Records |
Author |
Aguilar, A.C.; Ibañez, D.; Mathieu, V.; Papavassiliou, J. |
Title |
Massless bound-state excitations and the Schwinger mechanism in QCD |
Type |
Journal Article |
Year |
2012 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
85 |
Issue |
1 |
Pages |
014018 - 21pp |
Keywords |
|
Abstract |
The gauge-invariant generation of an effective gluon mass proceeds through the well-known Schwinger mechanism, whose key dynamical ingredient is the nonperturbative formation of longitudinally coupled massless bound-state excitations. These excitations introduce poles in the vertices of the theory, in such a way as to maintain the Slavnov-Taylor identities intact in the presence of massive gluon propagators. In the present work we first focus on the modifications induced to the nonperturbative three-gluon vertex by the inclusion of massless two-gluon bound states into the kernels appearing in its skeleton expansion. Certain general relations between the basic building blocks of these bound states and the gluon mass are then obtained from the Slavnov-Taylor identities and the Schwinger-Dyson equation governing the gluon propagator. The homogeneous Bethe-Salpeter equation determining the wave function of the aforementioned bound state is then derived, under certain simplifying assumptions. It is then shown, through a detailed analytical and numerical study, that this equation admits nontrivial solutions, indicating that the QCD dynamics support indeed the formation of such massless bound states. These solutions are subsequently used, in conjunction with the aforementioned relations, to determine the momentumdependence of the dynamical gluon mass. Finally, further possibilities and open questions are briefly discussed. |
Address |
[Aguilar, A. C.] Fed Univ ABC, CCNH, BR-09210170 Santo Andre, Brazil |
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 |
WOS:000299293600005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
881 |
Permanent link to this record |
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Author |
Bodenstein, S.; Bordes, J.; Dominguez, C.A.; Peñarrocha, J.; Schilcher, K. |
Title |
Bottom-quark mass from finite energy QCD sum rules |
Type |
Journal Article |
Year |
2012 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
85 |
Issue |
3 |
Pages |
034003 - 5pp |
Keywords |
|
Abstract |
Finite energy QCD sum rules involving both inverse-and positive-moment integration kernels are employed to determine the bottom-quark mass. The result obtained in the (MS) over bar scheme at a reference scale of 10 GeV is m (m) over bar (b)(10 GeV) = 3623(9) MeV. This value translates into a scale-invariant mass (m) over bar (b)((m) over bar (b)) = 4171(9) MeV. This result has the lowest total uncertainty of any method, and is less sensitive to a number of systematic uncertainties that affect other QCD sum rule determinations. |
Address |
[Bodenstein, S.; Dominguez, C. A.; Schilcher, K.] Univ Cape Town, Ctr Theoret & Math Phys, ZA-7700 Rondebosch, South Africa |
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 |
WOS:000299938300002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
896 |
Permanent link to this record |
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Author |
Bertone, G.; Cerdeño, D.G.; Fornasa, M.; Pieri, L.; Ruiz de Austri, R.; Trotta, R. |
Title |
Complementarity of indirect and accelerator dark matter searches |
Type |
Journal Article |
Year |
2012 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
85 |
Issue |
5 |
Pages |
055014 - 10pp |
Keywords |
|
Abstract |
Even if supersymmetric particles are found at the Large Hadron Collider (LHC), it will be difficult to prove that they constitute the bulk of the dark matter (DM) in the Universe using LHC data alone. We study the complementarity of LHC and DM indirect searches, working out explicitly the reconstruction of the DM properties for a specific benchmark model in the coannihilation region of a 24-parameters supersymmetric model. Combining mock high-luminosity LHC data with presentday null searches for gamma rays from dwarf galaxies with the Fermi Large Area Telescope, we show that current Fermi Large Area Telescope limits already have the capability of ruling out a spurious wino-like solution which would survive using LHC data only, thus leading to the correct identification of the cosmological solution. We also demonstrate that upcoming Planck constraints on the reionization history will have a similar constraining power and discuss the impact of a possible detection of gamma rays from DM annihilation in the Draco dwarf galaxy with a Cherenkov-Telescope-Array-like experiment. Our results indicate that indirect searches can be strongly complementary to the LHC in identifying the DM particles, even when astrophysical uncertainties are taken into account. |
Address |
[Bertone, G.] Univ Amsterdam, GRAPPA Inst, NL-1090 GL Amsterdam, Netherlands |
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 |
WOS:000301647300005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
948 |
Permanent link to this record |
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Author |
ANTARES Collaboration (Adrian-Martinez, S. et al); Aguilar, J.A.; Bigongiari, C.; Dornic, D.; Emanuele, U.; Gomez-Gonzalez, J.P.; Hernandez-Rey, J.J.; Mangano, S.; Ruiz-Rivas, J.; Salesa, F.; Sanchez-Losa, A.; Toscano, S.; Yepes, H.; Zornoza, J.D.; Zuñiga, J. |
Title |
Search for relativistic magnetic monopoles with the ANTARES neutrino telescope |
Type |
Journal Article |
Year |
2012 |
Publication |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
35 |
Issue |
10 |
Pages |
634-640 |
Keywords |
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Abstract |
Magnetic monopoles are predicted in various unified gauge models and could be produced at intermediate mass scales. Their detection in a neutrino telescope is facilitated by the large amount of light emitted compared to that from muons. This paper reports on a search for upgoing relativistic magnetic monopoles with the ANTARES neutrino telescope using a data set of 116 days of live time taken from December 2007 to December 2008. The one observed event is consistent with the expected atmospheric neutrino and muon background, leading to a 90% C.L. upper limit on the monopole flux between 1.3 x 10-(17) and 8.9 x 10(-17) CM-2 s(-1) sr(-1) for monopoles with velocity beta >= 0.625. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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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 |
0927-6505 |
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:000304220600005 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1020 |
Permanent link to this record |
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Author |
NEXT Collaboration (Alvarez, V. et al); Agramunt, J.; Ball, M.; Bayarri, J.; Carcel, S.; Cervera-Villanueva, A.; Diaz, J.; Ferrario, P.; Gil, A.; Gomez-Cadenas, J.J.; Gonzalez, K.; Liubarsky, I.; Lorca, D.; Martin-Albo, J.; Monrabal, F.; Muñoz Vidal, J.; Nebot-Guinot, M.; Perez, J.; Rodriguez, J.; Serra, L.; Sorel, M.; Yahlali, N. |
Title |
SiPMs coated with TPB: coating protocol and characterization for NEXT |
Type |
Journal Article |
Year |
2012 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
Volume |
7 |
Issue |
|
Pages |
P02010 |
Keywords |
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Abstract |
Silicon photomultipliers (SiPM) are the photon detectors chosen for the tracking read-out in NEXT, a neutrinoless beta beta decay experiment which uses a high pressure gaseous xenon time projection chamber (TPC). The reconstruction of event track and topology in this gaseous detector is a key handle for background rejection. Among the commercially available sensors that can be used for tracking, SiPMs offer important advantages, mainly high gain, ruggedness, cost-effectiveness and radio-purity. Their main drawback, however, is their non sensitivity in the emission spectrum of the xenon scintillation (peak at 175 nm). This is overcome by coating these sensors with the organic wavelength shifter tetraphenyl butadiene (TPB). In this paper we describe the protocol developed for coating the SiPMs with TPB and the measurements performed for characterizing the coatings as well as the performance of the coated sensors in the UV-VUV range. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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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:000303940900076 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1028 |
Permanent link to this record |