Records |
Author |
Hernandez, P.; Kekic, M.; Lopez-Pavon, J. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
N_eff in low-scale seesaw models versus the lightest neutrino mass |
Type |
Journal Article |
Year |
2014 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
90 |
Issue |
6 |
Pages |
065033 - 12pp |
Keywords |
|
Abstract |
We evaluate the contribution to N_eff of the extra sterile states in low-scale type I seesaw models (with three extra sterile states). We explore the full parameter space and find that at least two of the heavy states always reach thermalization in the early Universe, while the third one might not thermalize provided the lightest neutrino mass is below O(10(-3) eV). Constraints from cosmology therefore severely restrict the spectra of heavy states in the range 1 eV-100 MeV. The implications for neutrinoless double beta decay are also discussed. |
Address |
[Hernandez, P.; Kekic, M.] Univ Valencia, IFIC CSIC, E-46071 Valencia, Spain, Email: m.pilar.hernandez@uv.es; |
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:000344108100004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2001 |
Permanent link to this record |
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Author |
Pastore, A.; Davesne, D.; Navarro, J. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Nuclear matter response function with a central plus tensor Landau interaction |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of Physics G |
Abbreviated Journal |
J. Phys. G |
Volume |
41 |
Issue |
5 |
Pages |
055103 - 17pp |
Keywords |
Landau; random phase approximation; phenomenological interactions; tensor |
Abstract |
We present a method to obtain response functions in the random phase approximation (RPA) based on a residual interaction described in terms of Landau parameters with central plus tensor contributions. The response functions keep the explicit momentum dependence of the RPA, in contrast with the traditional Landau approximation. Results for symmetric nuclear matter and pure neutron matter are presented using Landau parameters derived from finite-range interactions, both phenomenological and microscopic. We study the convergence of response functions as the number of Landau parameters is increased. |
Address |
[Pastore, A.; Navarro, J.] Univ Libre Brussels, Inst Astron & Astrophys, B-1050 Brussels, Belgium, Email: apastore@ulb.ac.be |
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 |
0954-3899 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
|
Notes |
WOS:000334662500015 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1750 |
Permanent link to this record |
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Author |
Bernabeu, J.; Botella, F.J.; Nebot, M. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Novel T-Violation observable open to any pair of decay channels at meson factories |
Type |
Journal Article |
Year |
2014 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
728 |
Issue |
|
Pages |
95-98 |
Keywords |
|
Abstract |
Quantum entanglement between the two neutral mesons produced in meson factories has allowed the first indisputable direct observation of Time Reversal Violation in the time evolution of the neutral meson between the two decays. The exceptional meson transitions are directly connected to semileptonic and CP eigenstate decay channels. The possibility of extending the observable asymmetries to more decay channels confronts the problem of the “orthogonality condition”, which can be stated with this tonguetwister: Given a decay channel f, which is the decay channel f' such that the meson state not decaying to f is orthogonal to the meson state not decaying to f? In this Letter we propose an alternative T-Violation asymmetry at meson factories which allows its opening to any pair of decay channels. Instead of searching which is the pair of decay channels associated to the T-reverse meson transition, we build an asymmetry which tags the initial states of both the Reference and the T-reverse meson transitions. This observable filters the appropriate final states by means of two measurable survival probabilities. We discuss the methodology to be followed in the analysis of the new observable and the results expected in specific examples. |
Address |
[Nebot, Miguel] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Spain, Email: Jose.Bernabeu@uv.es; |
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 |
WOS:000330556000017 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
1705 |
Permanent link to this record |
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Author |
Binosi, D.; Ibañez, D.; Papavassiliou, J. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Nonperturbative study of the four gluon vertex |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
09 |
Issue |
9 |
Pages |
059 - 32pp |
Keywords |
Nonperturbative Effects; QCD; Confinement |
Abstract |
In this paper we study the nonperturbative structure of the SU(3) four-gluon vertex in the Landau gauge, concentrating on contributions quadratic in the metric. We employ an approximation scheme where “one-loop” diagrams are computed using fully dressed gluon and ghost propagators, and tree-level vertices. When a suitable kinematical configuration depending on a single momentum scale p is chosen, only two structures emerge: the tree-level four-gluon vertex, and a tensor orthogonal to it. A detailed numerical analysis reveals that the form factor associated with this latter tensor displays a change of sign (zero-crossing) in the deep infrared, and finally diverges logarithmically. The origin of this characteristic behavior is proven to be entirely due to the masslessness of the ghost propagators forming the corresponding ghost-loop diagram, in close analogy to a similar effect established for the three-gluon vertex. However, in the case at hand, and under the approximations employed, this particular divergence does not affect the form factor proportional to the tree-level tensor, which remains finite in the entire range of momenta, and deviates moderately from its naive tree-level value. It turns out that the kinematic configuration chosen is ideal for carrying out lattice simulations, because it eliminates from the connected Green's function all one-particle reducible contributions, projecting out the genuine one-particle irreducible vertex. Motivated by this possibility, we discuss in detail how a hypothetical lattice measurement of this quantity would compare to the results presented here, and the potential interference from an additional tensorial structure, allowed by Bose symmetry, but not encountered within our scheme. |
Address |
[Binosi, D.; Ibanez, D.] European Ctr Theoret Studies Nucl Phys & Related, I-38123 Villazzano, TN, Italy, Email: binosi@ectstar.eu; |
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 |
|
Notes |
WOS:000342215400001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1954 |
Permanent link to this record |
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Author |
n_TOF Collaboration (Lederer, C. et al.); Giubrone, G.; Tain, J.L. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Ni-62(n,gamma) and Ni-63(n,gamma) cross sections measured at the n_TOF facility at CERN |
Type |
Journal Article |
Year |
2014 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
89 |
Issue |
2 |
Pages |
025810 - 11pp |
Keywords |
|
Abstract |
The cross section of the Ni-62(n,gamma) reaction was measured with the time-of-flight technique at the neutron time-of-flight facility nTOF at CERN. Capture kernels of 42 resonances were analyzed up to 200 keV neutron energy and Maxwellian averaged cross sections (MACS) from kT = 5-100 keV were calculated. With a total uncertainty of 4.5%, the stellar cross section is in excellent agreement with the the KADoNiS compilation at kT = 30 keV, while being systematically lower up to a factor of 1.6 at higher stellar temperatures. The cross section of the Ni-63(n,gamma) reaction was measured for the first time at nTOF. We determined unresolved cross sections from 10 to 270 keV with a systematic uncertainty of 17%. These results provide fundamental constraints on s-process production of heavier species, especially the production of Cu in massive stars, which serve as the dominant source of Cu in the solar system. |
Address |
[Lederer, C.; Wallner, A.; Pavlik, A.] Univ Vienna, Fac Phys, A-1010 Vienna, Austria, Email: claudia.lederer@ph.ed.uk |
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 |
0556-2813 |
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:000332175500012 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1717 |
Permanent link to this record |
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Author |
Campanario, F.; Kerner, M.; Ninh, D.L.; Zeppenfeld, D. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Next-to-leading order QCD corrections to ZZ production in association with two jets |
Type |
Journal Article |
Year |
2014 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
07 |
Issue |
7 |
Pages |
148 - 14pp |
Keywords |
NLO Computations; Hadronic Colliders |
Abstract |
We present a calculation of next-to-leading order QCD corrections to QCD-induced ZZ production in association with two jets at hadron colliders. Both Z bosons decay leptonically with all off-shell effects, virtual photon contributions and spin-correlation effects fully taken into account. This process is an important background to weak boson scattering and to searches for signals of new physics beyond the Standard Model. As expected, the next-to-leading order corrections reduce significantly the scale uncertainty and show a non-trivial phase space dependence in kinematic distributions. Our code will be publicly available as part of the parton level Monte Carlo program VBFNLO. |
Address |
[Campanario, Francisco] Univ Valencia, CSIC, Div Theory, IFIC, E-46980 Valencia, Spain, Email: francisco.campanario@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:000340051900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1882 |
Permanent link to this record |
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Author |
Campanario, F.; Kerner, M.; Ninh, L.D.; Zeppenfeld, D. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Next-to-leading order QCD corrections to Wgamma production in association with two jets |
Type |
Journal Article |
Year |
2014 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
Volume |
74 |
Issue |
5 |
Pages |
2882 - 9pp |
Keywords |
|
Abstract |
The QCD-induced production channels in association with two jets are computed at next-to-leading order QCD accuracy. The W bosons decay leptonically and full off-shell and finite width effects as well as spin correlations are taken into account. These processes are important backgrounds to beyond Standard Model physics searches and also relevant to test the nature of the quartic gauge couplings of the Standard Model. The next-to-leading order corrections reduce the scale uncertainty significantly and show a non-trivial phase space dependence. Our code will be publicly available as part of the parton level Monte Carlo program VBFNLO. |
Address |
[Campanario, Francisco] Univ Valencia, CSIC, IFIC, Div Theory, Valencia 46980, Spain, Email: francisco.campanario@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 |
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 |
WOS:000340092900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1888 |
Permanent link to this record |
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Author |
Campanario, F.; Kerner, M.; Ninh, L.D.; Zeppenfeld, D. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Next-to-leading order QCD corrections to W+W+ and W-W- production in association with two jets |
Type |
Journal Article |
Year |
2014 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
89 |
Issue |
5 |
Pages |
054009 - 11pp |
Keywords |
|
Abstract |
We present a study of W+W+ jj and W-W-jj production including leptonic decays in hadron-hadron collisions. The full electroweak and QCD induced contributions and their interferences are calculated at leading order. We find that, for inclusive cuts, the interference effects can be large if the jets are produced with large transverse momentum where, however, the production rate is suppressed. We also discuss the vector-boson-fusion cuts and show the validity of the vector-boson-fusion approximation. The next-to-leading order QCD corrections to the QCD-induced channels are also calculated. Compared to the previous calculation, we allow the intermediate W bosons to be off shell. For on-shell W production, we obtain an excellent agreement with previous results. Our code will be publicly available as part of the parton level Monte Carlo program VBFLNO. |
Address |
[Campanario, Francisco] Univ Valencia, CSIC, Theory Div, IFIC, E-46980 Valencia, Spain, Email: francisco.campanario@ific.uv.es; |
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:000333103700004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1740 |
Permanent link to this record |
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Author |
Aguilar, A.C.; Binosi, D.; Ibañez, D.; Papavassiliou, J. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
New method for determining the quark-gluon vertex |
Type |
Journal Article |
Year |
2014 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
90 |
Issue |
6 |
Pages |
065027 - 26pp |
Keywords |
|
Abstract |
We present a novel nonperturbative approach for calculating the form factors of the quark-gluon vertex in terms of an unknown three-point function, in the Landau gauge. The key ingredient of this method is the exact all-order relation connecting the conventional quark-gluon vertex with the corresponding vertex of the background field method, which is Abelian-like. When this latter relation is combined with the standard gauge technique, supplemented by a crucial set of transverse Ward identities, it allows the approximate determination of the nonperturbative behavior of all 12 form factors comprising the quark-gluon vertex, for arbitrary values of the momenta. The actual implementation of this procedure is carried out in the Landau gauge, in order to make contact with the results of lattice simulations performed in this particular gauge. The most demanding technical aspect involves the approximate calculation of the components of the aforementioned (fully dressed) three-point function, using lattice data as input for the gluon propagators appearing in its diagrammatic expansion. The numerical evaluation of the relevant form factors in three special kinematical configurations (soft-gluon and quark symmetric limit, zero quark momentum) is carried out in detail, finding qualitative agreement with the available lattice data. Most notably, a concrete mechanism is proposed for explaining the puzzling divergence of one of these form factors observed in lattice simulations. |
Address |
[Aguilar, A. C.] Univ Estadual Campinas, UNICAMP, Inst Phys Gleb Wataghin, BR-13083859 Sao Paulo, 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:000342147700012 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1932 |
Permanent link to this record |
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Author |
Agramunt, J. et al; Algora, A.; Domingo-Pardo, C.; Jordan, D.; Rubio, B.; Tain, J.L.; Valencia, E. |
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
New Beta-delayed Neutron Measurements in the Light-mass Fission Group |
Type |
Journal Article |
Year |
2014 |
Publication |
Nuclear Data Sheets |
Abbreviated Journal |
Nucl. Data Sheets |
Volume |
120 |
Issue |
|
Pages |
74-77 |
Keywords |
|
Abstract |
A new accurate determination of beta-delayed neutron emission probabilities from nuclei in the low mass region of the light fission group has been performed. The measurements were carried out using the BELEN 4 pi neutron counter at the IGISOL-JYFL mass separator in combination with a Penning trap. The new results significantly improve the uncertainties of neutron emission probabilities for Br-91, As-86, As-85, and Ge-85 nuclei. |
Address |
[Agramunt, J.; Algora, A.; Domingo-Pardo, C.; Jordan, D.; Rubio, B.; Tain, J. L.; Valencia, E.] Univ Valencia, CSIC, Inst Fis Corpuscular, E-46071 Valencia, Spain, Email: tain@ific.uv.es |
Corporate Author |
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Thesis |
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Publisher |
Academic Press Inc Elsevier Science |
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 |
0090-3752 |
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:000339860100020 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
1871 |
Permanent link to this record |