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The S tack S lide Search. Gregory Mendell and Mike Landry LIGO Hanford Observatory. http://www.ligo-wa.caltech.edu. Summary: November 2003 LSC Meeting. The StackSlide Search.
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The StackSlide Search Gregory Mendell and Mike Landry LIGO Hanford Observatory http://www.ligo-wa.caltech.edu Summary: November 2003 LSC Meeting LIGO-G030575-00-W
The StackSlide Search • An incoherent search method that stacks and slides power to search for periodic sources. (P. Brady & T. Creighton Phys. Rev. D61 (2000) 082001; gr-qc/9812014.) • The periodic search is computationally bound. A hierarchical approach that combines coherent & incoherent methods is needed to optimize sensitivity. • Sources like LXMBs with short coherence times (~ 2 weeks) require incoherent methods. • Want to add StackSlide to the incoherent toolbag along with Hough transforms. • Mike Landry and I proposed that we write a stackslide DSO in June 2003. LIGO-G030575-00-W
StackSlide ABCs Bins with frequency domain data, e.g., from SFTs. PSDs or F-statistic from SFTs B.Make Stacks C.Slide and output Sum A. Input Blocks of data (from coherent methods) (incoherent step) LIGO-G030575-00-W
Progress to Date We have working code that stack & slides PSDs from SFTs on a flat parameter space! Implemented SLIDING since last LSC LIGO-G030575-00-W
StackSlide Basic Statistics One stack: (N samples) (Ave M stacks) Detection if: For A2N > 2 For A2N < 2 M = number of SFTs. If F-statistic P(x) = Cx2M-1e-Mx for mean F = 2. PDF for gaussian noise, normalized to mean of 1. LIGO-G030575-00-W
Study of E10 Injected Pulsar 0. LIGO-G030575-00-W
Study of E10 Injected Pulsar 2. LIGO-G030575-00-W
Study of E10 Injected Pulsar 3. LIGO-G030575-00-W
Study of E10 Injected Pulsar 4. LIGO-G030575-00-W
Big “to do” list still exists… • Next major effort is to debug on simple test data and S2/E10/S3 injections. • Need to add code that handles thresholds, parameter space metric, stacks F-statistic, runs in parallel, etc…. • Need to decide on windowing/overlapping/oversampling of SFTs etc… • SET UP PIPELINE THAT LEAD TO DETECTION OR UPPER LIMIT! Goal: • Set preliminary upper limit on S2/S3 data on same parameter space as Hough code. LIGO-G030575-00-W