Les Houches

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Responsibles: Grégory Moreau [TH](moreau@th.u-psud.fr), Jose Miguel No [TH] (josemiguel.no@uam.es), Susan Gascon-Shotkin [EXP](smgascon@mail.cern.ch)

People involved (TBC!!): Sophie Williamson (swilliamson@lpthe.jussieu.fr), Aoife Bharucha (aoife.bharucha@cpt.univ-mrs.fr), Antoine Lesauvage (antoine.baptiste.lesauvage@cern.ch), Jérémie Quevillon (jeremie.quevillon@lpsc.in2p3.fr), Shilpi Jain(shilpi.jain@cern.ch), Shankha Banerjee (banerjeeshankha@gmail.com), Biplob Bhattacherjee(bbhattacherjee@gmail.com), Nishita Desai (nishita.desai@umontpellier.fr), Jon Butterworth (J.Butterworth@ucl.ac.uk), Natascia Vignaroli (vignaroli@pd.infn.it), Kohsaku Tobioka (ktobioka@fsu.edu), José Zurita (jose.zurita@kit.edu), Giacomo Polesello (giacomo.polesello@cern.ch).

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Exotic Higgs decays into h → Z $\phi$

Reference to look for general motivation on exotic Higgs decays, possible models, etc, as well as for information on theoretical work and experimental analylis (as of 2013!): Review/compendium work on exotic Higgs decays from Curtin, Gori, Shelton, Strassler et al 1312.4992.

, $\phi$ → $\gamma\gamma$. Preliminary study from Bauer, Neubert, Thamm 1708.00443 (see also 1704.08207). They put limits on very light ALPs (m_a < 47 MeV) from constraints on h → Z $\gamma$, since for m_a < 47 MeV the two photons from the ALP decay are very collimated and seen as one in the detector. For not-so-light ALPs, they compute just number of signal events for gg → h → Z $\phi$, and assume limits for 100 events at LHC (some more discussion in seminvisible).

For $m_\phi > 35$ GeV:

$h \to Z^* \phi$, $Z^* \to \mu\mu$ [names: SG, AL, JN, GM]

$h^* \to Z \phi$ [UFO files from effective ggh coupling for kinematics and rescale rate with ggF cross section?]

For 47MeV < $m_\phi < 35$ GeV:

$h \to Z \phi$, $Z \to \mu\mu$, $\phi \to \gamma\gamma$ [names: SG, AL, JN, GM, KT]

$h \to Z \phi$, $Z \to \mu\mu$, $\phi \to \mu\mu$ recasted from existing analysis of $h \to \phi \phi$, $\phi \to \mu\mu$ [names: KT]