arXiv subjects

Burt Holzman

Publications and source records attributed to Burt Holzman.

23 records · Page 2Linked to original sources

arXiv2017

HEPCloud, a New Paradigm for HEP Facilities: CMS Amazon Web Services Investigation

Historically, high energy physics computing has been performed on large purpose-built computing systems. These began as single-site compute facilities, but have evolved into the distributed computing grids used today. Recently, there has been an exponential increase in the capacity and capability of commercial clouds. Cloud resources are highly virtualized and intended to be able to be flexibly deployed for a variety of computing tasks. There is a growing nterest among the cloud providers to demonstrate the capability to perform large-scale scientific computing. In this paper, we discuss results from the CMS experiment using the Fermilab HEPCloud facility, which utilized both local Fermilab resources and virtual machines in the Amazon Web Services Elastic Compute Cloud. We discuss the planning, technical challenges, and lessons learned involved in performing physics workflows on a large-scale set of virtualized resources. In addition, we will discuss the economics and operational efficiencies when executing workflows both in the cloud and on dedicated resources.

cs.DC↗

arXiv2014

Power-aware applications for scientific cluster and distributed computing

The aggregate power use of computing hardware is an important cost factor in scientific cluster and distributed computing systems. The Worldwide LHC Computing Grid (WLCG) is a major example of such a distributed computing system, used primarily for high throughput computing (HTC) applications. It has a computing capacity and power consumption rivaling that of the largest supercomputers. The computing capacity required from this system is also expected to grow over the next decade. Optimizing the power utilization and cost of such systems is thus of great interest. A number of trends currently underway will provide new opportunities for power-aware optimizations. We discuss how power-aware software applications and scheduling might be used to reduce power consumption, both as autonomous entities and as part of a (globally) distributed system. As concrete examples of computing centers we provide information on the large HEP-focused Tier-1 at FNAL, and the Tigress High Performance Computing Center at Princeton University, which provides HPC resources in a university context.

physics.comp-ph↗

arXiv2004

Rapidity and k_T dependence of HBT correlations in Au+Au collisions at 200 GeV with PHOBOS

Two-particle correlations of identical charged pion pairs from Au+Au collisions at sqrt(s_NN) = 200 GeV were measured by the PHOBOS experiment at RHIC. Data for the most central (0--15%) events were analyzed with Bertsch-Pratt (BP) and Yano-Koonin-Podgoretskii (YKP) parameterizations using pairs with rapidities of 0.4 < y < 1.3 and transverse momenta 0.1 < k_T < 1.4 GeV/c. The Bertsch-Pratt radii decrease as a function of pair transverse momentum. The pair rapidity Y_pipi roughly scales with the source rapidity Y_YKP, indicating strong dynamical correlations.

nucl-ex↗

arXiv2001

Systematic Study of Au-Au Collisions with AGS Experiment E917

The systematics of baryon stopping and strange particle production have been studied in Au+Au collisions at 6, 8, and 10.8 GeV per nucleon with AGS experiment E917. In particular, the systematic behavior of the proton yields, phi meson production, and the yields of antilambdas and antiprotons are examined as functions of beam energy and centrality.

nucl-ex↗

arXiv1999

HBT Studies with E917 at the AGS: A Status Report

Two-particle correlations between pions in Au+Au collisions have been measured at beam kinetic energies of 6, 8, and 10.8 GeV/u at the Alternating Gradient Synchrotron (AGS) over a wide range of rapidities using a magnetic spectrometer. The data have been analyzed in the Hanbury-Brown and Twiss (HBT) framework to extract source parameters. The event-by-event orientation of the reaction plane has also been measured using a scintillator hodoscope at far forward rapidities, and beam vertexing detectors upstream of the target. A preliminary analysis of the dependence of the source parameters on the reaction plane is presented.

nucl-ex↗