Hostname: page-component-76fb5796d-45l2p Total loading time: 0 Render date: 2024-04-29T15:51:01.027Z Has data issue: false hasContentIssue false

Empirical constraints for the instability strip from the analysis of LMC Cepheids

Published online by Cambridge University Press:  06 February 2024

F. Espinoza-Arancibia*
Affiliation:
Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences, Bartycka 18, 00-716 Warsaw, Poland
B. Pilecki
Affiliation:
Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences, Bartycka 18, 00-716 Warsaw, Poland

Abstract

The instability strip (IS) of classical Cepheids has been extensively studied theoretically. Comparison of the theoretical IS edges with those obtained empirically, using the most recent Cepheids catalogs available, can provide us with insights into the physical processes that determine the position of the IS boundaries. We investigate the empirical positions of the IS of the classical Cepheids in the Large Magellanic Cloud (LMC) using data of classical fundamental-mode and first-overtone LMC Cepheids from the OGLE-IV variable star catalog, together with a recent high-resolution reddening map from the literature. We studied their position on the Hertzsprung-Russell diagram and determined the IS borders by tracing the edges of the color distribution along the strip. We obtain the blue and red edges of the IS in V- and I-photometric bands, in addition to Teff and log L. The results obtained show a break located at the Cepheids’ period of about 3 days, which was not reported before. This phenomenon is most likely explained by the depopulation of second and third crossing classical Cepheids in the faint part of the IS, since blue loops of evolutionary tracks in this mass range do not extend blueward enough to cross the IS at the LMC metallicity. Furthermore, our empirical borders show good agreement with theoretical ones published in the literature. This proves that our empirical IS is a useful tool to put constraints on theoretical models.

Type
Contributed Paper
Copyright
© The Author(s), 2024. Published by Cambridge University Press on behalf of International Astronomical Union

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Anderson, R. I., Saio, H., Ekström, S., Georgy, C., & Meynet, G. 2016, A&A, 591, A8 Google Scholar
Bauer, F., Afonso, C., Albert, J. N., et al. 1999, A&A, 348, 175 Google Scholar
Bhardwaj, A., Kanbur, S. M., Macri, L. M., et al. 2016, MNRAS, 457, 1644 Google Scholar
Bono, G., Caputo, F., Cassisi, S., et al. 2000 a, ApJ, 543, 955Google Scholar
Bono, G., Castellani, V., & Marconi, M. 2000 b, ApJ, 529, 293Google Scholar
Caldwell, J. A. R. & Laney, C. D. 1991, in The Magellanic Clouds, ed. R. Haynes & D. Milne, Vol. 148, 249 CrossRefGoogle Scholar
Chen, B. Q., Guo, H. L., Gao, J., et al. 2022, MNRAS, 511, 1317 Google Scholar
De Somma, G., Marconi, M., Molinaro, R., et al. 2022, ApJs, 262, 25 Google Scholar
Eggenberger, P., Meynet, G., Maeder, A., et al. 2008, Ap&SS, 316, 43 Google Scholar
Fernie, J. D. 1990, ApJ, 354, 295 Google Scholar
Fiorentino, G., Caputo, F., Marconi, M., & Musella, I. 2002, ApJ, 576, 402 Google Scholar
Fiorentino, G., Marconi, M., Musella, I., & Caputo, F. 2007, A&A, 476, 863 Google Scholar
Górski, M., Zgirski, B., Pietrzyński, G., et al. 2020, ApJ, 889, 179 Google Scholar
Hidalgo, S. L., Pietrinferni, A., Cassisi, S., et al. 2018, ApJ, 856, 125 Google Scholar
Inno, L., Bono, G., Matsunaga, N., et al. 2016, ApJ, 832, 176 Google Scholar
Jacyszyn-Dobrzeniecka, A. M., Skowron, D. M., Mróz, P., et al. 2016, Acta Astron., 66, 149 Google Scholar
Madore, B. F., Freedman, W. L., & Moak, S. 2017, ApJ, 842, 42 Google Scholar
Martin, W. L., Warren, P. R., & Feast, M. W. 1979, MNRAS, 188, 139 CrossRefGoogle Scholar
Musella, I. 2022, Universe, 8, 335 Google Scholar
Narloch, W., Pietrzyński, G., Kołaczkowski, Z., et al. 2019, MNRAS, 489, 3285Google Scholar
Paxton, B., Bildsten, L., Dotter, A., et al. 2011, ApJs, 192, 3 CrossRefGoogle Scholar
Paxton, B., Smolec, R., Schwab, J., et al. 2019, ApJs, 243, 10 Google Scholar
Pel, J. W. & Lub, J. 1978, in The HR Diagram - The 100th Anniversary of Henry Norris Russell, ed. Philip, A. G. D. & Hayes, D. S., Vol. 80, 229Google Scholar
Petroni, S., Bono, G., Marconi, M., & Stellingwerf, R. F. 2003, ApJ, 599, 522 Google Scholar
Pietrzyński, G., Graczyk, D., Gallenne, A., et al. 2019, Nature, 567, 200 Google Scholar
Pilecki, B. 2022, in XL Polish Astronomical Society Meeting, ed. E. Szuszkiewicz, A. Majczyna, K. Małek, M. Ratajczak, E. Niemczura, U. B"kak-St"keślicka, R. Poleski, M. Bilicki, & Ł. Wyrzykowski, Vol. 12, 174–177Google Scholar
Pilecki, B., Pietrzyński, G., Anderson, R. I., et al. 2021, ApJ, 910, 118 Google Scholar
Pilecki, B., Thompson, I. B., Espinoza-Arancibia, F., et al. 2022, ApJl, 940, L48 Google Scholar
Ripepi, V., Chemin, L., Molinaro, R., et al. 2022, MNRAS, 512, 563 Google Scholar
Sandage, A., Tammann, G. A., & Reindl, B. 2004, A&A, 424, 43 Google Scholar
Sandage, A., Tammann, G. A., & Reindl, B. 2009, A&A, 493, 471 Google Scholar
Sharpee, B., Stark, M., Pritzl, B., et al. 2002, AJ, 123, 3216 Google Scholar
Skowron, D. M., Skowron, J., Udalski, A., et al. 2021, ApJs, 252, 23 Google Scholar
Smolec, R. & Moskalik, P. 2008, Acta Astron., 58, 193 Google Scholar
Soszyński, I., Udalski, A., Szymański, M. K., et al. 2015, Acta Astron., 65, 297 Google Scholar
Tammann, G. A., Sandage, A., & Reindl, B. 2003, A&A, 404, 423 Google Scholar
Turner, D. G. 2001, Odessa Astronomical Publications, 14, 166 Google Scholar
Ulaczyk, K., Szymański, M. K., Udalski, A., et al. 2013, Acta Astron., 63, 159 Google Scholar
Walmswell, J. J., Tout, C. A., & Eldridge, J. J. 2015, MNRAS, 447, 2951 Google Scholar
Worthey, G. & chul Lee, H. 2011, The Astrophysical Journal Supplement Series, 193, 1Google Scholar
Xu, H. Y. & Li, Y. 2004 a, A&A, 418, 213Google Scholar
Xu, H. Y. & Li, Y. 2004 b, A&A, 418, 225Google Scholar