2 research outputs found
OH maser towards IRAS 06056+2131: polarization parameters and evolution status
We present high angular resolution observations of OH maser emission towards
the high-mass star forming region IRAS 06056+2131. The observations were
carried out using the UK radio interferometer array, Multi-Element Radio Linked
Interferometer Network (MERLIN) in the OH main lines at 1665- and 1667-MHz, in
addition to the OH satellite line at 1720-MHz. The results of this study
revealed emission in the 1665 MHz line with an estimated total intensity of
Jy. We did not detect any emission from the 1667-MHz and 1720-MHz
lines.
The full polarization mode of MERLIN enables us to investigate the magnetic
field in the OH maser region. Our results show that IRAS 06056+2131 is a highly
circularly polarized source. In this transition, a Zeeman pair is identified
from which a magnetic strength of mG is inferred. The orientation
of the linear polarization vectors suggests that the magnetic field lines at
the location of the OH maser emission \textbf{might be} in agreement with the
orientation of the outflow thought to be associated with this source. The star
forming evolutionary status of the embedded proto-stellar object is discussed.Comment: 10 pages, 5 figure
Analysis of the fractional relativistic polytropic gas sphere
Abstract Many stellar configurations, including white dwarfs, neutron stars, black holes, supermassive stars, and star clusters, rely on relativistic effects. The Tolman–Oppenheimer–Volkoff (TOV) equation of the polytropic gas sphere is ultimately a hydrostatic equilibrium equation developed from the general relativity framework. In the modified Riemann Liouville (mRL) frame, we formulate the fractional TOV (FTOV) equations and introduce an analytical solution. Using power series expansions in solving FTOV equations yields a limited physical range to the convergent power series solution. Therefore, combining the two techniques of Euler–Abel transformation and Padé approximation has been applied to improve the convergence of the obtained series solutions. For all possible values of the relativistic parameters ( σ ), we calculated twenty fractional gas models for the polytropic indexes n = 0, 0.5, 1, 1.5, 2. Investigating the impacts of fractional and relativistic parameters on the models revealed fascinating phenomena; the two effects for n = 0.5 are that the sphere’s volume and mass decrease with increasing σ and the fractional parameter ( α ). For n = 1, the volume decreases when σ  = 0.1 and then increases when σ  = 0.2 and 0.3. The volume of the sphere reduces as both σ and α increase for n = 1.5 and n = 2. We calculated the maximum mass and the corresponding minimum radius of the white dwarfs modeled with polytropic index n = 3 and several fractional and relativistic parameter values. We obtained a mass limit for the white dwarfs somewhat near the Chandrasekhar limit for the integer models with small relativistic parameters ( α = 1 , σ = 0.001 ). The situation is altered by lowering the fractional parameter; the mass limit increases to Mlimit = 1.63348 M⊙ at α = 0.95 and σ = 0.001