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Panchromatic modeling is one of the most powerful tools at our disposal to measure reliably the physical properties of galaxies across cosmic times. We present here an entirely new implementation in python of one such tool: CIGALE. Developed along three main design principles: simplicity, modularity, and efficiency, it has proven to be a versatile code that in addition to estimating the physical properties of galaxies (or regions within galaxies), can generate arbitrary sets of theoretical models or be used as a library to build other tools. Among its defining features, it is a truly panchromatic code ranging from the far-ultraviolet to the radio that takes into account numerous physical components (including active nuclei or synchrotron emission), that can fit non-photometric data, handle upper limits, determine photometric redshifts, and even build mock catalogs.

ABSTRACT The Dwarf Galaxy Survey (DGS) program is studying low-metallicity galaxies using 230 hr of far-infrared (FIR) and submillimetre (submm) photometric and spectroscopic observations of the Herschel Space Observatory and draws from this a rich database of a wide range of wavelengths tracing the dust, gas and stars. This sample of 50 galaxies includes the largest metallicity range achievable in the local Universe including the lowest metallicity ( Z) galaxies, 1/50 Z⊙, and spans four orders of magnitude in star formation rates. The survey is designed to get a handle on the physics of the interstellar medium (ISM) of low metallicity dwarf galaxies, especially their dust and gas properties and the ISM heating and cooling processes. The DGS produces PACS and SPIRE maps of low-metallicity galaxies observed at 70, 100, 160, 250, 350, and 500 μm with the highest sensitivity achievable to date in the FIR and submm. The FIR fine-structure lines, [CII] 158 μm, [OI] 63 μm, [OI] 145 μm, [OIII] 88 μm, [NIII] 57 μm, and [NII] 122 and 205 μm have also been observed with the aim of studying the gas cooling in the neutral and ionized phases. The SPIRE FTS observations include many CO lines ( J = 4-3 to J = 13-12), [NII] 205 μm, and [CI] lines at 370 and 609 μm. This paper describes the sample selection and global properties of the galaxies and the observing strategy as well as the vast ancillary database available to complement the Herschel observations. The scientific potential of the full DGS survey is described with some example results included.

After finding an error in the procedure for computing the stellar masses of the Dwarf Galaxy Survey sample, we present here the correct values for the stellar masses.

We present measurements of the relation between X-ray luminosity and star formation activity for a sample of normal galaxies spanning the redshift range between 0 and 0.25. We use data acquired by SRG/eROSITA for the performance and verification phase program called eROSITA Final Equatorial Depth Survey (eFEDS). The eFEDS galaxies are observed in the 0.2-2.3 keV band. Making use of a wide range of ancillary data, spanning from the ultraviolet (UV) to mid-infrared wavelengths (MIR), we estimated the star formation rate (SFR) and stellar mass (\\(M_{star}\\)) of 888 galaxies, using Code Investigating GALaxy Emission (CIGALE). We divided our sample of normal galaxies in star-forming (SFGs) and quiescent galaxies according to their position on the main sequence. We confirm a linear correlation between the X-ray luminosity and the SFR for our sample of SFGs, as shown previously in the literature. However, we find this relation to be strongly biased by the completeness limit of the eFEDS survey. Correcting for completeness, we find the fitted relation to be consistent with the literature. We also investigated the relation between X-ray emission from both LMXBs and HMXBs populations with \\(M_{star}\\) and SFR, respectively. Correcting for completeness, we find our fitted relation to considerably scatter from the literature relation at high specific SFR (\\(SFR/M_{star}\\)). We conclude that without accounting for X-ray non-detections, it is not possible to employ eFEDS data to study the redshift evolution of the LMXBs and HMXBs contributions due to completeness issues. Furthermore, we find our sources to largely scatter from the expected Lx/SFR vs specific SFR relation at high redshift. We discuss the dependence of the scatter on the stellar mass, metallicity, or the globular cluster content of the galaxy.

In this work, we study the relation of cosmic environment and morphology with the star-formation (SF) and the stellar population of galaxies. Most importantly, we examine if this relation differs for systems with active and non-active supermassive black holes. For that purpose, we use 551 X-ray detected active galactic nuclei (AGN) and 16,917 non-AGN galaxies in the COSMOS-Legacy survey, for which the surface-density field measurements are available. The sources lie at redshift of \\(\\rm 0.343\\)) and non-AGN galaxies have similar SFR. We, also, examine the stellar populations and the morphology of the sources in different cosmic fields. For the same morphological type, non-AGN galaxies tend to have older stellar populations and are less likely to have undergone a recent burst in denser environments compared to their field counterparts. The differences in the stellar populations with the density field are, mainly, driven by quiescent systems. Moreover, low L\\(_X\\) AGN present negligible variations of their stellar populations, in all cosmic environments, whereas moderate L\\(_X\\) AGN have, on average, younger stellar populations and are more likely to have undergone a recent burst, in high density fields. Finally, in the case of non-AGN galaxies, the fraction of bulge-dominated (BD) systems increases with the density field, while BD AGN are scarce in denser environments. Our results are consistent with a scenario in which a common mechanism, such as mergers, triggers both the SF and the AGN activity.

Recycled dwarf galaxies can form in the collisional debris of massive galaxies. Theoretical models predict that, contrary to classical galaxies, they should be free of non-baryonic Dark Matter. Analyzing the observed gas kinematics of such recycled galaxies with the help of a numerical model, we demonstrate that they do contain a massive dark component amounting to about twice the visible matter. Staying within the standard cosmological framework, this result most likely indicates the presence of large amounts of unseen, presumably cold, molecular gas. This additional mass should be present in the disks of their progenitor spiral galaxies, accounting for a significant part of the so-called missing baryons.

We use \\(\\sim 1800\\) X-ray Active Galactic Nuclei (AGN) in the eROSITA Final Equatorial-Depth Survey (eFEDS), that span over two orders of magnitude in X-ray luminosity, \\(\\rm L_{X,2-10keV} \\approx 10^{43-45}\\,ergs^{-1}\\), and compare their star-formation rate (SFR) relative to that of non-AGN star-forming systems, at \\(\\rm 0.5 10^{44.2}\\,ergs^{-1}\\), the SFR of AGN appears enhanced, by \\(\\sim 30\\%\\), compared to that of star-forming sources, for systems with stellar mass, \\(\\rm 10.5 < log\\,[M_*(M_\\odot)] < 11.5\\), confirming indications found in previous studies. The most massive sources \\(\\rm log\\,[M_*(M_\\odot)] > 11.5\\), present a flat SFR\\(_{norm}\\)-L\\(_X\\) relation up to \\(\\rm L_{X,2-10keV} \\sim 10^{44.5}\\,ergs^{-1}\\), with SFR similar to that of star-forming galaxies. However, at higher L\\(_X\\) (\\(\\rm L_{X,2-10keV} \\sim 10^{45}\\,ergs^{-1}\\)), we find indications that the SFR of these massive AGN hosts may be enhanced compared to that of non-AGN systems.

The detection with of the Atacama Large Millimeter Array (ALMA) of dust-rich high redshift galaxies whose cold dust emission is spatially disconnected from the ultraviolet emission bears a challenge for modelling their spectral energy distributions (SED) with codes based on an energy budget between the stellar and dust components. We test the validity of energy balance modelling on a nearby resolved galaxy with vastly different ultraviolet and infrared spatial distributions and infer what information can be reliably retrieved from the analysis of the full spectral energy distribution. We use 15 broadband images of the Antennae Galaxies ranging from far-ultraviolet to far-infrared and divide Arp 244 into 58 square ~1 kpc\\(^2\\) regions. We fit the data with CIGALE to determine the star formation rate, stellar mass and dust attenuation of each region. We compare these quantities for the addition of the 58 regions to the ones obtained for Arp 244 as a whole and find that both estimates are consistent within one sigma. We present the spatial distribution of these physical parameters as well as the shape of the attenuation curve across the Antennae Galaxies . We also observe a flattening of the attenuation curves with increasing attenuation and dust surface density in agreement with the predictions of hydrodynamical simulations coupled with radiative transfer modelling.

We use AGN with \\(\\rm L_{X} \\sim 10^{42.5-44}\\,erg\\,s^{-1}\\), from the COSMOS-Legacy survey that lie within the UltraVISTA region and cross match them with the LEGA-C catalogue. The latter provides measurements of the calcium break, D\\(_n\\)4000, and H\\(_\\delta\\) Balmer line that allow us to study the stellar populations of AGN and compare them with a galaxy reference catalogue. Our samples consist of 69 AGN and 2176 non-AGN systems, within \\(\\rm 0.6

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