Description
In this talk, I will present a first-of-its-kind map of Star Formation Efficiency (SFE) across a high-redshift galaxy. SFE is defined as the star formation rate (SFR) divided by the total gas mass of the ISM, computed per unit area (i.e., SFE = Σ_SFR/ Σ_Mgas). SDP81, located at z = 3.042, is an ideal candidate for this study because the magnification from gravitational lensing allows us to probe the galaxy at a scale of approximately 500 parsecs. Using new ALMA Band 10 observations, we can now explore both sides of the spectral energy distribution (SED) bump located at a rest-frame wavelength of approximately 160 microns for the first time. Through SED fitting, we will first investigate if there is any variation in dust temperature across the galaxy and subsequently estimate dust mass within a given area. This dust mass will then serve as a tracer for the total gas mass in those areas. The bolometric luminosity obtained by integrating the SED over the frequency range accounts for the total radiation emitted by dust. Using an assumed IMF and the bolometric luminosity, we can estimate the star formation rate for this galaxy and, consequently, the star formation efficiency per unit area.
