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arXiv · 2410.08943

BD+44 493: Chemo-Dynamical Analysis and Constraints on Companion Planetary Masses from WIYN/NEID Spectroscopy

Vinicius M. Placco·Arvind F. Gupta·Felipe Almeida-Fernandes·Sarah E. Logsdon·Jayadev Rajagopal·Erika M. Holmbeck·Ian U. Roederer·John Della Costa·Pipa Fernandez·Eli Golub·Jesus Higuera·Yatrik Patel·Susan Ridgway·Heidi Schweiker
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Abstract

In this work, we present high-resolution (R~100,000), high signal-to-noise (S/N~800) spectroscopic observations for the well-known, bright, extremely metal-poor, carbon-enhanced star BD+44 493. We determined chemical abundances and upper limits for 17 elements from WIYN/NEID data, complemented with 11 abundances re-determined from Subaru and Hubble data, using the new, more accurate, stellar atmospheric parameters calculated in this work. Our analysis suggests that BD+44 493 is a low-mass (0.83Msun) old (12.1-13.2Gyr) second-generation star likely formed from a gas cloud enriched by a single metal-free 20.5Msun Population III star in the early Universe. With a disk-like orbit, BD+44 493 does not appear to be associated with any major merger event in the early history of the Milky Way. From the precision radial-velocity NEID measurements (median absolute deviation - MAD=16m/s), we were able to constrain companion planetary masses around BD+44 493 and rule out the presence of planets as small as msin(i)=2MJ out to periods of 100 days. This study opens a new avenue of exploration for the intersection between stellar archaeology and exoplanet science using NEID.

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Vinicius M. Placco, Arvind F. Gupta, Felipe Almeida-Fernandes, Sarah E. Logsdon, Jayadev Rajagopal, Erika M. Holmbeck, Ian U. Roederer, John Della Costa, Pipa Fernandez, Eli Golub, Jesus Higuera, Yatrik Patel, Susan Ridgway, Heidi Schweiker. 2024-10-11. BD+44 493: Chemo-Dynamical Analysis and Constraints on Companion Planetary Masses from WIYN/NEID Spectroscopy. https://arxiv.org/abs/2410.08943

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