Two Axis Pointing System (TAPS) attitude acquisition, determination, and control

The Two Axis Pointing System (TAPS) is a 2 axis gimbal system designed to provide fine pointing of Space Transportation System (STS) borne instruments. It features center-of-mass instrument mounting and will accommodate instruments of up to 1134 kg (2500 pounds) which fit within a 1.0 by 1.0 by 4.2 meter (40 by 40 by 166 inch) envelope. The TAPS system is controlled by a microcomputer based Control Electronics Assembly (CEA), a Power Distribution Unit (PDU), and a Servo Control Unit (SCU). A DRIRU-II inertial reference unit is used to provide incremental angles for attitude propagation. A Ball Brothers STRAP star tracker is used for attitude acquisition and update. The theory of the TAPS attitude determination and error computation for the Broad Band X-ray Telescope (BBXRT) are described. The attitude acquisition is based upon a 2 star geometric solution. The acquisition theory and quaternion algebra are presented. The attitude control combines classical position, integral and derivative (PID) control with techniques to compensate for coulomb friction (bias torque) and the cable harness crossing the gimbals (spring torque). Also presented is a technique for an adaptive bias torque compensation which adjusts to an ever changing frictional torque environment. The control stability margins are detailed, with the predicted pointing performance, based upon simulation studies. The TAPS user interface, which provides high level operations commands to facilitate science observations, is outlined

Search for Neutrinoless Double-Beta Decay of 130^{130}Te with CUORE-0

We report the results of a search for neutrinoless double-beta decay in a 9.8~kg$\cdot$yr exposure of $^{130}$Te using a bolometric detector array, CUORE-0. The characteristic detector energy resolution and background level in the region of interest are $5.1\pm 0.3{\rm~keV}$ FWHM and $0.058 \pm 0.004\,(\mathrm{stat.})\pm 0.002\,(\mathrm{syst.})$~counts/(keV$\cdot$kg$\cdot$yr), respectively. The median 90%~C.L. lower-limit sensitivity of the experiment is $2.9\times 10^{24}~{\rm yr}$ and surpasses the sensitivity of previous searches. We find no evidence for neutrinoless double-beta decay of $^{130}$Te and place a Bayesian lower bound on the decay half-life, $T^{0\nu}_{1/2}>$~$2.7\times 10^{24}~{\rm yr}$ at 90%~C.L. Combining CUORE-0 data with the 19.75~kg$\cdot$yr exposure of $^{130}$Te from the Cuoricino experiment we obtain $T^{0\nu}_{1/2} > 4.0\times 10^{24}~\mathrm{yr}$ at 90%~C.L.~(Bayesian), the most stringent limit to date on this half-life. Using a range of nuclear matrix element estimates we interpret this as a limit on the effective Majorana neutrino mass, $m_{\beta\beta}< 270$ -- $760~\mathrm{meV}$.Comment: 6 pages, 5 figures, updated version as published in PR

Analysis Techniques for the Evaluation of the Neutrinoless Double-Beta Decay Lifetime in 130^{130}Te with CUORE-0

We describe in detail the methods used to obtain the lower bound on the lifetime of neutrinoless double-beta ($0\nu\beta\beta$) decay in $^{130}$Te and the associated limit on the effective Majorana mass of the neutrino using the CUORE-0 detector. CUORE-0 is a bolometric detector array located at the Laboratori Nazionali del Gran Sasso that was designed to validate the background reduction techniques developed for CUORE, a next-generation experiment scheduled to come online in 2016. CUORE-0 is also a competitive $0\nu\beta\beta$ decay search in its own right and functions as a platform to further develop the analysis tools and procedures to be used in CUORE. These include data collection, event selection and processing, as well as an evaluation of signal efficiency. In particular, we describe the amplitude evaluation, thermal gain stabilization, energy calibration methods, and the analysis event selection used to create our final $0\nu\beta\beta$ decay search spectrum. We define our high level analysis procedures, with emphasis on the new insights gained and challenges encountered. We outline in detail our fitting methods near the hypothesized $0\nu\beta\beta$ decay peak and catalog the main sources of systematic uncertainty. Finally, we derive the $0\nu\beta\beta$ decay half-life limits previously reported for CUORE-0, $T^{0\nu}_{1/2}>2.7\times10^{24}$ yr, and in combination with the Cuoricino limit, $T^{0\nu}_{1/2}>4.0\times10^{24}$ yr.Comment: 18 pages, 18 figures. (Version 3 reflects only minor changes to the text. Few additional details, no major content changes.

Exploring the Neutrinoless Double Beta Decay in the Inverted Neutrino Hierarchy with Bolometric Detectors

Neutrinoless double beta decay (0nubb) is one of the most sensitive probes for physics beyond the Standard Model, providing unique information on the nature of neutrinos. In this paper we review the status and outlook for bolometric 0nubb decay searches. We summarize recent advances in background suppression demonstrated using bolometers with simultaneous readout of heat and light signals. We simulate several configurations of a future CUORE-like bolometer array which would utilize these improvements and present the sensitivity reach of a hypothetical next-generation bolometric 0nubb experiment. We demonstrate that a bolometric experiment with the isotope mass of about 1 ton is capable of reaching the sensitivity to the effective Majorana neutrino mass (|mee|) of order 10-20 meV, thus completely exploring the so-called inverted neutrino mass hierarchy region. We highlight the main challenges and identify priorities for an R&D program addressing them.Comment: 22 pages, 15 figures, submitted to EPJ

Search for 14.4 keV solar axions from M1 transition of Fe-57 with CUORE crystals

We report the results of a search for axions from the 14.4 keV M1 transition from Fe-57 in the core of the sun using the axio-electric effect in TeO2 bolometers. The detectors are 5x5x5 cm3 crystals operated at about 10 mK in a facility used to test bolometers for the CUORE experiment at the Laboratori Nazionali del Gran Sasso in Italy. An analysis of 43.65 kg d of data was made using a newly developed low energy trigger which was optimized to reduce the detectors energy threshold. An upper limit of 0.63 c kg-1 d-1 was established at 95% C.L.. From this value, a lower bound at 95% C.L. was placed on the Peccei-Quinn energy scale of fa >= 0.76 10**6 GeV for a value of S=0.55 for the flavor-singlet axial vector matrix element. Bounds are given for the interval 0.15 < S < 0.55.Comment: 14 pages, 6 figures, submitted to JCA

The low energy spectrum of TeO2 bolometers: results and dark matter perspectives for the CUORE-0 and CUORE experiments

We collected 19.4 days of data from four 750 g TeO2 bolometers, and in three of them we were able to set the energy threshold around 3 keV using a new analysis technique. We found a background rate ranging from 25 cpd/keV/kg at 3 keV to 2 cpd/keV/kg at 25 keV, and a peak at 4.7 keV. The origin of this peak is presently unknown, but its presence is confirmed by a reanalysis of 62.7 kg.days of data from the finished CUORICINO experiment. Finally, we report the expected sensitivities of the CUORE0 (52 bolometers) and CUORE (988 bolometers) experiments to a WIMP annual modulation signal.Comment: 9 pages, 10 figure

Measurement of the t-channel single top quark production cross section in pp collisions at √s =7 TeV

Peer reviewe

Observation of Long-Range, Near-Side Angular Correlations in Proton-Proton Collisions at the LHC

Peer reviewe

Evidence for the η_b(1S) Meson in Radiative Υ(2S) Decay

We have performed a search for the η_b(1S) meson in the radiative decay of the Υ(2S) resonance using a sample of 91.6 × 10^6 Υ(2S) events recorded with the BABAR detector at the PEP-II B factory at the SLAC National Accelerator Laboratory. We observe a peak in the photon energy spectrum at E_γ = 609.3^(+4.6)_(-4.5)(stat)±1.9(syst) MeV, corresponding to an η_b(1S) mass of 9394.2^(+4.8)_(-4.9)(stat) ± 2.0(syst) MeV/c^2. The branching fraction for the decay Υ(2S) → γη_b(1S) is determined to be [3.9 ± 1.1(stat)^(+1.1)_(-0.9)(syst)] × 10^(-4). We find the ratio of branching fractions B[Υ(2S) → γη_b(1S)]/B[Υ(3S) → γη_b(1S)]= 0.82 ± 0.24(stat)^(+0.20)_(-0.19)(syst)

Evidence for the Rare Decay B -> K*ll and Measurement of the B -> Kll Branching Fraction

We present evidence for the flavor-changing neutral current decay $B\to K^*\ell^+\ell^-$ and a measurement of the branching fraction for the related process $B\to K\ell^+\ell^-$, where $\ell^+\ell^-$ is either an $e^+e^-$ or $\mu^+\mu^-$ pair. These decays are highly suppressed in the Standard Model, and they are sensitive to contributions from new particles in the intermediate state. The data sample comprises $123\times 10^6$ $\Upsilon(4S)\to B\bar{B}$ decays collected with the Babar detector at the PEP-II $e^+e^-$ storage ring. Averaging over $K^{(*)}$ isospin and lepton flavor, we obtain the branching fractions ${\mathcal B}(B\to K\ell^+\ell^-)=(0.65^{+0.14}_{-0.13}\pm 0.04)\times 10^{-6}$ and ${\mathcal B}(B\to K^*\ell^+\ell^-)=(0.88^{+0.33}_{-0.29}\pm 0.10)\times 10^{-6}$, where the uncertainties are statistical and systematic, respectively. The significance of the $B\to K\ell^+\ell^-$ signal is over $8\sigma$, while for $B\to K^*\ell^+\ell^-$ it is $3.3\sigma$.Comment: 7 pages, 2 postscript figues, submitted to Phys. Rev. Let