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A dynamic application-driven data communication strategy

Paul van der Mark, Lex Wolters, Gerard Cats
2004 Proceedings of the 18th annual international conference on Supercomputing - ICS '04  
We discus a novel strategy, called Halo on Demand, which dynamically drives the communication between the processors by examining the content of the data at runtime in order to reduce communication costs  ...  With an extensive performance analysis of the execution of the model we show that our strategy can decrease communication time and thus decrease total execution time.  ...  Figure 6 : 6 Inspector-Executor Transformed loop show the effect of the Halo on Demand strategy on the total execution times we have calculated the speedup of the model with and without the use of the  ... 
doi:10.1145/1006209.1006231 dblp:conf/ics/MarkWC04 fatcat:mqxoj2bicbdh7fy4tztlte6pgy

THE ROCKSTAR PHASE-SPACE TEMPORAL HALO FINDER AND THE VELOCITY OFFSETS OF CLUSTER CORES

Peter S. Behroozi, Risa H. Wechsler, Hao-Yi Wu
2012 Astrophysical Journal  
using K-Space Topologically Adaptive Refinement).  ...  A previous paper (Knebe et al 2011) has shown Rockstar to have class-leading recovery of halo properties; we expand on these comparisons with more tests and higher-resolution simulations.  ...  This is critical for comparison with galaxy statistics in dense regimes, and paves the way for direct comparisons of clustering between simulations and observations in the regions where the unknown effects  ... 
doi:10.1088/0004-637x/762/2/109 fatcat:engjhehlujg3tiwt7leefy7kqe

Blocking Versus Non-Blocking Halo Exchange [article]

Anthony Bourached
2017 arXiv   pre-print
Work-Communication overlap can be used to improve the performance of the non-blocking routine. Development and benchmarking were conducted on the UK national supercomputer, ARCHER.  ...  This report describes the design, implementation and analysis of a non-blocking halo exchange routine as an alternative to the blocking halo exchange routine in the lattice Boltzmann code Ludwig.  ...  Thus, it is the time spent in halo communication which is used for analysis in each case, with the exception of the work-communication overlap benchmarks as explained in chapter 6.  ... 
arXiv:1709.06175v1 fatcat:rkvmpf2xrvcjjkzfflzumvlhui

Two-neutron halo structure of F31

N. Michel, J. G. Li, F. R. Xu, W. Zuo
2020 Physical Review C  
For this, one-nucleon densities, root-mean square radii and correlation densities are calculated in neutron-rich fluorine isotopes.  ...  It is then suggested that ^31F exhibits a two-neutron halo structure, built from both continuum coupling and nucleon-nucleon correlations.  ...  FIG. 3 . 3 Correlation densities (in fm −6 ) of the bound 27,29,31 F isotopes calculated with GSM using the EFT interaction as a function of r (in fm).  ... 
doi:10.1103/physrevc.101.031301 fatcat:ha7rtqqd2nhbjctyv5k3j2hzdi

Light-cone distortion of the clustering and abundance of massive galaxies at high redshifts

Joseph A. Muñoz, Abraham Loeb
2008 Monthly notices of the Royal Astronomical Society  
The effect of observing a survey volume along the light-cone must be considered in the regime where the mass function of galaxies varies exponentially with redshift.  ...  Moreover, the statistical moments of the count of galaxies calculated ignoring the light-cone effect, deviate from the actual values.  ...  AC K N OW L E D G M E N T S We would like to thank Rychard Bouwens and Dan Stark for useful discussions. JAM acknowledges support from a National Science Foundation Graduate Research Fellowship.  ... 
doi:10.1111/j.1365-2966.2008.13210.x fatcat:ebd3uccwefd3jf72rt3ug5ssiq

Large scale pressure fluctuations and the Sunyaev-Zel'dovich effect

Asantha Cooray
2000 Physical Review D, Particles and fields  
The Sunyaev-Zel'dovich (SZ) effect associated with pressure fluctuations of the large scale structure gas distribution will be probed with current and upcoming wide-field small angular scale cosmic microwave  ...  They provide a lower limit to the SZ effect due to large scale structure in the absence of massive collapsed halos.  ...  ACKNOWLEDGMENTS The author greatfully thanks Wayne Hu for useful discussions and helpful suggestions that led to the calculations presented in this paper.  ... 
doi:10.1103/physrevd.62.103506 fatcat:ucnhq3vjxfgvfcrf6ljuursmxa

Theoretical Study of Nuclear Density Distributions and Elastic Electron Scattering form Factors for Some Halo Nuclei

2017 Iraqi Journal of Science  
The local scale transformation (LST) are used to improve the performance radial wave function of harmonic-oscillator wave function in order to generate the long tail behavior appeared in matter density  ...  Keywords: halo nuclei, nuclear density distributions, elastic electron scattering form factors, root-mean square radii. ‫  ...  The proton and neutron density distributions are calculated with acceptable results using LST for 6,8 He and 11 Li but with overestimated rms radii [12] .  ... 
doi:10.24996/ijs.2017.58.4b.13 fatcat:bcay3qjwtnfdngqo6rwgrdm6bu

Weak Lensing by Large-Scale Structure: A Dark Matter Halo Approach

Asantha Cooray, Wayne Hu, Jordi Miralda-Escudé
2000 Astrophysical Journal  
We determine the convergence power spectrum as a function of the maximum halo mass and so provide the means to interpret results from surveys that lack high mass halos either through selection criteria  ...  We show how the expected signal from large-scale structure arises from the contributions from and correlations between individual halos.  ...  When calculated with hyper-extended perturbation theory (HEPT, see Hui 1999) but using the halo power spectrum instead of non-linear density power spectrum, the skewness decreased by a factor of ∼ 2.5  ... 
doi:10.1086/312696 pmid:10828996 fatcat:2jhkitvlpnakpbhgcv443gjluy

Group Identification in N-Body Simulations: SKID and DENMAX Versus Friends-of-Friends [article]

M. Goetz Harvard-Smithsonian Center for Astrophysics, Physics Department, Brown University)
1998 arXiv   pre-print
Three popular algorithms (FOF, DENMAX, and SKID) to identify halos in cosmological N-body simulations are compared with each other and with the predicted mass function from Press-Schechter theory.  ...  For many parameter values, DENMAX and SKID have the tendency to include in the halos particles at large distances from the halo center with low peculiar velocities.  ...  Program for making the N-body simulation and group identification codes available to the cosmology community on the World Wide Web.  ... 
arXiv:astro-ph/9811393v1 fatcat:vki62mbckfak5dkjkmto5knp2u

Including beyond-linear halo bias in halo models

A J Mead, L Verde
2021 Monthly notices of the Royal Astronomical Society  
We measure this correction using data from N-body simulations and demonstrate that it can boost power in the two-halo term by a factor of ∼2 at scales k ∼ 0.7 hMpc−1, with the exact magnitude of the boost  ...  determined by the specific pair of fields in the two-point function.  ...  The MULTIDARK Database used in this paper and  ... 
doi:10.1093/mnras/stab748 fatcat:5an5ztc3ffefxcvuot2essy6da

Pre-asymptotic behavior of single-particle overlap integrals of non-Borromean two-neutron halos

N. K. Timofeyuk, L. D. Blokhintsev, J. A. Tostevin
2003 Physical Review C  
This will lead to surface and preasymptotic deviations from the overlap functions calculated using potential models, out to large distances.  ...  Most theoretical analyses of experimental data assume that these overlaps can be calculated using simple two-body potential models.  ...  We have calculated the tails of the effective potentials V e f f (r) for different c 10 using Eq. ͑10͒.  ... 
doi:10.1103/physrevc.68.021601 fatcat:ug5dfjc7aveuhdqp4yft4cs7j4

Including beyond-linear halo bias in halo models [article]

Alexander Mead, Licia Verde
2021 arXiv   pre-print
We measure this correction using data from N-body simulations and demonstrate that it can boost power in the two-halo term by a factor of ∼2 at scales k∼0.7 h Mpc^-1, with the exact magnitude of the boost  ...  determined by the specific pair of fields in the two-point function.  ...  The MULTIDARK Database used in this paper and  ... 
arXiv:2011.08858v2 fatcat:bxfzoz2j3bewtejh6jfwke3dlq

ANALYZING AND VISUALIZING COSMOLOGICAL SIMULATIONS WITH ParaView

Jonathan Woodring, Katrin Heitmann, James Ahrens, Patricia Fasel, Chung-Hsing Hsu, Salman Habib, Adrian Pope
2011 Astrophysical Journal Supplement Series  
In combination with many other functionalities already existing within ParaView, such as histogram routines or interfaces to Python, this enhanced version enables fast, interactive, and convenient analyses  ...  The new features include particle readers and a very efficient halo finder which identifies friends-of-friends halos and determines common halo properties.  ...  Together with manipulation and analysis tools such as a calculator and binning routines, we believe that ParaView will be a very valuable new tool for the cosmology community.  ... 
doi:10.1088/0067-0049/195/1/11 fatcat:wwfwaq3oyfal7ptz75w4stpe74

The three-point correlation function in cosmology

Masahiro Takada, Bhuvnesh Jain
2003 Monthly notices of the Royal Astronomical Society  
We use the halo clustering model to analytically calculate the three-point correlation function (3PCF) for general cosmological fields.  ...  We work in real space, where higher order correlation functions on small scales are easier to measure and interpret, but halo model calculations get rapidly intractable.  ...  The small-scale slope of the one-halo term is determined by the combined effects of the NFW profile, the mass function and the halo concentration in the halo model calculation.  ... 
doi:10.1046/j.1365-8711.2003.06321.x fatcat:nowaudc62fdu3f6spcfj2q72gm

Spherical collapse inνΛCDM

Marilena LoVerde
2014 Physical Review D  
We propose one way of handling this and compute the correction to the halo mass function within this framework.  ...  For ∑ m_ν i < 0.3eV, our prescription for the halo abundance is only ∼< 15% different than the standard calculation.  ...  The halo abundance The calculations of the collapse threshold from §III A can be used to estimate the effects massive neutrinos on the halo mass function.  ... 
doi:10.1103/physrevd.90.083518 fatcat:oy2hdabasrhqdanznz3njhj72u
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