Day 1419

Wednesday.

1805.10486
First model independent results from DAMA/LIBRA-phase2
Bernabei, et al

The first model independent results obtained by the DAMA/LIBRA-phase2 experiment are presented.  The data have been collected over 6 annual cycles corresponding to a total exposure of 1.13 ton x yr, deep underground at the Gran Sasso National Laboratory (LNGS) of the INFN.  The DAMA/LIBRA-phase2 apparatus, ~250 kg highly radio-pure NaI(TI), profits from a second generation high quantum efficiency photomultipliers and of new electronics with respect to DAMA/LIBRA-phase1.  The improved experimental configuration has also allowed to lower the software energy threshold.  New data analysis strategies are presented.  The DAMA/LIBRA-phase2 data confirm the evidence of a signal that meets all the requirements of the model independent DM annual modulation signature, at 9.5 sigma C.L. in the energy region (1-6) keV.  In the energy region between 2 and 6 keV, where data are also available from DAMA/NaI and DAMA/LIBRA-phase1 (exposure 1.33 ton x yr, collected over 14 annual cycles), the achieved C.L. for the full exposure (2.46 ton x yr) is 12.9 sigma; the modulation amplitude of the single-hit scintillation events is: (0.0103±0.0008) cpd/kg/keV, the measured phase is (145 ±5) days and the measured period is (0.999±0.001) yr, all these values are well in agreement with those expected for DM particles.  No systematics or side reaction able to mimic the exploited DM signature (i.e. to account for the whole measured modulation amplitude and to simultaneously satisfy all the requirements of the signature), has been found or suggested by anyone throughout some decades thus far.


1805.11525
Wide-area tomography of CMB lensing and the growth of cosmological density fluctuations
Peacock, Bilicki

Describe a tomographic dissection of the Planck CMB lensing data, cross-correlating this map with galaxies in different ranges of photometric z.  Use the nearly all-sky 2MPZ and WISExSCOS catalogues for z<0.35, extending to z<0.6 using SDSS.  Describe checks for consistency between the different datasets, and perform a test for possible leakage of thermal SZ signal into the cross-correlation measurements.  The amplitude of the X-correlation allows estimate of the evolution of density fluctuations as a function of z, thus providing a test of theories of modified gravity.  Assuming the common parameterization for the logarithmic growth rate, f_g=Omega_m(z)^gamma, infer gamma=0.77±0.18 when Omega_m is fixed using external data.  Thus CMB lensing tomography is currently consistent with Einstein gravity, where gamma=0.55 is expected.  Discuss how such constraints may be expected to improve with future data.