IFIC Home

IFIC Literature Database

Home |  Show All |  Simple Search |  Advanced Search
Quick Search:
81-90 of 2384 records found matching your query:
toggle visibility Search & Display Options
Select All    Deselect All << 1 2 3 4 5 6 7 8 9 10 >> [11–20]
List View
 | 
Citations
 | 
Details
   print
  Records Links
Author (up) Albertus, C.; Hernandez, E.; Hidalgo-Duque, C.; Nieves, J. url  doi
openurl 
  Title (B)over-bar(s) -> K semileptonic decay from an Omnes improved constituent quark model Type Journal Article
  Year 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 738 Issue Pages 144-149  
  Keywords  
  Abstract We study the f(+) form factor for the semileptonic (B) over bar (s) -> K+ l(-) (V) over bar (l) decay in a constituent quark model. The valence quark estimate is supplemented with the contribution from the (B) over bar* pole that dominates the high q(2) region. We use a multiply-subtracted Omnes dispersion relation to extend the quark model predictions from its region of applicability near q(max)(2) = (M-Bs – M-K)(2) similar to 23.75 GeV2 to all q(2) values accessible in the physical decay. To better constrain the dependence of f(+) on q(2), we fit the subtraction constants to a combined input from previous light cone sum rule by Duplancic and Melic (2008) [11] and the present quark model results. From this analysis, we obtain Gamma ( (B) over bar (s) -> K+ l(-) (V) over bar (l)) = (5.47(-0.46)(+0.54)) vertical bar Vub vertical bar(2) x 10(-9) MeV, which is about 10% and 20% higher than the predictions based on Lattice QCD and QCD light cone sum rules respectively. The former predictions, for both the form factor f(+) (q(2)) and the differential decay width, lie within the 1 sigma band of our estimated uncertainties for all q(2) values accessible in the physical decay, except for a quite small region very close to q(max)(2). Differences with the light cone sum results for the form factor f(+) are larger than 20% in the region above q(2) = 15 GeV2.  
  Address [Albertus, C.] Univ Granada, Dept Fis Atom Nucl & Mol, E-18071 Granada, Spain  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000344624900022 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 2020  
Permanent link to this record
 
 
Author (up) Albertus, C.; Hernandez, E.; Nieves, J. url  doi
openurl 
  Title Exclusive c -> s, d semileptonic decays of ground-state spin-1/2 doubly charmed baryons Type Journal Article
  Year 2011 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 704 Issue 5 Pages 499-509  
  Keywords  
  Abstract We evaluate exclusive semileptonic decays of ground-state spin-1/2 doubly heavy charmed baryons driven by a c -> s, d transition at the quark level. Our results for the form factors are consistent with heavy quark spin symmetry constraints which are valid in the limit of an infinitely massive charm quark and near zero recoil. Only a few exclusive semileptonic decay channels have been theoretically analyzed before. For those cases we find that our results are in a reasonable agreement with previous calculations.  
  Address [Albertus, C.; Hernandez, E.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: gajatee@usal.es  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000296549200017 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ elepoucu @ Serial 828  
Permanent link to this record
 
 
Author (up) Albertus, C.; Hernandez, E.; Nieves, J. url  doi
openurl 
  Title Hyperfine mixing in electromagnetic decay of doubly heavy bc baryons Type Journal Article
  Year 2010 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 690 Issue 3 Pages 265-271  
  Keywords Hyperfine mixing; Double heavy bc baryons  
  Abstract We investigate the role of hyperfine mixing in the electromagnetic decay of ground state doubly heavy bc baryons. As in the case of a previous calculation on b -> c semileptonic decays of doubly heavy baryons, we find large corrections to the electromagnetic decay widths due to this mixing. Contrary to the weak case just mentioned, we find here that one cannot use electromagnetic width relations obtained in the infinite heavy quark mass limit to experimentally extract information on the admixtures in a model independent way.  
  Address [Albertus, C.; Hernandez, E.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: gajatee@usal.es  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000279388800012 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ elepoucu @ Serial 416  
Permanent link to this record
 
 
Author (up) Albertus, C.; Hernandez, E.; Nieves, J. url  doi
openurl 
  Title Hyperfine mixing in b -> c semileptonic decay of doubly heavy baryons Type Journal Article
  Year 2010 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 683 Issue 1 Pages 21-25  
  Keywords  
  Abstract We qualitatively corroborate the results of [W. Roberts, M. Pervin, Int. J. Mod. Phys. A 24 (2009) 2401] according to which hyperfine mixing greatly affects the decay widths of b -> c semileptonic decays involving doubly heavy bc baryons. However, our predictions for the decay widths of the unmixed states differ from those reported in the work of Roberts and Pervin by a factor of 2, and this discrepancy translates to the mixed case. We further show that the predictions of heavy quark spin symmetry, might be used in the future to experimentally extract information on the admixtures in the actual physical bc baryons, in a model independent manner.  
  Address [Hernandez, E.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: gajatee@usal.es  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000274129600005 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ elepoucu @ Serial 501  
Permanent link to this record
 
 
Author (up) Albiol, A.; Corbi, A.; Albiol, F. doi  openurl
  Title Automatic intensity windowing of mammographic images based on a perceptual metric Type Journal Article
  Year 2017 Publication Medical Physics Abbreviated Journal Med. Phys.  
  Volume 44 Issue 4 Pages 1369-1378  
  Keywords contrast stretching; Gabor filtering; human visual system; mammogram; mutual information; window level/width  
  Abstract Purpose: Initial auto-adjustment of the window level WL and width WW applied to mammographic images. The proposed intensity windowing (IW) method is based on the maximization of the mutual information (MI) between a perceptual decomposition of the original 12-bit sources and their screen displayed 8-bit version. Besides zoom, color inversion and panning operations, IW is the most commonly performed task in daily screening and has a direct impact on diagnosis and the time involved in the process. Methods: The authors present a human visual system and perception-based algorithm named GRAIL (Gabor-relying adjustment of image levels). GRAIL initially measures a mammogram's quality based on the MI between the original instance and its Gabor-filtered derivations. From this point on, the algorithm performs an automatic intensity windowing process that outputs the WL/WW that best displays each mammogram for screening. GRAIL starts with the default, high contrast, wide dynamic range 12-bit data, and then maximizes the graphical information presented in ordinary 8-bit displays. Tests have been carried out with several mammogram databases. They comprise correlations and an ANOVA analysis with the manual IW levels established by a group of radiologists. A complete MATLAB implementation of GRAIL is available at . Results: Auto-leveled images show superior quality both perceptually and objectively compared to their full intensity range and compared to the application of other common methods like global contrast stretching (GCS). The correlations between the human determined intensity values and the ones estimated by our method surpass that of GCS. The ANOVA analysis with the upper intensity thresholds also reveals a similar outcome. GRAIL has also proven to specially perform better with images that contain micro-calcifications and/or foreign X-ray-opaque elements and with healthy BI-RADS A-type mammograms. It can also speed up the initial screening time by a mean of 4.5 s per image. Conclusions: A novel methodology is introduced that enables a quality-driven balancing of the WL/WW of mammographic images. This correction seeks the representation that maximizes the amount of graphical information contained in each image. The presented technique can contribute to the diagnosis and the overall efficiency of the breast screening session by suggesting, at the beginning, an optimal and customized windowing setting for each mammogram.  
  Address [Albiol, Alberto] Univ Politecn Valencia, iTeam Res Inst, Valencia, Spain, Email: alberto.corbi@ific.uv.es  
  Corporate Author Thesis  
  Publisher Wiley Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0094-2405 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000400572700016 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 3122  
Permanent link to this record
 
 
Author (up) Albiol, F.; Corbi, A.; Albiol, A. doi  openurl
  Title 3D measurements in conventional X-ray imaging with RGB-D sensors Type Journal Article
  Year 2017 Publication Medical Engineering & Physics Abbreviated Journal Med. Eng. Phys.  
  Volume 42 Issue Pages 73-79  
  Keywords X-ray; Depth cameras; Epipolar geometry; 3D reconstruction; Movement tracking; Dense surface mapping  
  Abstract A method for deriving 3D internal information in conventional X-ray settings is presented. It is based on the combination of a pair of radiographs from a patient and it avoids the use of X-ray-opaque fiducials and external reference structures. To achieve this goal, we augment an ordinary X-ray device with a consumer RGB-D camera. The patient' s rotation around the craniocaudal axis is tracked relative to this camera thanks to the depth information provided and the application of a modern surface-mapping algorithm. The measured spatial information is then translated to the reference frame of the X-ray imaging system. By using the intrinsic parameters of the diagnostic equipment, epipolar geometry, and X-ray images of the patient at different angles, 3D internal positions can be obtained. Both the RGB-D and Xray instruments are first geometrically calibrated to find their joint spatial transformation. The proposed method is applied to three rotating phantoms. The first two consist of an anthropomorphic head and a torso, which are filled with spherical lead bearings at precise locations. The third one is made of simple foam and has metal needles of several known lengths embedded in it. The results show that it is possible to resolve anatomical positions and lengths with a millimetric level of precision. With the proposed approach, internal 3D reconstructed coordinates and distances can be provided to the physician. It also contributes to reducing the invasiveness of ordinary X-ray environments and can replace other types of clinical explorations that are mainly aimed at measuring or geometrically relating elements that are present inside the patient's body.  
  Address [Albiol, Francisco; Corbi, Alberto] Univ Valencia, CSIC, Inst Fis Corpuscular, E-46003 Valencia, Spain, Email: alberto.corbi@ific.uv.es  
  Corporate Author Thesis  
  Publisher Elsevier Sci Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1350-4533 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000398007100008 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 3043  
Permanent link to this record
 
 
Author (up) Albiol, F.; Corbi, A.; Albiol, A. doi  openurl
  Title Evaluation of modern camera calibration techniques for conventional diagnostic X-ray imaging settings Type Journal Article
  Year 2017 Publication Radiological Physics and Technology Abbreviated Journal Radiol. Phys. Technol.  
  Volume 10 Issue 1 Pages 68-81  
  Keywords Conventional X-ray camera calibration; Detector resolution; Intrinsic and extrinsic parameters; Zhang's method; Direct linear transform; Tsai's approach  
  Abstract We explore three different alternatives for obtaining intrinsic and extrinsic parameters in conventional diagnostic X-ray frameworks: the direct linear transform (DLT), the Zhang method, and the Tsai approach. We analyze and describe the computational, operational, and mathematical background differences for these algorithms when they are applied to ordinary radiograph acquisition. For our study, we developed an initial 3D calibration frame with tin cross-shaped fiducials at specific locations. The three studied methods enable the derivation of projection matrices from 3D to 2D point correlations. We propose a set of metrics to compare the efficiency of each technique. One of these metrics consists of the calculation of the detector pixel density, which can be also included as part of the quality control sequence in general X-ray settings. The results show a clear superiority of the DLT approach, both in accuracy and operational suitability. We paid special attention to the Zhang calibration method. Although this technique has been extensively implemented in the field of computer vision, it has rarely been tested in depth in common radiograph production scenarios. Zhang's approach can operate on much simpler and more affordable 2D calibration frames, which were also tested in our research. We experimentally confirm that even three or four plane-image correspondences achieve accurate focal lengths.  
  Address [Albiol, Francisco; Corbi, Alberto] Univ Valencia, CSIC, Inst Fis Corpuscular, Valencia, Spain, Email: alberto.corbi@ific.uv.es  
  Corporate Author Thesis  
  Publisher Springer Japan Kk Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1865-0333 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000405867100009 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 3238  
Permanent link to this record
 
 
Author (up) Alcaide, J.; Banerjee, S.; Chala, M.; Titov, A. url  doi
openurl 
  Title Probes of the Standard Model effective field theory extended with a right-handed neutrino Type Journal Article
  Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 08 Issue 8 Pages 031 - 18pp  
  Keywords Beyond Standard Model; Effective Field Theories; Neutrino Physics  
  Abstract If neutrinos are Dirac particles and, as suggested by the so far null LHC results, any new physics lies at energies well above the electroweak scale, the Standard Model effective field theory has to be extended with operators involving the right-handed neutrinos. In this paper, we study this effective field theory and set constraints on the different dimension-six interactions. To that aim, we use LHC searches for associated production of light (and tau) leptons with missing energy, monojet searches, as well as pion and tau decays. Our bounds are generally above the TeV for order one couplings. One particular exception is given by operators involving top quarks. These provide new signals in top decays not yet studied at colliders. Thus, we also design an LHC analysis to explore these signatures in the tt production. Our results are also valid if the right-handed neutrinos are Majorana and long-lived.  
  Address [Alcaide, Julien] Univ Valencia, Dept Fis Teor, Dr Moliner 50, E-46100 Burjassot, Spain, Email: julien.alcaide@uv.es;  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1029-8479 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000482463900008 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4120  
Permanent link to this record
 
 
Author (up) Alcaide, J.; Chala, M.; Santamaria, A. url  doi
openurl 
  Title LHC signals of radiatively-induced neutrino masses and implications for the Zee-Babu model Type Journal Article
  Year 2018 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 779 Issue Pages 107-116  
  Keywords Lepton-number violation; LHC searches; Higgs sector; Doubly-charged scalars  
  Abstract Contrary to the see-saw models, extended Higgs sectors leading to radiatively-induced neutrino masses do require the extra particles to be at the TeV scale. However, these new states have often exotic decays, to which experimental LHC searches performed so far, focused on scalars decaying into pairs of same-sign leptons, are not sensitive. In this paper we show that their experimental signatures can start to be tested with current LHC data if dedicated multi-region analyses correlating different observables are used. We also provide high-accuracy estimations of the complicated Standard Model backgrounds involved. For the case of the Zee-Babu model, we show that regions not yet constrained by neutrino data and low-energy experiments can be already probed, while most of the parameter space could be excluded at the 95% C.L. in a high-luminosity phase of the LHC.  
  Address [Chala, Mikael] Univ Valencia, Dept Fis Teor, Dr Moliner 50, E-46100 Burjassot, Valencia, Spain, Email: mikael.chala@cern.ch  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-2693 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000429098900012 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 3565  
Permanent link to this record
 
 
Author (up) Alcaide, J.; Das, D.; Santamaria, A. url  doi
openurl 
  Title A model of neutrino mass and dark matter with large neutrinoless double beta decay Type Journal Article
  Year 2017 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 04 Issue 4 Pages 049 - 21pp  
  Keywords Beyond Standard Model; Higgs Physics; Neutrino Physics  
  Abstract We propose a model where neutrino masses are generated at three loop order but neutrinoless double beta decay occurs at one loop. Thus we can have large neutrinoless double beta decay observable in the future experiments even when the neutrino masses are very small. The model receives strong constraints from the neutrino data and lepton flavor violating decays, which substantially reduces the number of free parameters. Our model also opens up the possibility of having several new scalars below the TeV regime, which can be explored at the collider experiments. Additionally, our model also has an unbroken Z(2) symmetry which allows us to identify a viable Dark Matter candidate.  
  Address [Alcaide, Julien] Univ Valencia, Dept Fis Teor, Dr Moliner 50, E-46100 Burjassot, Valencia, Spain, Email: julien.alcaide@uv.es;  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1029-8479 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000399275900008 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 3067  
Permanent link to this record
Select All    Deselect All << 1 2 3 4 5 6 7 8 9 10 >> [11–20]
List View
 | 
Citations
 | 
Details
   print
toggle visibility
Save Citations:
Export Records:
Home CQL Search  |  Library Search  |  Show Record  |  Extract Citations Help
ific federMinisterio de Ciencia e InnovaciónAgencia Estatal de Investigaciongva