Records |
Author |
Wagner, C.; Verde, L.; Boubekeur, L. |
Title |
N-body simulations with generic non-Gaussian initial conditions I: power spectrum and halo mass function |
Type |
Journal Article |
Year |
2010 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
10 |
Issue |
10 |
Pages |
022 - 24pp |
Keywords |
power spectrum; cosmological simulations; initial conditions and eternal universe; galaxy clusters |
Abstract |
We address the issue of setting up generic non-Gaussian initial conditions for N-body simulations. We consider inflationary-motivated primordial non-Gaussianity where the perturbations in the Bardeen potential are given by a dominant Gaussian part plus a non-Gaussian part specified by its bispectrum. The approach we explore here is suitable for any bispectrum, i.e. it does not have to be of the so-called separable or factorizable form. The procedure of generating a non-Gaussian field with a given bispectrum (and a given power spectrum for the Gaussian component) is not univocal, and care must be taken so that higher-order corrections do not leave a too large signature on the power spectrum. This is so far a limiting factor of our approach. We then run N-body simulations for the most popular inflationary-motivated non-Gaussian shapes. The halo mass function and the non-linear power spectrum agree with theoretical analytical approximations proposed in the literature, even if they were so far developed and tested only for a particular shape (the local one). We plan to make the simulations outputs available to the community via the non-Gaussian simulations comparison project web site http://icc.ub.edu/similar to liciaverde/NGSCP.html. |
Address |
[Wagner, Christian; Verde, Licia] Univ Barcelona, ICCUB IEEC, E-08028 Barcelona, Spain, Email: cwagner@icc.ub.edu |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000283577600013 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, ascending order (up)](img/sort_asc.gif) |
no |
Call Number |
IFIC @ elepoucu @ |
Serial |
339 |
Permanent link to this record |
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Author |
Marco-Hernandez, R. |
Title |
Development of a beam test telescope based on the Alibava readout system |
Type |
Journal Article |
Year |
2011 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
Volume |
6 |
Issue |
|
Pages |
C01002 - 7pp |
Keywords |
Particle tracking detectors; Data acquisition circuits; Front-end electronics for detector readout; Digital electronic circuits |
Abstract |
A telescope for a beam test have been developed as a result of a collaboration among the University of Liverpool, Centro Nacional de Microelectronica (CNM) of Barcelona and Instituto de Fisica Corpuscular (IFIC) of Valencia. This system is intended to carry out both analogue charge collection and spatial resolution measurements with different types of microstrip or pixel silicon detectors in a beam test environment. The telescope has four XY measurement as well as trigger planes (XYT board) and it can accommodate up to twelve devices under test (DUT board). The DUT board uses two Beetle ASICs for the readout of chilled silicon detectors. The board could operate in a self-triggering mode. The board features a temperature sensor and it can be mounted on a rotary stage. A peltier element is used for cooling the DUT. Each XYT board measures the track space points using two silicon strip detectors connected to two Beetle ASICs. It can also trigger on the particle tracks in the beam test. The board includes a CPLD which allows for the synchronization of the trigger signal to a common clock frequency, delaying and implementing coincidence with other XYT boards. An Alibava mother board is used to read out and to control each XYT/DUT board from a common trigger signal and a common clock signal. The Alibava board has a TDC on board to have a time stamp of each trigger. The data collected by each Alibava board is sent to a master card by means of a local data/address bus following a custom digital protocol. The master board distributes the trigger, clock and reset signals. It also merges the data streams from up to sixteen Alibava boards. The board has also a test channel for testing in a standard mode a XYT or DUT board. This board is implemented with a Xilinx development board and a custom patch board. The master board is connected with the DAQ software via 100M Ethernet. Track based alignment software has also been developed for the data obtained with the DAQ software. |
Address |
[Marco-Hernandez, R.; Alibava Collaboration] CSIC UV, Inst Fis Corpuscular, E-46980 Paterna, Valencia, Spain, Email: rmarco@ific.uv.es |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1748-0221 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000291345600007 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, ascending order (up)](img/sort_asc.gif) |
no |
Call Number |
IFIC @ elepoucu @ |
Serial |
644 |
Permanent link to this record |
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Author |
Yamagata-Sekihara, J.; Oset, E. |
Title |
V P gamma radiative decay of resonances dynamically generated from the vector meson-vector meson interaction |
Type |
Journal Article |
Year |
2010 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
690 |
Issue |
4 |
Pages |
376-381 |
Keywords |
Local hidden gauge; Radiative decays; Vector mesons; Dynamically generated resonances |
Abstract |
We evaluate the radiative decay into a vector, a pseudoscalar and a photon of several resonances dynamically generated from the vector-vector interaction. The process proceeds via the decay of one of the vector components into a pseudoscalar and a photon, which have an invariant mass distribution very different from phase space as a consequence of the two vector structure of the resonances. Experimental work along these lines should provide useful information on the nature of these resonances. |
Address |
[Yamagata-Sekihara, J.] Univ Valencia, Ctr Mixto, CSIC, Inst Invest Paterna,Dept Fis Teor, Valencia 46071, Spain, Email: yamagata@ific.uv.es |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-2693 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000279835300008 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, ascending order (up)](img/sort_asc.gif) |
no |
Call Number |
IFIC @ elepoucu @ |
Serial |
408 |
Permanent link to this record |
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Author |
Mendez, V.; Amoros, G.; Garcia, F.; Salt, J. |
Title |
Emergent algorithms for replica location and selection in data grid |
Type |
Journal Article |
Year |
2010 |
Publication |
Future Generation Computer Systems |
Abbreviated Journal |
Futur. Gener. Comp. Syst. |
Volume |
26 |
Issue |
7 |
Pages |
934-946 |
Keywords |
Grid computing; Algorithms; Optimization methods; Artificial intelligence |
Abstract |
Grid infrastructures for e-Science projects are growing in magnitude terms. Improvements in data Grid replication algorithms may be critical in many of these infrastructures. This paper shows a decentralized replica optimization service, providing a general Emergent Artificial Intelligence (EAI) algorithm for the problem definition. Our aim is to set up a theoretical framework for emergent heuristics in Grid environments. Further, we describe two EAI approaches, the Particle Swarm Optimization PSO-Grid Multiswarm Federation and the Ant Colony Optimization ACO-Grid Asynchronous Colonies Optimization replica optimization algorithms, with some examples. We also present extended results with best performance and scalability features for PSO-Grid Multiswarrn Federation. |
Address |
[Mendez Munoz, Victor; Amoros Vicente, Gabriel; Salt Cairols, Jose] CSIC, Grid & E Sci Grp, Inst Fis Corpuscular IFIC, Mixed Inst, E-46071 Valencia, Spain, Email: vmendez@ific.uv.es |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0167-739x |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000279804200004 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, ascending order (up)](img/sort_asc.gif) |
no |
Call Number |
IFIC @ elepoucu @ |
Serial |
411 |
Permanent link to this record |
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Author |
Albertus, C.; Hernandez, E.; Nieves, J. |
Title |
Hyperfine mixing in electromagnetic decay of doubly heavy bc baryons |
Type |
Journal Article |
Year |
2010 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
690 |
Issue |
3 |
Pages |
265-271 |
Keywords |
Hyperfine mixing; Double heavy bc baryons |
Abstract |
We investigate the role of hyperfine mixing in the electromagnetic decay of ground state doubly heavy bc baryons. As in the case of a previous calculation on b -> c semileptonic decays of doubly heavy baryons, we find large corrections to the electromagnetic decay widths due to this mixing. Contrary to the weak case just mentioned, we find here that one cannot use electromagnetic width relations obtained in the infinite heavy quark mass limit to experimentally extract information on the admixtures in a model independent way. |
Address |
[Albertus, C.; Hernandez, E.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: gajatee@usal.es |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-2693 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000279388800012 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, ascending order (up)](img/sort_asc.gif) |
no |
Call Number |
IFIC @ elepoucu @ |
Serial |
416 |
Permanent link to this record |