7,465 research outputs found
The Dark Z' Portal: Direct, Indirect and Collider Searches
We perform a detailed study of the dark Z' portal using a generic
parametrization of the Z'-quarks couplings, both for light (8-15)GeV and heavy
(130-1000)GeV dark matter scenarios. We present a comprehensive study of the
collider phenomenology including jet clustering, hadronization, and detector
artifacts, which allows us to derive accurate bounds from the search for new
resonances in dijet events and from mono-jet events in the LHC 7TeV, LHC 8TeV,
and Tevatron 1.96 TeV data. We also compute the dark matter relic abundance,
the relevant scattering cross sections and pair-annihilation spectrum, and
compare our results with the current PLANCK, Fermi-LAT and XENON100/LUX bounds.
Lastly, we highlight the importance of complementary searches for dark matter,
and outline the excluded versus still viable parameter space regions of the
dark Z' portal.Comment: 29 pages, 21 figure
The 750 GeV -cion: Where else should we look for it?
The resonance at GeV in the diphoton channel observed by ATLAS
and CMS, if it holds up, is almost certainly the ()cion of a larger dynasty
in a UV completion that may very well be connected to the hierarchy problem. At
this stage, however, an effective field theory framework provides a useful way
to parametrize searches for this resonance in other channels. Assuming that the
excess is due to a new scalar or pseudoscalar boson, we study associated
production of ("-strahlung") at the LHC and propose searches in several
clean channels like , \gamma\gamma\ell\eslash and
\ell\ell\ell\gamma\eslash to probe dimension-5 operators coupling to
Standard Model gauge bosons. We consider a range of widths for , from 5 GeV
to 45 GeV, and find that the three channels probe complementary regions of
parameter space and the suppression scale . The finding of most
immediate relevance is that with 3 fb, the LHC might already reveal new
excesses in the channel and a 5(3) discovery
may already be possible after collecting 65(25) fb of data with
\ell\ell\ell\gamma\eslash events if the scale of the new physics is within
9 TeV for couplings respecting 8 TeV LHC bounds and compatible with the
observed excess in diphotons for a wide resonance as suggested by the ATLAS
Collaboration. Beyond the EFT parametrization, we found realizations of models
with heavy vector-like quarks and leptons which can simultaneously fit the
diphoton excess and be discovered in the channels proposed here.Comment: 11 pages, 2 tables, 5 figures. References and comments added. Version
accepted for publication in Physics Letters
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