K2/TESS and HERMES reveal new details about four bright field stars

Star system: HD 73135 | Distance from the Sun: 668 light years

Researchers combined space-based K2 and TESS photometry with high-resolution HERMES spectroscopy to study four bright stars: HD 73135, BD +19° 2045, BD +19° 2046, and TYC 1395-855-1. Their analysis clarified the stars’ variability, chemical properties, and evolutionary status. HD 73135 shows a persistent modulation near 1.5 days, likely due to rotation, but an ellipsoidal-binary scenario is also possible. BD +19° 2045 is identified as a new candidate γ Doradus g-mode pulsator, while BD +19° 2046 and TYC 1395-855-1 are mostly non-variable in K2 but show low-frequency modulation in TESS data.

Spectroscopic analysis found that HD 73135 is chemically peculiar, displaying an Am star abundance pattern, while the other three stars are chemically normal. The study demonstrates the value of combining legacy ground-based data with modern photometric and spectroscopic observations to better understand stellar variability and evolution.

Key findings
- HD 73135 shows rotational or binary-induced variability and is chemically peculiar (Am star).
- BD +19° 2045 is a new γ Doradus candidate.
- BD +19° 2046 and TYC 1395-855-1 show low-frequency variability in TESS but not K2.
- Combining legacy and modern data improves stellar characterization.

Scientific study

High-precision K2/TESS Photometry and HERMES Spectroscopy of Four Bright Field Stars (external link)