59906581
A Tutorial on the Construction of High-Performance Resolution/Paramodulation Systems
Over the past 25 years, researchers have written numerous deduction systems based on resolution and paramodulation. Of these systems, a very few have been capable of generating and maintaining a formula database'' containing more than just a few thousand clauses. These few systems were used to explore mechanisms for rapidly extracting limited subsets of relevant'' clauses. We have written this tutorial to reflect some of the best ideas that have emerged and to cast them in a form that makes them easily accessible to students wishing to write their own high-performance systems. 4 refs.
122473897
OTTER Experiments Pertinent to CADE-10
This Argonne report serves as a companion to our CADE-10 paper. To fulfill promises made in that paper, we include here detailed proofs in clause notation, input files compatible with OTTER, and explanations for our choice of approach. We also include certain of the original and unpublished proofs (of Winker) that answered four open questions, two in equivalent calculus and two in the R-calculus. The organization parallels that of our CADE-10 paper. 34 refs.
118418646
Off-line radiometric analysis of Planck-LFI data
The Planck Low Frequency Instrument (LFI) is an array of 22 pseudo-correlation radiometers on-board the Planck satellite to measure temperature and polarization anisotropies in the Cosmic Microwave Background (CMB) in three frequency bands (30, 44 and 70 GHz). To calibrate and verify the performances of the LFI, a software suite named LIFE has been developed. Its aims are to provide a common platform to use for analyzing the results of the tests performed on the single components of the instrument (RCAs, Radiometric Chain Assemblies) and on the integrated Radiometric Array Assembly (RAA). Moreover, its analysis tools are designed to be used during the flight as well to produce periodic reports on the status of the instrument. The LIFE suite has been developed using a multi-layered, cross-platform approach. It implements a number of analysis modules written in RSI IDL, each accessing the data through a portable and heavily optimized library of functions written in C and C++. One of the most important features of LIFE is its ability to run the same data analysis codes both using ground test data and real flight data as input. The LIFE software suite has been successfully used during the RCA/RAA tests and the Planck Integrated System Tests. Moreover, the software has also passed the verification for its in-flight use during the System Operations Verification Tests, held in October 2008.
15947685
Parallel Astronomical Data Processing with Python: Recipes for multicore machines
Abstract High performance computing has been used in various fields of astrophysical research. But most of it is implemented on massively parallel systems (supercomputers) or graphical processing unit clusters. With the advent of multicore processors in the last decade, many serial software codes have been re-implemented in parallel mode to utilize the full potential of these processors. In this paper, we propose parallel processing recipes for multicore machines for astronomical data processing. The target audience is astronomers who use Python as their preferred scripting language and who may be using PyRAF/IRAF for data processing. Three problems of varied complexity were benchmarked on three different types of multicore processors to demonstrate the benefits, in terms of execution time, of parallelizing data processing tasks. The native multiprocessing module available in Python makes it a relatively trivial task to implement the parallel code. We have also compared the three multiprocessing approaches—Pool/Map, Process/Queue and Parallel Python. Our test codes are freely available and can be downloaded from our website.
116935590
The Planck Telescope
In this paper we present an overview of the Telescope designed for ESA’s mission dedicated to map the Cosmic Microwave Background Anisotropies and Polarization. Two instrument, LFI and HFI, operate in an overall frequency range between 25 and 900 GHz and share the focal region of the 1.5 meter optimized aplanatic telescope. The optimization techniques adopted for the optical design and the telescope characteristic are reported and discussed.
15013491
A SEARCH FOR THE OPTICAL COUNTERPART OF PSR B1951+32 IN THE SUPERNOVA REMNANT CTB 80
Using time-resolved two-dimensional aperture pho- tometry we have put upper limits on the pulsed emission from two proposed optical counterparts for PSR B1951+32. Our pulsed upper limits of mv;pulsed > 23:3, mb;pulsed > 24:4, for the first candidate and mv;pulsed > 23:6, mb;pulsed > 24:3 for the second, make it unlikely that either of these is, in fact, the pulsar. We discuss three further candidates, but also reject these on the basis of timing results. A search of a 5: 5 5: 00 5 area centred close to these stars failed to find any significant pulsations at the reported pulsar period.
119193844
Proper Motions in Globular Clusters using Deconvolution of HST Images
A sub-sampled deconvolution technique for crowded field photometry with the HST WFPC2 instrument was proposed by Butler (2000) and applied to search for optical counterparts to pulsars in globular clusters (Golden et al. 2001). Simulations showed that the method, which takes account of the point-spread function (PSF) spatial variation, can provide better star detection and recovers the resolution lost to aberrations and poor sampling. The original emphasis was on precision photometry in crowded fields. In the present work, we have extended this technique to determine proper motions of stars in globular clusters. Actual HST images of the globular clusters, along with realistic simulations of the globular clusters, were used to benchmark the technique for astrometric accuracy. The ultimate aim is to use this dynamical data to search for intermediate-mass black holes in globular cluster cores.