ﻻ يوجد ملخص باللغة العربية
Using offset-corrected Gaia-EDR3 parallax measurements and spectrophotometric methods, we have determined distances for 69 massive stars in the Carina OB1 association and associated clusters: Trumpler 16 (21 stars), Trumpler 14 (20 stars), Trumpler 15 (3 stars), Bochum 11 (5 stars), and South Pillars region (20 stars). Past distance estimates to the Carina Nebula range from 2.2 to 3.6 kpc, with uncertainties arising from photometry and anomalous dust extinction. The EDR3 parallax solutions show considerable improvement over DR2, with typical errors $sigma_{varpi}/varpi approx$~3-5%. The O-type stars in the Great Carina Nebula lie at essentially the same distance ($2.35pm0.08$ kpc), quoting mean and rms variance. The clusters have distances of $2.32pm0.12$ kpc (Tr 16), $2.37pm0.15$ kpc (Tr 14), $2.36pm0.09$ kpc (Tr 15), and $2.33pm0.12$ kpc (Bochum 11) in good agreement with the $eta$ Car distance of around 2.3 kpc. O-star proper motions suggest internal (2D) velocity dispersions $sim4$ km/s for Tr 14 and Tr 16. Reliable distances allow estimates of cluster sizes, stellar dynamics, luminosities, and fluxes of photoionizing radiation incident on photodissociation regions in the region. We estimate that Tr 14 and Tr 16 have half-mass radii $r_h = 1.5-1.8$ pc, stellar crossing times $t_{rm cr} = r_h/v_m approx 0.7-0.8$ Myr, and two-body relaxation times $t_{rh} approx 40-80$ Myr. The underlying velocity dispersion for Tr 14, if a bound cluster, would be $v_m approx 2.1^{+0.7}_{-0.4}$ km/s for $N = 7600^{+5800}_{-2600}$ stars. With the higher dispersions of the O-stars, mass segregation might occur slowly, on times scales of 3-6~Myr.
We present the first extensive spectroscopic study of the global population in star clusters Trumpler~16, Trumpler~14 and Collinder~232 in the Carina Nebula, using data from the Gaia-ESO Survey, down to solar-mass stars. In addition to the standard h
In this paper we present and analyze new CCD $UBVRI$ photometry down to $V approx$ 21 in the region of the young open cluster Collinder 232, located in the Carina spiral arm, and discuss its relationship to Trumpler 14 and Trumpler 16, the two most p
We investigate the physical conditions of the CO gas near the young star cluster, Trumpler 14 of the Carina Nebula. The observations presented in this work are taken with the Fourier Transform Spectrometer (FTS) of the Spectral and Photometric Imagin
The second data release of it Gaia rm revealed a parallax zero point offset of $-0.029$~mas based on quasars. The value depended on the position on the sky, and also likely on magnitude and colour. The offset and its dependence on other parameters in
We analyze the 3D morphology and kinematics of 13 open clusters (OCs) located within 500 pc of the Sun, using Gaia EDR3 and kinematic data from literature. Members of OCs are identified using the unsupervised machine learning method StarGO, using 5D