Absolute parameters of young stars: QZ Carinae
| dc.contributor.author | Walker, W. S. G. | |
| dc.contributor.author | Blackford, M. | |
| dc.contributor.author | Butland, R. | |
| dc.contributor.author | Budding, E. | |
| dc.date.accessioned | 2025-01-27T20:27:03Z | |
| dc.date.available | 2025-01-27T20:27:03Z | |
| dc.date.issued | 2017 | |
| dc.department | Çanakkale Onsekiz Mart Üniversitesi | |
| dc.description.abstract | New high-resolution spectroscopy and BVR photometry together with literature data on the complex massive quaternary star QZ Car are collected and analysed. Absolute parameters are found as follows. System A: M-1 = 43 (+/- 3), M-2 = 19 (+3 -7), R-1 = 28 (+/- 2), R-2 = 6 (+/- 2), (circle dot); T-1 similar to 28 000, T-2 similar to 33 000 K; System B: M-1 = 30 (+/- 3), M-2 = 20 (+/- 3), R-1 = 10 (+/- 0.5), R-2 = 20 (+/- 1), (circle dot); T-1 similar to 36 000, T-2 similar to 30 000 K (model dependent temperatures). The wide system AB: Period = 49.5 (+/- 1) yr, Epochs, conjunction = 1984.8 (+/- 1), periastron = 2005.3 (+/- 3) yr, mean separation = 65 (+/- 3), (au); orbital inclination = 85 (+5 - 15) deg, photometric distance similar to 2700 (+/- 300) pc, age = 4 (+/- 1) Myr. Other new contributions concern: (a) analysis of the timing of minima differences (O - C) s for the eclipsing binary (System B); (b) the width of the eclipses, pointing to relatively large effects of radiation pressure; (c) inferences from the rotational widths of lines for both Systems A and B; and (d) implications for theoretical models of early-type stars. While feeling greater confidence on the quaternary's general parametrization, observational complications arising from strong wind interactions or other, unclear, causes still inhibit precision and call for continued multiwavelength observations. Our high-inclination value for the AB system helps to explain failures to resolve the wide binary in the previous years. The derived young age independently confirms membership of QZ Car to the open cluster Collinder 228. | |
| dc.description.sponsorship | Southern Binaries Programme | |
| dc.description.sponsorship | Generous allocations of time on the 1m McLennnan Telescope and HERCULES spectrograph at the Mt John University Observatory in support of the Southern Binaries Programme have been made available through its TAC and supported by its Director, Dr K. Pollard and previous Director, Prof. J. B. Hearnshaw. Useful help at the telescope were provided by the MJUO management (N. Frost and previously A. Gilmore and P. Kilmartin). Assistance with the use and development of the HRSP software has been given by its author Dr J. Skuljan. Encouragement and support for this programme has been shown by the School of Chemical and Physical Sciences of the Victoria University of Wellington, as well as the Royal Astronomical Society of New Zealand and its Variable Stars South section (http://www.variablestarssouth.org). We thank VSS's former-director Tom Richards for advocating DSLR photometry in support of the Southern Binaries Programme, also the AAVSOnet Telescope Allocation Committee for telescope time in 2014 and 2015. We appreciate the hard work and dedication of AAVSOnet site managers Peter Nelson (BSM South) and Greg Bolt (BSM Berry). Dr P. Mayer kindly sent additional photometric details on QZ Car that were used in the construction of the O - C curve. As well, Dr H. Drechsel made very useful comments regarding the effects of radiation pressure on the surficial distortions of very hot close binaries. The astrophysics group at COMU have been supportive of this research. | |
| dc.identifier.doi | 10.1093/mnras/stx1153 | |
| dc.identifier.endpage | 2017 | |
| dc.identifier.issn | 0035-8711 | |
| dc.identifier.issn | 1365-2966 | |
| dc.identifier.issue | 2 | |
| dc.identifier.startpage | 2007 | |
| dc.identifier.uri | https://doi.org/10.1093/mnras/stx1153 | |
| dc.identifier.uri | https://hdl.handle.net/20.500.12428/22560 | |
| dc.identifier.volume | 470 | |
| dc.identifier.wos | WOS:000406839900055 | |
| dc.identifier.wosquality | Q1 | |
| dc.indekslendigikaynak | Web of Science | |
| dc.language.iso | en | |
| dc.publisher | Oxford Univ Press | |
| dc.relation.ispartof | Monthly Notices of The Royal Astronomical Society | |
| dc.relation.publicationcategory | info:eu-repo/semantics/openAccess | |
| dc.rights | info:eu-repo/semantics/closedAccess | |
| dc.snmz | KA_WoS_20250125 | |
| dc.subject | binaries: close | |
| dc.subject | stars: early-type | |
| dc.subject | stars: individual: QZ Car | |
| dc.subject | Galaxy: stellar content | |
| dc.title | Absolute parameters of young stars: QZ Carinae | |
| dc.type | Article |
