SIMBAD references

Using near-infrared data from the Two Micron All Sky Survey catalog and the Near Infrared Color Excess method, we studied the extinction distribution in five dense cores of Musca, which show visual extinction greater than 10 mag and are potential sites of star formation. We analyzed the stability in four of them, fitting their radial extinction profiles with Bonnor-Ebert isothermal spheres, and explored their properties using the J = 1-0 transition of ¹³CO and C¹⁸O and the J = K = 1 transition of NH₃. One core is not well described by the model. The stability parameter of the fitted cores ranges from 4.5 to 5.7 and suggests that all cores are stable, including Mu13, which harbors one young stellar object (YSO), the IRAS 12322-7023 source. However, the analysis of the physical parameters shows that Mu13 tends to have larger A_V, n_c, and P_ext than the remaining starless cores. The other physical parameters do not show any trend. It is possible that those are the main parameters to explore in active star-forming cores. Mu13 also shows the most intense emission of NH₃. Its ¹³CO and C¹⁸O lines have double peaks, whose integrated intensity maps suggest that they are due to the superposition of clouds with different radial velocities seen in the line of sight. It is not possible to state whether these clouds are colliding and inducing star formation or are related to a physical process associated with the formation of the YSO.