Records |
Author |
Mayoral, C.; Recati, A.; Fabbri, A.; Parentani, R.; Balbinot, R.; Carusotto, I. |
Title |
Acoustic white holes in flowing atomic Bose-Einstein condensates |
Type |
Journal Article |
Year |
2011 |
Publication |
New Journal of Physics |
Abbreviated Journal |
New J. Phys. |
Volume |
13 |
Issue |
|
Pages |
025007 - 29pp |
Keywords |
|
Abstract |
We study acoustic white holes in a steadily flowing atomic Bose-Einstein condensate. A white hole configuration is obtained when the flow velocity goes from a super-sonic value in the upstream region to a sub-sonic one in the downstream region. The scattering of phonon wavepackets on a white hole horizon is numerically studied in terms of the Gross-Pitaevskii equation of mean-field theory: dynamical stability of the acoustic white hole is found, as well as a signature of a nonlinear back-action of the incident phonon wavepacket onto the horizon. The correlation pattern of density fluctuations is numerically studied by means of the truncated-Wigner method, which includes quantum fluctuations. Signatures of the white hole radiation of correlated phonon pairs by the horizon are characterized; analogies and differences with Hawking radiation from acoustic black holes are discussed. In particular, a short wavelength feature is identified in the density correlation function, whose amplitude steadily grows in time since the formation of the horizon. The numerical observations are quantitatively interpreted by means of an analytical Bogoliubov theory of quantum fluctuations for a white hole configuration within the step-like horizon approximation. |
Address |
[Recati, Alessio; Carusotto, Iacopo] Univ Trent, INO CNR BEC Ctr, I-38123 Povo, Italy, Email: carusott@science.unitn.it |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1367-2630 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000287855400003 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
556 |
Permanent link to this record |
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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.; Sanchez, J.; Torro Pastor, E.; Valladolid Gallego, E.; Valls Ferrer, J.A.; Villaplana Perez, M.; Vos, M.; Wildauer, A. |
Title |
Measurement of inclusive jet and dijet cross sections in proton-proton collisions at 7 TeV centre-of-mass energy with the ATLAS detector |
Type |
Journal Article |
Year |
2011 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
71 |
Issue |
2 |
Pages |
1512 - 59pp |
Keywords |
|
Abstract |
Jet cross sections have been measured for the first time in proton-proton collisions at a centre-of-mass energy of 7 TeV using the ATLAS detector. The measurement uses an integrated luminosity of 17 nb(-1) recorded at the Large Hadron Collider. The anti-k(t) algorithm is used to identify jets, with two jet resolution parameters, R = 0.4 and 0.6. The dominant uncertainty comes from the jet energy scale, which is determined to within 7% for central jets above 60 GeV transverse momentum. Inclusive single-jet differential cross sections are presented as functions of jet transverse momentum and rapidity. Dijet cross sections are presented as functions of dijet mass and the angular variable chi. The results are compared to expectations based on next-to-leading-order QCD, which agree with the data, providing a validation of the theory in a new kinematic regime. |
Address |
[Aad, G.; Ahles, F.; Aktas, A.; Beckingham, M.; Bernius, C.; Bianchi, R. M.; Bitenc, U.; Bruneliere, R.; Caron, S.; Carpentieri, C.; Chromek-Burckhart, D.; Dahlhoff, A.; Dietrich, J.; Eckert, S.; Fehling-Kaschek, M.; Flechl, M.; Glatzer, J.; Hartert, J.; Heldmann, M.; Herten, G.; Horner, S.; Jakobs, K.; Joos, D.; Ketterer, C.; Kollefrath, M.; Kononov, A. I.; Kuehn, S.; Lai, S.; Landgraf, U.; Lohwasser, K.; Ludwig, I.; Ludwig, J.; Lumb, D.; Maassen, M.; Mahboubi, K.; Meinhardt, J.; Messmer, I.; Mohr, W.; Nilsen, H.; Parzefall, U.; Pfeifer, B.; Bueso, X. Portell; Rammensee, M.; Runge, K.; Rurikova, Z.; Schmidt, E.; Schroff, D.; Schumacher, M.; Stoerig, K.; Sundermann, J. E.; Temming, K. K.; Thoma, S.; Tobias, J.; Venturi, M.; Vivarelli, I.; von Radziewski, H.; Warsinsky, M.; Webel, M.; Weiser, C.; Werner, M.; Wiik, L. A. M.; Winkelmann, S.; Xiea, Y.; Zimmermann, S.] Ist Nazl Fis Nucl, Lab Nazl Frascati, IT-00044 Frascati, Italy, Email: atlas.secretariat@cern.ch |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1434-6044 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000286937900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
575 |
Permanent link to this record |
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Author |
Constantinou, M.; Dimopoulos, P.; Frezzotti, R.; Jansen, K.; Gimenez, V.; Lubicz, V.; Mescia, F.; Panagopoulos, H.; Papinutto, M.; Rossi, G.C.; Simula, S.; Skouroupathis, A.; Stylianou, F.; Vladikas, A. |
Title |
B-K-parameter from N-f=2 twisted mass lattice QCD |
Type |
Journal Article |
Year |
2011 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
83 |
Issue |
1 |
Pages |
014505 - 20pp |
Keywords |
|
Abstract |
We present an unquenched N-f = 2 lattice computation of the B-K parameter which controls K-0 – (K) over bar (0) oscillations. A partially quenched setup is employed with two maximally twisted dynamical (sea) light Wilson quarks, and valence quarks of both the maximally twisted and the Osterwalder-Seiler variety. Suitable combinations of these two kinds of valence quarks lead to a lattice definition of the B-K parameter which is both multiplicatively renormalizable and O(a) improved. Employing the nonperturbative RI-MOM scheme, in the continuum limit and at the physical value of the pion mass we get B-K(RGI) = 0.729 +/- 0.030, a number well in line with the existing quenched and unquenched determinations. |
Address |
[Constantinou, M.; Panagopoulos, H.; Skouroupathis, A.; Stylianou, F.] Univ Cyprus, Dept Phys, CY-1678 Nicosia, Cyprus |
Corporate Author |
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Thesis |
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Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1550-7998 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000286761700002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
576 |
Permanent link to this record |
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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.; Sanchez, J.; Torro Pastor, E.; Valladolid Gallego, E.; Valls Ferrer, J.A.; Villaplana Perez, M.; Vos, M.; Wildauer, A. |
Title |
Search for quark contact interactions in dijet angular distributions in pp collisions at sqrt(s)=7 TeV measured with the ATLAS detector |
Type |
Journal Article |
Year |
2011 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
694 |
Issue |
4-5 |
Pages |
327-345 |
Keywords |
ATLAS; LHC; 7 TeV; Dijets angular distributions; Quark compositeness; Contact interactions |
Abstract |
Dijet angular distributions from the first LHC pp collisions at center-of-mass energy root s = 7 TeV have been measured with the ATLAS detector. The dataset used for this analysis represents an integrated luminosity of 3.1 pb(-1). Dijet chi distributions and centrality ratios have been measured up to dijet masses of 2.8 TeV, and found to be in good agreement with Standard Model predictions. Analysis of the chi distributions excludes quark contact interactions with a compositeness scale Lambda below 3.4 TeV, at 95% confidence level, significantly exceeding previous limits. |
Address |
[Aad, G.; Ahles, F.; Aktas, A.; 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.; Jakobs, K.; Joos, D.; 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.; Meinhardt, J.; Messmer, I.; Mohr, W.; Nilsen, H.; Parzefall, U.; Pfeifer, B.; Bueso, X. Portell; Rammensee, M.; Runge, K.; Rurikova, Z.; Schmidt, E.; Schroff, D.; Schumacher, M.; Stoerig, K.; Sundermann, J. E.; Temming, K. K.; Thoma, S.; Tobias, J.; Venturi, M.; Vivarelli, I.; von Radziewski, H.; Warsinsky, M.; Webel, M.; Weiser, C.; Werner, M.; Wiik, L. A. M.; Winkelmann, S.; Xie, S.; Zimmermann, S.] Univ Freiburg, Fak Math & Phys, D-79104 Freiburg, Germany |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-2693 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000286494700009 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
581 |
Permanent link to this record |
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Author |
ANTARES Collaboration (Aguilar, J.A. et al); Bigongiari, C.; Dornic, D.; Emanuele, U.; Gomez-Gonzalez, J.P.; Hernandez-Rey, J.J.; Mangano, S.; Salesa, F.; Toscano, S.; Yepes, H.; Zornoza, J.D.; Zuñiga, J. |
Title |
AMADEUS-The acoustic neutrino detection test system of the ANTARES deep-sea neutrino telescope |
Type |
Journal Article |
Year |
2011 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
Volume |
626 |
Issue |
|
Pages |
128-143 |
Keywords |
AMADEUS; ANTARES; Neutrino telescope; Acoustic neutrino detection; Thermo-acoustic model |
Abstract |
The AMADEUS (ANTARES Modules for the Acoustic Detection Under the Sea) system which is described in this article aims at the investigation of techniques for acoustic detection of neutrinos in the deep sea. It is integrated into the ANTARES neutrino telescope in the Mediterranean Sea. Its acoustic sensors, installed at water depths between 2050 and 2300 m, employ piezo-electric elements for the broad-band recording of signals with frequencies ranging up to 125 kHz. The typical sensitivity of the sensors is around – 145 dB re 1 V/mu Pa (including preamplifier). Completed in May 2008, AMADEUS consists of six “acoustic clusters”, each comprising six acoustic sensors that are arranged at distances of roughly 1 m from each other. Two vertical mechanical structures (so-called lines) of the ANTARES detector host three acoustic clusters each. Spacings between the clusters range from 14.5 to 340 m. Each cluster contains custom-designed electronics boards to amplify and digitise the acoustic signals from the sensors. An on-shore computer cluster is used to process and filter the data stream and store the selected events. The daily volume of recorded data is about 10 GB. The system is operating continuously and automatically, requiring only little human intervention. AMADEUS allows for extensive studies of both transient signals and ambient noise in the deep sea, as well as signal correlations on several length scales and localisation of acoustic point sources. Thus the system is excellently suited to assess the background conditions for the measurement of the bipolar pulses expected to originate from neutrino interactions. |
Address |
[Anton, G.; Auer, R.; Eberl, T.; Fehr, F.; Fritsch, U.; Graf, K.; Herold, B.; Hoessl, J.; Kalekin, O.; Kappes, A.; Katz, U.; Kopper, C.; Kretschmer, W.; Lahmann, R.; Laschinsky, H.; Motz, H.; Neff, M.; Ostasch, R.; Richardt, C.; Schoeck, F.; Shanidze, R.] Univ Erlangen Nurnberg, Erlangen Ctr Astroparticle Phys, D-91058 Erlangen, Germany, Email: robert.lahmann@physik.uni-erlangen.de |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0168-9002 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000286793800020 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
578 |
Permanent link to this record |