacetime physically exists in nature as the state of displacement of the supersolid dark matter. The state of displacement of the supersolid dark matter is gravity.

The supersolid dark matter displaced by a galaxy pushes back, causing the stars in the outer arms of the galaxy to orbit the galactic center at the rate in which they do.

Displaced dark matter is curved spacetime.
fthompson495
1 / 5 (3) Aug 31, 2018
If dark quarks fill 'empty' space and interact with ordinary quarks, then the dark quarks displaced by the ordinary quarks the Earth consists of is the quantization of gravity. The displaced dark quarks is the physical manifestation of curved spacetime.
Steelwolf
2.5 / 5 (4) Aug 31, 2018
If they are looking for the "Anti-matter" particle of supposed dark matter decay, it may be such that their facility cannot capture the event because the initial dark particles may not be able to penetrate our normal baryonic material, and even if it does, such dark-antimatter at the quark level may NOT appear as a sudden appearance of known quark-antiquark neutral particle set we already have mapped and might not appear in the form of decay products we already know about. They may may find themselves blocked by the first set of sensors and even reflected in such a way that it never shows in OUR Universe.

I don't know, I can only surmise, but perhaps they might look at overall charge in the areas affected.
DonGateley
not rated yet Sep 01, 2018
@fthompson495: cool ass shit man, keep it coming!
Da Schneib
3 / 5 (2) Sep 03, 2018
Not finding at a high sigma is as significant as finding.
Benni
3 / 5 (2) Sep 03, 2018
There is no such thing as INFINITELY SMALL. But of course were talking Pop-Cosmology Derangement Syndrome here aren't we?

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