The Planck-LFI instrument: analysis of the 1/f noise and implications for the scanning strategy

We study the impact of the 1/f noise on the PLANCK Low Frequency Instrument (LFI) osbervations (Mandolesi et al 1998) and describe a simple method for removing striping effects from the maps for a number of different scanning stategies. A configuration with an angle between telescope optical axis and spin-axis just less than 90 degrees (namely 85 degress) shows good destriping efficiency for all receivers in the focal plane, with residual noise degradation < 1-2 %. In this configuration, the full sky coverage can be achieved for each channel separately with a 5 degrees spin-axis precession to maintain a constant solar aspect angle.Comment: submitted to Astronomy and Astrophysics, 12 pages, 15 PostSript figure

Associated Production of a W Boson and One b Jet

We calculate the production of a W boson and a single b jet to next-to-leading order in QCD at the Fermilab Tevatron and the CERN Large Hadron Collider. Both exclusive and inclusive cross sections are presented. We separately consider the cross section for jets containing a single b quark and jets containing a b-anti b pair. There are a wide variety of processes that contribute, and it is necessary to include them all in order to have a complete description at both colliders.Comment: LaTeX, 16 pages, 22 postscript figures; version published in Phys. Rev.

Associated production of Higgs and single top at hadron colliders

We study the production of the Higgs boson in association with a single top quark at hadron colliders. The cross sections for the three production processes (t-channel, s-channel, and W-associated) at both the Tevatron and the LHC are presented. We investigate the possibility of detecting a signal for the largest of these processes, the t-channel process at the LHC, via the Higgs decay into b b-bar. The QCD backgrounds are large and difficult to curb, hindering the extraction of the signal. Extensions of our analysis to the production of supersymmetric Higgs bosons are also addressed. The cross section is enhanced for large values of tangent beta, increasing the prospects for extracting a signal

Comparison of the color-evaporation model and the NRQCD factorization approach in charmonium production

We compare the color-evaporation model (CEM) and nonrelativistic QCD (NRQCD) factorization predictions for inclusive quarkonium production. Using the NRQCD factorization formulas for quarkonium production and for perturbative QQ-bar production, we deduce relationships that are implied by the CEM between the nonperturbative NRQCD matrix elements that appear in the factorization formula for quarkonium production. These relationships are at odds with the phenomenological values of the matrix elements that have been extracted from the Tevatron data for charmonium production at large transverse momentum. A direct comparison of the CEM and NRQCD factorization predictions with the CDF charmonium production data reveals that the CEM fits to the data are generally unsatisfactory, while the NRQCD factorization fits are generally compatible with the data. The inclusion of k_T smearing improves the CEM fits substantially, but significant incompatibilities remain. The NRQCD factorization fits to the chi_c data indicate that multiple gluon radiation is an essential ingredient in obtaining the correct shape of the cross section as a function of p_T.Comment: 26 pages, 6 figures, 7 tables, Some changes of emphasis in the conclusions, additional discussion of theoretical uncertainties, minor revisions and corrections, version to be published in Physical Review

Fuzzy models for fingerprint description

Fuzzy models, traditionally used in the control field to model controllers or plants behavior, are used in this work to describe fingerprint images. The textures, in this case the directions of the fingerprint ridges, are described for the whole image by fuzzy if-then rules whose antecedents consider a part of the image and the consequent is the associated dominant texture. This low-level fuzzy model allows extracting higher-level information about the fingerprint, such as the existence of fuzzy singular points and their fuzzy position within the image. This is exploited in two applications: to provide comprehensive information for user of unattended automatic recognition systems and to extract linguistic patterns to classify fingerprints

NLO QCD corrections to hadronic Higgs production with heavy quarks

The production of a Higgs boson in association with a pair of top-antitop or bottom-antibottom quarks plays a very important role at both the Tevatron and the Large Hadron Collider. The theoretical prediction of the corresponding cross sections has been improved by including the complete next-to-leading order QCD corrections. After a brief description of the most relevant technical aspects of the calculation, we review the results obtained for both the Tevatron and the Large Hadron ColliderComment: 6 pages, 6 figures, espcrc2.sty. Talk given at the International Conference QCD03, 2-7 July 2003, Montpellier, France. To be published in Nucl. Phys. B Proc. Supp

Invisible Higgs Boson Decay into Massive Neutrinos of 4th Generation

Results from several recent experiments provide inderect evidences in the favor of existence of a 4th generation neutrino. Such a neutrino of mass about 50 GeV is compatible with current physical and astrophysical constraints and well motivated in the framework of superstring phenomenology. If sufficiently stable the existence of such a neutrino leads to the drastic change of Higgs boson physics: for a wide range of Higgs boson masses the dominant mode of Higgs boson decay is invisible and the branching ratios for the most promising modes of Higgs boson search are significantly reduced. The proper strategy of Higgs boson searches in such a framework is discussed. It is shown that in the same framework the absence of a signal in the search for invisible Higgs boson decay at LEP means either that the mass of Higgs is greater than 113.5 GeV or that the mass difference between the Higgs mass and doubled neutrino mass is small.Comment: 8 pages, 2 figure