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A surrogate model for gravitational waveforms of spin-aligned binary black holes with eccentricities

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 نشر من قبل Wen-Biao Han
 تاريخ النشر 2021
  مجال البحث فيزياء
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A waveform model for the eccentric binary black holes named SEOBNRE has been used to analyze the LIGO-Virgos gravitational wave data by several groups. The accuracy of this model has been validated by comparing it with numerical relativity. However, SEOBNRE is a time-domain model, and the efficiency for generating waveforms is a bottleneck in data analysis. To overcome this disadvantage, we offer a reduced-order surrogate model for eccentric binary black holes based on the SEOBNRE waveforms. This surrogate model (SEOBNRE_S) can simulate the complete inspiral-merger-ringdown waves with enough accuracy, covering eccentricities from 0 to 0.25 (0.1), and mass ratio from 1:1 to 5:1 (2:1) for nonspinning (spinning) binaries. The speed of waveform generation is accelerated about $10^2 sim 10^3$ times than the original SEOBNRE model. Therefore SEOBNRE_S could be helpful in the analysis of LIGO data to find potential eccentricities.

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