Multi-mission view of extragalactic black hole X-ray binaries LMC X-1 and LMC X-3: Evolution of broadband spectral features

Extragalactic black hole X-ray binaries LMC X-1 and X-3 are the persistent sources, usually found in soft spectral state. We present results from timing study of these sources using MAXI, NICER, NuSTAR AstroSat observations carried out during 2014-2020. Study long-term MAXI lightcurve shows that fractional variability flux 2-10keV is moderate ($\sim$20%) LMCX-1 high ($\sim$50%) LMCX-3. The energy spectra both characterized by a disc blackbody Comptonization component with having an additional Fe-line emission feature. NICER (0.3-10keV), (3.0-40keV) (0.5-20keV) analysis collectively show remained state (disc contribution $f_{disc}>80$%, photon index$\Gamma\sim2.06-4.08$) throughout Mass accretion rate, $\dot{M}$ calculated bolometric luminosity (0.1-50keV) to be within $0.07-0.24\dot{M}_{Edd}$ (Eddington mass rate). Although ($f_{disc}>95\%,\Gamma\sim2.3$) most time, it exhibits transition into intermediate ($f_{disc}=47-73\%,\Gamma\sim2.02-2.36$) hard ($f_{disc}\sim26\%,\Gamma\sim1.6$). through different states varies $0.01-0.42\dot{M}_{Edd}$. Temporal Power Density Spectra (PDS) 0.3-10keV follow red-noise rms 2% for case X-3, 0.08-2.35% state, but relatively intermediate(3.05-4.91%) state($\sim$17.06%). From continuum-fitting method we constrain spin 0.85-0.94 0.16-0.33 respectively fitting method, 0.93-0.94. Finally, discuss implication our findings context dynamics around vicinity BHs.