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103 results on '"Francesc Ferrer"'

1. Imprints of a supercooled phase transition in the gravitational wave spectrum from a cosmic string network

Author

Francesc Ferrer, Anish Ghoshal, and Marek Lewicki

Subjects
Cosmology of Theories BSM, Early Universe Particle Physics, Phase Transitions in the Early Universe, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

Abstract A network of cosmic strings (CS), if present, would continue emitting gravitational waves (GW) as it evolves throughout the history of the Universe. This results in a characteristic broad spectrum making it a perfect source to infer the expansion history. In particular, a short inflationary period caused by a supercooled phase transition would cause a drop in the spectrum at frequencies corresponding to that event. However, the impact on the spectrum is similar to the ones caused by an early matter-dominated era or from particle production, making it difficult to disentangle these different physical origins. We point out that, in the case of a short inflationary period, the GW spectrum receives an additional contribution from the phase transition itself. This leads to a characteristic imprint of a peak on top of a wide plateau both visible at future GW observatories.

Published
2023
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4. Combined simulation and optimization framework for irrigation scheduling in agriculture fields

Author

Gema Rodrigo, Daniel Fernàndez-Garcia, Mireia Fontanet, Francesc Ferrer, Josep Maria Villar, Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, and Universitat Politècnica de Catalunya. GHS - Grup d'Hidrologia Subterrània

Subjects
0106 biological sciences, Irrigation -- Management -- Mathematical models, Irrigation, 0208 environmental biotechnology, Soil Science, Growing season, Context (language use), 02 engineering and technology, Agricultural engineering, 01 natural sciences, Water scarcity, Regatge -- Optimització matemàtica, Enginyeria civil::Enginyeria hidràulica, marítima i sanitària::Canals i regadius [Àrees temàtiques de la UPC], Water content, Water Science and Technology, business.industry, Crop yield, Irrigation scheduling, 04 agricultural and veterinary sciences, 020801 environmental engineering, Agriculture, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Environmental science, business, Agronomy and Crop Science, 010606 plant biology & botany
Abstract

In the context of growing evidence of climate change and the fact that agriculture uses about 70% of all the water available for irrigation in semi-arid areas, there is an increasing probability of water scarcity scenarios. Water irrigation optimization is, therefore, one of the main goals of researchers and stakeholders involved in irrigated agriculture. Irrigation scheduling is often conducted based on simple water requirement calculations without accounting for the strong link between water movement in the root zone, soil–water–crop productivity and irrigation expenses. In this work, we present a combined simulation and optimization framework aimed at estimating irrigation parameters that maximize the crop net margin. The simulation component couples the movement of water in a variably saturated porous media driven by irrigation with crop water uptake and crop yields. The optimization component assures maximum gain with minimum cost of crop production during a growing season. An application of the method demonstrates that an optimal solution exists and substantially differs from traditional methods. In contrast to traditional methods, results show that the optimal irrigation scheduling solution prevents water logging and provides a more constant value of water content during the entire growing season within the root zone. As a result, in this case, the crop net margin cost exhibits a substantial increase with respect to the traditional method. The optimal irrigation scheduling solution is also shown to strongly depend on the particular soil hydraulic properties of the given field site. We thank to our colleagues from Aigües Segarra Garrigues (ASG) company for sharing some of the data necessary to conduct this work and also to Doctorats Industrials to fund the project where this work is involved.

Published
2021
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6. Fast radio bursts from axion stars moving through pulsar magnetospheres

Author

Fa Peng Huang, Francesc Ferrer, P. S. Bhupal Dev, and James Buckley

Subjects
Photon, Physics::Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Magnetosphere, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, symbols.namesake, High Energy Physics::Theory, High Energy Physics - Phenomenology (hep-ph), Pulsar, 0103 physical sciences, 010306 general physics, Axion, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Redshift, Neutron star, Stars, High Energy Physics - Phenomenology, symbols, Astrophysics - High Energy Astrophysical Phenomena, Doppler effect
Abstract

We study the radio signals generated when an axion star enters the magnetosphere of a neutron star. As the axion star moves through the resonant region where the plasma-induced photon mass becomes equal to the axion mass, the axions can efficiently convert into photons, giving rise to an intense, transient radio signal. We show that a dense axion star with a mass $\sim 10^{-13}M_{\odot}$ composed of $\sim 10\: \mu$eV axions can account for most of the mysterious fast radio bursts., Comment: Published version in Phys. Rev. D, 6 pages, 2 figures

Published
2020

7. Impacte de la COVID-19 a les entitats de Barcelona : informe 2a enquesta

Author

Torre Jussana-Centre de Serveis a les Associacions, Fundació Francesc Ferrer i Guàrdia, Mañé, Josep, Panadero Hernández, Hungría, Alonso, Oriol, Torre Jussana-Centre de Serveis a les Associacions, Fundació Francesc Ferrer i Guàrdia, Mañé, Josep, Panadero Hernández, Hungría, and Alonso, Oriol

Abstract

Informe elaborat en el context de desconfinament davant l’emergència provocada per la COVID-19., Report prepared in the context of deconfinement to the emergency caused by COVID-19., Informe elaborado en el contexto de desconfinamiento ante la emergencia provocada por la COVID-19.

Published
2021

9. El Panoràmic 2019 : l'economia de les associacions catalanes : recerca qualitativa

Author

Torre Jussana-Centre de Serveis a les Associacions, Consell d'Associacions de Barcelona, Observatori del Tercer Sector, Fundació Pere Tarrés, Fundació Francesc Ferrer i Guàrdia, Fundació la Caixa, Cendrós, Eloi, and Panadero Hernández, Hungría

Subjects
Associationism, Asociacionismo, Societat i benestar, Economia, Associacionisme, enquestes
Abstract

En aquesta edició l’anàlisi se centra en l'economia de les associacions i entitats catalanes

Published
2020

10. Magnetic field production at a first-order electroweak phase transition

Author

Yiyang Zhang, Tanmay Vachaspati, and Francesc Ferrer

Subjects
Physics, Phase transition, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Condensed matter physics, Magnetic energy, 010308 nuclear & particles physics, Electroweak interaction, High Energy Physics::Phenomenology, Equations of motion, FOS: Physical sciences, 01 natural sciences, Magnetic field, Higgs field, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), 0103 physical sciences, Higgs boson, 010306 general physics, False vacuum, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We study the generation of magnetic field seeds during a first-order electroweak phase transition, by numerically evolving the classical equations of motion of the bosonic electroweak theory on the lattice. The onset of the transition is implemented by the random nucleation of bubbles with an arbitrarily oriented Higgs field in the broken phase. We find that about 10% of the latent heat is converted into magnetic energy, with most of the magnetic fields being generated in the last stage of the phase transition when the Higgs oscillates around the true vacuum. The energy spectrum of the magnetic field has a peak that shifts towards larger length scales as the phase transition unfolds. By the end of our runs the peak wavelength is of the order of the bubble percolation scale, or about a third of our lattice size., 12 pages, 13 figures

Published
2019

11. El Panoràmic 2019

Author

Torre Jussana-Centre de Serveis a les Associacions, Consell d'Associacions de Barcelona, Observatori del Tercer Sector, Fundació Pere Tarrés, Fundació Francesc Ferrer i Guàrdia, Fundació la Caixa, Cendrós, Eloi, Panadero Hernández, Hungría, Torre Jussana-Centre de Serveis a les Associacions, Consell d'Associacions de Barcelona, Observatori del Tercer Sector, Fundació Pere Tarrés, Fundació Francesc Ferrer i Guàrdia, Fundació la Caixa, Cendrós, Eloi, and Panadero Hernández, Hungría

Abstract

En aquesta edició l’anàlisi se centra en l'economia de les associacions i entitats catalanes

Published
2020

12. Gravitational Waves from First-Order Phase Transition in a Simple Axion-Like Particle Model

Author

Yiyang Zhang, Yongchao Zhang, Francesc Ferrer, and P. S. Bhupal Dev

Subjects
Physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), 010308 nuclear & particles physics, Gravitational wave, FOS: Physical sciences, Astronomy and Astrophysics, Parameter space, 01 natural sciences, Symmetry (physics), Standard Model, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), Quantum electrodynamics, 0103 physical sciences, Higgs boson, Symmetry breaking, Scalar field, Axion, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We consider a gauge-singlet complex scalar field $\Phi$ with a global $U(1)$ symmetry that is spontaneously broken at some high energy scale $f_a$. As a result, the angular part of the $\Phi$-field becomes an axion-like particle (ALP). We show that if the $\Phi$-field has a non-zero coupling $\kappa$ to the Standard Model Higgs boson, there exists a certain region in the $\left(f_a, \kappa\right)$ parameter space where the global $U(1)$ symmetry-breaking induces a strongly first order phase transition, thereby producing stochastic gravitational waves that are potentially observable in current and future gravitational-wave detectors. In particular, we find that future gravitational-wave experiments such as TianQin, BBO and Cosmic Explorer could probe a broad range of the energy scale $10^3 \, {\rm GeV} \lesssim f_a \lesssim 10^{8} \, {\rm GeV}$, independent of the ALP mass. Since all the ALP couplings to the Standard Model particles are proportional to inverse powers of the energy scale $f_a$ (up to model-dependent ${\cal O}(1)$ coefficients), the gravitational-wave detection prospects are largely complementary to the current laboratory, astrophysical and cosmological probes of the ALP scenarios., Comment: 30 pages, 11 figures, minor changes, version accepted by JCAP

Published
2019
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13. Partitioning evapotranspiration of a drip-irrigated wheat crop : inter-comparing eddy covariance-, sap flow-, lysimeter- and FAO-based methods

Author

Vincent Simonneaux, Jamal Ezzahar, Patrick Mordelet, Said Khabba, Bouchra Ait Hssaine, Olivier Merlin, Salah Er-Raki, Luis Enrique Olivera-Guerra, francesc ferrer, Valérie Le Dantec, Zoubair Rafi, Abdelhakim Amazirh, Université Cadi Ayyad [Marrakech] (UCA), Centre d'études spatiales de la biosphère (CESBIO), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)

Subjects
0106 biological sciences, Atmospheric Science, 010504 meteorology & atmospheric sciences, Lysimeter, Eddy covariance, Soil science, 01 natural sciences, Evapotranspiration, Sap flow, [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, Irrigation management, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Water content, ComputingMilieux_MISCELLANEOUS, Evaporation-transpiration, 0105 earth and related environmental sciences, Transpiration, Mathematics, 2. Zero hunger, FAO-56, Global and Planetary Change, Eddy correlation, Forestry, 15. Life on land, Wheat, Measurement uncertainty, Stage (hydrology), Agronomy and Crop Science, 010606 plant biology & botany
Abstract

A precise estimate of the evapotranspiration (ET) partitioning is fundamental for determining the crop water needs and optimizing irrigation management. The plant transpiration (T) is generally considered to be the most desirable component, while reducing the soil evaporation (E) could be one of the most important water-saving actions in semi-arid agricultural regions. Given the lack of reference method to estimate the E/T partitioning of wheat crop, this study inter-compares four different methods based on eddy covariance, sap flow and lysimetry measurements and FAO modeling. The objectives are: i) to quantify the systematic and random uncertainty in E and T observations, ii) to evaluate the partitioning ratio (T/ET) at the daily/field scale and iii) to assess the performance of the FAO model over two drip irrigated wheat fields. Results indicate that despite the small surface sensed by mini-lysimeters, the partitioning ratio is evaluated more precisely (19% relative error) with lysimetry than with the other systems (any combination of eddy covariance, lysimetry and sap flow measurements). Moreover, stem-scale T measurements from sap flow sensors are subject to representativeness issues at the field scale, and to systematic errors during water-stress and senescence periods. The lysimeter-derived partitioning ratio increases from about 0.50 to 0.85 during the growth stage and rapidly drops towards 0 during senescence. Its dynamics is found to be significantly correlated (R>0.7) with the 5-cm soil moisture. By comparing FAO simulations with observations, it is found that the FAO method overestimates T and underestimates E, while keeping satisfying ET estimates for drip irrigated wheat. This study suggests that different independent measurement techniques should be implemented to both quantify and reduce uncertainties in the T/ET ratio, and that accurate observations are still needed to improve the modeling of E/T components.

Published
2019
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14. Morning crop water stress index as a sensitive indicator of water status in apple trees

Author

Colin S. Campbell, Francesc Ferrer-Alegre, Abdelmoneim Zakaria Mohamed, Troy Peters, Travis Bates, and Yasin Osroosh

Subjects
Crop water stress index, Animal science, Water potential, Linear relationship, Soil water, Soil water deficit, DNS root zone, Environmental science, Noon, Morning
Abstract

We compared the theoretical crop water stress index (CWSI) averaged over late morning hours (10:00-11:00 AM), (CWSImo) and over solar noon hours, midday (1:00-3:00 PM), (CWSImd). We assessed their sensitivity to changes in soil water content including soil water deficit, (SWD, %) and soil matric potential, (SMP, kPa) at different root zone depths, and to stem water potential (Ψstem). At the effective root zone depth, the linear relationship between SWD and CWSI averaged over morning hours resulted in a reasonably good correlation (R2 = 0.52, p

Published
2019
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15. Pla d'actuació del Parc de Montjuïc : Propostes oficials

Author

Regidoria de Participació i Districtes, Gerència de Drets de Ciutadania, Participació i Transparència, Fundació Francesc Ferrer i Guàrdia, and 300.000 km/s (Firma)

Subjects
Public spaces, Espais públics, informes altres, Societat i benestar, Participació ciutadana, Participación ciudadana, Citizen participation, Espacios públicos
Published
2019

16. Greenhouse gas calculator at farm level addressed to the growers

Author

Francesc Ferrer, Francesc Castells, Assumpció Antón, and Carmen M. Torres

Subjects
Engineering, 010504 meteorology & atmospheric sciences, business.industry, Environmental engineering, Greenhouse, Agricultural engineering, 010501 environmental sciences, 01 natural sciences, Product life-cycle management, Data quality, Greenhouse gas, Carbon footprint, Production (economics), business, Life-cycle assessment, Uncertainty analysis, 0105 earth and related environmental sciences, General Environmental Science
Abstract

When assessing agricultural products using life cycle assessment (LCA), the farmers play a key role as they have first-hand information to understanding the activities involved in the assessed systems. However, the compilation of these data can be tiresome and complicated. To engage farmers in the LCA, a web tool (eFoodPrint Env®) was designed to facilitate their tasks as much as possible, seeking the trade-off between comprehensiveness and time consumption without affecting the quality. The model relies on primary data for the specific parcel and growing season; it starts with the ancillary materials extraction and ends with the transport of products to the corresponding cooperative. The model excludes the infrastructure except in the cases of protected crops including greenhouses. To build the inventory, the web tool guides the user through a questionnaire divided in cultivation, machinery, fertilization, plant treatment, and transport. Carbon footprint is computed with global warming potentials of the International Panel of Climate Change following the norm PAS2050. The calculations behind the web tool have the following modules: (1) farming input and output flows; (2) database and default data; (3) greenhouse infrastructure; (4) impact assessment; (5) uncertainty analysis, and (6) results module. The web tool is already in use and can be applied to most of agricultural facilities. Examples of estates of corn, nectarine, grape, and tomato are herein showed. The application displays the results distributed in the different stages considered in each product system, and the scores include error bars derived from the uncertainty analysis. Corn production showed the highest carbon footprint per kilogram of product, with a high contribution due to fertilizer production and application. The carbon footprint of tomato production in low-tunnel greenhouse showed nearly 30 % of impact related only to the greenhouse structure. Regarding uncertainty, the worst value is also associated to the corn production for which the most uncertain activities have more influence (fertilizer and transport). The design of the tool has the objective of meeting the requirements of data quality and comprehensiveness with the reality of the farms. The tool is generic enough to be applied to different cropping systems, enabling the generation of simple reports with the results of the analysis. The modular structures of both data entry and model calculation allow the identification of potential sources of uncertainty and hotspots within the studied life cycle stages.

Published
2016
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17. El panoràmic 2018

Author

Torre Jussana-Centre de Serveis a les Associacions, Consell d'Associacions de Barcelona, Observatori del Tercer Sector, Fundació Pere Tarrés, Fundació Francesc Ferrer i Guàrdia, Fundació la Caixa, Cendrós, Eloi, Panadero Hernández, Hungría, Torre Jussana-Centre de Serveis a les Associacions, Consell d'Associacions de Barcelona, Observatori del Tercer Sector, Fundació Pere Tarrés, Fundació Francesc Ferrer i Guàrdia, Fundació la Caixa, Cendrós, Eloi, and Panadero Hernández, Hungría

Abstract

En aquesta edició l’anàlisi se centra en les característiques de la base social de les entitats catalanes

Published
2019

19. Primordial Black Holes from the QCD axion

Author

Eduard Massó, Giuliano Panico, Francesc Ferrer, Fabrizio Rompineve, and Oriol Pujolàs

Subjects
Quantum chromodynamics, Inflation (cosmology), Physics, Particle physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Physics beyond the Standard Model, Dark matter, High Energy Physics::Phenomenology, General Physics and Astronomy, Primordial black holes, FOS: Physical sciences, Lambda-CDM model, Primordial black hole, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Omega, General Relativity and Quantum Cosmology, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), 0103 physical sciences, Gravitational-wave observatory, 010306 general physics, Axion, Cosmological modeling, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We propose a mechanism to generate Primordial Black Holes (PBHs) which is independent of cosmological inflation and occurs slightly below the QCD phase transition. Our setup relies on the collapse of long-lived string-domain wall networks and is naturally realized in QCD axion models with domain wall number $N_{DW}>1$ and Peccei-Quinn symmetry broken after inflation. In our framework, dark matter is mostly composed of axions in the meV mass range along with a small fraction, $\Omega_{\text{PBH}} \gtrsim 10^{-6} \Omega_{\text{CDM}} $ of heavy $M \sim 10^4-10^7 M_\odot$ PBHs. The latter could play a role in alleviating some of the shortcomings of the $\Lambda$CDM model on sub-galactic scales. The scenario has distinct signatures in ongoing axion searches as well as gravitational wave observatories., Comment: 7 pages, 2 figures. v2: version accepted for publication in PRL

Published
2018
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20. Pla d'Actuació de la Muntanya de Montjuïc : document de diagnosi tècnica

Author

Districte 3. Sants-Montjuïc, Fundació Francesc Ferrer i Guàrdia, and 300.000 km/s (Firma)

Subjects
Convivencia, Urbanisme i infraestructures, Equipaments col·lectius, Animación cultural, Movilidad urbana, Pla d’Actuació del Parc de Montjuïc 2019-2029 (Barcelona), Societat i benestar, Equipamientos colectivos, Ecologia urbana, Sector públic, Tourism, Cultural animation, Zonas verdes, Citizen participation, Urban mobility, Deportes, Esports, Infrastructure (Economics), Pla General Metropolità de Barcelona, Turismo, Mobilitat urbana, Activitats culturals, Open spaces, Urban ecology, monografies, Convivència, Turisme, Participació ciutadana, Participación ciudadana, Zones verdes, Coexistence, Sports, Ecología urbana
Published
2018

21. El panoràmic 2017

Author

Torre Jussana-Centre de Serveis a les Associacions, Consell d'Associacions de Barcelona, Observatori del Tercer Sector, Fundació Pere Tarrés, Fundació Francesc Ferrer i Guàrdia, Fundació la Caixa, Fornies, Albert, Aguilar Mañas, Marina, Torre Jussana-Centre de Serveis a les Associacions, Consell d'Associacions de Barcelona, Observatori del Tercer Sector, Fundació Pere Tarrés, Fundació Francesc Ferrer i Guàrdia, Fundació la Caixa, Fornies, Albert, and Aguilar Mañas, Marina

Published
2018

22. Boletín de la Escuela Moderna

Author

Francesc Ferrer i Guàrdia

Subjects
lcsh:L7-991, lcsh:Education (General)
Abstract

BARCELONA 20 OCTUBRE 1901Si um deber de cortesia obliga a toda nueva publicacion a dirigir un saludo a la prensa, como reconocimiento previo de cierta ineludible solidaridad que entre la mis-ma exite, por efecto de la finalidad comun de objetivo, el Boletin de la Escuela Moder-na, tiene ademas contraida ya una deuda de gratitud.En cumplimiento de este doble deber, saluda a la prensa en general, con la que quiere contribuir a ese conjunto de opinion, a esa condensacion de pensamiento que ha de traducirse en maifestacion de la voluntad popular que por evolucion cada dia mas rapida ha de llegar a los limites racionales que puede alcanzar el progreso; ma-nifiestase agradecido a la condescendencia com que esa misma prensa ha acogido la institucion que venimos a representar, declarando que merced a ella ha alcanzado esta un exito superior al que nos prometian nuestras mas lisonjeras esperanzas.A la prensa profesional, ademas de considerarla comprendida en las manifesta-ciones anteriores, prometemos respeto y confraternidad, sin que las diferencias de crieterio que puedan separarnos sean jamas motivo para variar de linea de conducta.Tenemos personalidad propia, pero estamos exentos de todo egoismo; con esta ingenua declaracion deseamos que se entienda que estamos dispuestos a conceder, no ya en proporcion de lo que se nos otorgue, sino mas bien en relacion de cuanto deseariamos que se nos otorgase. A ello nos obliga el sentimiento altruista a que la Escuela Moderna debe su existencia.

Published
2013

23. Projecte cultural i comunitari del Teatre Arnau : document en construcció

Author

Regidoria de Participació i Districtes, Gerència de Drets de Ciutadania, Participació i Transparència, and Fundació Francesc Ferrer i Guàrdia

Subjects
informes altres, Teatre Arnau (Barcelona), Societat i benestar, Participació ciutadana, Participación ciudadana, Citizen participation
Published
2017

24. Dark matter spikes in the vicinity of Kerr black holes

Author

Francesc Ferrer, Clifford M. Will, Augusto Medeiros da Rosa, Institut d'Astrophysique de Paris (IAP), and Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Cosmology and Nongalactic Astrophysics (astro-ph.CO), geometry, White hole, Astrophysics::High Energy Astrophysical Phenomena, gravitation: effect, halo, FOS: Physical sciences, Primordial black hole, General Relativity and Quantum Cosmology (gr-qc), Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, dark matter: density, angular momentum, 01 natural sciences, rotation, General Relativity and Quantum Cosmology, High Energy Physics - Phenomenology (hep-ph), black hole: Kerr, 0103 physical sciences, Extremal black hole, 010303 astronomy & astrophysics, Physics, black hole: spin, 010308 nuclear & particles physics, dark matter: annihilation, Black hole, High Energy Physics - Phenomenology, Rotating black hole, Intermediate-mass black hole, adiabatic, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], [PHYS.GRQC]Physics [physics]/General Relativity and Quantum Cosmology [gr-qc], Stellar black hole, Spin-flip, galaxy, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The growth of a massive black hole will steepen the cold dark matter density at the center of a galaxy into a dense spike, enhancing the prospects for indirect detection. We study the impact of black hole spin on the density profile using the exact Kerr geometry of the black whole in a fully relativistic adiabatic growth framework. We find that, despite the transfer of angular momentum from the hole to the halo, rotation increases significantly the dark matter density close to the black hole. The gravitational effects are still dominated by the black hole within its influence radius, but the larger dark matter annihilation fluxes might be relevant for indirect detection estimates., Comment: Published version plus corrected typo in Fig 12

Published
2017
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25. Vacuum Topology and the Electroweak Phase Transition

Author

Yiyang Zhang, Tanmay Vachaspati, and Francesc Ferrer

Subjects
High Energy Physics - Theory, Physics, Particle physics, Phase transition, QED vacuum, Cosmology and Nongalactic Astrophysics (astro-ph.CO), 010308 nuclear & particles physics, Numerical analysis, Electroweak interaction, High Energy Physics::Phenomenology, FOS: Physical sciences, Technicolor, Gauge (firearms), Topology, 01 natural sciences, Magnetic field, High Energy Physics - Phenomenology, High Energy Physics::Theory, High Energy Physics - Phenomenology (hep-ph), High Energy Physics - Theory (hep-th), Quantum electrodynamics, 0103 physical sciences, 010306 general physics, Topology (chemistry), Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We investigate if the topology of pure gauge fields in the electroweak vacuum can play a role in classical dynamics at the electroweak phase transition. Our numerical analysis shows that magnetic fields are produced if the initial vacuum has non-trivial Chern-Simons number, and the fields are helical if the Chern-Simons number changes during the phase transition., Comment: 10 pages, 5 figures

Published
2017
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27. Eines i tècniques de dinamització

Author

Gerència de Drets de Ciutadania, Participació i Transparència, Direcció de Serveis de Democràcia Activa i Descentralització, Col·lectiu Punt 6, S.C.C.L., Delibera, Cooperativa ETCS, Everis Spain, S.L., Fundació Desenvolupament Comunitari (Barcelona), Fundació Francesc Ferrer i Guàrdia, Fundació Pere Tarrés, Lacol, Momentum Co, Pla Estel (Firma), Raons Públiques, S.C.C.L., Urbaning (Firma), Barcelona Activa, S.A., Mora Corominas, Arnau, and Lacueva Rueda, Alicia

Subjects
Solución de problemas en grupo, Planificación estratégica, Group dynamicss, Dinàmica de grups, Sector públic, Planificació estratègica, monografies, Programa d'Actuació Municipal (PAM) 2016-2019 (Barcelona), Strategic planning, Participació ciutadana, Participación ciudadana, Citizen participation, Solució de problemes en grup, Group problem solving, Dinámica de grupos
Published
2016

28. Clustering of ultrahigh energy cosmic rays and their sources

Author

Nick Evans, Subir Sarkar, and Francesc Ferrer

Subjects
Physics, Nuclear and High Energy Physics, Cold dark matter, media_common.quotation_subject, Astrophysics::High Energy Astrophysical Phenomena, Dark matter, Astrophysics (astro-ph), Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, FOS: Physical sciences, Cosmic ray, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Correlation function (astronomy), Dark matter halo, Galactic halo, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), Sky, Relic particles, Astrophysics::Galaxy Astrophysics, media_common
Abstract

The sky distribution of cosmic rays with energies above the 'GZK cutoff' holds important clues to their origin. The AGASA data, although consistent with isotropy, shows evidence for small-angle clustering, and it has been argued that such clusters are aligned with BL Lacertae objects, implicating these as sources. It has also been suggested that clusters can arise if the cosmic rays come from the decays of very massive relic particles in the Galactic halo, due to the expected clumping of cold dark matter. We examine these claims and show that both are in fact not justified., 13 pages, 8 figures, version in press at Phys. Rev. D

Published
2016
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29. Reply to 'Comment on 'Clustering of ultrahigh energy cosmic rays and their sources' '

Author

Francesc Ferrer, Subir Sarkar, and Nick Evans

Subjects
Physics, musculoskeletal diseases, Nuclear and High Energy Physics, Correlation function (statistical mechanics), stomatognathic diseases, genetic structures, Cosmic ray, Angular resolution, Ultrahigh energy, sense organs, Cluster analysis, eye diseases, Computational physics
Abstract

We reiterate that there is no evidence that BL Lacs are sources of ultrahigh energy cosmic rays. © 2004 The American Physical Society.

Published
2016
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30. The Anisotropy of the Ultra-High Energy Cosmic Rays

Author

Wyn Evans, Francesc Ferrer, and Subir Sarkar

Subjects
Physics, Supermassive black hole, Astrophysics::High Energy Astrophysical Phenomena, Centaurus A, Dark matter, Astrophysics (astro-ph), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Virgo Cluster, Galaxy, Dark matter halo, Galactic halo, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), Ultra-high-energy cosmic ray, Astrophysics::Galaxy Astrophysics
Abstract

Ultra-high energy cosmic rays (UHECRs) may originate from the decay of massive relic particles in the dark halo of the Galaxy, or they may be produced by supermassive black holes in the nuclei of nearby galaxies. The anisotropy in the arrival directions is studied in four dark halo models (cusped, isothermal, triaxial and tilted) and in four galaxy samples (galaxies intrinsically brighter than Centaurus A within 50 and 100 Mpc, and brighter than M32 within 50 and 100 Mpc). In decaying dark matter models, the amplitude of the anisotropy is controlled by the size of the Galactic halo, while the phase is controlled by the shape. In the northern hemisphere, the amplitude is about 0.5 for cusped haloes, but falls to roughly 0.3 for isothermal haloes. The phase points in the direction of the Galactic Centre, with deviations of up to 30 degrees possible for triaxial and tilted haloes. The effect of the halo of M31 is too weak to provide conclusive evidence for the decaying dark matter origin of UHECRs. In extragalactic models, samples of galaxies brighter than Centaurus A produce substantial anisotropies (roughly 1.8), much larger than the limits set by the available data. If all galaxies brighter than M32 contribute, then the anisotropy is more modest (roughly 0.5) and is directed toward mass concentrations in the supergalactic plane, like the Virgo cluster. Predictions are made for the southern hemisphere station of the Pierre Auger Observatory. If the UHECRs have a Galactic origin, then the phase points towards the Galactic Centre. If they have an extragalactic origin, then it points in the rough direction of the Fornax cluster. This provides an unambiguous discriminant and requires about 350-500 events at South Auger., Comment: 38 pages, 8 figures. This version is identical to the one in press at Astroparticle Physics

Published
2016

31. Response of the Thermal Conductivity as a Function of Water Content of a Burnt Mediterranean Loam Soil

Author

Francesc Ferrer, Carles M. Rubio, Xavier Úbeda, and Universitat de Barcelona

Subjects
Hydrology, Mediterranean climate, Moisture, Soil test, Incendis forestals, Forest fires, Soil science, Thermal conductivity, Volume (thermodynamics), Sòls, Loam, Heat transfer, Soils, Environmental science, Water content
Abstract

The purpose of this research is to explore the variability on the soil thermal conductivity -λ- after a prescribe fire, and to assess the effects of the ashes on the heat transfer once it"s were incorporated into the soil matrix. Sampling plot was located in the Montgrí Massif (NE of Spain). A set of 42 soil samples between surface and 5 cm depth was collected before and after the fire. To characterize the soil chemical and physical variables were analyzed. To determine the vari-ability on the soil λ a dry-out curve per scenario (before and after fire) was determined. SoilRho® method based on ASTM D-5334-08 which was validated by LabFerrer was used. Soil thermal conductivity has shown changes in their values. Indeed, in all moisture scenarios the values of soil λ decreased after soil was burnt. The critical point in the rela-tionship ϴ (λ) for the soil after fire which always was stronger than soil before to be burnt. Soil with"white" ashes showed a high thermal conductivity. An X-Ray diffractometry analysis allowed to clarify and to verify these results. To sum up, we could say that thermal conductivity presents changes when the scenario changes, i.e. before and after to be burnt. On the other hand, the volume of ashes incorporated on the soil increased the differences between no burnt and burnt soil, showing even some improvements on the heat transfer when water content started to govern the process.

Published
2012
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32. Influence of the Hysteretic Behaviour on Silt Loam Soil Thermal Properties

Author

Ramon Josa, Francesc Ferrer, and Carles M. Rubio

Subjects
Soil thermal properties, Materials science, Thermal conductivity, Degree of saturation, Loam, Soil water, Soil science, Thermal diffusivity, Heat capacity, Water content
Abstract

The aim of this research is to explore the influence of hysteresis on heat transport in soils under experimental laboratory conditions. The obtained results shown that, thermal properties as are volumetric specific heat capacity (Cv) and thermal conductivity (θ) showed a positive linear correlation with soil volumetric water content (θ). However, thermal diffusivity values (θ) shown divergences between heat transferred and soil moisture. A spatial-temporal hysteresis pattern was observed on the whole of the thermal properties. This fact was related with factors as: degree of saturation, the influence of temperature difference on the heat transport, and the geometry of the water layer around the particle.

Published
2011
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34. Cosmological acceleration from a gas of strings

Author

Francesc Ferrer

Subjects
High Energy Physics - Theory, Physics, Nuclear and High Energy Physics, FOS: Physical sciences, Acceleration (differential geometry), String (physics), Atomic and Molecular Physics, and Optics, Cosmology, Microscopic scale, Term (time), Metric expansion of space, Extra dimensions, Theoretical physics, High Energy Physics - Theory (hep-th)
Abstract

In string gas cosmology, the extra dimensions of the underlying theory are kept at a microscopic scale by a gas of strings. In the matter-dominated era, however, dust pressure can lead to oscillations of the extra dimensions and to acceleration in the three visible dimensions, even with a vanishing cosmological term. We review the resulting oscillating expansion history, that provides an acceptable fit to the observed accelerated expansion of the Universe., 6 pages, 2 figures. Proceedings of the GGI Dark Matter and Dark Energy conference

Published
2009
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35. Anisotropy studies around the galactic centre at EeV energies with the Auger Observatory

Author

K. Daumiller, J. Sorokin, D. Gonzalez, Miroslav Pech, Marcio Aparecido Muller, Catherine Newman-Holmes, F. Suarez, D. Garcia-Pinto, A. Zepeda, A. Letessier-Selvon, H. O. Klages, Hernán Asorey, W. Slater, M. Zavrtanik, A. Zech, G. Miele, M. Ave, R. M. de Almeida, S. Maltezos, R. Meyhandan, M. D. Healy, K. Arisaka, L. Prado, I. Lhenry-Yvon, Francesc Ferrer, Andreas Kopmann, R. Mussa, X. Garrido, Jc Bacelar, E. Moreno, L. Perrone, A. Gorgi, O. Deligny, M. Gonçalves do Amaral, E. M. Santos, Helio Nogima, F. Arneodo, Mohsen Harakeh, D. R. Claes, D. Maurizio, N. Kunka, H. Glass, Jan Kuijpers, C. Di Giulio, I. C. Maris, Enrique Zas, E. Kemp, T. Beau, José Eduardo Martinez, Xavier Bertou, D. Torresi, B. R. Becker, Petr Schovanek, Bruce R. Dawson, Tim Huege, C. J. Todero Peixoto, C. H. Wiebusch, Jaime Alvarez-Muñiz, S. Westerhoff, Jörg R. Hörandel, T. Bergmann, B. Wilczynska, M. T. Dova, L. Nožka, T. Vo Van, F. Schüssler, C. Timmermans, L. A. de Carvalho, J. N. Capdevielle, J. Chye, A. Della Selva, C. Grunfeld, V. Tunnicliffe, J. Gitto, R. R. McNeil, A. Chou, L. Nellen, R. Piegaia, L. Villasenor, T. McCauley, Carola Dobrigkeit, A. Cordier, C. Bonifazi, H. Blümer, A. Lopez Agüera, S. Ostapchenko, T. Dang Quang, I. Valiño, A. Insolia, M. E. Mancenido, Milena Horvat, M. Kleifges, Esteban Roulet, C. Grupen, Andrej Filipcic, J. Knapp, Warner A. Miller, C. Aramo, Henrique M. J. Barbosa, Alan Watson, E. Armengaud, R. Gómez Herrero, R. A. Vázquez, R. Engel, Gualberto Avila, Ingomar Allekotte, M. Patel, H. Spinka, Heiko Geenen, G. Rodriguez, Dariusz Gora, E. J. Quel, A. Tripathi, S. Kuhlman, M. Barkhausen, S. B. Clay, R. Fonte, B. E. Smith, G. Mancarella, A. D. Supanitsky, Corinne Berat, M. Giller, C. Morello, R. Ticona, W. Tkaczyk, M. C. Medina, J. Rodríguez Martino, T. Yamamoto, T. Venters, J. Pallotta, J. Matthews, A. Ewers, V. Van Elewyck, O. Blanch-Bigas, Angela V. Olinto, A. Etchegoyen, E. Strazzeri, J. Kleinfeller, B. Garcia, C. Bleve, Oleg Kalashev, Luis A. Anchordoqui, C. Hojvat, J. C. Hamilton, P. D. J. Clark, A. C. Fauth, Carlos Escobar, M. A. L. de Oliveira, Marco Aglietta, P. Bernardini, D. Lebrun, V. Verzi, I. De Mitri, F. Montanet, Jose Chinellato, A. Haungs, S. Maldera, B. Revenu, C. Robledo, P. Gouffon, O. Pisanti, K.-H. Becker, O. Tascau, A. Grillo, D. D'Urso, M. Zha, Vincenzo Rizi, P. Younk, Y. Petrov, Giuseppe Longo, C. Alvarez, R. Cester, Jose A. Bellido, L. F. A. Oliveira, L. del Peral, D. V. Camin, F. Sanchez, D. Allard, A. Horneffer, Dusan Mandat, J. Aublin, L. Cazon, J. A. J. Matthews, C. Aguirre, P. Allison, Silvia Mollerach, R. Bonino, J. W. Cronin, J.R. Rodriguez Rojo, J. Rosado, Antonio Velarde, T. Pierog, J. C. D'Olivo, A. Menshikov, E. Fokitis, D. Rodríguez Frías, E. Parizot, J. M. Brunet, M. Ortiz, D. Warner, G. Sigl, Petr Travnicek, R. W. Clay, A. Fernandez, B. Fick, T. Paul, Alejandro Luis Veiga, T. Asch, J. Brack, T. Schmidt, H. Dembinski, M. A. DuVernois, A. Kusenko, N. Martinez, G. Medina, T. Nguyen Thi, A. Geranios, T. Bäcker, M. Kaducak, Fabian Gobbi, D. Semikoz, G. Wieczorek, J. F. Valdés Galicia, Karl-Heinz Kampert, Antonella Castellina, B. Keilhauer, N. Fazzini, A. Tonachini, H. C. Reis, M. Ambrosio, R. C. Shellard, H. J. Mathes, S. Reucroft, D. Harari, Matthias Leuthold, A. G. Mariazzi, C. Morris, G. Cataldi, S. Parlati, Francisco J. Blanco, H. Wahlberg, Bei Cai, G. Sequeiros, C. Roucelle, Darko Veberic, S. Coutu, A. M. van den Berg, Daniel Omar Badagnani, Luis N. Epele, Heino Falcke, M. Urban, J. Pouryamout, Lawrence Wiencke, G. Parente, D. Heck, P. Skelton, M. Gonzalez, R. Knapik, F. Arqueros, H. Schieler, J. Lee, M. Prouza, A. Smialkowski, Y. Kolotaev, N. Smetniansky De Grande, Bruno L. Lago, G. Navarra, N. G. Busca, V. M. Olmos-Gilbaja, C. Meurer, M. Tueros, W. J. M. de Mello, P. Darriulat, P. Bauleo, D. Fazio, J. G. Gonzalez, S. Harmsma, C. Rivière, A. Tamburro, M. Monasor, V. Scherini, Diego Melo, Segev BenZvi, Mario Scuderi, A. Dorofeev, J. Xu, M. Roth, R. Nichol, Gregory R Snow, P. Sommers, E. Menichetti, G. Matthiae, Corbin Covault, F. Gomez Albarracin, T. Suomijärvi, P. Blasi, P. Privitera, J. Gutiérrez, S. Robbins, A. Filevich, D. Pham Ngoc, R. Pelayo, J. Rautenberg, M. Iarlori, P. L. Ghia, Subir Sarkar, M. Boratav, P. Mantsch, M. Boháčová, U. Cotti, S. Hartmann, J. C. Diaz, R. Ulrich, J. Beatty, D. Martello, Juan Pablo Gongora, Martin Erdmann, J. Swain, M. Risse, German Ros, N. Nierstenhöfer, W. Fulgione, M. Hrabovský, D. Tscherniakhovski, R. Lopez, J. Pȩkala, J. R. T. de Mello Neto, A. Stutz, P. L. Biermann, Rossella Caruso, O. Martinez, S. J. Sciutto, M. I. Micheletti, G. Gelmini, P. Buchholz, P. O. Mazur, J. L. Harton, Piotr Homola, Marcos Santander, P. Facal San Luis, D. Zavrtanik, C. Wileman, D. Fuhrmann, J. Oehlschläger, O. Krömer, Z. Szadkowski, M. Ziolkowski, Beatriz B. Siffert, S. Petrera, J. Řídký, F. Guarino, D. Newton, T. Waldenmaier, G. P. Guedes, M. Malek, Radomir Smida, C. Delle Fratte, F. Salamida, B. Morales, T. N. Pham Thi, M. G. Winnick, G. Tristram, J. D. Hague, P. LeBrun, H. Wilczynski, P. Walker, P. Boghrat, L. Valore, D. Barnhill, M. Roberts, V. Grassi, A. Chiavassa, G. Salina, D. Nosek, G. Maurin, M. Gómez Berisso, O. Wainberg, T. A. Porter, A. Risi, C. Lachaud, R. Sato, B. Connolly, D. Monnier Ragaigne, J. Abraham, P. Billoir, A. Lucero, A. Meli, L. Garrard, S. L. C. Barroso, M. Videla, Thomas Hebbeker, B. S. Atulugama, M. Unger, J. C. Anjos, K. S. Caballero-Mora, Olaf Scholten, Humberto Ibarguen Salazar, S. Dagoret-Campagne, D. Nitz, D. Dornic, J. Chauvin, S. De Jong, C. De Donato, Miguel Mostafa, T. Ohnuki, P. Petrinca, M. McEwen, V. de Souza, S. Vorobiov, H. Gemmeke, A. F. Barbosa, M. Palatka, I. M. Pepe, A. C. Rovero, M. Gold, A. Tamashiro, K. Payet, L. Otero, I. Fleck, B. Rouillé-d'Orfeuil, P. Sokolsky, D. H. Koang, L. Voyvodic, G. A. Medina Tanco, S. Ferry, J., Abraham, M., Aglietta, C., Aguirre, D., Allard, I., Allekotte, P., Allison, C., Alvarez, J., Alvarez Muniz, M., Ambrosio, L., Anchordoqui, J. C., Anjo, C., Aramo, K., Arisaka, E., Armengaud, F., Arneodo, F., Arquero, T., Asch, H., Asorey, B. S., Atulugama, J., Aublin, M., Ave, G., Avila, J., Bacelar, T., Backer, D., Badagnani, A. F., Barbosa, H. M. J., Barbosa, M., Barkhausen, D., Barnhill, S. L. C., Barroso, P., Bauleo, J., Beatty, T., Beau, B. R., Becker, K. H., Becker, J. A., Bellido, S., Benzvi, C., Berat, T., Bergmann, Bernardini, Paolo, X., Bertou, P. L., Biermann, P., Billoir, O., Blanch Biga, F., Blanco, P., Blasi, Bleve, Carla, H., Blumer, P., Boghrat, M., Bohacova, C., Bonifazi, R., Bonino, M., Boratav, J., Brack, J. M., Brunet, P., Buchholz, N. G., Busca, K. S., Caballero Mora, B., Cai, D. V., Camin, J. N., Capdevielle, R., Caruso, A., Castellina, G., Cataldi, L., Cazon, R., Cester, J., Chauvin, A., Chiavassa, J. A., Chinellato, A., Chou, J., Chye, D., Clae, P. D. J., Clark, R. W., Clay, S. B., Clay, B., Connolly, A., Cordier, U., Cotti, S., Coutu, C. E., Covault, J., Cronin, S., Dagoret Campagne, T., Dang Quang, P., Darriulat, K., Daumiller, B. R., Dawson, R. M., de Almeida, L. A., de Carvalho, C., De Donato, S. J., de Jong, W. J. M. de Mello J., R., J. R. T., de Mello Neto, DE MITRI, Ivan, M. A. L., de Oliveira, V., de Souza, L., del Peral, O., Deligny, A., Della Selva, C., Delle Fratte, H., Dembinski, C., Di Giulio, J. C., Diaz, C., Dobrigkeit, J. C., D’Olivo, D., Dornic, A., Dorofeev, M. T., Dova, D., D’Urso, M. A., Duvernoi, R., Engel, L., Epele, M., Erdmann, C. O., Escobar, A., Etchegoyen, A., Ewer, P., Facal San Lui, H., Falcke, A. C., Fauth, D., Fazio, N., Fazzini, A., Fernandez, F., Ferrer, S., Ferry, B., Fick, A., Filevich, A., Filipcic, I., Fleck, E., Fokiti, R., Fonte, D., Fuhrmann, W., Fulgione, B., Garcia, D., Garcia Pinto, L., Garrard, X., Garrido, H., Geenen, G., Gelmini, H., Gemmeke, A., Geranio, P. L., Ghia, M., Giller, J., Gitto, H., Gla, F., Gobbi, M. S., Gold, F., Gomez Albarracin, M., Gomez Berisso, R., Gomez Herrero, M., Goncalves do Amaral, J. P., Gongora, D., Gonzalez, J. G., Gonzalez, M., Gonzalez, D., Gora, A., Gorgi, P., Gouffon, V., Grassi, A., Grillo, C., Grunfeld, C., Grupen, F., Guarino, G. P., Guede, J., Gutierrez, J. D., Hague, J. C., Hamilton, M. N., Harakeh, D., Harari, S., Harmsma, S., Hartmann, J. L., Harton, M. D., Healy, T., Hebbeker, D., Heck, C., Hojvat, P., Homola, J., Horandel, A., Horneffer, M., Horvat, M., Hrabovsky, M., Iarlori, A., Insolia, M., Kaducak, O., Kalashev, K. H., Kampert, B., Keilhauer, E., Kemp, H. O., Klage, M., Kleifge, J., Kleinfeller, R., Knapik, J., Knapp, D. H., Koang, Y., Kolotaev, A., Kopmann, O., Kromer, S., Kuhlman, J., Kuijper, N., Kunka, A., Kusenko, C., Lachaud, B. L., Lago, D., Lebrun, P., Lebrun, J., Lee, A., Letessier Selvon, M., Leuthold, I., Lhenry Yvon, G., Longo, R., Lopez, A., Lopez Aguera, A., Lucero, S., Maldera, M., Malek, S., Maltezo, Mancarella, Giovanni, M. E., Mancenido, D., Mandat, P., Mantsch, A. G., Mariazzi, I. C., Mari, Martello, Daniele, N., Martinez, J., Martinez, O., Martinez, H. J., Mathe, J., Matthew, J. A. J., Matthew, G., Matthiae, G., Maurin, D., Maurizio, P. O., Mazur, T., Mccauley, M., Mcewen, R. R., Mcneil, G., Medina, M. C., Medina, G., Medina Tanco, A., Meli, D., Melo, E., Menichetti, A., Menshikov, Meurer, C. h. r., R., Meyhandan, M. I., Micheletti, G., Miele, W., Miller, S., Mollerach, M., Monasor, D., Monnier Ragaigne, F., Montanet, B., Morale, C., Morello, E., Moreno, C., Morri, M., Mostafa', M. A., Muller, R., Mussa, G., Navarra, L., Nellen, C., Newman Holme, D., Newton, T., Nguyen Thi, R., Nichol, N., Nierstenhofer, D., Nitz, H., Nogima, D., Nosek, L., Nozka, J., Oehlschlager, T., Ohnuki, A., Olinto, L. F. A., Oliveira, V. M., Olmos Gilbaja, M., Ortiz, S., Ostapchenko, L., Otero, M., Palatka, J., Pallotta, G., Parente, E., Parizot, S., Parlati, M., Patel, T., Paul, K., Payet, M., Pech, J., Pekala, R., Pelayo, I. M., Pepe, Perrone, Lorenzo, S., Petrera, P., Petrinca, Y., Petrov, D., Pham Ngoc, T. N., Pham Thi, R., Piegaia, T., Pierog, O., Pisanti, T. A., Porter, J., Pouryamout, L. Prado J., R., P., Privitera, M., Prouza, E. J., Quel, J., Rautenberg, H. C., Rei, S., Reucroft, B., Revenu, J., Ridky, A., Risi, M., Risse, C., Riviere, V., Rizi, S., Robbin, M., Robert, C., Robledo, G., Rodriguez, D., Rodriguez Fria, J., Rodriguez Martino, J., Rodriguez Rojo, G., Ro, J., Rosado, M., Roth, C., Roucelle, B., Rouille' d’Orfeuil, E., Roulet, A. C., Rovero, F., Salamida, H., Salazar, G., Salina, F., Sanchez, M., Santander, E. M., Santo, S., Sarkar, R., Sato, V., Scherini, T., Schmidt, O., Scholten, P., Schovanek, F., Schussler, S. J., Sciutto, M., Scuderi, D., Semikoz, G., Sequeiro, R. C., Shellard, B. B., Siffert, G., Sigl, P., Skelton, W., Slater, N., Smetniansky De Grande, A., Smialkowski, R., Smida, B. E., Smith, G. R., Snow, P., Sokolsky, P., Sommer, J., Sorokin, H., Spinka, E., Strazzeri, A., Stutz, F., Suarez, T., Suomijarvi, A. D., Supanitsky, J., Swain, Z., Szadkowski, A., Tamashiro, A., Tamburro, O., Tascau, R., Ticona, C., Timmerman, W., Tkaczyk, C. J., Todero Peixoto, A., Tonachini, D., Torresi, P., Travnicek, A., Tripathi, G., Tristram, D., Tscherniakhovski, M., Tuero, V., Tunnicliffe, R., Ulrich, M., Unger, M., Urban, J. F., Valdes Galicia, I., Valino, L., Valore, A. M., van den Berg, V., van Elewyck, R. A., Vazquez, D., Veberic, A., Veiga, A., Velarde, T., Venter, V., Verzi, M., Videla, L., Villasenor, T., Vo Van, S., Vorobiov, L., Voyvodic, H., Wahlberg, O., Wainberg, T., Waldenmaier, P., Walker, D., Warner, A. A., Watson, S., Westerhoff, C., Wiebusch, G., Wieczorek, L., Wiencke, B., Wilczynska, H., Wilczynski, C., Wileman, M. G., Winnick, J., Xu, T., Yamamoto, P., Younk, E., Za, D., Zavrtanik, M., Zavrtanik, A., Zech, A., Zepeda, M., Zha, M., Ziolkowski, APC - Astrophysique des Hautes Energies (APC - AHE), AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Accélérateur Linéaire (LAL), APC - Cosmologie, Physique Corpusculaire et Cosmologie - Collège de France (PCC), Collège de France (CdF)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Collège de France (CdF)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-AstroParticule et Cosmologie (APC (UMR_7164)), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, APC - THEORIE, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut für theoretische Physik, Universität Hamburg (UHH)-Universität Hamburg (UHH), PIERRE AUGER, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut für theoretische Physik, Guarino, Fausto, Longo, Giuseppe, Aramo, Carla, DELLA SELVA, Angelo, Miele, Gennaro, Pisanti, Ofelia, Valore, Laura, D'Urso, Domenico, Auger, Collaboration, Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut für theoretische Physik

Subjects
[SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Astronomy, Astrophysics::High Energy Astrophysical Phenomena, media_common.quotation_subject, FOS: Physical sciences, Osservatorio Pierre Auger, Flux, Cosmic ray, Astrophysics, 01 natural sciences, Auger, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Raggi cosmici, Observatory, 0103 physical sciences, Anisotropies, Centro galattico, Galactic centre, Cosmic rays, 010303 astronomy & astrophysics, Ciencias Exactas, media_common, Pierre Auger Observatory, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Anisotropie, centro galáctico, Astrophysics (astro-ph), Astrophysics::Instrumentation and Methods for Astrophysics, Gamma ray, Física, Astronomy and Astrophysics, Radiación cósmica, Anisotropía, Galaxy, Sky, Experimental High Energy Physics
Abstract

Data from the Pierre Auger Observatory are analyzed to search for anisotropies near the direction of the Galactic Centre at EeV energies. The exposure of the surface array in this part of the sky is already significantly larger than that of the fore-runner experiments. Our results do not support previous findings of localized excesses in the AGASA and SUGAR data. We set an upper bound on a point-like flux of cosmic rays arriving from the Galactic Centre which excludes several scenarios predicting sources of EeV neutrons from Sagittarius $A$. Also the events detected simultaneously by the surface and fluorescence detectors (the `hybrid' data set), which have better pointing accuracy but are less numerous than those of the surface array alone, do not show any significant localized excess from this direction., Comment: Matches published version

Published
2007
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36. A novel approach to derive halo-independent limits on dark matter properties

Author

Alejandro Ibarra, Francesc Ferrer, and Sebastian Wild

Subjects
Physics, Elastic scattering, Particle physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Dark matter, Null (mathematics), FOS: Physical sciences, Astronomy and Astrophysics, Computer Science::Computation and Language (Computational Linguistics and Natural Language and Speech Processing), Astrophysics::Cosmology and Extragalactic Astrophysics, Dark matter halo, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), Neutrino detector, Halo, Neutrino, Nucleon, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We propose a method that allows to place an upper limit on the dark matter elastic scattering cross section with nucleons which is independent of the velocity distribution. Our approach combines null results from direct detection experiments with indirect searches at neutrino telescopes, and goes beyond previous attempts to remove astrophysical uncertainties in that it directly constrains the particle physics properties of the dark matter. The resulting halo-independent upper limits on the scattering cross section of dark matter are remarkably strong and reach $\sigma_{\text{SI}}^{p} \lesssim 10^{-43} \, (10^{-42})~\text{cm}^2$ and $\sigma_{\text{SD}}^{p} \lesssim 10^{-37} \, (3\times 10^{-37 })~\text{cm}^2$, for dark matter particles of $m_{\text{DM}}\sim 1~\text{TeV}$ annihilating into $W^+W^-$ ($b\bar b$), assuming $\rho_\text{loc}=0.3\text{ GeV}/\text{cm}^3$., Comment: 18 pages, 4 figures. Matches published version

Published
2015

37. Erratum: VERITAS deep observations of the dwarf spheroidal galaxy Segue 1 [Phys. Rev. D85, 062001 (2012)]

Author

M. P. Connolly, D. Staszak, K. Ragan, R. Dickherber, S. Thibadeau, L. Ciupik, A. Varlotta, H. J. Rose, D. S. Hanna, T. C. Arlen, P. Kaaret, D. B. Saxon, E. Collins-Hughes, G. H. Sembroski, G. Hughes, Matthias Beilicke, A. McCann, A. Cesarini, M. Vivier, John L. Quinn, Francesc Ferrer, S. Archambault, Reshmi Mukherjee, K. Tsurusaki, Gernot Maier, Nahee Park, S. P. Wakely, C. Skole, A. Bouvier, Geza Gyuk, J. E. Ward, R. A. Ong, Thomas Weisgarber, Daniel Gall, E. Aliu, Matthew R. Orr, David Kieda, K. L. Byrum, Jodi Christiansen, J. S. Perkins, S. M. Bradbury, G. Tešić, David A. Williams, Lucy Fortson, A. Cannon, Pratik Majumdar, V. V. Vassiliev, T. Aune, I. Telezhinsky, Jamie Holder, S. Godambe, J. P. Dumm, J. Ruppel, Q. Feng, L. C. Reyes, Henric Krawczynski, Amy Furniss, A. J.R. Weinstein, T. B. Humensky, M. Schroedter, Wei Cui, S. McArthur, V. Bugaev, Wystan Benbow, F. Krennrich, G. Finnegan, A. W. Smith, M. Theiling, A. S Madhavan, A. D. Falcone, E. Roache, G. D. Şentürk, H. Huan, J. H. Buckley, P. Moriarty, Nicola Galante, J. Grube, R. G. Wagner, N. Karlsson, Sinéad M. Griffin, Y. Khassen, G. Decerprit, S. Vincent, M. Kertzman, A. N. Otte, P. T. Reynolds, B. Zitzer, Manel Errando, J. P. Finley, T. C. Weekes, M. Pohl, K. Lee, and H. Prokoph

Subjects
Physics, Gravitation, Nuclear and High Energy Physics, Dark matter, Gamma ray, Astronomy, Astrophysics, Segue, Cosmology, Dwarf galaxy, Dwarf spheroidal galaxy
Published
2015
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38. El panoràmic 2016

Author

Torre Jussana-Centre de Serveis a les Associacions, Consell d'Associacions de Barcelona, Observatori del Tercer Sector, Fundació Pere Tarrés, Fundació Francesc Ferrer i Guàrdia, Fundació la Caixa, Fernández, Montse, Vidal, Pau, Torre Jussana-Centre de Serveis a les Associacions, Consell d'Associacions de Barcelona, Observatori del Tercer Sector, Fundació Pere Tarrés, Fundació Francesc Ferrer i Guàrdia, Fundació la Caixa, Fernández, Montse, and Vidal, Pau

Abstract

En aquesta edició s'ofereix un anàlisi de la realitat de les entitats no lucratives catalanes durant el 2016

Published
2017

39. Coordinación entre servicios de urgencias. Un modelo eficaz en la planificación sanitaria

Author

Jaume Monmany, Josep M. Guardiola, Lluís Pascual, Joan Antoni Oliva, Francesc Ferrer, Guillermo J. Vázquez, Eva Coma, Pilar Madrid, and Rosa Teixell

Subjects
Health Policy, General Medicine
Abstract

Resumen Objetivo Evaluar, mediante un estudio de intervencion con controles historicos, la optimizacion del traslado de pacientes desde el servicio de urgencias de un hospital de alta complejidad –centro emisor (CE)– a un hospital de menor complejidad –centro receptor (CR)– durante el invierno. Material y metodos La intervencion consistio en la creacion de los siguientes recursos y dispositivos: criterios de seleccion de pacientes aptos para ser trasladados, sistema exclusivo de comunicacion, un horario de traslados, obtencion de resultados pendientes de pruebas efectuadas en el CE, una unidad de hospitalizacion especifica en el CR, circuito de altas y prealtas en el CR, normas escritas de coordinacion entre la unidad asistencial, la Unidad de Trabajo Social y el Servicio de Farmacia Hospitalaria, hoja de acogida y un circuito de informacion a las residencias sanitarias. Resultados Se traslado a 247 pacientes. Ningun paciente permanecio en el area de urgencias del CR. No hubo ninguna desprogramacion de ingresos en el CR. El indice de reingreso a los 30 dias fue del 2,4%. La estancia media en el CR fue de 5,63 dias. El indice funcional fue de 0,6; la razon de funcionamiento estandar, 0,6; la diferencia atribuible al funcionamiento, -4,0 y el impacto, -706. Conclusiones La intervencion en el traslado de pacientes desde un servicio de urgencias de un centro de alta complejidad a un centro de menor complejidad, para evitar el colapso del primero, mejora la calidad asistencial de los pacientes trasladados y evita mermar la del hospital receptor.

Published
2004
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40. On‐Farm Monitoring of Soil Nitrate‐Nitrogen in Irrigated Cornfields in the Ebro Valley (Northeast Spain)

Author

Francesc Ferrer, Miquel Aran, Claudio O. Stöckle, Josep M. Villar-Mir, and Pere Villar-Mir

Subjects
Human fertilization, Agronomy, chemistry, Soil nitrate, Environmental science, Growing season, Grain yield, chemistry.chemical_element, Leaching (agriculture), Agronomy and Crop Science, Nitrogen, Zea mays, N fertilizer
Abstract

The irrigated area served by the Canal d'Urgell, a semiarid region in the Ebro Valley (northeast Spain), presents problems of ground water pollution by nitrates. Corn (Zea mays L.) is widely grown in this area, and N fertilization in corn production is the major source of N input in the area, with application rates in excess of crop requirements. In this study, we monitored several commercial cornfields for soil NO 3 -N levels, crop N uptake, and crop productivity over a 2-yr period to quantify the relationship among soil NO 3 -N, N fertilizer rates, crop N use, and N loss through leaching. Monitoring soil NO 3 -N profiles showed that in some fields, soil NO 3 -N was transported to deeper layers in the soil during the growing season. In many cases, important accumulation of NO 3 -N was observed at the bottom of the soil at physiological maturity, increasing the risk of winter leaching. Soil N availability, calculated as preplanting soil nitrate test + N fertilizer, was neither related to plant N uptake nor final biomass and grain yield. In some plots, the occurrence of drought during the growing season was more decisive than soil-available N in explaining crop N uptake and grain yield differences. Available N levels found in the soil were above 370 kg ha -1 in all cases. Apparently, these levels were enough to satisfy the crop N requirements to achieve yields above 11 to 12 Mg ha -1 . Overall data showed that there is an excess of N in the system.

Published
2002
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41. Intergalactic magnetic field spectra from diffuse gamma rays

Author

Tanmay Vachaspati, Wenlei Chen, Borun D. Chowdhury, Hiroyuki Tashiro, and Francesc Ferrer

Subjects
Physics, High Energy Astrophysical Phenomena (astro-ph.HE), High Energy Physics - Theory, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Astrophysics::High Energy Astrophysical Phenomena, Monte Carlo method, Gamma ray, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Spectral line, Magnetic field, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), High Energy Physics - Theory (hep-th), Space and Planetary Science, Magnetic helicity, Intergalactic travel, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Non-vanishing parity-odd correlators of gamma ray arrival directions observed by Fermi-LAT indicate the existence of a helical intergalactic magnetic field (Tashiro et al.2013). We successfully test this hypothesis using more stringent cuts of the data, Monte Carlo simulations with Fermi-LAT time exposure information, separate analyses for the northern and southern galactic hemispheres, and confirm predictions made in Tashiro & Vachaspati (2014). With some further technical assumptions, we show how to reconstruct the magnetic helicity spectrum from the parity-odd correlators., 12 pages, 8 figures

Published
2014

42. Search for GeV γ-Ray Pair Halos Around Low Redshift Blazars

Author

Francesc Ferrer, J. H. Buckley, and Wenlei Chen

Subjects
Physics, Astrophysics::High Energy Astrophysical Phenomena, Gamma ray, General Physics and Astronomy, Astronomy, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Redshift, law.invention, Telescope, law, Observational cosmology, Intergalactic travel, Halo, Blazar, Fermi Gamma-ray Space Telescope
Abstract

We report on the results of a search for γ-ray pair halos with a stacking analysis of low redshift blazars using data from the Fermi Large Area Telescope. For this analysis we used a number of a priori selection criteria, including the spatial and spectral properties of the Fermi sources. The angular distribution of ~1 GeV photons around 24 stacked isolated high-synchrotron-peaked BL Lacs with redshift z0.5 shows an excess over that of pointlike sources. A frequentist test yields a p value of p~0.01 for the extended emission against the point-source hypothesis. A Bayesian estimation provides Bayes factors log_{10}B_{10}2, consistent with expectations for pair halos produced in the intergalactic magnetic fields with strength B_{IGMF}~10^{-17}-10^{-15} G.

Published
2014

44. Erratum to 'Atmospheric effects on extensive air showers observed with the surface detector of the Pierre Auger observatory'[Astroparticle Physics 32(2) (2009), 89-99]

Author

P. Lebrun, R. López, Karen S. Caballero-Mora, L. Valore, M. Gold, Martin Erdmann, I. Zaw, V. C. Holmes, D. Lebrun, C. Macolino, J. Oehlschläger, I. Dutan, Roger W Clay, W. J. M. de Mello, Markus Risse, U. Cotti, D. Heck, Carola Dobrigkeit, R. F. Gamarra, I. Valiño, P. Wahrlich, T. Suomijärvi, J. Pallotta, E. J. Quel, I. Torres, Alan Watson, L. Cazon, S. Navas, M. Melissas, M. Hrabovsky, C. Hojvat, R. A. Vázquez, O. Taşcaǧu, F. Sánchez, K. Louedec, Paulo J. S. Gonçalves, V. Rizzi, Mariangela Settimo, K. H. Kampert, J. PeĶala, E. Trovato, Wagner Carvalho, Iván Sidelnik, M.E. Ortiz, A. Filipčič, A. Rouillé-d'Orfeuil, H.O. Klages, A. Redondo, D.V. Semikoz, H. Blümer, Charles Timmermans, C. Riviere, F. Sarazin, Kai Daumiller, M. S. A. B. Leão, M. Urban, S. Petrera, G. Parente, E. M. Santos, Piotr Homola, P. Facal San Luis, M. Grigat, Ralf Ulrich, R. M. de Almeida, J. Pochon, Richard Dallier, A. C. Rovero, Luis A. Anchordoqui, Bruce R. Dawson, M. D. Healy, P. T. Nhung, H. R. Marquez Falcon, Jaime Alvarez-Muñiz, D. Schuster, K. Payet, P.O. Mazur, Darko Veberič, C. Bleve, F. Arneodo, S. Gambetta, J. Kleinfeller, Petr Travnicek, R. Ticona, Martina Bohacova, Patrick Allison, J. G. Gonzalez, C. Morris, V. Pirrpnello, A. Schmidt, R. Bonino, D. Allard, Rodrigo Pelayo, S. Westerhoff, L. Nellen, Miguel Mostafá, C. Morello, K. D. de Vries, Vasiliki Pavlidou, H. M. Spinka, R. Piegaia, O. Krömer, J. Sorokin, van den Ad M Berg, A. C. Fauth, R. M. Kieckhafer, Juan Moreno, Daniel Kuempel, Carlos Escobar, A. Creusot, S. Maldera, B. Revenu, J. R. Vázquez, A. Italiano, D. Melo, T. Huege, Jeffrey Brack, J. Rautenberg, O. Wainberg, Maria-Teresa Dova, T. Schmidt, S. Grebe, Olaf Scholten, W. Fulgione, H. Lyberis, Jose A. Bellido, Stefano Argiro, Humberto Ibarguen Salazar, B. Keilhauer, Catherine Newman-Holmes, D. B. Tridapalli, P. Bernardini, J. Allen, D. Harari, M. Zavrtanik, H. Schieler, Matthias Leuthold, Fabrizio Ortolani, W. C. Brown, Peter L. Biermann, E. Petermann, D. D'Urso, N. T. Thao, Gennaro Miele, Jaime Rosado, K.-H. Becker, D. Warner, Corinne Berat, M. Giller, S. J. Sciutto, D. García Gámez, R. Pesce, Miroslav Pech, J. Schovancova, Antonella Castellina, Paul Sommers, Lisa M. Goggin, R. Bruijn, Graciela B. Gelmini, J. Lozano Bahilo, Segev BenZvi, N. Nierstenhoefer, M. Monasor, A. Horneffer, M. Pimenta, A. G. Mariazzi, C. Robledo, A. Haungs, John G. Lee, J. L. Harton, E. Parizot, R. Squartini, C. E. Santo, Corbin Covault, T. Paul, Y. Petrov, D. Martello, C. De Donato, R. Luna García, P. Gouffon, P. N. Dong, R. Cester, W. Tkaczyk, J. D. Hague, Jörg R. Hörandel, B. Morales, Paolo Privitera, K. Arisaka, S. Fliescher, Lino Miramonti, M. S. Sutherland, P. Petrinca, M. Ziolkowski, D. Nitz, P. Mantsch, F. A. S. Rezende, C. Lachaud, U. Giaccari, C. Bonifazi, O. Martínez Bravo, H. Wu, M. D. Rodríguez-Frías, J. Gutiérrez, M. De Domenico, José Eduardo Martinez, J. A.J. Matthews, Xavier Bertou, G. Navarra, Olivier Ravel, E. Menichetti, R. Knapik, F. Schüssler, D. Pakk Selmi-Dei, I. Lhenry-Yvon, Hernan Wahlberg, Francesc Ferrer, A. Chiavassa, Sofia Andringa, K. B. Barber, A. Smialkowski, C. A. Moura, S. L.C. Barroso, T. Yamamoto, Antonio Velarde, A. Zepeda, Rossella Caruso, Pietro Oliva, A. Lucero, Pedro Assis, A. Etchegoyen, G. Medina-Tanco, Warner A. Miller, Onofrio A. Catalano, G. La Rosa, L. R. Wiencke, Petr Schovanek, R. Meyhandan, J. Knapp, X. Garrido, M. Ambrosio, A. Criss, A. Lopez Agüera, M. Pontz, R. Sato, B. Connolly, B. M. Baughman, Eun-Joo Ahn, N. Scharf, V. Tuci, Javier Tiffenberg, Alberto Filevich, Peter Hansen, E. D. Fraenkel, F. Guarino, John Matthews, V. M. Olmos-Gilbaja, N. Pacheco, A. Petrolini, Peter Buchholz, Dusan Mandat, H. Glass, Nicolás G. Busca, M. I. Micheletti, B. Wilczyn' Ska, Marco Aglietta, Tonia M. Venters, A. Chou, A. D. Supanitsky, D. Dornic, Hernán Asorey, A. Tamburro, I. Allekotte, F. Suarez, Thomas Hebbeker, M. Kaducak, F. Ionita, D. Tcherniakhovski, H. Schoorlemmer, T. Bäcker, A. Bellétoile, G. Decerprit, Pedro Brogueira, M. Palatka, C. J. Todero Peixoto, Rúben Conceição, Pascal Lautridou, Iuri Muniz Pepe, E. Kemp, Serguei Vorobiov, D. Kruppke-Hansen, P. W. Younk, B. E. Smith, Beatriz B. Siffert, P. Schiffer, S. Parlati, S. Schulte, T. Pinto, J. L. Navarro, B. Wundheiler, Gregory R Snow, Marcio Aparecido Muller, P. H. Kasper, D. Newton, V. H. Ponce, L. Perrone, Jiri Chudoba, E. Colombo, A. Tamashiro, G. P. Guedes, Daniel Gonzalez, D. Monnier Ragaigne, S. Harmsma, E. Strazzeri, J. C. Diaz, G. Golup, Ivor Fleck, S. Dagoret-Campagne, L. del Peral, H. Gemmeke, N. Kunka, C. Pfendner, A. Cordier, M. Unger, J. F. Valdés Galicia, I. De Mitri, J. Rodriguez Martino, G. Yuan, S. Riggi, J. Chye, G. Matthiae, Matias Tueros, J. Abraham, E. Grashorn, J. W. Cronin, Antonio Bueno, Sergio Pastor, Daniel Omar Badagnani, Nataliia Borodai, H. Wilczyn' Ski, F. Salamida, M. A. Leigui de Oliveira, R. Tcaciuc, F. Schroeder, S. J. De Jong, Y. Guardincerri, Gualberto Avila, P. Bauleo, Pierre Billoir, D. Thomas, A. Curutiu, B. Tome, A. F. Grillo, Juan Carlos D'Olivo, T. Pierog, S. Coutu, M. Nyklicek, Esteban Roulet, J. R. T. de Mello Neto, Angela V. Olinto, V. Halenka, M. Hussain, T. Karova, B. Kégl, Fabian Schmidt, F. Montanet, J. C. dos Anjos, P. L. Ghia, Michael DuVernois, M. McEwen, M. C. Maccarone, L. Voyvodic, Subir Sarkar, Alexander Kusenko, German Ros, F. Arqueros, C. Wileman, P. Necesal, D. Garcia-Pinto, R. Mussa, J. J. Beatty, Silvia Mollerach, J. Coppens, J. Chauvin, N. Fazzini, A. Segreto, Julien Aublin, Markus Roth, M. Patel, Radomir Smida, C. Delle Fratte, A. Ferrero, A. Anzalone, V. de Souza, T. Tarutina, M. Gómez Berisso, R. C. Shellard, I. Rodriguez-Cabo, Jose Chinellato, A. F. Barbosa, M. Ave, D. Nosek, R. E. Burton, A. Letessier-Selvon, H. J. Mathes, V. Verzi, H. Dembinski, G. De La Vega, Ofelia Pisanti, B. J. Whelan, D. Maurizio, J. Rodriguez Rojo, C. Aramo, Enrique Zas, Pham Ngoc Diep, O. Blanch-Bigas, A. Krieger, A. Dorofeev, C. Di Giulio, Heino Falcke, Fernando Contreras, G. Wieczorek, Marco Iarlori, J. Petrovic, S. Reucroft, M. Prouza, S. Mueller, P. Abreu, A. Della Selva, M. Videla, D. Ravignani, Ernesto Arganda, C. E. Fracchiolla, G. Farrar, L. Villaseñor, R. R. McNeil, Dariusz Gora, G. Salina, Olivier Deligny, T. Rossler, A. Lemiere, B. Fick, A. Tonachini, T. Asch, M. Gonçalves do Amaral, J. D. Swain, G. Rodriguez, M. G. Winnick, M. Platino, Marcos Santander, A. Insolia, M. Kleifges, D. Zavrtanik, L. Nožka, L. Caramete, G. Tristram, B. L. Lago, C. Aguirre, Francisco J. Blanco, F. Gomez Albarracin, V. Scherini, G. Hebrero, A. Gorgi, Z. Szadowski, S. Jiraskova, Ioana Codrina Maris, A. Menshikov, B. R. Becker, Ralph Engel, D. H. Koang, J. Ridky, Tristan Beau, A. Stutz, B. García, Mario Scuderi, APC - Astrophysique des Hautes Energies (APC - AHE), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Accélérateur Linéaire (LAL), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire SUBATECH Nantes (SUBATECH), Mines Nantes (Mines Nantes)-Université de Nantes (UN)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), APC - THEORIE, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut für theoretische Physik, Universität Hamburg (UHH)-Universität Hamburg (UHH), PIERRE AUGER, Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Nantes (UN)-Mines Nantes (Mines Nantes), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut für theoretische Physik, Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut für theoretische Physik, D'Urso, Domenico, Guarino, Fausto, Valore, Laura, and The Pierre Auger, Collaboration

Subjects
Astroparticle physics, Physics, Pierre Auger Observatory, [PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], 010308 nuclear & particles physics, Astronomy, Detector, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Auger, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Experimental High Energy Physics, 0103 physical sciences, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS
Abstract

The Pierre Auger Collaboration... K.B. Barber... J.A. Bellido... R.W. Clay... B.R. Dawson... V.C. Holmes... J. Sorokin... P. Wahrlich... B.J. Whelan... M.G. Winnick... et al.

Published
2010
Full Text
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45. Utilization of screening mammography as a preventive practice prior to initiating a population-based breast cancer screening program

Author

Francesc Macià, Francesc Ferrer, Josep M Segura, Xavier Castells, and Montserrat Casamitjana

Subjects
medicine.medical_specialty, Epidemiology, Population, Breast Neoplasms, Breast cancer screening, Breast cancer, Preventive Health Services, medicine, Humans, Mass Screening, Mammography, Family history, education, Probability, Gynecology, education.field_of_study, medicine.diagnostic_test, Screening mammography, business.industry, Public health, Middle Aged, medicine.disease, Spain, Family medicine, Educational Status, Female, business
Abstract

Factors associated with the level of utilization of screening mammography as a preventive practice were analyzed prior to initiating a population-based breast cancer screening program. A questionnaire was used to collect information about screening mammography utilization during the last 4 years among women invited to enroll in the program. Sociodemographic and health factors, and health services utilization were studied. A screening mammography in the last 4 years had been performed on 59.3% of the 8867 women interviewed. The utilization of mammography was higher among women who were younger, had a higher education level, or had previous visits to a physician (P < 0.001). The variables more strongly associated with use of screening mammography were: visit to a gynecologist and performance of a pap smear. Also associated with the utilization of screening mammography were: personal history of breast pathology, family history of breast cancer, breast self-examination, and recent visit to a general practitioner. Self-perceived health presented an inverse relation with screening mammography use (P < 0.001). The use of screening mammography appears to have increased in recent years, although inequalities persist which the breast cancer screening programs help to modulate. Mammographic frequency only would be deemed appropriate by the European guidelines in fewer than one-half of the cases.

Published
2000
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46. El panoràmic 2015

Author

Torre Jussana-Centre de Serveis a les Associacions, Consell d'Associacions de Barcelona, Observatori del Tercer Sector, Fundació Pere Tarrés, Fundació Francesc Ferrer i Guàrdia, Fundació la Caixa, Fernández, Montse, Vidal, Pau, Torre Jussana-Centre de Serveis a les Associacions, Consell d'Associacions de Barcelona, Observatori del Tercer Sector, Fundació Pere Tarrés, Fundació Francesc Ferrer i Guàrdia, Fundació la Caixa, Fernández, Montse, and Vidal, Pau

Published
2016

47. Search for CP Violating Signature of Intergalactic Magnetic Helicity in the Gamma Ray Sky

Author

Wenlei Chen, Tanmay Vachaspati, Francesc Ferrer, and Hiroyuki Tashiro

Subjects
Physics, High Energy Astrophysical Phenomena (astro-ph.HE), High Energy Physics - Theory, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Milky Way, FOS: Physical sciences, Astronomy and Astrophysics, Field strength, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Helicity, Galaxy, Magnetic field, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), High Energy Physics - Theory (hep-th), Space and Planetary Science, Magnetic helicity, Intergalactic travel, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics::Galaxy Astrophysics, Fermi Gamma-ray Space Telescope, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The existence of a cosmological magnetic field could be revealed by the effects of non-trivial helicity on large scales. We evaluate a CP odd statistic, $Q$, using gamma ray data obtained from Fermi satellite observations at high galactic latitudes to search for such a signature. Observed values of $Q$ are found to be non-zero; the probability of a similar signal in Monte Carlo simulations is $\sim 0.2\%$. Contamination from the Milky Way does not seem to be responsible for the signal since it is present even for data at very high galactic latitudes. Assuming that the signal is indeed due to a helical cosmological magnetic field, our results indicate left-handed magnetic helicity and field strength $\sim 10^{-14}~{\rm G}$ on $\sim 10~{\rm Mpc}$ scales., 5 pages. Matches published MNRAS Lett. version. For analysis tools see http://sites.physics.wustl.edu/magneticfields/wiki/index.php/Search_for_CP_violation_in_the_gamma-ray_sky

Published
2013

48. Scientific reach of multiton-scale dark matter direct detection experiments

Author

James B. Dent, Francesc Ferrer, Thomas Jacques, Jayden L. Newstead, and Lawrence M. Krauss

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Hot dark matter, Dark matter, Massive particle, Scalar field dark matter, FOS: Physical sciences, High Energy Physics - Experiment, High Energy Physics - Phenomenology, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), Isospin, Weakly interacting massive particles, Warm dark matter, Light dark matter, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The next generation of large scale WIMP direct detection experiments have the potential to go beyond the discovery phase and reveal detailed information about both the particle physics and astrophysics of dark matter. We report here on early results arising from the development of a detailed numerical code modeling the proposed DARWIN detector, involving both liquid argon and xenon targets. We incorporate realistic detector physics, particle physics and astrophysical uncertainties and demonstrate to what extent two targets with similar sensitivities can remove various degeneracies and allow a determination of dark matter cross sections and masses while also probing rough aspects of the dark matter phase space distribution. We find that, even assuming dominance of spin-independent scattering, multi-ton scale experiments still have degeneracies that depend sensitively on the dark matter mass, and on the possibility of isospin violation and inelasticity in interactions. We find that these experiments are best able to discriminate dark matter properties for dark matter masses less than around 200 GeV. In addition, and somewhat surprisingly, the use of two targets gives only a small improvement (aside from the advantage of different systematics associated with any claimed signal) in the ability to pin down dark matter parameters when compared with one target of larger exposure., Comment: 23 pages; updated to match PRD version

Published
2013
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49. The impact of the phase-space density on the indirect detection of dark matter

Author

Daniel R. Hunter and Francesc Ferrer

Subjects
High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Annihilation, COSMIC cancer database, 010308 nuclear & particles physics, Milky Way, Maxwell–Boltzmann statistics, Dark matter, Gamma ray, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Galaxy, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), Phase space, 0103 physical sciences, 010306 general physics, Astrophysics - High Energy Astrophysical Phenomena
Abstract

We study the indirect detection of dark matter when the local dark matter velocity distribution depends upon position, as expected for the Milky Way and its dwarf spheroidal satellites, and the annihilation cross-section is not purely s-wave. Using a phase-space distribution consistent with the dark matter density profile, we present estimates of cosmic and gamma-ray fluxes from dark matter annihilations. The expectations for the indirect detection of dark matter can differ significantly from the usual calculation that assumes that the velocity of the dark matter particles follows a Maxwell-Boltzmann distribution., 34 pages, 18 figures

Published
2013

50. Dark matter distributions around massive black holes: A general relativistic analysis

Author

Clifford M. Will, Francesc Ferrer, and Laleh Sadeghian

Subjects
Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, White hole, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Primordial black hole, Astrophysics, General Relativity and Quantum Cosmology (gr-qc), Charged black hole, 01 natural sciences, Astrophysics - Astrophysics of Galaxies, General Relativity and Quantum Cosmology, Black hole, Rotating black hole, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, Extremal black hole, Stellar black hole, 010303 astronomy & astrophysics, Schwarzschild radius
Abstract

The cold dark matter at the center of a galaxy will be redistributed by the presence of a massive black hole. The redistribution may be determined using an approach pioneered by Gondolo and Silk: begin with a model distribution function for the dark matter, and ``grow'' the black hole adiabatically, holding the adiabatic invariants of the motion constant. Unlike the approach of Gondolo and Silk, which adopted Newtonian theory together with ad hoc correction factors to mimic general relativistic effects, we carry out the calculation fully relativistically, using the exact Schwarzschild geometry of the black hole. We find that the density of dark matter generically vanishes at r=2R_S, not 4R_S as found by Gondolo and Silk, where R_S is the Schwarzschild radius, and that the spike very close to the black hole reaches significantly higher densities. We apply the relativistic adiabatic growth framework to obtain the final dark matter density for both cored and cusped initial distributions. Besides the implications of these results for indirect detection estimates, we show that the gravitational effects of such a dark matter spike are significantly smaller than the relativistic effects of the black hole, including frame dragging and quadrupolar effects, for stars orbiting close to the black hole that might be candidates for testing the black hole no-hair theorems., 18 pages, 5 figures, submitted to Phys. Rev D

Published
2013

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