[Users] Residual eccentricity in BNS

[Lorenzo Cipriani]

Hi everyone,

I hope this message finds you well.

I am running an equal mass BNS simulation and I find that the Newtonian distance from the origin of the center of mass of one star has strong oscillations that seem to be due to a residual eccentricity in the initial data (computed with Lorene). A modulation is also present in the GW strain and doesn't seem to disappear changing the omega_0 parameter in the fixed frequency integration to compute h (I use Kuibit by the way).

I have a few questions:
      1) Does the eccentricity in the ID grow only if the two stars are closer or are there other relevant parameters?
      2) Given an initial eccentricity, do lower masses simply show the modulation more (since the modulus of the strain is smaller)?
      3) Looking online I have found references to a routine to reduce eccentricity for BBH simulations. Is there anything similar for BNS?

I know some residual eccentricity is to be expected, but this seems excessive. For reference I have uploaded the parameter file as well.

Thank you very much,
Lorenzo Cipriani
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