Abstract: The production rate and kinematics of photons produced in association with Z bosons are studied using 2 fb(-1) of p (p) over bar collision data collected at the Collider Detector at Fermilab. The cross section for p (p) over bar -> l(+)l(-)gamma + X ( where the leptons l are either muons or electrons with dilepton mass M-ll > 40 GeV/c(2), and where the photon has transverse energy E-T(gamma) > 7 GeV and is well separated from the leptons) is 4.6 +/- 0.2(stat) +/- 0.3 (syst) +/- 0.3 (lum) pb, which is consistent with standard model expectations. We use the photon E-T distribution from Z gamma events where the Z has decayed to mu(+) mu(-) ,e(+) e(-), or nu(+) nu(-) to set limits on anomalous (non standard model) trilinear couplings between photons and Z bosons.

Abstract: We propose an A(4) flavor-symmetric SU(3) circle times SU(2) circle times U(1) seesaw model where lepton number is broken spontaneously. A consistent two-zero texture pattern of neutrino masses and mixing emerges from the interplay of type-I and type-II seesaw contributions, with important phenomenological predictions. We show that, if the Majoron becomes massive, such seesaw scenario provides a viable candidate for decaying dark matter, consistent with cosmic microwave background lifetime constraints that follow from current WMAP observations. We also calculate the subleading one-loop-induced decay into photons which leads to a monoenergetic emission line that may be observed in future x-ray missions such as Xenia.

Abstract: We present an efficient method of reconstructing the parameters of the constrained MSSM from assumed future LHC data, applied both on their own right and in combination with the cosmological determination of the relic dark matter abundance. Focusing on the ATLAS SU3 benchmark point, we demonstrate that our simple Gaussian approximation can recover the values of its parameters remarkably well. We examine two popular noninformative priors and obtain very similar results, although when we use an informative, naturalness-motivated prior, we find some sizeable differences. We show that a further strong improvement in reconstructing the SU3 parameters can by achieved by applying additional information about the relic abundance at the level of WMAP accuracy, although the expected data from Planck will have only a very limited additional impact. Further external data may be required to break some remaining degeneracies. We argue that the method presented here is applicable to a wide class of low-energy effective supersymmetric models, as it does not require one to deal with purely experimental issues, e.g., detector performance, and has the additional advantages of computational efficiency. Furthermore, our approach allows one to distinguish the effect of the model's internal structure and of the external data on the final parameters constraints.