2025A&A...701A.242R

Query : 2025A&A...701A.242R

2025A&A...701A.242R - Astronomy and Astrophysics, volume 701A242 (2025/9-1)

The Corona-Australis star-forming region New insights on its formation history from detailed stellar and disk analysis.

RIGLIACO E., GRATTON R. and NASCIMBENI V.

Abstract (from CDS):

Context. The star-forming complex of Corona Australis (CrA) is one of the closest and most isolated molecular clouds. It belongs to a chain of clusters that show age gradients with distance from the galactic plane.
Aims. We aim to provide suggestions regarding its formation history by examining the stellar and disk populations, the stellar multiplicity, and the interstellar absorption.
Methods. We made a census of stars and disks using Gaia DR3 and infrared data. Interstellar absorption in the direction of each star was derived by comparing spectral types from the literature and Gaia colors. Stellar multiplicity analysis accounts for both direct observation of visual companions (Gaia data and high-contrast imaging) and indirect detection of the presence of companions (eclipsing binaries, spectroscopic binaries, and astrometry). The properties of the disks were obtained from the slopes of the spectral energy distributions.
Results. As found in previous studies, the CrA complex can be divided into two regions: a younger region (CrA-Main: 3±1 Myr) and an older one (CrA-North: 6.7±0.3 Myr), which are slightly younger than previously thought. Moreover, while CrA-Main still appears bound to the gas, CrA-North is unbound and expanding. The stars that belong to CrA-North were in the most compact configuration 3.72 Myr ago. At that time, CrA-Main and CrA-North were also much closer to each other than they appear now. The fraction of disk-bearing stars is higher in CrA-Main than in CrA-North, as also expected due to the younger age of CrA-Main.
Conclusions. We propose a formation history scenario for the CrA-complex. It started between 15 and 18 Myr ago with supernovae (SNe) explosions in the Upper Centaurus-Lupus complex, followed by a quiescent phase with little star formation. A star formation episode ∼7 Myr ago formed CrA-North stars. About 3.7 Myr ago, a second SN explosion south of CrA-North triggered star formation in CrA-Main. This last SN might have been the origin of the pulsar RX J1856.5-3754.

Abstract Copyright: © The Authors 2025

Journal keyword(s): stars: formation - stars: general - stars: kinematics and dynamics

VizieR on-line data: <Available at CDS (J/A+A/701/A242): tableb1.dat tableb2.dat>

Status at CDS : Tables of objects will be appraised for possible ingestion in SIMBAD.

Simbad objects: 32

goto Full paper

goto View the references in ADS

Number of rows : 32
N Identifier Otype ICRS (J2000)
RA 		ICRS (J2000)
DEC 		Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2026 		#notes
1 NAME THA MGr 00 00 -62.0           ~ 540 0
2 Cl Alessi 13 OpC 03 27 32.7 -35 50 45           ~ 92 0
3 NAME Taurus Cluster OpC 04 24 03.905 +26 53 24.40           ~ 79 0
4 NAME 32 Ori group OpC 05 27 11 +06 16.0           ~ 84 0
5 Cl Mamajek 1 OpC 08 42 32.9 -78 57 47           ~ 392 0
6 NAME Cha 1 MoC 11 06 48 -77 18.0           ~ 1266 1
7 NAME eps Cha Association OpC 11 59 51 -78 12.4           ~ 188 0
8 NAME Cha II MoC 12 54 -77.2           ~ 361 0
9 NAME Upper Centaurus Lupus MGr 15 24 -41.9           ~ 567 1
10 NAME Lupus Complex SFR 16 03 -38.1           ~ 851 0
11 NAME Upper Sco Association As* 16 12 -23.4           ~ 1586 1
12 NAME Upper Sco-Cen As* 16 15 -24.2           ~ 1497 1
13 NAME Ophiuchus Molecular Cloud SFR 16 28 06 -24 32.5           ~ 3969 1
14 2MASS J18351442-3443062 Y*O 18 35 14.4233501975 -34 43 06.227911640           M5 7 0
15 2MASS J18481012-3850421 Y*O 18 48 10.1383233462 -38 50 42.189783008           M8 6 0
16 2MASS J18481828-3711033 Y*O 18 48 18.2873262240 -37 11 03.395335128           M3.75 6 0
17 2MASS J18500856-3715337 Y*O 18 50 08.5636495224 -37 15 33.757984404           M4.75 8 0
18 NAME SDG G 18 55 19.0 -30 32 43   4.5 3.6     ~ 2438 2
19 RX J1856.6-3754 Psr 18 56 35.11 -37 54 30.5     25.7     ~ 456 0
20 NGC 6723 GlC 18 59 33.15 -36 37 56.1           ~ 543 0
21 HD 176269 Or* 19 01 03.2540527320 -37 03 39.303126756   6.54 6.69     B9V 74 0
22 HD 176270 Or* 19 01 04.3028373864 -37 03 41.666365152   6.37 6.40     B9V 64 0
23 GSC 07421-02198 Y*O 19 01 28.7317755864 -36 59 31.793030484         13.15 M1.0 20 0
24 2MASS J19013357-3700304 Or* 19 01 33.5761986624 -37 00 30.453110028           M6 51 0
25 V* TY CrA Ae* 19 01 40.8284458320 -36 52 33.816176040 10.03 9.92 9.39     B9e 301 0
26 NAME Corona Australis Cloud MoC 19 01 51 -36 58.9           ~ 554 0
27 V* R CrA Ae* 19 01 53.6764322232 -36 57 08.299341828 12.781 12.651 11.917 11.242 10.412 B5IIIpe 499 2
28 NAME Coronet Cluster Cl* 19 01 54 -36 57.2           ~ 106 1
29 V* T CrA Ae* 19 01 58.777008 -36 57 49.93704   14.087 13.130 11.823 10.678 F5? 179 0
30 HD 177076 Y*O 19 04 44.4144452256 -36 50 40.971078168   8.28 8.12     A0V 30 0
31 NAME CrA Complex reg 19 15 00.0 -37 30 00           ~ 118 1
32 NAME Upper CrA As* ~ ~           ~ 22 0

To bookmark this query, right click on this link: simbad:objects in 2025A&A...701A.242R and select 'bookmark this link' or equivalent in the popup menu