Warm dark matter and light sterile neutrinos

[marcus]

It could be useful to group some references for this:
http://arxiv.org/pdf/1204.5379v1.pdf (Light Sterile Neutrinos: A White Paper)

http://arxiv.org/abs/arXiv:1311.0282 (Sterile neutrino dark matter bounds from galaxies of the Local Group)

I'd like some more references. Please share any good link you have.

 

[marcus]

Here's another paper that I happened to find, that might be relevant. It's an easy-to-read review of recent progress. Phenomenology means coming up with with ways of testing, detecting, observing the effects (if that kind of neutrino exists).

http://arxiv.org/abs/arXiv:1303.6912
The Phenomenology of Right Handed Neutrinos
Marco Drewes
(Submitted on 27 Mar 2013)
Neutrinos are the only particles in the Standard Model of particle physics that have only been observed with left handed chirality to date. If right handed neutrinos exist, they could be responsible for several phenomena that have no explanation within the Standard Model, including neutrino oscillations, the baryon asymmetry of the universe, dark matter and dark radiation. After a pedagogical introduction, we review recent progress in the phenomenology of right handed neutrinos. We in particular discuss the mass ranges suggested by hints for neutrino oscillation anomalies and dark radiation (eV), sterile neutrino dark matter scenarios (keV) and experimentally testable theories of baryogenesis (GeV to TeV). We summarize constraints from theoretical considerations, laboratory experiments, astrophysics and cosmology for each of these.
Comments: Invited review for the International Journal of Modern Physics E.

There is a GAP in the Standard Model catalog of particles because all the other particles except neutrinos are known to exist in two versions (called right and left handed) but righthand neutrinos have not been seen yet.

Also there's evidence that DM might be WARM---that is moving around just fast enough on average to explain why it hasn't collected around dwarf galaxies as much as it would have if it were slow-moving i.e. "cold". That is, there are independent reasons to suspect that the LambdaCDM cosmic model should be traded in for the LambdaWDM model.

But that just HAPPENS TO FIT the RH neutrino idea because if DM were made of RH neutrinos then it would be warm. DM particles would be moving around faster on average than if they were a different more massive type. So the DM = RH neutrino idea gets support from two directions.

The Standard particle menu has a RH neutrino gap, and they'd be suitable DM particles if they exist.
The observed DM clouds seem made of particles that move on average faster than we thought, and that is how RH neutrinos would be if they constituted the DM clouds.

So this Marco Drewes 2013 paper is a good one and pertinent to topic.
Also Marco has coauthored with Mikhail Shaposhnikov who is a prominent authority on minimalist extensions of the Standard menu, especially νMSM, and who predicted the Higgs mass accurately two years before it was detected.

 

[Chronos]

I agree the sterile neutrino remains a viable dark matter candidate. It is an attractive solution to a number of puzzling cosmological mysteries, including matter-antimatter asymmetry and pulsar kicks [re: http://www.universetoday.com/8057/is-dark-matter-made-up-of-sterile-neutrinos/] . But, I find it hard to believe it is in exclusive company. DM could consist of a virtual a zoo of other dark particles in various proportions. A mix of warm and cold DM particles could resolve the tension in observational constraints on any single class of DM particles.

 

[marcus]

Sure! There are a bunch of proposed candidates, even including clouds of tiny primordial black holes left in the wake of the "big bang". I'm just interested with this thread in gathering recent source material about the RH neutrino possibility.

I was glad to see your comment and since you know some of the specifics about this possible DM constituent, do you have any pertinent links to recent articles?

 

[marcus]

Here's an Inspire search. Some of the papers that come up here offer evidence that DISfavors the hypothesis that sterile noos comprise DM. You might like to sample the titles and check out some of the abstracts.
http://inspirehep.net/search?ln=en&...&action_search=Search&sf=&so=d&rm=&rg=25&sc=0
If you find anything interesting, pro or con, please post it!

Here's a similar search, but calling for both "sterile neutrino" AND "dark matter":
http://inspirehep.net/search?ln=en&...search=Search&sf=&so=d&rm=citation&rg=25&sc=0

Both searches are restricted to papers that appeared this year, so as to get an idea of the most recent thinking on the subject.

 

[Chronos]

Yes, I am aware of the evidence disfavoring sterile neutrinos as DM. But, they only disfavor it as being solely responsible for DM. There are numerous papers favoring sterile neutrinos as DM. One I would like to specifically mention is http://arxiv.org/abs/1204.3902, Sterile Neutrinos as the Origin of Dark and Baryonic Matter, by Canetti and Shaposhnikov - who have written other interesting papers on this subject. My big gripe is I think studies to date have neglected to consider a mix of DM particles as a possibility. I think that is roughly equivalent to assuming all baryonic matter consists of protons. I suspect that would probably also lead to some discrepancies with observational evidence.

 

[marcus]

... There are numerous papers favoring sterile neutrinos as DM. One I would like to specifically mention is http://arxiv.org/abs/1204.3902, Sterile Neutrinos as the Origin of Dark and Baryonic Matter,...

Yes! That one is fairly recent and Marco Drewes (cited earlier) was one of the authors. It's worth including the abstract here!
http://arxiv.org/abs/1204.3902
Sterile Neutrinos as the Origin of Dark and Baryonic Matter
Laurent Canetti, Marco Drewes, Mikhail Shaposhnikov
(Submitted on 17 Apr 2012)
We demonstrate for the first time that three sterile neutrinos alone can simultaneously explain neutrino oscillations, the observed dark matter and the baryon asymmetry of the Universe without new physics above the Fermi scale. The key new point of our analysis is leptogenesis after sphaleron freeze-out, which leads to resonant dark matter production, evading thus the constraints on sterile neutrino dark matter from structure formation and x-ray searches. We identify the range of sterile neutrino properties that is consistent with all known constraints. We find a domain of parameters where the new particles can be found with present day experimental techniques, using upgrades to existing experimental facilities.
4 pages, 2 figures

This was published in Physical Review Letters in February 2013. I don't know why it took PRL so long to accept and publish the paper--something like 10 months since it was submitted to the journal in April.
http://prl.aps.org/abstract/PRL/v110/i6/e061801

Here's the Inspire link. http://inspirehep.net/record/1111187?ln=en
The paper already has 33 cites.

 

[marcus]

Here are Shaposhnikov's slides from a June 2013 conference, look at slide #21 (and surrounding ones). This is a brief, cogent, graphic presentation of the idea.
https://www.kvi.nl/ssp2012/material/104-shaposhnikov/slides/104-1-ssp2012_shaposhnikov.pdf

Shaposhnikov's talk was based in part on this paper which is not on arxiv, but was listed as included in the proceedings of the conference
http://inspirehep.net/record/1242166?ln=en
The ν MSM and muon to electron conversion experiments
Laurent Canetti, Mikhail Shaposhnikov (IPT, Lausanne)
Hyperfine Interact. 214 (2013) 5-11
DOI: 10.1007/s10751-013-0796-7
Conference: C12-06-18 Proceedings
Abstract
We review briefly the different constraints on the three right-handed neutrinos of the νMSM, an extension of the Standard Model that can explain baryon asymmetry, dark matter and neutrino masses. We include in the discussion the proposed experiments on muon to electron conversion Mu2e (Carey et al., Mu2e Collaboration, 2012), COMET and PRISM (Hungerford, COMET Collaboration, AIP Conf Proc 1182:694, 2009; Cui et al., COMET Collaboration, 2012). We find that the expected sensitivity of these experiments is weaker by about two orders of magnitude than the constraints coming from successful baryogenesis.