Bibliographic Details
| Title: |
Wolf 327b: A new member of the pack of ultra-short-period super-Earths around M dwarfs |
| Authors: |
Murgas, F., Pallé, E., Orell-Miquel, J., Carleo, I., Peña-Moñino, L., Pérez-Torres, M., Watkins, C. N., Jeffers, S. V., Azzaro, M., Barkaoui, K., Belinski, A. A., Caballero, J. A., Charbonneau, D., Cheryasov, D. V., Ciardi, D. R., Collins, K. A., Cortés-Contreras, M., de Leon, J., Duque-Arribas, C., Enoc, G., Esparza-Borges, E., Fukui, A., Geraldía-González, S., Gilbert, E. A., Hatzes, A. P., Hayashi, Y., Henning, Th., Herrero, E., Jenkins, J. M., Lillo-Box, J., Lodieu, N., Lund, M. B., Luque, R., Montes, D., Nagel, E., Narita, N., Parviainen, H., Polanski, A. S., Reffert, S., Schlecker, M., Schöfer, P., Schwarz, R. P., Schweitzer, A., Seager, S., Stassun, K. G., Tabernero, H. M., Terada, Y., Twicken, J. D., Vanaverbeke, S., Winn, J. N., Zambelli, R., Amado, P. J., Quirrenbach, A., Reiners, A., Ribas, I. |
| Publication Year: |
2024 |
| Collection: |
Astrophysics |
| Subject Terms: |
Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics |
| More Details: |
Planets with orbital periods shorter than 1 day are rare and have formation histories that are not completely understood. Small ($R_\mathrm{p} < 2\; R_\oplus$) ultra-short-period (USP) planets are highly irradiated, probably have rocky compositions with high bulk densities, and are often found in multi-planet systems. Additionally, USP planets found around small stars are excellent candidates for characterization using present-day instrumentation. Of the current full sample of approximately 5500 confirmed exoplanets, only 130 are USP planets and around 40 have mass and radius measurements. Wolf 327 (TOI-5747) is an M dwarf ($R_\star = 0.406 \pm 0.015 \; R_\odot$, $M_\star = 0.405 \pm 0.019 \; M_\odot$, $T_{\mathrm{eff}}=3542 \pm 70$ K, and $V = 13$ mag) located at a distance $d = 28.5$ pc. NASA's planet hunter satellite, TESS, detected transits in this star with a period of 0.573 d (13.7 h) and with a transit depth of 818 ppm. Ground-based follow-up photometry, high resolution imaging, and radial velocity (RV) measurements taken with the CARMENES spectrograph confirm the presence of this new USP planet. Wolf 327b is a super-Earth with a radius of $R_\mathrm{p} = 1.24 \pm 0.06 \; R_\oplus$ and a mass of $M_\mathrm{p} = 2.53 \pm 0.46 \; M_\oplus$, yielding a bulk density of $7.24 \pm 1.66 $\,g cm$^{-3}$ and thus suggesting a rocky composition. Owing to its close proximity to its host star ($a = 0.01$ au), Wolf 327b has an equilibrium temperature of $996 \pm 22$ K. This planet has a mass and radius similar to K2-229b, a planet with an inferred Mercury-like internal composition. Planet interior models suggest that Wolf 327b has a large iron core, a small rocky mantle, and a negligible (if any) H/He atmosphere.
Comment: 26 pages, 19 figures. Accepted for publication in A&A |
| Document Type: |
Working Paper |
| Access URL: |
http://arxiv.org/abs/2401.12150 |
| Accession Number: |
edsarx.2401.12150 |
| Database: |
arXiv |
