Near IR observations of η Car: Reaching its critical rotation?

[摘要] We report a preliminary result in the monitoring of η Carinae in JHKs bands through the "spectroscopic" event of 2014.5 at InfraRed Survey Facility (IRSF) located in South African Astronomical Observatory (SAAO). The latest photometric data, combined with the data taken with the MK-II photometer [1], show a sign of the same cyclic variation in the J-H vs. H-K diagram reported by Mehner et al.[2]. The change can still be attributed to an apparent increase in black-body temperature, potentially reaching 3,000 to 6,000K as of March 2015.

[发布机构] Graduate School of Science, Nagoya University, Japan^1;ESO European Organisation for Astronomical Research in the Southern Hemisphere, Chile^2;Department of Physics and Astronomy, Graduate School of Science and Engineering, Kagoshima University, Japan^3

[效力级别] 天文学 [学科分类] 天文学(综合)

[关键词] Black body;Cyclic variations;Eta Carinae;Near-IR;Photometric data;South african astronomical observatories