DAMA/LIBRA-phase2 in WIMP effective models
  The DAMA/LIBRA collaboration has recently released updated results from their
search for the annual modulation signal expected from Dark Matter (DM)
scattering in their NaI detectors. We have fitted the updated DAMA result for
the modulation amplitudes in terms of a Weakly Interacting Massive Particle
(WIMP) signal, parameterizing the interaction with nuclei in terms of the most
general effective Lagrangian for a WIMP particle spin up to 1/2, systematically
assuming dominance of one of the 14 possible interaction terms, and assuming
for the WIMP velocity distribution a standard Maxwellian. We find that most of
the couplings of the non-relativistic effective Hamiltonian can provide a
better fit compared to the standard Spin Independent interaction case, and with
a reduced fine-tuning of the three parameters (WIMP mass, WIMP-nucleon
effective cross-section and ratio between the WIMP-neutron and the WIMP-proton
couplings). Moreover, effective models for which the cross section depends
explicitly on the WIMP incoming velocity can provide a better fit of the DAMA
data at large values of $m_{\chi}$ compared to the standard
velocity-independent cross-section due to a different phase of the modulation
amplitudes. All the best fit solutions are in tension with exclusion plots of
both XENON1T and PICO60.
