Abstract

The Laser Interferometer Gravitational Wave Observatory (LIGO) is making great strides towards performing scientifically significant data analysis using Grid resources. As part of the collaboration between the LIGO and the GriPhyN projects, we have focused on a specific LIGO problem: the pulsar search (shown below). The data needed to conduct the search is a long stretch (~ 4 months, 2x1011 points) of a single channel—the gravitational wave strain channel. The power spectra of the small segments are stacked to make a large frequency-time image, perhaps 4x105 on each side. The pulsar search consists of searching for coherent signals in this image. A source would appear on the frequencytime image as a wavering line, whose frequency might be 1 kHz, but modulated by a few parts in 106 over periods of 1 day and a few parts in 104 over periods of 1 year. In addition, if the source exhibits any secular variations due to slowing down of its rotational period, these will be encoded in the data, as well.
The pulsar search is very compute and data intensive and requires more resources than those available in the LIGO Scientific Collaboration. In order to take advantage of the Grid resources, we had to integrate LIGO’s existing data analysis into the Grid environment. The LIGO Data Analysis System (LDAS) can perform a wide range of sophisticated and computationally intensive data analysis. We have developed an infrastructure in which LDAS can be accessed as a Grid resource, and in which LDAS can schedule its jobs on the Grid. To achieve integration of LDAS into the Grid environment, we have designed and implemented Globus interfaces …

Date

September 24, 2025

Authors

Amit Agarwal Shishir Bharati, James Blythe, Ewa Deelman, Yolanda Gil, Carl Kesselman, Gaurang Mehta, Sonal Patil, Srividya Rao, Gurmeet Singh, Marcus Thiebaux, Karan Vahi, Stuart Anderson, Maria Alessandra Papa, Alicia M Sintes