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2013:groups:np:effectivedm

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Dark matter searches at the LHC

Projects:

Recommendations for presenting LHC effective DM results

Goal - create a short document recommending:

1) How to present effective direct detection cross section limits from monojet (or mono-anything) searches while making clear the limits of the effective theory and the role of a light mediator mass.

2) What is the most useful set of operators to present results for, and how can the results be presented to be most useful for recasting to a full model.

Interested people:

Name e-mail
Kiel Howe howek@stanford.edu
Brian Shuve bshuve@perimeterinstitute.ca
Gordan Krnjaic gkrnjaic@perimeterinstitute.ca
Andreas Goudelis andreas.goudelis@lapth.cnrs.fr
Csaba Balazs csaba.balazs@monash.edu
Yun Jiang yunjiang@ucdavis.edu
Alex Arbey alexandre.arbey@ens-lyon.fr

Improving sensitivity of monojet-like searches

Goal - determine the best set of cuts to study ISR + MET final states for single insertions of effective Dark Matter operators (for example, the Harnik et. al. razor recast)

Interested people:

Name e-mail
Marija Marjanovic marija.marjanovic@cern.ch

Exploring other signal channels for simplest UV completions of effective operators

Goal - in the region where monojet constraints allow fairly large couplings of mediators, are there other unexplored channels to look in? Possible examples:

  • Dijet resonance
  • Dijet resonance + missing energy
  • t-channnel mediator pair production through light DM exchange
  • Di-top resonance or di-vector-like-quark resonance for gluon operator

Should we tie this in with paired resonances working group?

Interested people:

Name e-mail
Kiel Howe howek@stanford.edu
Brian Shuve bshuve@perimeterinstitute.ca
Andreas Goudelis andreas.goudelis@lapth.cnrs.fr
Aoife Bharucha aoife.bharucha@desy.de
Gordan Krnjaic gkrnjaic@perimeterinstitute.ca

Interpretation of the LHC monojet searches in terms of indirect detection and relic density

Goal - the monojet searches at the LHC are currently reinterpreted (in a simple effective model with one mediator and one DM particle) in terms of dark matter scattering cross-sections with matter, as in direct detection experiments. Can we set also limits on indirect detection (gamma, proton, anti-proton spectra)? And can we deduce a lower limit on the relic density? Additional questions:

  • which effective models are the most strongly constrained?
  • what if more than one mediator/operator is present?
  • which models are interesting?
  • can we reinterpret the DM direct search results in terms of LHC cross-section?

Interested people:

Name e-mail
Alex Arbey alexandre.arbey@ens-lyon.fr
Genevieve Belanger belanger@lapth.cnrs.fr
Andreas Goudelis andreas.goudelis@lapth.cnrs.fr
Nazila Mahmoudi nazila@cern.ch
Sacha Pukhov pukhov@lapth.cnrs.fr



More General Thoughts

Questions:

  • Reference masses for DM on mediator plots (Why 50 and 500? Why not 5 GeV)
  • Experimental limits on more effective operators (including interesting flavor structures?)
  • Is there a convention for plots that makes clear the limited validity of the effective theory?
  • Does anything change for t-channel mediators?
  • What extensions beyond monojet/monophoton searches can set stronger limits on effective operators? E.g. production in association with 3rd generation (e.g. http://xxx.lanl.gov/abs/1303.6638v1), Z/leptons + MET (e.g. http://arxiv.org/abs/1212.3352), …
  • What can shape/variable analyses add to the sensitivity of these searches? (e.g. the Razor analysis in http://arxiv.org/abs/arXiv:1203.1662)

References:

LHC limits:

Effective DM theory:

Mediator production:

Beyond Effective dark matter

  • How can limits easily be translated to models with multiple mediators / multiple effective operators?
  • How can the relevance (or irrelevance) of effective operator limits to full models like SUSY best be expressed?
  • What DM-motivated searches can not be expressed in an effective operators / single mediator picture?

Breit-Wigner cross-section

$\sigma_{LHC}(pp \to \chi \bar{\chi} +X)\sim \left|\frac{g_q g_\chi E}{(s-M_X^2)+iM_X\Gamma_X/2}\right|^2 \sim \frac{1}{\Lambda^4}$
where $E$ is of order the partonic center-of-mass energy.
Two regions to study/search

  • $M_X >> M_\chi, E_{cut}$
  • $M_X \ge M_\chi, E_{cut}$
2013/groups/np/effectivedm.1371662860.txt.gz · Last modified: 2013/06/19 19:27 by nazila.mahmoudi