Records |
Author |
ATLAS Collaboration (Aad, G. et al); Alvarez Piqueras, D.; Cabrera Urban, S.; Castillo Gimenez, V.; Costa, M.J.; Fernandez Martinez, P.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Jimenez Pena, J.; Kaci, M.; King, M.; Lacasta, C.; Lacuesta, V.R.; Marti-Garcia, S.; Mitsou, V.A.; Moles-Valls, R.; Oliver Garcia, E.; Pedraza Lopez, S.; Perez Garcia-Estañ, M.T.; Romero Adam, E.; Ros, E.; Salt, J.; Sanchez Martinez, V.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valladolid Gallego, E.; Valls Ferrer, J.A.; Vos, M. |
Title |
Analysis of events with b-jets and a pair of leptons of the same charge in pp collisions at p root s=8 TeV with the ATLAS detector |
Type |
Journal Article |
Year |
2015 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
10 |
Issue |
10 |
Pages |
150 - 51pp |
Keywords |
Exotics; Lepton production; Hadron-Hadron Scattering; Beyond Standard Model; vector-like quarks; four-top-production; chiral b'; same charge top pair |
Abstract |
An analysis is presented of events containing jets including at least one b tagged jet, sizeable missing transverse momentum, and at least two leptons including a pair of the same electric charge, with the scalar sum of the jet and lepton transverse momenta being large. A data sample with an integrated luminosity of 20.3 fb(-1) of p p collisions at p root s = 8TeV recorded by the ATLAS detector at the Large Hadron Collider is used. Standard Model processes rarely produce these final states, but there are several models of physics beyond the Standard Model that predict an enhanced rate of production of such events; the ones considered here are production of vector-like quarks, enhanced fourtop- quark production, pair production of chiral b'-quarks, and production of two positively charged top quarks. Eleven signal regions are defined; subsets of these regions are combined when searching for each class of models. In the three signal regions primarily sensitive to positively charged top quark pair production, the data yield is consistent with the background expectation. There are more data events than expected from background in the set of eight signal regions defined for searching for vector-like quarks and chiral b'-quarks, but the significance of the discrepancy is less than two standard deviations. The discrepancy reaches 2.5 standard deviations in the set of five signal regions defined for searching for four-top-quark production. The results are used to set 95% CL limits on various models. |
Address |
[Jackson, P.; Lee, L.; Soni, N.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
Corporate Author |
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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 |
1029-8479 |
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 |
WOS:000373570900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2615 |
Permanent link to this record |
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Author |
de Azcarraga, J.A.; Fedoruk, S.; Izquierdo, J.M.; Lukierski, J. |
Title |
Two-twistor particle models and free massive higher spin fields |
Type |
Journal Article |
Year |
2015 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
04 |
Issue |
4 |
Pages |
010 - 39pp |
Keywords |
Field Theories in Lower Dimensions; Higher Spin Symmetry; Extended Supersymmetry; Space-Time Symmetries |
Abstract |
We present D = 3 and D = 4 world-line models for massive particles moving in a new type of enlarged spacetime, with D-1 additional vector coordinates, which after quantization lead to towers of massive higher spin (HS) free fields. Two classically equivalent formulations are presented: one with a hybrid spacetime/bispinor variables and a second described by a free two-twistor dynamics with constraints. After first quantization in the D = 3 and D = 4 cases, the wave functions satisfying a massive version of Vasiliev's free unfolded equations are given as functions on the SL(2, R) and SL(2, C) group manifolds respectively, which describe arbitrary on-shell momenta and spin degrees of freedom. Further we comment on the D = 6 case, and possible supersymmetric extensions are mentioned as well. Finally, the description of interactions and the Ads/crr duality are briefly considered for massive IHS fields. |
Address |
[de Azcarraga, J. A.] Univ Valencia, Dept Theoret Phys, E-46100 Burjassot, Valencia, Spain, Email: j.a.de.azcarraga@ific.uv.es; |
Corporate Author |
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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 |
1029-8479 |
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 |
WOS:000356852000010 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2293 |
Permanent link to this record |
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Author |
Barrientos, D.; Bellato, M.; Bazzacco, D.; Bortolato, D.; Cocconi, P.; Gadea, A.; Gonzalez, V.; Gulmini, M.; Isocrate, R.; Mengoni, D.; Pullia, A.; Recchia, F.; Rosso, D.; Sanchis, E.; Toniolo, N.; Ur, C.A.; Valiente-Dobon, J.J. |
Title |
Performance of the Fully Digital FPGA-Based Front-End Electronics for the GALILEO Array |
Type |
Journal Article |
Year |
2015 |
Publication |
IEEE Transactions on Nuclear Science |
Abbreviated Journal |
IEEE Trans. Nucl. Sci. |
Volume |
62 |
Issue |
6 |
Pages |
3134-3139 |
Keywords |
FPGA; front-end electronics; gamma-ray spectroscopy; germanium detectors |
Abstract |
In this work we present the architecture and results of a fully digital Front End Electronics (FEE) read out system developed for the GALILEO array. The FEE system, developed in collaboration with the Advanced Gamma Tracking Array (AGATA) collaboration, is composed of three main blocks: preamplifiers, digitizers and preprocessing electronics. The slow control system contains a custom Linux driver, a dynamic library and a server implementing network services. This work presents the first results of the digital FEE system coupled with a GALILEO germanium detector, which has demonstrated the capability to achieve an energy resolution of 1.53% at an energy of 1.33 MeV, similar to the one obtained with a conventional analog system. While keeping a good performance in terms of energy resolution, digital electronics will allow to instrument the full GALILEO array with a versatile system with high integration and low power consumption and costs. |
Address |
[Barrientos, D.; Bortolato, D.; Cocconi, P.; Gulmini, M.; Rosso, D.; Toniolo, N.; Valiente-Dobon, J. J.] Ist Nazl Fis Nucl, Lab Nazl Legnaro, I-35020 Padua, Italy, Email: diego.barrientos@lnl.infn.it |
Corporate Author |
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Thesis |
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Publisher |
Ieee-Inst Electrical Electronics Engineers Inc |
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 |
0018-9499 |
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 |
WOS:000372013500005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2612 |
Permanent link to this record |
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Author |
Doncel, M.; Cederwall, B.; Martin, S.; Quintana, B.; Gadea, A.; Farnea, E.; Algora, A. |
Title |
Conceptual design of a high resolution Ge array with tracking and imaging capabilities for the DESPEC (FAIR) experiment |
Type |
Journal Article |
Year |
2015 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
Volume |
10 |
Issue |
|
Pages |
P06010 - 15pp |
Keywords |
Gamma detectors (scintillators, CZT, HPG, HgI etc); Detector modelling and simulations I (interaction of radiation with matter, interaction of photons with matter, interaction of hadrons with matter, etc) |
Abstract |
We present results of Monte Carlo simulations for the conceptual design of the high-resolution DESPEC Germanium Array Spectrometer (DEGAS) proposed for the Facility for Ion and Antiproton Research (FAIR) under construction at Darmstadt, Germany. The project is carried out in three phases, although only results for the two first phases will be addressed in this work. The first phase will consist of a re-arrangement of the EUROBALL cluster detectors previously used in the RISING campaign at GSI. The second phase is based on coupling AGATA-type triple-cluster detectors with EUROBALL cluster detectors in a compact geometry around the active ion implantation target of DESPEC. |
Address |
[Doncel, M.; Cederwall, B.] Royal Inst Technol, Dept Phys, S-10691 Stockholm, Sweden, Email: doncel@kth.se |
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 |
1748-0221 |
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 |
WOS:000358004200026 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2316 |
Permanent link to this record |
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Author |
Mendoza, S.; Olmo, G.J. |
Title |
Astrophysical constraints and insights on extended relativistic gravity |
Type |
Journal Article |
Year |
2015 |
Publication |
Astrophysics and Space Science |
Abbreviated Journal |
Astrophys. Space Sci. |
Volume |
357 |
Issue |
2 |
Pages |
133 - 6pp |
Keywords |
Gravitation; Relativistic processes; Gravitational lensing: weak |
Abstract |
We give precise details to support that observations of gravitational lensing at scales of individual, groups and clusters of galaxies can be understood in terms of nonNewtonian gravitational interactions with a relativistic structure compatible with the Einstein Equivalence Principle. This result is derived on very general grounds without knowing the underlying structure of the gravitational field equations. As such, any developed gravitational theory built to deal with these astrophysical scales needs to reproduce the obtained results of this article. |
Address |
[Mendoza, S.] Univ Nacl Autonoma Mexico, Inst Astron, Mexico City 04510, DF, Mexico, Email: sergio@astro.unam.mx; |
Corporate Author |
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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 |
0004-640x |
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 |
WOS:000354392900038 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2234 |
Permanent link to this record |