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Author |
Mena, O.; Razzaque, S. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Hints of an axion-like particle mixing in the GeV gamma-ray blazar data? |
Type |
Journal Article |
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Year |
2013 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
11 |
Issue |
11 |
Pages |
023 - 12pp |
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Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
axions; active galactic nuclei |
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Abstract |
Axion-Like Particles (ALPs), if exist in nature, are expected to mix with photons in the presence of an external magnetic field. The energy range of photons which undergo strong mixing with ALPs depends on the ALP mass, on its coupling with photons as well as on the external magnetic field and particle density configurations. Recent observations of blazars by the Fermi Gamma-Ray Space Telescope in the 0.1-300 GeV energy range show a break in their spectra in the 1-10 GeV range. We have modeled this spectral feature for the flat-spectrum radio quasar 3C454.3 during its November 2010 outburst, assuming that a significant fraction of the gamma rays convert to ALPs in the large scale jet of this blazar. Using theoretically motivated models for the magnetic field and particle density con figurations in the kiloparsec scale jet, outside the broad-line region, we find an ALP mass m(a) similar to (1 – 3).10(-7) eV and coupling g(a gamma) similar to (1 – 3).10(-10) GeV-1 after performing an illustrative statistical analysis of spectral data in four different epochs of emission. The precise values of m(a) and g(a gamma) depend weakly on the assumed particle density con figuration and are consistent with the current experimental bounds on these quantities. We apply this method and ALP parameters found from fitting 3C454.3 data to another flat-spectrum radio quasar PKS1222+216 (4C+21.35) data up to 400 GeV, as a consistency check, and found good fit. We find that the ALP-photon mixing effect on the GeV spectra may not be washed out for any reasonable estimate of the magnetic field in the intergalactic media. |
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Address |
[Mena, Olga] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: omena@ific.uv.es; |
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Publisher |
Iop Publishing Ltd |
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English |
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Edition |
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ISSN |
1475-7516 |
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Expedition |
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Conference |
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Notes |
WOS:000327843900024 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
1673 |
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Author |
BABAR Collaboration (Lees, J.P. et al); Martinez-Vidal, F.; Oyanguren, A.; Villanueva-Perez, P. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Time-integrated luminosity recorded by the BABAR detector at the PEP-II e(+)e(-) collider |
Type |
Journal Article |
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Year |
2013 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
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Volume |
726 |
Issue |
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Pages |
203-213 |
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Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
BABAR; Integrated luminosity; Electron-positron collider; PEP-II |
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Abstract |
We describe a measurement of the time-integrated luminosity of the data collected by the BABAR experiment at the PEP-II asymmetric-energy e(+)e(-) collider at the Upsilon(4S), Upsilon(3S), and Upsilon(2S) resonances and in a continuum region below each resonance. We measure the time-integrated luminosity by counting e(+)e(-)-> e(+)e(-) and (for the Upsilon(4S) only) e(+)e(-)->mu(+)mu(-) candidate events, allowing additional photons in the final state. We use data-corrected simulation to determine the cross-sections and reconstruction efficiencies for these processes, as well as the major backgrounds. Due to the large cross-sections of e(+)e(-)-> e(+)e(-) and e(+)e(-)->mu(+)mu(-), the statistical uncertainties of the measurement are substantially smaller than the systematic uncertainties. The dominant systematic uncertainties are due to observed differences between data and simulation, as well as uncertainties on the cross-sections. For data collected on the Upsilon(3S) and Upsilon(2S) resonances, an additional uncertainty arises due to Upsilon -> e(+)e(-)X background. For data collected off the Upsilon resonances, we estimate an additional uncertainty due to time dependent efficiency variations, which can affect the short off-resonance runs. The relative uncertainties on the luminosities of the on-resonance (off-resonance) samples are 0.43% (0.43%) for the Upsilon(4S), 0.58% (0.72%) for the Upsilon(3S), and 0.68% (0.88%) for the Upsilon(2S). |
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Address |
[Lees, J. P.; Poireau, V.; Tisserand, V.; Bettoni, D.; Bozzi, C.; Piemontese, L.; Santoro, V.; Passaggio, S.; Robutti, E.; Neri, N.; Morandin, M.; Posocco, M.; Rotondo, M.; Simi, G.; Perez, A.; Walsh, J.; Anulli, E.; Ferrarotto, F.; Gioi, L. Li; Mazzoni, M. A.; Piredda, G.] Univ Savoie, CNRS IN2P3, LAPP, F-74941 A Le Vieux, France, Email: abi@slac.stanford.edu |
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Publisher |
Elsevier Science Bv |
Place of Publication |
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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 |
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Conference |
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Notes |
WOS:000323557200028 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
1561 |
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Permanent link to this record |
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Author |
Resta-Lopez, J. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
Nonlinear protection of beam delivery systems for multi-TeV linear colliders |
Type |
Journal Article |
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Year |
2013 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
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Volume |
8 |
Issue |
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Pages |
P11010 - 19pp |
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Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Beam Optics; Beam dynamics; Accelerator Subsystems and Technologies; Accelerator modelling and simulations (multi-particle dynamics; single-particle dynamics) |
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Abstract |
The post-linac energy collimation system of future e(+)e(-) multi-TeV linear colliders is designed to fulfil an essential function of protection of the Beam Delivery System (BDS) against miss-steered or errant beams likely generated by failure modes in the main linac. For the case of the Compact Linear Collider (CLIC), the energy collimators are required to withstand the impact of a full bunch train in case of failure. This condition makes the design of the energy collimation system especially challenging, if we take into account the need to dispose of an unprecedented transverse beam energy density per beam of the order of GJ/mm(2), when assuming the nominal CLIC beam parameters at 3 TeV centre-of-mass energy, which translates into an extremely high damage potential of uncontrolled beams. This leads to research activities involving new collimator materials and novel collimation techniques. The increase of the transverse spot size at the collimators using nonlinear magnets is a potential solution to guarantee the survival of the collimators. In this paper we present an alternative nonlinear optics based on a multipole magnet pair for energy collimation. In order to preserve an acceptable luminosity performance, we carefully study the general conditions for self-cancellation of optical aberrations between two multipoles. This nonlinear optics scheme is adapted to the requirements of the post-linac energy collimation system for the CLIC BDS, and its performance is investigated by means of beam tracking simulations. Although applied to the CLIC case, this nonlinear protection system could be adapted to other future colliders. |
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Address |
Univ Valencia, Inst Fis Corpuscular IFIC, Ctr Mixto CSIC, Inst Invest Paterna, Valencia 46071, Spain, Email: resta@ific.uv.es |
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Publisher |
Iop Publishing Ltd |
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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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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1748-0221 |
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Medium |
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Expedition |
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Conference |
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Notes |
WOS:000329193500035 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
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Call Number |
IFIC @ pastor @ |
Serial |
1697 |
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Permanent link to this record |
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Author |
Celis, A.; Jung, M.; Li, X.Q.; Pich, A. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
Sensitivity to charged scalars in B -> D-(*)tau nu(tau) and B -> tau nu(tau) decays |
Type |
Journal Article |
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Year |
2013 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
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Volume |
01 |
Issue |
1 |
Pages |
054 - 27pp |
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Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Beyond Standard Model; B-Physics |
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Abstract |
We analyze the recent experimental evidence for an excess of tau-lepton production in several exclusive semileptonic B-meson decays in the context of two-Higgs-doublet models. These decay modes are sensitive to the exchange of charged scalars and constrain strongly their Yukawa interactions. While the usual Type-II scenario cannot accommodate the recent BaBar data, this is possible within more general models in which the charged-scalar couplings to up-type quarks are not as suppressed. Both the B -> D-(*)tau nu(tau) and the B -> tau nu(tau) data can be fitted within the framework of the Aligned Two-Higgs-Doublet Model, but the resulting parameter ranges are in conflict with the constraints from leptonic charm decays. This could indicate a departure from the family universality of the Yukawa couplings, beyond their characteristic fermion mass dependence. We discuss several new observables that are sensitive to a hypothetical charged-scalar contribution, demonstrating that they are well suited to distinguish between different scenarios of new physics in the scalar sector, and also between this group and models with different Dirac structures; their experimental study would therefore shed light on the relevance of scalar exchanges in semileptonic b -> c tau(-)(nu) over bar (tau) transitions. |
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Address |
[Celis, Alejandro; Li, Xin-Qiang; Pich, Antonio] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: alejandro.celis@ific.uv.es; |
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Thesis |
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Publisher |
Springer |
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English |
Summary Language |
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Series Editor |
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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 |
WOS:000315583200054 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
1368 |
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Permanent link to this record |
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Author |
Hirsch, M.; Lineros, R.A.; Morisi, S.; Palacio, J.; Rojas, N.; Valle, J.W.F. |
![goto web page (via DOI) doi](img/doi.gif)
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Title |
WIMP dark matter as radiative neutrino mass messenger |
Type |
Journal Article |
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Year |
2013 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
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Volume |
10 |
Issue |
10 |
Pages |
149 - 18pp |
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Keywords ![sorted by Keywords field, ascending order (up)](img/sort_asc.gif) |
Beyond Standard Model; Cosmology of Theories beyond the SM; Neutrino Physics |
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Abstract |
The minimal seesaw extension of the Standard SU(3)(c)circle times SU(2)(L)circle times U(1)(Y) Model requires two electroweak singlet fermions in order to accommodate the neutrino oscillation parameters at tree level. Here we consider a next to minimal extension where light neutrino masses are generated radiatively by two electroweak fermions: one singlet and one triplet under SU(2)(L). These should be odd under a parity symmetry and their mixing gives rise to a stable weakly interactive massive particle (WIMP) dark matter candidate. For mass in the GeV-TeV range, it reproduces the correct relic density, and provides an observable signal in nuclear recoil direct detection experiments. The fermion triplet component of the dark matter has gauge interactions, making it also detectable at present and near future collider experiments. |
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Address |
[Hirsch, M.; Lineros, R. A.; Palacio, J.; Valle, J. W. F.] Univ Valencia, Edificio Inst Paterna, CSIC, Inst Fis Corpuscular,AHEP Grp, E-46071 Valencia, Spain, Email: mahirsch@ific.uv.es; |
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Publisher |
Springer |
Place of Publication |
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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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Area |
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Expedition |
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Conference |
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Notes |
WOS:000326047200001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
1623 |
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Permanent link to this record |