POSYDON-code / POSYDON-code/POSYDON

Eccentricity is negative for some binaries

Open
#486 0 comments 0 reactions 1 assignee View on GitHub

@maxbriel is already working on this.

Since Apr 8, 2025.

bug
Dominant language
Python
Stars
45
Forks
37
Avg merge
8d 20h
Merged PRs (30d)
5

Description

The binary eccentricity is negative in some cases, which is causing these systems to fail in step_SN (the check for negative eccentricity is in the inspiral_timescale_from_separation function in common_functions):

Traceback (most recent call last):
  File "/home/cel2717/.conda/envs/posydon-source/lib/python3.11/site-packages/posydon/popsyn/binarypopulation.py", line 328, in _safe_evolve
    binary.evolve()
  File "/home/cel2717/.conda/envs/posydon-source/lib/python3.11/site-packages/posydon/binary_evol/binarystar.py", line 222, in evolve
    self.run_step()
  File "/home/cel2717/.conda/envs/posydon-source/lib/python3.11/site-packages/posydon/binary_evol/binarystar.py", line 249, in run_step
    next_step(self)
  File "/home/cel2717/.conda/envs/posydon-source/lib/python3.11/site-packages/posydon/binary_evol/SN/step_SN.py", line 442, in __call__
    binary.inspiral_time = inspiral_timescale_from_separation(
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/cel2717/.conda/envs/posydon-source/lib/python3.11/site-packages/posydon/utils/common_functions.py", line 851, in inspiral_timescale_from_separation
    raise ValueError("Eccentricity is < 0, which is not a physical value.")
ValueError: Eccentricity is < 0, which is not a physical value.

Failed Binary Initial Conditions:
S1 mass: 6.322647708094897
S2 mass: 6.243419995426043
S1 state: H-rich_Core_H_burning
S2 state: H-rich_Core_H_burning
orbital period: 313.8916137815911
eccentricity: 0.0
binary state: detached
binary event: detached
S1 natal kick array: [None None None None]
S2 natal kick array: [None None None None]

Contributor guide

No contributing guide indexed for this repository

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Assessment

This issue has not been assessed yet.

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.