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Author Giare, W.; Renzi, F.; Mena, O.; Di Valentino, E.; Melchiorri, A. url  doi
openurl 
  Title Is the Harrison-Zel'dovich spectrum coming back? ACT preference for n(s) similar to 1 and its discordance with Planck Type Journal Article
  Year 2023 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal Mon. Not. Roy. Astron. Soc.  
  Volume 521 Issue 2 Pages 2911-2918  
  Keywords cosmological parameters; inflation; cosmology: observations; cosmology: theory  
  Abstract The Data Release 4 of the Atacama Cosmology Telescope (ACT) shows an agreement with an Harrison-Zel'dovich primordial spectrum (n(s) = 1.009 +/- 0.015), introducing a tension with a significance of 99.3 per cent Confidence Level (CL) with the results from the Planck satellite. The discrepancy on the value of the scalar spectral index is neither alleviated with the addition of large scale structure information nor with the low multipole polarization data. We discuss possible avenues to alleviate the tension relying on either neglecting polarization measurements from ACT or in extending different sectors of the theory.  
  Address [Giare, William] Ctr Nazl INFN Studi Avanzati, Galileo Galileo Inst Theoret Phys, Largo Enr Fermi 2, I-50125 Florence, Italy, Email: william.giare@gmail.com  
  Corporate Author Thesis  
  Publisher Oxford Univ Press Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000957248500013 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5510  
Permanent link to this record
 

 
Author Schiavone, T.; Montani, G.; Bombacigno, F. url  doi
openurl 
  Title f(R) gravity in the Jordan frame as a paradigm for the Hubble tension Type Journal Article
  Year 2023 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal Mon. Not. Roy. Astron. Soc.  
  Volume 522 Issue 1 Pages L72-L77  
  Keywords supernovae: general; galaxies: distances and redshifts; cosmological parameters; dark energy; cosmology: theory  
  Abstract We analyse the f(R) gravity in the so-called Jordan frame, as implemented to the isotropic Universe dynamics. The goal of the present study is to show that according to recent data analyses of the supernovae Ia Pantheon sample, it is possible to account for an effective redshift dependence of the Hubble constant. This is achieved via the dynamics of a non-minimally coupled scalar field, as it emerges in the f(R) gravity. We face the question both from an analytical and purely numerical point of view, following the same technical paradigm. We arrive to establish that the expected decay of the Hubble constant with the redshift z is ensured by a form of the scalar field potential, which remains essentially constant for z less than or similar to 0.3, independently if this request is made a priori, as in the analytical approach, or obtained a posteriori, when the numerical procedure is addressed. Thus, we demonstrate that an f(R) dark energy model is able to account for an apparent variation of the Hubble constant due to the rescaling of the Einstein constant by the f(R) scalar mode.  
  Address [Schiavone, Tiziano] Univ Pisa, Dept Phys Fermi, Largo Bruno Pontecorvo 3, I-56127 Pisa, Italy, Email: tschiavone@fc.ul.pt  
  Corporate Author Thesis  
  Publisher Oxford Univ Press Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001066034100015 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5672  
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Author de los Rios, M.; Petac, M.; Zaldivar, B.; Bonaventura, N.R.; Calore, F.; Iocco, F. url  doi
openurl 
  Title Determining the dark matter distribution in simulated galaxies with deep learning Type Journal Article
  Year 2023 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal Mon. Not. Roy. Astron. Soc.  
  Volume 525 Issue 4 Pages 6015-6035  
  Keywords methods: data analysis; software: simulations; galaxies: general; galaxies: haloes; dark matter  
  Abstract We present a novel method of inferring the dark matter (DM) content and spatial distribution within galaxies, using convolutional neural networks (CNNs) trained within state-of-the-art hydrodynamical simulations (Illustris-TNG100). Within the controlled environment of the simulation, the framework we have developed is capable of inferring the DM mass distribution within galaxies of mass similar to 10(11)-10(13)M(circle dot) from the gravitationally baryon-dominated internal regions to the DM-rich, baryon-depleted outskirts of the galaxies, with a mean absolute error always below approximate to 0.25 when using photometrical and spectroscopic information. With respect to traditional methods, the one presented here also possesses the advantages of not relying on a pre-assigned shape for the DM distribution, to be applicable to galaxies not necessarily in isolation, and to perform very well even in the absence of spectroscopic observations.  
  Address [de los Rios, Martin] Univ Estadual Paulista, ICTP South Amer Inst Fundamental Res, Inst Fis Teor, BR-01140070 Sao Paulo, SP, Brazil, Email: fabio.iocco.astro@gmail.com  
  Corporate Author Thesis  
  Publisher Oxford Univ Press Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001072112100006 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5707  
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Author SCiMMA and SNEWS Collaborations (Baxter, A.L. et al); Colomer, M. doi  openurl
  Title Collaborative experience between scientific software projects using Agile Scrum development Type Journal Article
  Year 2022 Publication Software-Practice & Experience Abbreviated Journal Softw.-Pract. Exp.  
  Volume 52 Issue Pages 2077-2096  
  Keywords Agile; cyberinfrastructure; multimessenger astrophysics; scientific computing; software development  
  Abstract Developing sustainable software for the scientific community requires expertise in software engineering and domain science. This can be challenging due to the unique needs of scientific software, the insufficient resources for software engineering practices in the scientific community, and the complexity of developing for evolving scientific contexts. While open-source software can partially address these concerns, it can introduce complicating dependencies and delay development. These issues can be reduced if scientists and software developers collaborate. We present a case study wherein scientists from the SuperNova Early Warning System collaborated with software developers from the Scalable Cyberinfrastructure for Multi-Messenger Astrophysics project. The collaboration addressed the difficulties of open-source software development, but presented additional risks to each team. For the scientists, there was a concern of relying on external systems and lacking control in the development process. For the developers, there was a risk in supporting a user-group while maintaining core development. These issues were mitigated by creating a second Agile Scrum framework in parallel with the developers' ongoing Agile Scrum process. This Agile collaboration promoted communication, ensured that the scientists had an active role in development, and allowed the developers to evaluate and implement the scientists' software requirements. The collaboration provided benefits for each group: the scientists actuated their development by using an existing platform, and the developers utilized the scientists' use-case to improve their systems. This case study suggests that scientists and software developers can avoid scientific computing issues by collaborating and that Agile Scrum methods can address emergent concerns.  
  Address [Baxter, Amanda L.; Clark, Michael; Kopec, Abigail; Lang, Rafael F.; Li, Shengchao; Linvill, Mark W.; Milisavljevic, Danny; Weil, Kathryn E.] Purdue Univ, Dept Phys & Astron, W Lafayette, IN 47907 USA, Email: adepoian@purdue.edu;  
  Corporate Author Thesis  
  Publisher Wiley Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0038-0644 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000830363800001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5305  
Permanent link to this record
 

 
Author Ferrer-Sanchez, A.; Martin-Guerrero, J.; Ruiz de Austri, R.; Torres-Forne, A.; Font, J.A. url  doi
openurl 
  Title Gradient-annihilated PINNs for solving Riemann problems: Application to relativistic hydrodynamics Type Journal Article
  Year 2024 Publication Computer Methods in Applied Mechanics and Engineering Abbreviated Journal Comput. Meth. Appl. Mech. Eng.  
  Volume 424 Issue Pages 116906 - 18pp  
  Keywords Riemann problem; Euler equations; Machine learning; Neural networks; Relativistic hydrodynamics  
  Abstract We present a novel methodology based on Physics-Informed Neural Networks (PINNs) for solving systems of partial differential equations admitting discontinuous solutions. Our method, called Gradient-Annihilated PINNs (GA-PINNs), introduces a modified loss function that forces the model to partially ignore high-gradients in the physical variables, achieved by introducing a suitable weighting function. The method relies on a set of hyperparameters that control how gradients are treated in the physical loss. The performance of our methodology is demonstrated by solving Riemann problems in special relativistic hydrodynamics, extending earlier studies with PINNs in the context of the classical Euler equations. The solutions obtained with the GA-PINN model correctly describe the propagation speeds of discontinuities and sharply capture the associated jumps. We use the relative l(2) error to compare our results with the exact solution of special relativistic Riemann problems, used as the reference ''ground truth'', and with the corresponding error obtained with a second-order, central, shock-capturing scheme. In all problems investigated, the accuracy reached by the GA-PINN model is comparable to that obtained with a shock-capturing scheme, achieving a performance superior to that of the baseline PINN algorithm in general. An additional benefit worth stressing is that our PINN-based approach sidesteps the costly recovery of the primitive variables from the state vector of conserved variables, a well-known drawback of grid-based solutions of the relativistic hydrodynamics equations. Due to its inherent generality and its ability to handle steep gradients, the GA-PINN methodology discussed in this paper could be a valuable tool to model relativistic flows in astrophysics and particle physics, characterized by the prevalence of discontinuous solutions.  
  Address [Ferrer-Sanchez, Antonio; Martin-Guerrero, JoseD.] ETSE UV, Elect Engn Dept, IDAL, Avgda Univ S-N, Valencia 46100, Spain, Email: Antonio.Ferrer-Sanchez@uv.es  
  Corporate Author Thesis  
  Publisher Elsevier Science Sa Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0045-7825 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001221797400001 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 6126  
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Author Villaescusa-Navarro, F. et al; Villanueva-Domingo, P. url  doi
openurl 
  Title The CAMELS Multifield Data Set: Learning the Universe's Fundamental Parameters with Artificial Intelligence Type Journal Article
  Year 2022 Publication Astrophysical Journal Supplement Series Abbreviated Journal Astrophys. J. Suppl. Ser.  
  Volume 259 Issue 2 Pages 61 - 14pp  
  Keywords  
  Abstract We present the Cosmology and Astrophysics with Machine Learning Simulations (CAMELS) Multifield Data set (CMD), a collection of hundreds of thousands of 2D maps and 3D grids containing many different properties of cosmic gas, dark matter, and stars from more than 2000 distinct simulated universes at several cosmic times. The 2D maps and 3D grids represent cosmic regions that span similar to 100 million light-years and have been generated from thousands of state-of-the-art hydrodynamic and gravity-only N-body simulations from the CAMELS project. Designed to train machine-learning models, CMD is the largest data set of its kind containing more than 70 TB of data. In this paper we describe CMD in detail and outline a few of its applications. We focus our attention on one such task, parameter inference, formulating the problems we face as a challenge to the community. We release all data and provide further technical details at https://camels-multifield-dataset.readthedocs.io.  
  Address [Villaescusa-Navarro, Francisco; Nicola, Andrina; Spergel, David N.; Matilla, Jose Manuel Zorrilla; Shao, Helen] Princeton Univ, Dept Astrophys Sci, Peyton Hall, Princeton, NJ 08544 USA, Email: villaescusa.francisco@gmail.com  
  Corporate Author Thesis  
  Publisher IOP Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0067-0049 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000780035300001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5194  
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Author Villaescusa-Navarro, F. et al; Villanueva-Domingo, P. url  doi
openurl 
  Title The CAMELS Project: Public Data Release Type Journal Article
  Year 2023 Publication Astrophysical Journal Supplement Series Abbreviated Journal Astrophys. J. Suppl. Ser.  
  Volume 265 Issue 2 Pages 54 - 14pp  
  Keywords Cosmology; Hydrodynamical simulations; Astrostatistics; Galaxy formation  
  Abstract The Cosmology and Astrophysics with Machine Learning Simulations (CAMELS) project was developed to combine cosmology with astrophysics through thousands of cosmological hydrodynamic simulations and machine learning. CAMELS contains 4233 cosmological simulations, 2049 N-body simulations, and 2184 state-of-the-art hydrodynamic simulations that sample a vast volume in parameter space. In this paper, we present the CAMELS public data release, describing the characteristics of the CAMELS simulations and a variety of data products generated from them, including halo, subhalo, galaxy, and void catalogs, power spectra, bispectra, Lya spectra, probability distribution functions, halo radial profiles, and X-rays photon lists. We also release over 1000 catalogs that contain billions of galaxies from CAMELS-SAM: a large collection of N-body simulations that have been combined with the Santa Cruz semianalytic model. We release all the data, comprising more than 350 terabytes and containing 143,922 snapshots, millions of halos, galaxies, and summary statistics. We provide further technical details on how to access, download, read, and process the data at .  
  Address [Villaescusa-Navarro, Francisco; Genel, Shy; Angles-Alcazar, Daniel; Hassan, Sultan; Pisani, Alice; Wong, Kaze W. K.; Coulton, William R.; Steinwandel, Ulrich P.; Spergel, David N.; Burkhart, Blakesley; Wandelt, Benjamin; Somerville, Rachel S.; Bryan, Greg L.; Li, Yin] Flatiron Inst, Ctr Computat Astrophys, 162 5th Ave, New York, NY 10010 USA, Email: camel.simulations@gmail.com  
  Corporate Author Thesis  
  Publisher IOP Publishing Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0067-0049 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000964876300001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5525  
Permanent link to this record
 

 
Author Liang, J.; Singh, B.; McCutchan, E.A.; Dillmann, I.; Birch, M.; Sonzogni, A.A.; Huang, X.; Kang, M.; Wang, J.; Mukherjee, G.; Banerjee, K.; Abriola, D.; Algora, A.; Chen, A.A.; Johnson, T.D.; Miernik, K. doi  openurl
  Title Compilation and Evaluation of Beta-Delayed Neutron Emission Probabilities and Half-Lives for Z > 28 Precursors Type Journal Article
  Year 2020 Publication Nuclear Data Sheets Abbreviated Journal Nucl. Data Sheets  
  Volume 168 Issue Pages 1-116  
  Keywords  
  Abstract We present a compilation and evaluation of experimental beta-delayed neutron emission probabilities (P-n) and half-lives (T-1/2) for known or potential beta-delayed neutron precursors with atomic number Z > 28 (Cu-73 – Fr-233). This article includes the recommended values of both of these quantities, together with a compilation of experimental measurements when available. Some notable cases, as well as proposed standards for beta-delayed neutron measurements are also discussed. Evaluated data has also been compared to systematics using three different approaches. The literature cut-off date for this work is August 15, 2020.  
  Address [Liang, J.; Singh, B.; Birch, M.; Chen, A. A.] McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada, Email: balraj@mcmaster.ca  
  Corporate Author Thesis  
  Publisher Academic Press Inc Elsevier Science Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0090-3752 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000575888800001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4560  
Permanent link to this record
 

 
Author Dimitriou, P. et al; Tain, J.L.; Algora, A. url  doi
openurl 
  Title Development of a Reference Database for Beta-Delayed Neutron Emission Type Journal Article
  Year 2021 Publication Nuclear Data Sheets Abbreviated Journal Nucl. Data Sheets  
  Volume 173 Issue Pages 144-238  
  Keywords  
  Abstract Beta-delayed neutron emission is important for nuclear structure and astrophysics as well as for reactor applications. Significant advances in nuclear experimental techniques in the past two decades have led to a wealth of new measurements that remain to be incorporated in the databases. We report on a coordinated effort to compile and evaluate all the available beta-delayed neutron emission data. The different measurement techniques have been assessed and the data have been compared with semi-microscopic and microscopic-macroscopic models. The new microscopic database has been tested against aggregate total delayed neutron yields, time-dependent group parameters in 6-and 8-group re-presentation, and aggregate delayed neutron spectra. New recommendations of macroscopic delayed-neutron data for fissile materials of interest to applications are also presented.  
  Address [Dimitriou, P.; Verpelli, M.] IAEA, NAPC Nucl Data Sect, A-1400 Vienna, Austria, Email: p.dimitriou@iaea.org  
  Corporate Author Thesis  
  Publisher Academic Press Inc Elsevier Science Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0090-3752 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000647012500006 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4828  
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Author Clausse, A.; Soto, L.; Tarifeño-Saldivia, A. doi  openurl
  Title Influence of the Anode Length on the Neutron Emission of a 50 J Plasma Focus: Modeling and Experiment Type Journal Article
  Year 2015 Publication IEEE Transactions on Plasma Science Abbreviated Journal IEEE Trans. Plasma Sci.  
  Volume 43 Issue 2 Pages 629-636  
  Keywords Anode; fusion neutrons; modeling; plasma focus (PF); plasma pinch  
  Abstract A comprehensive set of electric data measured in a small plasma focus (PF) device of 50 J correlated with the corresponding neutron emissions is taken as the base for developing a semiempirical model of the current sheet dynamics and the neutron yield. The model is able to explain the dependence of the neutron yield with the pressure and anode length with good accuracy, and suggests a physical interpretation of the drive parameter commonly used in PF design.  
  Address [Clausse, Alejandro] Natl Univ Cent Buenos Aires, Natl Atom Energy Commiss, Natl Sci & Tech Res Council, RA-7000 Tandil, Argentina, Email: clausse@exa.unicen.edu.ar;  
  Corporate Author Thesis  
  Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0093-3813 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000352084400021 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2186  
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