Pion and Dark Matter

1. Jul 23, 2015

RyanH42

2. Jul 23, 2015

Dr. Courtney

I can't think of any reason to quickly dismiss the idea, and neither could the peer-reviewers or editors at PRL.

Now, how can it be tested ...

3. Jul 23, 2015

Orodruin

Staff Emeritus
Note that it does not say that dark matter is a pion. It is saying it is like a pion under some new gauge symmetry. Pions decay way to fast to be dark matter.

4. Jul 23, 2015

marcus

For reference, here is their article
http://arxiv.org/abs/1411.3727
The SIMPlest Miracle
Yonit Hochberg, Eric Kuflik, Hitoshi Murayama, Tomer Volansky, Jay G. Wacker
(Submitted on 13 Nov 2014)
It has recently been proposed that dark matter could be a thermal relic of 3-to-2 scatterings in a strongly coupled hidden sector. We present explicit classes of strongly coupled gauge theories that admit this behavior. These are QCD-like theories of dynamical chiral symmetry breaking, where the pions play the role of dark matter. The number-changing 3-to-2 process, which sets the dark matter relic abundance, arises from the Wess-Zumino-Witten term. The theories give an explicit relationship between the 3-to-2 annihilation rate and the 2-to-2 self-scattering rate, which alters predictions for structure formation. This is a simple calculable realization of the strongly-interacting-massive-particle (SIMP) mechanism.
7 pages, 2 figures published PRL(2015) with the title changed to "Model for Thermal Relic Dark Matter of Strongly Interacting Massive Particles"
http://inspirehep.net/record/1328090?ln=en

an earlier paper:
http://arxiv.org/abs/1402.5143
The SIMP Miracle
Yonit Hochberg, Eric Kuflik, Tomer Volansky, Jay G. Wacker
(Submitted on 20 Feb 2014 (v1), last revised 28 Oct 2014 (this version, v2))
We present a new paradigm for achieving thermal relic dark matter. The mechanism arises when a nearly secluded dark sector is thermalized with the Standard Model after reheating. The freezeout process is a number-changing 3->2 annihilation of strongly-interacting-massive-particles (SIMPs) in the dark sector, and points to sub-GeV dark matter. The couplings to the visible sector, necessary for maintaining thermal equilibrium with the Standard Model, imply measurable signals that will allow coverage of a significant part of the parameter space with future indirect- and direct-detection experiments and via direct production of dark matter at colliders. Moreover, 3->2 annihilations typically predict sizable 2->2 self-interactions which naturally address the core vs. cusp' and too-big-to-fail' small structure problems.
8 pages, 3 figures; v2: minor updates. Published in PRL(2014) with the title "Mechanism for Thermal Relic Dark Matter of Strongly Interacting Massive Particles."
http://inspirehep.net/search?p=find+eprint+1402.5143
32 citations
I'm not sure but think I've seen one or two papers that seen to constrain this idea using observational evidence that DM particles are not strongly self-interactive. Not sure, but it would be worth a look.

Yes here is something:
http://cerncourier.com/cws/article/cern/60874
but it could be wrong. DM could be more self-interactive than those people found.
another:
http://inspirehep.net/record/1381768
another:
http://arxiv.org/abs/1503.07675
(puts a limit on the self-interaction cross-section)

Last edited: Jul 23, 2015
5. Jul 24, 2015

Orodruin

Staff Emeritus
One of them being this:

Not the SIMPlest Miracle
Martin Hansen, Kasper Langaeble, Francesco Sannino
(Submitted on 6 Jul 2015)
We investigate the phenomenological viability of a recently proposed class of composite dark matter models where the relic density is determined by 3 to 2 number-changing processes in the dark sector. Here the pions of the strongly interacting field theory constitute the dark matter particles. By performing a consistent next-to-leading and next-to-next-to-leading order chiral perturbative investigation we demonstrate that the leading order analysis cannot be used to draw conclusions about the viability of the model. We further show that higher order corrections substantially increase the tension with phenomenological constraints challenging the viability of the simplest realisation of the strongly interacting massive particle (SIMP) paradigm.

6. Jul 24, 2015

marcus

Yes : ^)
I included a link to the Hansen et al "Not the SIMPlest..." paper in my post. It is the second one here---the http://inspirehep.net/record/1381768