We present, for the first time, model spectra of single-age, single-metallicity stellar populations computed with the E-MILES evolutionary synthesis code incorporating an environment-dependent, variable galaxy-wide initial mass function (gwIMF). This gwIMF, calculated using the GalIMF code, is rooted in the integrated galactic initial mass function (IGIMF) theory, which predicts IMF variations as a function of the star formation rate and the metallicity. By coupling these two codes, we generated a comprehensive library of single-burst stellar population spectra uniquely sensitive to gwIMF
O ne of the key challenges in astronomy is to measure accurate distances to celestial objects. Knowing distances is crucial since it allows us to measure physical properties such as size, mass and luminosity. Since we can’t go out and use a tape-measure, a range of different approaches have been developed. Many of these approaches rely on using “standard candles”. Standard candles are objects (for example stars or supernovae) for which we know their intrinsic ”true” brightness. Once we know this, then their observed brightness compared to their intrinsic brightness gives us a distance to the
The rocky planet GJ 1132 b, with Earth-like mass and radius, is a prime candidate for atmospheric studies. Previous observations with Hubble and JWST yielded conflicting results about its atmosphere. This study used three transit observations with the CRIRES+ instrument to search for He i, HCN, CH₄, and H₂O in GJ 1132 b's atmosphere. No clear atmospheric signals were detected, but upper limits for CH₄, HCN, and H₂O were established. The results suggest that if GJ 1132 b has an atmosphere, it is not dominated by hydrogen. The work highlights the challenges of detecting high molecular weight