Hot Corino Chemistry in the Class I Binary Source Ser-emb 11

We report the detection of more than 120 emission lines corresponding to eight complex organic molecules (COMs; CH3OH, CH3CH2OH, CH3OCH3, CH3OCHO, CH3COCH3, NH2CHO, CH2DCN, and CH3CH2CN) and three isotopologues (CH2DOH, 13CH3CN, and CH3C15N) toward the western component of the Ser-emb 11 binary young stellar object using observations with the Atacama Large Millimeter/submillimeter Array at ∼1 mm. The complex organic emission was unresolved with a ∼0.″5 beam (∼220 au) in a compact region around the central protostar, and a population diagram analysis revealed excitation temperatures above 100 K for all COMs, indicating the presence of a hot corino. The estimated column densities were in the range of 1017−1018 cm−2 for the O-bearing COMs, and three orders of magnitude lower for the N-bearing species. We also report the detection of H2CO and CH3OH emission in a nearby millimeter source that had not been previously cataloged. Ser-emb 11 is classified in the literature as a Class I source near the Class 0/I cutoff. The estimated COM relative abundances in Ser-emb 11 W and the other three Class I hot corino sources reported in the literature are consistent with those of Class 0 hot corinos, suggesting a continuity in the chemical composition of hot corinos during protostellar evolution.

Isotropic uncharged model with compactness and stable configurations

In this study we have obtained a new exact model for relativistic stellar object by solving Einstein’s field equation with help of Buchdahl metric. The model is capable to represent some known compact stars like Her X-1,4U 1538-52 and SAX J1808.4-3658. The model satisfies the regularity, casuality, stability and energy conditions. Using the Tolman–Oppenheimer–Volkoff equations, we explore the hydrostatic equilibrium for an uncharged case. We have also compared these conditions with graphical representations that provide strong evidences for more realistic and viable models.