| Records |
| Author |
Carbone, C.; Mena, O.; Verde, L. |
| Title |
Cosmological parameters degeneracies and non-Gaussian halo bias |
Type |
Journal Article |
| Year |
2010 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
| Volume |
07 |
Issue |
7 |
Pages |
020 - 17pp |
| Keywords |
power spectrum; redshift surveys; galaxy clusters; cosmological parameters from LSS |
| Abstract |
We study the impact of the cosmological parameters uncertainties on the measurements of primordial non-Gaussianity through the large-scale non-Gaussian halo bias effect. While this is not expected to be an issue for the standard Lambda CDM model, it may not be the case for more general models that modify the large-scale shape of the power spectrum. We consider the so-called local non-Gaussianity model, parametrized by the f(NL) non-Gaussianity parameter which is zero for a Gaussian case, and make forecasts on f(NL) from planned surveys, alone and combined with a Planck CMB prior. In particular, we consider EUCLID- and LSST-like surveys and forecast the correlations among f(NL) and the running of the spectral index alpha(s), the dark energy equation of state w, the effective sound speed of dark energy perturbations c(s)(2), the total mass of massive neutrinos M-nu = Sigma m(nu), and the number of extra relativistic degrees of freedom N-nu(rel). Neglecting CMB information on f(NL) and scales k > 0.03h/Mpc, we find that, if N-nu(rel) is assumed to be known, the uncertainty on cosmological parameters increases the error on f(NL) by 10 to 30% depending on the survey. Thus the f(NL) constraint is remarkable robust to cosmological model uncertainties. On the other hand, if N-nu(rel) is simultaneously constrained from the data, the f(NL) error increases by similar to 80%. Finally, future surveys which provide a large sample of galaxies or galaxy clusters over a volume comparable to the Hubble volume can measure primordial non-Gaussianity of the local form with a marginalized 1-sigma error of the order Delta f(NL) similar to 2 – 5, after combination with CMB priors for the remaining cosmological parameters. These results are competitive with CMB bispectrum constraints achievable with an ideal CMB experiment. |
| Address |
[Carbone, Carmelita] Univ Bologna, Dipartimento Astron, I-40127 Bologna, Italy, Email: carmelita.carbone@unibo.it |
| 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 |
1475-7516 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
ISI:000283573200010 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
347 |
| Permanent link to this record |
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| Author |
Wagner, C.; Verde, L.; Boubekeur, L. |
| Title |
N-body simulations with generic non-Gaussian initial conditions I: power spectrum and halo mass function |
Type |
Journal Article |
| Year |
2010 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
| Volume |
10 |
Issue |
10 |
Pages |
022 - 24pp |
| Keywords |
power spectrum; cosmological simulations; initial conditions and eternal universe; galaxy clusters |
| Abstract |
We address the issue of setting up generic non-Gaussian initial conditions for N-body simulations. We consider inflationary-motivated primordial non-Gaussianity where the perturbations in the Bardeen potential are given by a dominant Gaussian part plus a non-Gaussian part specified by its bispectrum. The approach we explore here is suitable for any bispectrum, i.e. it does not have to be of the so-called separable or factorizable form. The procedure of generating a non-Gaussian field with a given bispectrum (and a given power spectrum for the Gaussian component) is not univocal, and care must be taken so that higher-order corrections do not leave a too large signature on the power spectrum. This is so far a limiting factor of our approach. We then run N-body simulations for the most popular inflationary-motivated non-Gaussian shapes. The halo mass function and the non-linear power spectrum agree with theoretical analytical approximations proposed in the literature, even if they were so far developed and tested only for a particular shape (the local one). We plan to make the simulations outputs available to the community via the non-Gaussian simulations comparison project web site http://icc.ub.edu/similar to liciaverde/NGSCP.html. |
| Address |
[Wagner, Christian; Verde, Licia] Univ Barcelona, ICCUB IEEC, E-08028 Barcelona, Spain, Email: cwagner@icc.ub.edu |
| 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 |
1475-7516 |
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 |
ISI:000283577600013 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ elepoucu @ |
Serial |
339 |
| Permanent link to this record |
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| Author |
Jimenez, R.; Kitching, T.; Pena-Garay, C.; Verde, L. |
| Title |
Can we measure the neutrino mass hierarchy in the sky? |
Type |
Journal Article |
| Year |
2010 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
| Volume |
05 |
Issue |
5 |
Pages |
035 - 14pp |
| Keywords |
cosmological neutrinos; neutrino masses from cosmology; power spectrum; gravitational lensing |
| Abstract |
Cosmological probes are steadily reducing the total neutrino mass window, resulting in constraints on the neutrino-mass degeneracy as the most significant outcome. In this work we explore the discovery potential of cosmological probes to constrain the neutrino hierarchy, and point out some subtleties that could yield spurious claims of detection. This has an important implication for next generation of double beta decay experiments, that will be able to achieve a positive signal in the case of degenerate or inverted hierarchy of Majorana neutrinos. We find that cosmological experiments that nearly cover the whole sky could in principle distinguish the neutrino hierarchy by yielding 'substantial' evidence for one scenario over the another, via precise measurements of the shape of the matter power spectrum from large scale structure and weak gravitational lensing. |
| Address |
[Jimenez, Raul; Verde, Licia] Univ Barcelona, ICREA, E-08028 Barcelona, Spain, Email: raul.jimenez@icc.ub.edu |
| 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 |
1475-7516 |
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 |
ISI:000279490800005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
418 |
| Permanent link to this record |
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| Author |
Pierre Auger Collaboration (Abraham, J. et al); Pastor, S. |
| Title |
Measurement of the energy spectrum of cosmic rays above 10(18) eV using the Pierre Auger Observatory |
Type |
Journal Article |
| Year |
2010 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
685 |
Issue |
4-5 |
Pages |
239-246 |
| Keywords |
Pierre Auger Observatory; Cosmic rays; Energy spectrum |
| Abstract |
We report a measurement of the flux of cosmic rays with unprecedented precision and Statistics using the Pierre Auger Observatory Based on fluorescence observations in coincidence with at least one Surface detector we derive a spectrum for energies above 10(18) eV We also update the previously published energy spectrum obtained with the surface detector array The two spectra are combined addressing the systematic uncertainties and, in particular. the influence of the energy resolution on the spectral shape The spectrum can be described by a broken power law E-gamma with index gamma = 3 3 below the ankle which is measured at log(10)(E-ankle/eV) = 18 6 Above the ankle the spectrum is described by a power law with index 2 6 followed by a flux suppression, above about log(10)(E/eV) = 19 5, detected with high statistical significance. |
| Address |
[Ave, M.; Bluemer, H.; Daumiller, K.; Engel, R.; Garrido, X.; Haungs, A.; Heck, D.; Huege, T.; Keilhauer, B.; Klages, H. O.; Kleinfeller, J.; Mathes, H. J.; Mueller, S.; Oehlschlaeger, J.; Pierog, T.; Roth, M.; Salamida, F.; Schieler, H.; Schroeder, F.; Schuessler, F.; Smida, R.; Ulrich, R.; Unger, M.; Valino, I.] Karlsruhe Inst Technol, Inst Kernphys, Karlsruhe, Germany |
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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 |
|
Medium |
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| Area |
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Expedition |
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Conference |
|
| Notes |
ISI:000275640600003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
480 |
| Permanent link to this record |
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| Author |
ATLAS Collaboration (Aad, G. et al); Amoros, G.; Cabrera Urban, S.; Castillo Gimenez, V.; Costa, M.J.; Escobar, C.; Ferrer, A.; Fuster, J.; Garcia, C.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Kaci, M.; Lacasta, C.; Lacuesta, V.R.; Marti-Garcia, S.; Miñano, M.; Mitsou, V.A.; Moles-Valls, R.; Moreno Llacer, M.; Oliver Garcia, E.; Perez Garcia-Estañ, M.T.; Ros, E.; Salt, J.; Solans, C.A.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valladolid Gallego, E.; Valls Ferrer, J.A.; Villaplana Perez, M.; Vos, M.; Wildauer, A. |
| Title |
Search for high mass dilepton resonances in pp collisions at root s=7 TeV with the ATLAS experiment |
Type |
Journal Article |
| Year |
2011 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
| Volume |
700 |
Issue |
3-4 |
Pages |
163-180 |
| Keywords |
Grand unified theory; Narrow resonance; New gauge boson; Z '; Dilepton; Mass spectrum |
| Abstract |
This Letter presents a search for high mass e(+)e(-) or mu(+)mu(-) resonances in pp collisions at root s = 7 TeV at the LHC. The data were recorded by the ATLAS experiment during 2010 and correspond to a total integrated luminosity of similar to 40 pb(-1). No statistically significant excess above the Standard Model expectation is observed in the search region of dilepton invariant mass above 110 GeV. Upper limits at the 95% confidence level are set on the cross section times branching ratio of Z' resonances decaying to dielectrons and dimuons as a function of the resonance mass. A lower mass limit of 1.048 TeV on the Sequential Standard Model Z' boson is derived, as well as mass limits on Z* and E(6)-motivated Z' models. |
| Address |
[Aad, G; Ahles, F; Beckingham, M; Bernhard, R; Bitenc, U; Bruneliere, R; Caron, S; Carpentieri, C; Christov, A; Dahlhoff, A; Dietrich, J; Eckert, S; Fehling-Kaschek, M; Flechl, M; Glatzer, JJ; Hartert, J; Heldmann, M; Herten, G; Jakobs, K; Ketterer, C; Kollefrath, M; Kononov, AI; Kuehn, S; Lai, S; Landgraf, U; Lohwasser, K; Ludwig, L; Ludwig, J; Lumb, D; Mahboubi, K; Meinhardt, J; Mohr, W; Nilsen, H; Parzefall, U; Bueso, XP; Rammensee, M; Runge, K; Rurikova, Z; Schmidt, E; Schumacher, M; Siegert, F; Stoerig, K; Sundermann, JE; Temming, KK; Thoma, S; Tobias, J; Tsiskaridze, V; Venturi, M; Vivarelli, I; von Radziewski, H; Warsinsky, M; Weiser, C; Werner, M; Wiik, LAM; Winkelmann, S; Xie, S; Zimmermann, S] Univ Freiburg, Fak Math & Phys, Freiburg, Germany |
| 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:000292586400002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
806 |
| Permanent link to this record |
