OGLE Study of the Sagittarius Dwarf Spheroidal Galaxy and its M54 Globular Cluster

• Autorzy: Hamanowicz A. , Pietrukowicz P. , Udalski A. , Mróz P. , Soszyński I. , Szymański M. K. , Skowron J. , Poleski R. , Wyrzykowski Ł. , Kozłowski S. , Pawlak M. , Ulaczyk K.
• Języki publikacji: EN

Abstrakty

EN

We use the fundamental-mode RR Lyr-type variable stars (RRab) from OGLE-IV survey to draw a 3D picture of the central part of the tidally disrupted Sagittarius Dwarf Spheroidal (Sgr dSph) galaxy. We estimate the line-of-sight thickness of the Sgr dSph stream to be FWHM_cen=2.42 kpc. Based on OGLE-IV observations collected in seasons 2011-2014 we conduct a comprehensive study of stellar variability in the field of the globular cluster M54 (NGC 6715) residing in the core of this dwarf galaxy. Among the total number of 268 detected variable stars we report the identification of 174 RR Lyr stars, four Type II Cepheids, 51 semi-regular variable red giants, three SX Phe-type stars, 18 eclipsing binary systems. Eighty-three variable stars are new discoveries. The distance to the cluster determined from RRab stars is d_M54=26.7±0.03_stat±1.3_sys kpc. From the location of RRab stars in the period-amplitude (Bailey) diagram we confirm the presence of two old populations, both in the cluster and the Sgr dSph stream.

Słowa kluczowe

EN

galaxies: individual: Sgr dSph; globular clusters: individual: M54 (NGC 6715); stars: variables: RR Lyr; Cepheids

• Wydawca: Copernicus Foundation for Polish Astronomy
• Czasopismo: Acta Astronomica
• Rocznik: 2016
• Tom: Vol. 66, No. 2
• Strony: 197--217
• Opis fizyczny: Bibliogr. 48 poz., rys., wykr.

Twórcy

autor

Hamanowicz A.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland

autor

Pietrukowicz P.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland

autor

Udalski A.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland

autor

Mróz P.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland

autor

Soszyński I.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland

autor

Szymański M. K.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland

autor

Skowron J.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland

autor

Poleski R.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland
• Department of Astronomy, Ohio State University, 140 W. 18th Ave., Columbus, OH 43210, USA

autor

Wyrzykowski Ł.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland

autor

Kozłowski S.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland

autor

Pawlak M.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland

autor

Ulaczyk K.

• Warsaw University Observatory, Al. Ujazdowskie 4, 00-478 Warszawa, Poland
• Department of Physics, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK

Bibliografia

• Alard, C. 2001, A&A, 377, 389.
• Alcock, C., et al. 1997, ApJ, 474, 217.
• Bellazzini, M., et al. 2008, AJ, 136, 1147.
• Belokurov, V., et al. 2006, ApJ, 642, L137.
• Belokurov, V., et al. 2014, MNRAS, 437, 116.
• Carretta, E., et al. 2010, A&A, 520A, 95.
• Catelan, M., Pritzl B.J., and Smith, H.A. 2004, ApJS, 154, 633.
• Chen, B., Figueras, F., Torra, J., Jordi, C., Luri, X., and Galadí-Enríquez, D. 1999, A&A, 352, 459.
• Clement, C.M., et al. 2001, AJ, 122, 2587.
• Cseresnjes, P., Alard, C., and Guibert, J. 2000, A&A, 357, 871.
• Cseresnjes, P. 2001, A&A, 375, 909.
• Dolphin, A.E. 2000a, PASP, 112, 1383.
• Dolphin, A.E. 2000b, PASP, 112, 1397.
• Figuera Jaimes, R., et al. 2016, A&A, in press, arXiv:1605.06141.
• Gonzalez, O.A., Rejkuba, M., Zoccali, M., Valenti, E., Minniti, D., Schultheis, M., Tobar, R., and Chen, B. 2012, A&A, 543A, 13.
• Harris, W.E. 1996, AJ, 112, 1487.
• Ibata, R.A., Gilmore, G., and Irwin, M.J. 1994, Nature, 370, 194.
• Jurcsik, J. 1995, Acta Astron., 45, 653.
• Jurcsik, J., and Kovács, G. 1996, A&A, 312, 111.
• Kunder, A., and Chaboyer, B. 2009, AJ, 137, 4478.
• Layden, A.C., and Sarajedini, A. 1997, ApJ, 486, L107.
• Layden, A.C., and Sarajedini, A. 2000, AJ, 119, 1760.
• Majewski, S.R., Skrutskie, M.F., Weinberg, M.D., and Ostheimer, J.C. 2003, ApJ, 599, 1082.
• Mateo, M., Udalski, A., Szymański, M., Kaluzny, J., Kubiak, M., and Krzemiński, W. 1995a, AJ, 109, 588.
• Mateo, M., Kubiak, M., Szymański, M., Kaluzny, J., Krzemiński, W., and Udalski, A. 1995b, AJ, 110, 1141.
• Montiel, E.J., and Mighell, K.J. 2010, AJ, 140, 1500.
• Monaco, L., Bellazzini, M., Ferraro, F.R., and Pancino, E. 2004, MNRAS, 353, 874.
• Monaco, L., Bellazzini, M., Ferraro, F.R., and Pancino, E. 2005, MNRAS, 356, 1396.
• Mróz, P., et al. 2015, Acta Astron., 65, 313.
• Nataf, D.M., et al. 2013, ApJ, 769, 88.
• Pietrukowicz, P. 2016, in: “The General Assembly of Galaxy Halos: Structure, Origin and Evolution”, IAUS Proceedings, 317, p. 116.
• Pietrukowicz, P., et al. 2013, Acta Astron., 811, 12.
• Pietrukowicz, P., et al. 2015, ApJ, 811, 113.
• Rosino, L. 1952, Memorie della Societá Astronomia Italiana, 23, 49.
• Rosino, L., and Nobili, F. 1958, Memorie della Societá Astronomia Italiana, 29, 413.
• Sarajedini, A., and Layden, A.C. 1995, AJ, 109, 1086.
• Schwarzenberg-Czerny, A. 1996, ApJ, 460, L107.
• Schechter, P.L., Mateo, M, and Saha, A. 1993, PASP, 105, 1342.
• Schlafly, E.F., and Finkbeiner, D.P. 2011, ApJ, 737, 103.
• Schlegel, D.J., Finkbeiner, D.P., and Davis, M. 1998, ApJ, 500, 525.
• Smolec, R. 2005, Acta Astron., 55, 59.
• Sollima, A., Cacciari, C., Bellazzini, M., and Colucci, S. 2010, MNRAS, 406, 329.
• Soszyński, I., et al. 2013, Acta Astron., 63, 21.
• Soszyński, I., et al. 2014, Acta Astron., 64, 177.
• Soszyński, I., et al. 2015, Acta Astron., 65, 297.
• Torrealba, G., et al. 2015, MNRAS, 446, 2251.
• Udalski, A., Szymański, M. K., and Szymański, G. 2015, Acta Astron., 65, 1.
• Zinn, R., Horowitz, B., Vivas, A. K., Baltay, C., Ellman, N., Hadjiyska, E., Rabinowitz, D., and Miller, L. 2014, ApJ, 781, 22.

Uwagi

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).