| Records |
| Author |
Borja, E.F.; Freidel, L.; Garay, I.; Livine, E.R. |
| Title |
U(N) tools for loop quantum gravity: the return of the spinor |
Type |
Journal Article |
| Year |
2011 |
Publication |
Classical and Quantum Gravity |
Abbreviated Journal |
Class. Quantum Gravity |
| Volume |
28 |
Issue |
5 |
Pages |
055005 - 28pp |
| Keywords |
|
| Abstract |
We explore the classical setting for the U(N) framework for SU(2) intertwiners for loop quantum gravity and describe the corresponding phase space in terms of spinors with the appropriate constraints. We show how its quantization leads back to the standard Hilbert space of intertwiner states defined as holomorphic functionals. We then explain how to glue these intertwiners states in order to construct spin network states as wavefunctions on the spinor phase space. In particular, we translate the usual loop gravity holonomy observables to our classical framework. Finally, we propose how to derive our phase space structure from an action principle which induces non-trivial dynamics for the spin network states. We conclude by applying explicitly our framework to states living on the simple 2-vertex graph and discuss the properties of the resulting Hamiltonian. |
| Address |
[Borja, Enrique F.; Garay, Inaki] Univ Erlangen Nurnberg, Inst Theoret Phys 3, D-91058 Erlangen, Germany, Email: etera.livine@ens-lyon.fr |
| Corporate Author |
|
Thesis |
|
| Publisher |
Iop Publishing Ltd |
Place of Publication |
|
Editor |
|
Language  |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0264-9381 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
ISI:000287308700005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
579 |
| Permanent link to this record |
| |
|
| |
| Author |
ANTARES Collaboration (Aguilar, J.A. et al); Bigongiari, C.; Emanuele, U.; Gomez-Gonzalez, J.P.; Hernandez-Rey, J.J.; Mangano, S.; Salesa, F.; Toscano, S.; Yepes, H.; Zornoza, J.D.; Zuñiga, J. |
| Title |
Measurement of the atmospheric muon flux with a 4 GeV threshold in the ANTARES neutrino telescope |
Type |
Journal Article |
| Year |
2010 |
Publication |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
| Volume |
33 |
Issue |
2 |
Pages |
86-90 |
| Keywords |
Atmospheric muons; Depth intensity relation; Potassium-40 |
| Abstract |
A new method for the measurement of the muon flux in the deep-sea ANTARES neutrino telescope and its dependence on the depth is presented. The method is based oil the observation of coincidence signals in adjacent storeys of the detector. This yields an energy threshold of about 4 GeV. The main sources of optical background are the decay of K-40 and the bioluminescence in the sea water. The K-40 background is used to calibrate the efficiency of the photo-multiplier tubes. |
| Address |
[Zaborov, D.] Inst Theoret & Expt Phys, Moscow 117218, Russia, Email: Dmitry.Zaborov@itep.ru |
| 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 |
0927-6505 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
ISI:000275514800004 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
485 |
| Permanent link to this record |
| |
|
| |
| Author |
Navarro, J.; Guardiola, R. |
| Title |
Thermal Effects on Small Para-Hydrogen Clusters |
Type |
Journal Article |
| Year |
2011 |
Publication |
International Journal of Quantum Chemistry |
Abbreviated Journal |
Int. J. Quantum Chem. |
| Volume |
111 |
Issue |
2 |
Pages |
463-471 |
| Keywords |
atomic and molecular clusters; phase transitions in clusters; structure of clusters; molecular hydrogen and isotopes |
| Abstract |
A brief review of different quantum Monte Carlo simulations of small (p-H-2)(N) clusters is presented. The clusters are viewed as a set of N structureless p-H-2 molecules, interacting via an isotropic pairwise potential. Properties as superfluidity, magic numbers, radial structure, excitation spectra, and abundance production of (p-H-2)(N) clusters are discussed and, whenever possible, a comparison with He-4(N) droplets is presented. All together, the simulations indicate that temperature has a paradoxical effect of the properties of (p-H-2)(N) clusters, as they are solid-like at high T and liquid-like at low T, due to quantum delocalization at the lowest temperature. |
| Address |
[Navarro, Jesus; Guardiola, Rafael] Univ Valencia, CSIC, IFIC, Valencia 46071, Spain, Email: navarro@ific.uv.es |
| Corporate Author |
|
Thesis |
|
| Publisher |
John Wiley & Sons Inc |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0020-7608 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
ISI:000285311400028 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
589 |
| Permanent link to this record |
| |
|
| |
| Author |
Pierre Auger Collaboration (Abraham, J. et al); Pastor, S. |
| Title |
A study of the effect of molecular and aerosol conditions in the atmosphere on air fluorescence measurements at the Pierre Auger Observatory |
Type |
Journal Article |
| Year |
2010 |
Publication |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
| Volume |
33 |
Issue |
2 |
Pages |
108-129 |
| Keywords |
Cosmic rays; Extensive air showers; Air fluorescence method; Atmosphere; Aerosols; Lidar; Bi-static lidar |
| Abstract |
The air fluorescence detector of the Pierre Auger Observatory is designed to perforin calorimetric measurements of extensive air showers created by Cosmic rays of above 10(18) eV. To correct these measurements for the effects introduced by atmospheric fluctuations, the Observatory contains a group Of monitoring instruments to record atmospheric conditions across the detector site, ail area exceeding 3000 km(2). The atmospheric data are used extensively in the reconstruction of air showers, and are particularly important for the correct determination of shower energies and the depths of shower maxima. This paper contains a summary of the molecular and aerosol conditions measured at the Pierre Auger Observatory since the start of regular operations in 2004, and includes a discussion of the impact of these measurements oil air shower reconstructions. Between 10(18) and 10(20) eV, the systematic Uncertainties due to all atmospheric effects increase from 4% to 8% in measurements of shower energy, and 4 g cm(-2) to 8 g cm(-2) in measurements of the shower maximum. |
| Address |
[BenZvi, S.; Pfendner, C.; Westerhoff, S.] Univ Wisconsin, Madison, WI 53706 USA, Email: sybenzvi@icecube.wisc.cdu |
| 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 |
0927-6505 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
ISI:000275514800007 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
486 |
| Permanent link to this record |
| |
|
| |
| Author |
ATLAS Collaboration (Aad, G. et al); Amoros, G.; Cabrera Urban, S.; Castillo Gimenez, V.; Costa, M.J.; Escobar, C.; Ferrer, A.; Fuster, J.; Garcia, C.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Kaci, M.; Lacasta, C.; Lacuesta, V.R.; Marti-Garcia, S.; Miñano, M.; Mitsou, V.A.; Moles-Valls, R.; Moreno Llacer, M.; Oliver Garcia, E.; Perez Garcia-Estañ, M.T.; Ros, E.; Salt, J.; Solans, C.A.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valladolid Gallego, E.; Valls Ferrer, J.A.; Villaplana Perez, M.; Vos, M.; Wildauer, A. |
| Title |
Measurement of underlying event characteristics using charged particles in pp collisions at sqrt(s) = 900 GeV and 7 TeV with the ATLAS detector |
Type |
Journal Article |
| Year |
2011 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
83 |
Issue |
11 |
Pages |
112001 - 34pp |
| Keywords |
|
| Abstract |
Measurements of charged particle distributions, sensitive to the underlying event, have been performed with the ATLAS detector at the LHC. The measurements are based on data collected using a minimum-bias trigger to select proton-proton collisions at center-of-mass energies of 900 GeV and 7 TeV. The "underlying event'' is defined as those aspects of a hadronic interaction attributed not to the hard scattering process, but rather to the accompanying interactions of the rest of the proton. Three regions are defined in azimuthal angle with respect to the highest transverse momentum charged particle in the event, such that the region transverse to the dominant momentum-flow is most sensitive to the underlying event. In each of these regions, distributions of the charged particle multiplicity, transverse momentum density, and average p(T) are measured. The data show generally higher underlying event activity than that predicted by Monte Carlo models tuned to pre-LHC data. |
| Address |
[Aad, G.; Ahles, F.; Beckingham, M.; Bernhard, R.; Bianchi, R. M.; Bitenc, U.; Bruneliere, R.; Caron, S.; Carpentieri, C.; Christov, A.; Dahlhoff, A.; Dietrich, J.; Eckert, S.; Fehling-Kaschek, M.; Flechl, M.; Glatzer, J.; Hartert, J.; Heldmann, M.; Herten, G.; Horner, S.; Ketterer, C.; Koenig, S.; Kollefrath, M.; Kononov, A. I.; Kuehn, S.; Lai, S.; Landgraf, U.; Lohwasser, K.; Ludwig, I.; Ludwig, J.; Lumb, D.; Maassen, M.; Mahboubi, K.; McCarthy, R. L.; Meinhardt, J.; Mohr, W.; Nilsen, H.; Parzefall, U.; Bueso, X. Portell; Rammensee, M.; Runge, K.; Rurikova, Z.; Schmidt, E.; Schumacher, M.; Siegert, F.; Stoerig, K.; Sundermann, J. E.; Temming, K. K.; Thoma, S.; Tobias, J.; Tsiskaridze, V.; Venturi, M.; Vivarelli, I.; von Radziewski, H.; Warsinsky, M.; Werner, M.; Wiik, L. A. M.; Winkelmann, S.; Xie, S.; Zimmermann, S.] Univ Freiburg, Fak Math & Phys, D-79104 Freiburg, Germany |
| Corporate Author |
|
Thesis |
|
| Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1550-7998 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
ISI:000291091000001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
635 |
| Permanent link to this record |
| |
|
| |
| Author |
Molina, R.; Nagahiro, H.; Hosaka, A.; Oset, E. |
| Title |
Decay of vector-vector resonances into gamma and a pseudoscalar meson |
Type |
Journal Article |
| Year |
2011 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
83 |
Issue |
9 |
Pages |
094030 - 12pp |
| Keywords |
|
| Abstract |
We study the decay of dynamically generated resonances from the interaction of two vectors into a gamma and a pseudoscalar meson. The dynamics requires anomalous terms involving vertices with two vectors and a pseudoscalar, which renders it special. We compare our result with data on K-2*(+) (1430) -> K+ gamma and K-2*(0) (1430) -> K-0 gamma and find a good agreement with the data for the K-2*(+) (1430) case and a width considerably smaller than the upper bound measured for the K-2*(0) (1430) meson. We also investigate the decay into pi(+) gamma of one a(2) state, tentatively associated to the a(2)(1320), obtaining qualitative agreement with data. |
| Address |
[Molina, R.; Oset, E.] Univ Valencia, CSIC, Ctr Mixto, Inst Invest Paterna,Dept Fis Teor, Valencia 46071, Spain |
| Corporate Author |
|
Thesis |
|
| Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1550-7998 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
ISI:000291006200002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
636 |
| Permanent link to this record |
| |
|
| |
| Author |
Freitas, E.D.C.; Monteiro, C.M.B.; Ball, M.; Gomez-Cadenas, J.J.; Lopes, J.A.M.; Lux, T.; Sanchez, F.; dos Santos, J.M.F. |
| Title |
Secondary scintillation yield in high-pressure xenon gas for neutrinoless double beta decay (0 nu beta beta) search |
Type |
Journal Article |
| Year |
2010 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
684 |
Issue |
4-5 |
Pages |
205-210 |
| Keywords |
Neutrino; Neutrinoless double-beta decay; Secondary scintillation; Xenon; High-pressure |
| Abstract |
The search for neutrinoless double beta decay (0 nu beta beta) is an important topic in contemporary physics with many active experiments. New projects are planning to use high-pressure xenon gas as both source and detection medium. The secondary scintillation processes available in noble gases permit large amplification with negligible statistical fluctuations, offering the prospect of energy resolution approaching the Fano factor limit. This Letter reports results for xenon secondary scintillation yield, at room temperature, as a function of electric field in the gas scintillation gap for pressures ranging from 2 to 10 bar. A Large Area Avalanche Photodiode (LAAPD) collected the VUV secondary scintillation produced in the gas. X-rays directly absorbed in the LAAPD are used as a reference for determining the number of charge carriers produced by the scintillation pulse and, hence, the number of photons impinging the LAAPD. The number of photons produced per drifting electron and per kilovolt, the so-called scintillation amplification parameter, displays a small increase with pressure, ranging from 141 +/- 6 at 2 bar to 170 +/- 10 at 8 bar. In our setup, this Parameter does not increase above 8 bar due to nonnegligible electron attachment. The results are in good agreement with those presented in the literature in the 1 to 3 bar range. The increase of the scintillation amplification parameter with pressure for high gas densities has been also observed in former work at cryogenic temperatures. |
| Address |
[Freitas, E. D. C.; Monteiro, C. M. B.; Lopes, J. A. M.; dos Santos, J. M. F.] Univ Coimbra, GIAN CI, Dept Fis, P-3004516 Coimbra, Portugal, Email: jmf@gian.fis.uc.pt |
| 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:000275009600006 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
487 |
| Permanent link to this record |
| |
|
| |
| Author |
Gomez Dumm, D.; Roig, P.; Pich, A.; Portoles, J. |
| Title |
tau -> pi pi pi nu(tau) decays and the a(1)(1260) off-shell width revisited |
Type |
Journal Article |
| Year |
2010 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
685 |
Issue |
2-3 |
Pages |
158-164 |
| Keywords |
Hadron tau decays; Chiral Lagrangians; QCD; 1/N expansion |
| Abstract |
The tau -> pi pi pi nu(tau) decay is driven by the hadronization of the axial-vector current. Within the resonance chiral theory, and considering the large-N-C expansion, this process has been studied in Ref. [1] (D. Gomez Dumm, A. Pich, J. Portoles, 2004). In the light of later developments we revise here this previous work by including a new off-shell width for the lightest a(1) resonance that provides a good description of the tau -> pi pi pi nu(tau) spectrum and branching ratio. We also consider the role of the rho(1450) resonance in these observables. Thus we bring in an overall description of the tau -> pi pi pi nu(tau) process in excellent agreement with our present experimental knowledge. |
| Address |
[Pich, A.; Portoles, J.] Univ Valencia, CSIC, Dept Fis Teor, IFIC, E-46071 Valencia, Spain, Email: Jorge.Portoles@ific.uv.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:000275148800010 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
488 |
| Permanent link to this record |
| |
|
| |
| Author |
Cabello, J.; Wells, K. |
| Title |
The spatial resolution of silicon-based electron detectors in beta-autoradiography |
Type |
Journal Article |
| Year |
2010 |
Publication |
Physics in Medicine and Biology |
Abbreviated Journal |
Phys. Med. Biol. |
| Volume |
55 |
Issue |
6 |
Pages |
1677-1699 |
| Keywords |
|
| Abstract |
Thin tissue autoradiography is an imaging modality where ex-vivo tissue sections are placed in direct contact with autoradiographic film. These tissue sections contain a radiolabelled ligand bound to a specific biomolecule under study. This radioligand emits beta- or beta+ particles ionizing silver halide crystals in the film. High spatial resolution autoradiograms are obtained using low energy radioisotopes, such as H-3 where an intrinsic 0.1-1 μm spatial resolution can be achieved. Several digital alternatives have been presented over the past few years to replace conventional film but their spatial resolution has yet to equal film, although silicon-based imaging technologies have demonstrated higher sensitivity compared to conventional film. It will be shown in this work how pixel size is a critical parameter for achieving high spatial resolution for low energy uncollimated beta imaging. In this work we also examine the confounding factors impeding silicon-based technologies with respect to spatial resolution. The study considers charge diffusion in silicon and detector noise, and this is applied to a range of radioisotopes typically used in autoradiography. Finally an optimal detector geometry to obtain the best possible spatial resolution for a specific technology and a specific radioisotope is suggested. |
| Address |
[Cabello, Jorge; Wells, Kevin] Univ Surrey, Fac Elect & Phys Sci, Ctr Vis Speech & Signal Proc, Surrey GU2 7XH, England, Email: jcabello@ific.uv.es |
| Corporate Author |
|
Thesis |
|
| Publisher |
Iop Publishing Ltd |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0031-9155 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
ISI:000275120300010 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
489 |
| Permanent link to this record |
| |
|
| |
| Author |
Pierre Auger Collaboration (Abraham, J. et al); Pastor, S. |
| Title |
Measurement of the Depth of Maximum of Extensive Air Showers above 10(18) eV |
Type |
Journal Article |
| Year |
2010 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
104 |
Issue |
9 |
Pages |
091101 - 7pp |
| Keywords |
|
| Abstract |
We describe the measurement of the depth of maximum, X-max, of the longitudinal development of air showers induced by cosmic rays. Almost 4000 events above 10(18) eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are selected for the analysis. The average shower maximum was found to evolve with energy at a rate of (106 +/- 35-21) g/cm(2)/decade below 10(18.24) +/- (0.05) eV, and d24 +/- 3 g/cm(2)/ecade above this energy. The measured shower-to-shower fluctuations decrease from about 55 to 26 g/cm(2). The interpretation of these results in terms of the cosmic ray mass composition is briefly discussed. |
| Address |
[Abraham, J.; De la Vega, G.; Garcia, B.; Videla, M.] Natl Technol Univ, Fac Mendoza, CONICET, CNEA, Mendoza, Argentina |
| Corporate Author |
|
Thesis |
|
| Publisher |
Amer Physical Soc |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0031-9007 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
ISI:000275252500006 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
490 |
| Permanent link to this record |
