The Extreme Energy Events HECR array: status and perspectives

The Extreme Energy Events Project is a synchronous sparse array of 52 tracking detectors for studying High Energy Cosmic Rays (HECR) and Cosmic Rays-related phenomena. The observatory is also meant to address Long Distance Correlation (LDC) phenomena: the network is deployed over a broad area covering 10 degrees in latitude and 11 in longitude. An overview of a set of preliminary results is given, extending from the study of local muon flux dependance on solar activity to the investigation of the upward-going component of muon flux traversing the EEE stations; from the search for anisotropies at the sub-TeV scale to the hints for observations of km-scale Extensive Air Shower (EAS).Comment: XXV ECRS 2016 Proceedings - eConf C16-09-04.

The potential of eupraxia@sparc_lab for radiation based techniques

A proposal for building a Free Electron Laser, EuPRAXIA@SPARC_LAB, at the Laboratori Nazionali di Frascati, is at present under consideration. This FEL facility will provide a unique combination of a high brightness GeV-range electron beam generated in a X-band RF linac, a 0.5 PW-class laser system and the first FEL source driven by a plasma accelerator. The FEL will produce ultra-bright pulses, with up to 1012 photons/pulse, femtosecond timescale and wavelength down to 3 nm, which lies in the so called “water window”. The experimental activity will be focused on the realization of a plasma driven short wavelength FEL able to provide high-quality photons for a user beamline. In this paper, we describe the main classes of experiments that will be performed at the facility, including coherent diffraction imaging, soft X-ray absorption spectroscopy, Raman spectroscopy, Resonant Inelastic X-ray Scattering and photofragmentation measurements. These techniques will allow studying a variety of samples, both biological and inorganic, providing information about their structure and dynamical behavior. In this context, the possibility of inducing changes in samples via pump pulses leading to the stimulation of chemical reactions or the generation of coherent excitations would tremendously benefit from pulses in the soft X-ray region. High power synchronized optical lasers and a TeraHertz radiation source will indeed be made available for THz and pump–probe experiments and a split-and-delay station will allow performing XUV-XUV pump–probe experiments.Fil: Balerna, Antonella. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Bartocci, Samanta. Università degli studi di Sassari; ItaliaFil: Batignani, Giovanni. Università degli studi di Roma "La Sapienza"; ItaliaFil: Cianchi, Alessandro. Universita Tor Vergata; Italia. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Chiadroni, Enrica. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Coreno, Marcello. Istituto Nazionale Di Fisica Nucleare.; Italia. Istituto di Struttura della Materia; ItaliaFil: Cricenti, Antonio. Istituto di Struttura della Materia; ItaliaFil: Dabagov, Sultan. Istituto Nazionale Di Fisica Nucleare.; Italia. National Research Nuclear University; Rusia. Lebedev Physical Institute; RusiaFil: Di Cicco, Andrea. Universita Degli Di Camerino; ItaliaFil: Faiferri, Massimo. Università degli studi di Sassari; ItaliaFil: Ferrante, Carino. Università degli studi di Roma “La Sapienza”; Italia. Center for Life Nano Science @Sapienza; ItaliaFil: Ferrario, Massimo. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Fumero, Giuseppe. Università degli studi di Roma “La Sapienza”; ItaliaFil: Giannessi, Luca. Elettra-Sincrotrone Trieste; Italia. ENEA C.R. Frascati; ItaliaFil: Gunnella, Roberto. Universita Degli Di Camerino; ItaliaFil: Leani, Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Lupi, Stefano. Università degli studi di Roma “La Sapienza”; Italia. Istituto Nazionale di Fisica Nucleare (INFN) Sezione di Roma La Sapienza; ItaliaFil: Macis, Salvatore. Università degli Studi di Roma Tor Vergata; Italia. Istituto Nazionale di Fisica Nucleare (INFN) Sezione di Roma Tor Vergata; ItaliaFil: Manca, Rosa. Università degli studi di Sassari; ItaliaFil: Marcelli, Augusto. Istituto Nazionale Di Fisica Nucleare.; Italia. Consiglio Nazionale delle Ricerche; ItaliaFil: Masciovecchio, Claudio. Elettra-Sincrotrone Trieste; ItaliaFil: Minicucci, Marco. Universita Degli Di Camerino; ItaliaFil: Morante, Silvia. Universita Tor Vergata; Italia. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Perfetto, Enrico. Universita Tor Vergata; Italia. Consiglio Nazionale delle Ricerche; ItaliaFil: Petrarca, Massimo. Università degli studi di Roma "La Sapienza"; Italia. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Pusceddu, Fabrizio. Università degli studi di Sassari; ItaliaFil: Rezvani, Javad. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Robledo, José Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Rossi, Giancarlo. Centro Fermi—Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”; Italia. Istituto Nazionale Di Fisica Nucleare.; Italia. Universita Tor Vergata; ItaliaFil: Sanchez, Hector Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Scopigno, Tullio. Center for Life Nano Science @Sapienza; Italia. Università degli studi di Roma "La Sapienza"; ItaliaFil: Stefanucci, Gianluca. Universita Tor Vergata; Italia. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Stellato, Francesco. Universita Tor Vergata; Italia. Istituto Nazionale Di Fisica Nucleare.; ItaliaFil: Trapananti, Angela. Universita Degli Di Camerino; ItaliaFil: Villa, Fabio. Istituto Nazionale Di Fisica Nucleare.; Itali

Evidence for an excess of B -> D(*) Tau Nu decays

Based on the full BaBar data sample, we report improved measurements of the ratios R(D(*)) = B(B -> D(*) Tau Nu)/B(B -> D(*) l Nu), where l is either e or mu. These ratios are sensitive to new physics contributions in the form of a charged Higgs boson. We measure R(D) = 0.440 +- 0.058 +- 0.042 and R(D*) = 0.332 +- 0.024 +- 0.018, which exceed the Standard Model expectations by 2.0 sigma and 2.7 sigma, respectively. Taken together, our results disagree with these expectations at the 3.4 sigma level. This excess cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model. We also report the observation of the decay B -> D Tau Nu, with a significance of 6.8 sigma.Comment: Expanded section on systematics, text corrections, improved the format of Figure 2 and included the effect of the change of the Tau polarization due to the charged Higg

Search for the decay modes D^0 → e^+e^-, D^0 → μ^+μ^-, and D^0 → e^±μ∓

We present searches for the rare decay modes D^0→e^+e^-, D^0→μ^+μ^-, and D^0→e^±μ^∓ in continuum e^+e^-→cc events recorded by the BABAR detector in a data sample that corresponds to an integrated luminosity of 468  fb^(-1). These decays are highly Glashow–Iliopoulos–Maiani suppressed but may be enhanced in several extensions of the standard model. Our observed event yields are consistent with the expected backgrounds. An excess is seen in the D^0→μ^+μ^- channel, although the observed yield is consistent with an upward background fluctuation at the 5% level. Using the Feldman–Cousins method, we set the following 90% confidence level intervals on the branching fractions: B(D^0→e^+e^-)<1.7×10^(-7), B(D^0→μ^+μ^-) within [0.6,8.1]×10^(-7), and B(D^0→e^±μ^∓)<3.3×10^(-7)

Bottomonium spectroscopy and radiative transitions involving the chi(bJ)(1P, 2P) states at BABAR

We use (121 +/- 1) million Upsilon(3S) and (98 +/- 1) million Upsilon(2S) mesons recorded by the BABAR detector at the PEP-II e(+)e(-) collider at SLAC to perform a study of radiative transitions involving the chi(bJ)(1P, 2P) states in exclusive decays with mu(+)mu(-)gamma gamma final states. We reconstruct twelve channels in four cascades using two complementary methods. In the first we identify both signal photon candidates in the electromagnetic calorimeter (EMC), employ a calorimeter timing-based technique to reduce backgrounds, and determine branching-ratio products and fine mass splittings. These results include the best observational significance yet for the chi(b0)(2P) -> gamma Upsilon(2S) and chi(b0)(1P) -> gamma Upsilon(1S) transitions. In the second method, we identify one photon candidate in the EMC and one which has converted into an e(+)e(-) pair due to interaction with detector material, and we measure absolute product branching fractions. This method is particularly useful for measuring Upsilon(3S) -> gamma chi(b1,2)(1P) decays. Additionally, we provide the most up-to-date derived branching fractions, matrix elements and mass splittings for chi(b) transitions in the bottomonium system. Using a new technique, we also measure the two lowest-order spin-dependent coefficients in the nonrelativistic QCD Hamiltonian

Search for the decay modes D0 -> e+e-, D0 -> mu+mu-, and D0 -> e mu

We present searches for the rare decay modes D0 to e+e-, D0 to mu+mu- and D0 to e mu in continuum e+e- to cbar c events recorded by the BABAR detector in a data sample that corresponds to an integrated luminosity of 468 f^-1. These decays are highly GIM suppressed but may be enhanced in several extensions of the Standard Model. Our observed event yields are consistent with the expected backgrounds. An excess is seen in the D0 to mu+mu- channel, although the observed yield is consistent with an upward background fluctuation at the 5% level. Using the Feldman-Cousins method, we set the following 90% confidence level intervals on the branching fractions: B(D0 to e+e-)<1.7 x 10^-7, B(D0 to mu+mu-) within [0.6, 8.1] x 10^-7, and B(D0 to e mu)<3.3 x 10^-7.Comment: 12 pages, 4 figures, submitted to PR

Search for a light Higgs resonance in radiative decays of the (1S) with a charm tag

A search is presented for the decay (1S)→γA0, A0→cc¯, where A0 is a candidate for the CP-odd Higgs boson of the next-to-minimal supersymmetric standard model. The search is based on data collected with the BABAR detector at the (2S) resonance. A sample of (1S) mesons is selected via the decay (2S)→π+π-(1S). The A0→cc¯ decay is identified through the reconstruction of hadronic D0, D+, and D∗(2010)+ meson decays. No significant signal is observed. The measured 90% confidence-level upper limits on the product branching fraction B((1S)→γA0)×B(A0→cc¯) range from 7.4×10-5 to 2.4×10-3 for A0 masses from 4.00 to 8.95GeV/c2 and 9.10 to 9.25GeV/c2, where the region between 8.95 and 9.10GeV/c2 is excluded because of background from (2S)→γχbJ(1P), χbJ(1P)→γ(1S) decays

Observation of a Charmed Baryon Decaying to D0p at a Mass Near 2.94 GeV/c2

A search for charmed baryons decaying to D 0 p reveals two states: the Λ c ( 2880 ) + baryon and a previously unobserved state at a mass of [ 2939.8 ± 1.3 ( stat ) ± 1.0 ( syst ) ]     MeV / c 2 and with an intrinsic width of [ 17.5 ± 5.2 ( stat ) ± 5.9 ( syst ) ]     MeV . Consistent and significant signals are observed for the K − π + and K − π + π − π + decay modes of the D 0 in 287     fb − 1 annihilation data recorded by the BABAR detector at a center-of-mass energy of 10.58 GeV. There is no evidence in the D + p spectrum of doubly charged partners. The mass and intrinsic width of the Λ c ( 2880 ) + baryon and relative yield of the two baryons are also measured