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The global Schmidt law of star formation provides a power-law relation between the surface densities of star-formation rate (SFR) and gas, and successfully explains plausible scenarios of galaxy formation and evolution. However, star formation being a multi-scale process, requires spatially-resolved analysis for a better understanding of the physics of star formation. It has been shown that the removal of a diffuse background from SFR tracers, such as H$alpha$, far-ultraviolet (FUV), infrared, leads to an increase in the slope of the sub-galactic Schmidt relation. We reinvestigate the local Schmidt relations in nine nearby spiral galaxies taking into account the effect of inclusion and removal of diffuse background in SFR tracers as well as in the atomic gas.We used multiwavelength data obtained as part of the surveys such as SINGS, KINGFISH, THINGS, and HERACLES. Making use of a novel split of the overall light distribution as a function of spatial scale, we subtracted the diffuse background in the SFR tracers as well as the atomic gas. Using aperture photometry, we study the Schmidt relations on background subtracted and unsubtracted data at physical scales varying between 0.5--2 kpc. The fraction of diffuse background varies from galaxy to galaxy and accounts to $sim$34 % in H$alpha$, $sim$43 % in FUV, $sim$37 % in 24 $mu$m, and $sim$75% in H I on average. We find that the inclusion of diffuse background in SFR tracers leads to a linear molecular gas Schmidt relation and a bimodal total gas Schmidt relation. However, the removal of diffuse background in SFR tracers leads to a super-linear molecular gas Schmidt relation. A further removal of the diffuse background from atomic gas results in a slope $sim$1.4 $pm$ 0.1, which agrees with dynamical models of star formation accounting for flaring effects in the outer regions of galaxies.
We present a $^{13}mathrm{CO} (J = 1 rightarrow 0)$ mapping survey of 12 nearby galaxies from the CARMA STING sample. The line intensity ratio $mathcal{R} equiv I[^{12}mathrm{CO} (J = 1 rightarrow 0)]/I[^{13}mathrm{CO} (J = 1 rightarrow 0)]$ is deriv
Exploiting the sample of 30 local star-forming, undisturbed late-type galaxies in different environments drawn from the GAs Stripping Phenomena in galaxies with MUSE (GASP), we investigate the spatially resolved Star Formation Rate-Mass ({Sigma}SFR-{
We report two-dimensional spectroscopic analysis of massive red spiral galaxies ($M_{*}$ $>$ 10$^{10.5}$ $M_{odot}$) and compare them to blue spiral and red elliptical galaxies above the same mass limit based on the public SDSS DR15 MaNGA observation
We present spatially resolved BPT mapping of the extended narrow line regions (ENLRs) of seven nearby Seyfert 2 galaxies, using HST narrow band filter imaging. We construct the BPT diagrams using $leq$ 0.1 resolution emission line images of [O III]$l
Dust attenuation in star-forming spiral galaxies affects stars and gas in different ways due to local variations in dust geometry. We present spatially resolved measurements of dust attenuation for a sample of 232 such star-forming spiral galaxies, d