Records |
Author |
Bridges, M.; Cranmer, K.; Feroz, F.; Hobson, M.; Ruiz de Austri, R.; Trotta, R. |
Title |
A coverage study of the CMSSM based on ATLAS sensitivity using fast neural networks techniques |
Type |
Journal Article |
Year |
2011 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
03 |
Issue |
3 |
Pages |
012 - 23pp |
Keywords |
Supersymmetry; Phenomenology |
Abstract |
We assess the coverage properties of confidence and credible intervals on the CMSSM parameter space inferred from a Bayesian posterior and the profile likelihood based on an ATLAS sensitivity study. In order to make those calculations feasible, we introduce a new method based on neural networks to approximate the mapping between CMSSM parameters and weak-scale particle masses. Our method reduces the computational effort needed to sample the CMSSM parameter space by a factor of similar to 10(4) with respect to conventional techniques. We find that both the Bayesian posterior and the profile likelihood intervals can significantly over-cover and identify the origin of this effect to physical boundaries in the parameter space. Finally, we point out that the effects intrinsic to the statistical procedure are conflated with simplifications to the likelihood functions from the experiments themselves. |
Address |
[Bridges, Michael; Feroz, Farhan; Hobson, Mike] Univ Cambridge, Cavendish Lab, Astrophys Grp, Cambridge CB3 0HE, England, Email: mb435@mrao.cam.ac.uk |
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 |
1126-6708 |
ISBN |
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Conference |
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Notes ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
ISI:000289295200012 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
610 |
Permanent link to this record |
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Author |
Nieves, J.; Ruiz Simo, I.; Vicente Vacas, M.J. |
Title |
Inclusive charged-current neutrino-nucleus reactions |
Type |
Journal Article |
Year |
2011 |
Publication |
Physical Review C |
Abbreviated Journal |
Phys. Rev. C |
Volume |
83 |
Issue |
4 |
Pages |
045501 - 19pp |
Keywords |
|
Abstract |
We present a model for weak charged-current induced nuclear reactions at energies of interest for current and future neutrino oscillation experiments. This model is a natural extension of the work in Refs. [1,2], where the quasielastic contribution to the inclusive electron and neutrino scattering on nuclei was analyzed. The model is based on a systematic many-body expansion of the gauge boson absorption modes that includes one, two, and even three-body mechanisms, as well as the excitation of Delta isobars. The whole scheme has no free parameters, besides those previously adjusted to the weak pion production off the nucleon cross sections in the deuteron, since all nuclear effects were set up in previous studies of photon, electron, and pion interactions with nuclei. We have discussed at length the recent charged-current quasielastic MiniBooNE cross section data, and showed that two-nucleon knockout mechanisms are essential to describing these measurements. |
Address |
[Nieves, J.] Univ Valencia, CSIC, Inst Invest Paterna, Inst Fis Corpuscular IFIC,Ctr Mixto, E-46071 Valencia, Spain |
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 ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
ISI:000289192700004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ pastor @ |
Serial |
594 |
Permanent link to this record |
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Author |
Chang, Q.; Li, X.Q.; Yang, Y.D. |
Title |
The effects of a family nonuniversal Z ' boson on B -> pi pi decays |
Type |
Journal Article |
Year |
2011 |
Publication |
International Journal of Modern Physics A |
Abbreviated Journal |
Int. J. Mod. Phys. A |
Volume |
26 |
Issue |
7-8 |
Pages |
1273-1294 |
Keywords |
B-physics; rare decays; beyond Standard Model |
Abstract |
Motivated by the measured large branching ratio of (B) over bar (0) --> pi(0)pi(0) (the so-called pi pi puzzle), we investigate the effects of a family nonuniversal Z' model on the tree-dominated B --> pi pi decays. We find that the Z' coupling parameter zeta(LR)(d) similar to 0.05 with a nontrivial new weak phase phi(L)(d) similar to -50 degrees, which is relevant to the Z' contributions to the QCD penguin sector Delta C-5, is needed to reconcile the observed discrepancy. Combined with the recent fitting results from B --> pi K, pi K* and rho K decays, the Z' parameter spaces are severely reduced but still not excluded entirely, implying that both the “pi pi” and “pi K” puzzles could be accommodated simultaneously within such a family nonuniversal Z' model. |
Address |
[Chang, Qin; Li, Xin-Qiang] Henan Normal Univ, Dept Phys, Xinxiang 453007, Henan, Peoples R China, Email: changqin@htu.cn |
Corporate Author |
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Thesis |
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Publisher |
World Scientific Publ Co Pte 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 |
0217-751x |
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 ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
ISI:000289175800004 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
595 |
Permanent link to this record |
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Author |
BABAR Collaboration (del Amo Sanchez, P. et al); Lopez-March, N.; Martinez-Vidal, F.; Oyanguren, A. |
Title |
Analysis of the D+ -> K- pi(+) e(+) nu(e) decay channel |
Type |
Journal Article |
Year |
2011 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
Volume |
83 |
Issue |
7 |
Pages |
072001 - 35pp |
Keywords |
|
Abstract |
Using 347: 5 fb(-1) of data recorded by the BABAR detector at the PEP-II electron-positron collider, 244 x 10(3) signal events for the D+ -> K- pi(+)e(+)nu(e) decay channel are analyzed. This decay mode is dominated by the (K) over bar*(892)(0) contribution. We determine the (K) over bar*(892)(0) parameters: m(K*(892)0) (895.4 +/- 0.2 +/- 0.2) MeV/c(2),Gamma(0)(K*(892)0) (46.5 +/- 0.3 +/- 0.2) MeV/c(2), and the Blatt-Weisskopf parameter r(BW) = 2.1 +/- 0.5 +/- 0.5 (GeV/c)(-1), where the first uncertainty comes from statistics and the second from systematic uncertainties. We also measure the parameters defining the corresponding hadronic form factors at q(2) = 0 (r(V) = V(0)/A(1)(0) = 1.463 +/- 0.031, r(2) = A(2)(0)/A(1)(0) = 0.801 +/- 0.020 +/- 0.020) and the value of the axial-vector pole mass parametrizing the q(2) variation of A(1) and A(2): m(A) (2.63 +/- 0.10 +/- 0.13) GeV/c(2). The S-wave fraction is equal to (5.79 +/- 0.16 +/- 0: 15)%. Other signal components correspond to fractions below 1%. Using the D+ -> K-pi(+)pi(+) channel as a normalization, we measure the D+ semileptonic branching fraction: B(D+ K-pi(+)e(+)nu(e)) (4.00 +/- 0: 03 +/- 0.04 +/- 0.09) x 10(-2), where the third uncertainty comes from external inputs. We then obtain the value of the hadronic form factor A(1) at q(2) 0: A(1)(0) 0.6200 +/- 0.0056 +/- 0.0065 +/- 0.0071. Fixing the P-wave parameters, we measure the phase of the S wave for several values of the K pi mass. These results confirm those obtained with K pi production at small momentum transfer in fixed target experiments. |
Address |
[Sanchez, P. del Amo; Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.] Univ Savoie, Lab Annecy le Vieux Phys Particules LAPP, CNRS, IN2P3, F-74941 Annecy Le Vieux, France |
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 ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
ISI:000289055500002 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
592 |
Permanent link to this record |
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Author |
Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. |
Title |
Search for first harmonic modulation in the right ascension distribution of cosmic rays detected at the Pierre Auger Observatory |
Type |
Journal Article |
Year |
2011 |
Publication |
Astroparticle Physics |
Abbreviated Journal |
Astropart Phys. |
Volume |
34 |
Issue |
8 |
Pages |
627-639 |
Keywords |
Ultra-high energy cosmic rays; Large scale anisotropies; Pierre Auger Observatory |
Abstract |
We present the results of searches for dipolar-type anisotropies in different energy ranges above 2.5 x 10(17) eV with the surface detector array of the Pierre Auger Observatory, reporting on both the phase and the amplitude measurements of the first harmonic modulation in the right-ascension distribution. Upper limits on the amplitudes are obtained, which provide the most stringent bounds at present, being below 2% at 99% C.L. for EeV energies. We also compare our results to those of previous experiments as well as with some theoretical expectations. |
Address |
[Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Santos, E.; Tome, B.] LIP, P-1000 Lisbon, Portugal |
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 |
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 ![sorted by Notes field, descending order (down)](img/sort_desc.gif) |
ISI:000288930200007 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
593 |
Permanent link to this record |