Stochastic Gravitational Wave Background: Sources and Searches
A cura di
Anibar Ain(IUCAA)
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Europe/Rome
Aula Conversi (Dipartimento di Fisica - Ed. G. Marconi)
Aula Conversi
Dipartimento di Fisica - Ed. G. Marconi
Descrizione
Gravitational Waves are propagating distortions of spacetime predicted in Einstein’s general theory of relativity. Various types of sources are expected to emit GWs of different frequencies and durations, which may contain important astrophysical information not accessible to traditional electro-magnetic astronomy. A stochastic GW background (SGWB) is one such source created by a large number of unresolved astrophysical sources and phenomena in the early universe like cosmic inflation. We estimated the SGWB generated by all the planets in our galaxy along with the entire universe and studied it! s detectability. At higher frequencies, in the band of ground-based interferometric detectors, probing an anisotropic SGWB is best achieved by employing the GW radiometer algorithm. It maps the GW sky using cross-correlation of data from pairs of detectors. Exploiting a temporal symmetry in the radiometer algorithm we have developed and implemented a technique to fold cross-spectral data for the whole observation period to only one sidereal day without any loss of precision. Folding thus makes data analysis more than two orders faster, making it possible to perform searches which have been computationally prohibitive. Being only about a gigabyte in size, folded data offers enormous portability and convenience in handling. Folding incorporates most of the details involved in preprocessing, alleviating many dirty steps otherwise involved in the main analysis.
