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The study of galaxy evolution hinges on our ability to interpret multi-wavelength galaxy observations in terms of their physical properties. To do this, we rely on spectral energy distribution (SED) models which allow us to infer physical parameters from spectrophotometric data. In recent years, thanks to the wide and deep multi-waveband galaxy surveys, the volume of high quality data have significantly increased. Alongside the increased data, algorithms performing SED fitting have improved, including better modeling prescriptions, newer templates, and more extensive sampling in wavelength space. We present a comprehensive analysis of different SED fitting codes including their methods and output with the aim of measuring the uncertainties caused by the modeling assumptions. We apply fourteen of the most commonly used SED fitting codes on samples from the CANDELS photometric catalogs at z~1 and z~3. We find agreement on the stellar mass, while we observe some discrepancies in the star formation rate (SFR) and dust attenuation results. To explore the differences and biases among the codes, we explore the impact of the various modeling assumptions as they are set in the codes (e.g., star formation histories, nebular, dust, and AGN models) on the derived stellar masses, SFRs, and A_V values. We then assess the difference among the codes on the SFR-stellar mass relation and we measure the contribution to the uncertainties by the modeling choices (i.e., the modeling uncertainties) in stellar mass (~0.1dex), SFR (~0.3dex), and dust attenuation (~0.3mag). Finally, we present some resources summarizing best practices in SED fitting., 25 pages, 11 figures. Accepted for publication in ApJ

We report the discovery of a candidate galaxy with a photo-z of z~12 in the first epoch of the JWST Cosmic Evolution Early Release Science (CEERS) Survey. Following conservative selection criteria we identify a source with a robust z_phot = 11.8^+0.3_-0.2 (1-sigma uncertainty) with m_F200W=27.3, and >7-sigma detections in five filters. The source is not detected at lambda < 1.4um in deep imaging from both HST and JWST, and has faint ~3-sigma detections in JWST F150W and HST F160W, which signal a Ly-alpha break near the red edge of both filters, implying z~12. This object (Maisie's Galaxy) exhibits F115W-F200W > 1.9 mag (2-sigma lower limit) with a blue continuum slope, resulting in 99.6% of the photo-z PDF favoring z > 11. All data quality images show no artifacts at the candidate's position, and independent analyses consistently find a strong preference for z > 11. Its colors are inconsistent with Galactic stars, and it is resolved (r_h = 340 +/- 14 pc). Maisie's Galaxy has log M*/Msol ~ 8.5 and is highly star-forming (log sSFR ~ -8.2 yr^-1), with a blue rest-UV color (beta ~ -2.5) indicating little dust though not extremely low metallicity. While the presence of this source is in tension with most predictions, it agrees with empirical extrapolations assuming UV luminosity functions which smoothly decline with increasing redshift. Should followup spectroscopy validate this redshift, our Universe was already aglow with galaxies less than 400 Myr after the Big Bang., 17 pages, 6 figures, 3 tables, ApJL in press. Summary of changes from original submission: Improvements in astrometry generated a weak detection in F150W that reduces the photo-z to 11.8 but does not increase the likelihood of lower-z solutions. A full discussion of changes from the original version is available at: https://web.corral.tacc.utexas.edu/ceersdata/papers/Maisie_update.pdf

In order to understand the interaction between the central black hole and the whole galaxy or their co-evolution history along with cosmic time, a complete census of active galactic nuclei (AGN) is crucial. However, AGNs are often missed in optical, UV and soft X-ray observations since they could be obscured by gas and dust. A mid-infrared (mid-IR) survey supported by multiwavelength data is one of the best ways to find obscured AGN activities because it suffers less from extinction. Previous large IR photometric surveys, e.g., $WISE$ and $Spitzer$, have gaps between the mid-IR filters. Therefore, star forming galaxy (SFG)-AGN diagnostics in the mid-IR were limited. The $AKARI$ satellite has a unique continuous 9-band filter coverage in the near to mid-IR wavelengths. In this work, we take advantage of the state-of-the-art spectral energy distribution (SED) modelling software, CIGALE, to find AGNs in mid-IR. We found 126 AGNs in the NEP-Wide field with this method. We also investigate the energy released from the AGN as a fraction of the total IR luminosity of a galaxy. We found that the AGN contribution is larger at higher redshifts for a given IR luminosity. With the upcoming deep IR surveys, e.g., $JWST$, we expect to find more AGNs with our method., 14 pages, 18 figures. Accepted for publication in MNRAS. For associated video, please see https://www.youtube.com/watch?v=B01jL0Bol9Q&feature=emb_logo

Studying the UV dust attenuation, as well as its relation to other galaxy parameters such as the stellar mass, plays an important role in multi-wavelength research. This work relates the dust attenuation to the stellar mass of star forming galaxies, and its evolution with redshift. A sample of galaxies with an estimate of the dust attenuation computed from the infrared excess was used. The dust attenuation vs. stellar mass data, separated in redshift bins, was modelled by a single parameter linear function, assuming a nonzero constant apparent dust attenuation for low mass galaxies. But the origin of this effect is still to be determined and several possibilities are explored (actual high dust content, variation of the dust-to-metal ratio, variation of the stars-dust geometry). The best-fitting parameter of this model is then used to study the redshift evolution of the cosmic dust attenuation and is found to be in agreement with results from the literature. This work also gives evidence to a redshift evolution of the dust attenuation - stellar mass relationship, as is suggested by recent works in the highest redshift range., Comment: 10 pages, 6 figures

The aim of this study is to characterize the physical and statistical properties of a sample of infrared-bright dust-obscured galaxies (DOGs) by fitting their spectral energy distributions (SEDs). We examined 28 DOGs at redshifts 0.47 ≤ z ≤ 1.63 discovered by combining images of the Subaru Hyper Suprime-Cam (HSC) survey, the VISTA Kilo-degree Infrared Galaxy (VIKING) survey, and the Wide-field Infrared Survey Explorer (WISE) all-sky survey, and detected at Herschel Spectral and Photometric Imaging Receiver (SPIRE) bands. We have detected a significant active galactic nucleus (AGN) contribution to the mid-infrared luminosity for $71\%$ of DOGs. Our DOGs contain several types of AGNs; the majority of AGN emission originates from Type 2 AGNs. Our DOG sample shows very high values of stellar mass [log (M*/M${}_\odot $) = 11.49 ± 1.61] compared with other samples of DOGs selected at infrared wavelengths. Our study is promising to identify a new type of DOGs called “overweight” DOGs (ODOGs). ODOGs may indicate the end of the DOG phase, and then they become visible quasars. Principal component (PC) analysis is applied to reduce the number of dimensions of our sample, removing the dependency on the observed variables. There are two significant PCs describing $72.7\%$ of the total variance. The first PC strongly correlates with redshift, dust luminosity, dust mass, and stellar mass, while far-ultraviolet (FUV) attenuation strongly correlates with the second PC, which is orthogonal to the first one. The partial correlation between the resulted physical parameters is tested, supporting the reliability of the correlations.

Modern and future surveys effectively provide a panchromatic view for large numbers of extragalactic objects. Consistently modeling these multiwavelength survey data is a critical but challenging task for extragalactic studies. The Code Investigating GALaxy Emission (cigale) is an efficient python code for spectral energy distribution (SED) fitting of galaxies and active galactic nuclei (AGNs). Recently, a major extension of cigale (named x-cigale) has been developed to account for AGN/galaxy X-ray emission and improve AGN modeling at UV-to-IR wavelengths. Here, we apply x-cigale to different samples, including Cosmological Evolution Survey (COSMOS) spectroscopic type 2 AGNs, Chandra Deep Field-South X-ray detected normal galaxies, Sloan Digital Sky Survey quasars, and COSMOS radio objects. From these tests, we identify several weaknesses of x-cigale and improve the code accordingly. These improvements are mainly related to AGN intrinsic X-ray anisotropy, X-ray binary emission, AGN accretion-disk SED shape, and AGN radio emission. These updates improve the fit quality and allow for new interpretation of the results, based on which we discuss physical implications. For example, we find that AGN intrinsic X-ray anisotropy is moderate, and can be modeled as ${L}_{X}(\theta )\propto 1+\cos \theta $, where θ is the viewing angle measured from the AGN axis. We merge the new code into the major branch of cigale, and publicly release this new version as cigale v2022.0 on https://cigale.lam.fr., G.Y. and C.P. acknowledge support from the George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University, from the National Science Foundation through grants AST1614668 and AST-2009442, and from the NASA/ESA/CSA James Webb Space Telescope through the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-03127. M.B. acknowledges support by the ANID BASAL project FB21000 and the FONDECYT regular grants 1170618 and 1211000. W.N.B. acknowledges the support from NASA grant 80NSSC19K0961. K.M. has been supported by the Polish National Science Centre (UMO2018/30/E/ST9/00082). G.M. acknowledges support by the Agencia Estatal de Investigación, Unidad de Excelencia María de Maeztu, ref. MDM-2017-0765. M.S. acknowledges support by the Ministry of Education, Science and Technological Development of the Republic of Serbia through contract No. 451-03-9/2021-14/200002 and by the Science Fund of the Republic of Serbia, PROMIS 6060916, BOWIE.

There is now ample evidence that dust is already present in abundance at high z. However, given the faintness of distant galaxies in the optical and the NIR, datasets are still limited and how the dust affects the emerging radiation of galaxies at very high redshift is not yet fully understood. Using the ALPINE survey, our objective is to quantify the dust attenuation properties in galaxies at z=4.4-5.5, and in particular the shape of their attenuation curve. Using the CIGALE code, we model the stellar populations and their interaction with the dust in order to measure some of the physical properties of a subsample of 23 main-sequence ALPINE galaxies. We find that the attenuation curves span a broad range of properties, from curves that are much steeper than the SMC extinction curve, to shallower than the starburst attenuation curve. The shape of the attenuation curves strongly depends on the V-band attenuation. Galaxies with the lowest attenuation also present the steepest curves. The steepness of such curves is probably the consequence of the combination of the intrinsic physical properties of the dust, the relative distribution of stars and dust in the interstellar medium, and the differential reddening. The broad range of attenuation curves found at z~5 shows that no single attenuation curve is appropriate for main sequence galaxies and that assuming a fixed curve can lead to large errors, for instance in the interpretation and use of the IRX-beta diagram, if SED modeling is not feasible. Great caution should be exercised when correcting high redshift galaxies for the presence of dust using the UV slope beta as it can affect the estimation of both SFR and stellar mass even at low V-band attenuation due to the steepness of the attenuation curve. However, when SED modeling can be used, the impact of the choice of the attenuation curve on the SFR and the stellar mass is limited., Comment: 20 pages, 14 figures. Accepted for publication in A&A

We present an investigation into the first 500 Myr of galaxy evolution from the Cosmic Evolution Early Release Science (CEERS) survey. CEERS, one of 13 JWST ERS programs, targets galaxy formation from z~0.5 to z>10 using several imaging and spectroscopic modes. We make use of the first epoch of CEERS NIRCam imaging, spanning 35.5 sq. arcmin, to search for candidate galaxies at z>9. Following a detailed data reduction process implementing several custom steps to produce high-quality reduced images, we perform multi-band photometry across seven NIRCam broad and medium-band (and six Hubble broadband) filters focusing on robust colors and accurate total fluxes. We measure photometric redshifts and devise a robust set of selection criteria to identify a sample of 26 galaxy candidates at z~9-16. These objects are compact with a median half-light radius of ~0.5 kpc. We present an early estimate of the z~11 rest-frame ultraviolet (UV) luminosity function, finding that the number density of galaxies at M_UV ~ -20 appears to evolve very little from z~9 to z~11. We also find that the abundance (surface density [arcmin^-2]) of our candidates exceeds nearly all theoretical predictions. We explore potential implications, including that at z>10 star formation may be dominated by top-heavy initial mass functions, which would result in an increased ratio of UV light per unit halo mass, though a complete lack of dust attenuation and/or changing star-formation physics may also play a role. While spectroscopic confirmation of these sources is urgently required, our results suggest that the deeper views to come with JWST should yield prolific samples of ultra-high-redshift galaxies with which to further explore these conclusions., 41 pages, 20 figures, 6 tables, submitted to ApJL. Key results in Figures 13-15, discussed in Sections 7 and 8

We perform SED fitting analysis on a COSMOS sample covering UV-to-FIR wavelengths with emission lines from the FMOS survey. The sample of 182 objects with H$\alpha$ and [OIII]$\lambda5007$ emission spans over a range of $1.40, Comment: Accepted for publication in A&A, 17 pages, 19 figures

Aims. We study how the upcoming Legacy Survey of Space and Time (LSST) data from the Vera C. Rubin Observatory can be employed to constrain the physical properties of normal star-forming galaxies (main-sequence galaxies). Because the majority of the observed LSST objects will have no auxiliary data, we use simulated LSST data and existing real observations to test the reliability of estimates of the physical properties of galaxies, such as their star formation rate (SFR), stellar mass (Mstar), and dust luminosity (Ldust). We focus on normal star-forming galaxies because they form the majority of the galaxy population in the universe and are therefore more likely to be observed with the LSST. Methods. We performed a simulation of LSST observations and uncertainties of 50 385 real galaxies within the redshift range 0 z Herschel Extragalactic Legacy Project (HELP) survey. Our analysis focused on two fields, ELAIS N1 and COSMOS. To obtain the physical properties of the galaxies, we fit their spectral energy distributions (SEDs) using the Code Investigating GALaxy Emission. We simulated the LSST data by convolving the SEDs fitted by employing the multi-wavelength observations. We compared the main galaxy physical properties, such as SFR, Mstar, and Ldust obtained from the fit of the observed multi-wavelength photometry of galaxies (from the UV to the far-IR) to those obtained from the simulated LSST optical measurements alone. Results. We present the catalogue of simulated LSST observations for 23 291 main-sequence galaxies in the ELAIS N1 field and for 9093 galaxies in the COSMOS field. It is available in the HELP virtual observatory. The stellar masses estimated based on the LSST measurements agree with the full UV to far-IR SED estimates because they mainly depend on the UV and optical emission, which is well covered by LSST in the considered redshift range. Instead, we obtain a clear overestimate of the dust-related properties (SFR, Ldust, Mstar) estimated with the LSST alone. They are highly correlated with redshift. We investigate the cause of this overestimate and conclude that it is related to an overestimate of the dust attenuation in both UV and near-IR. We find that it is necessary to employ auxiliary rest-frame mid-IR observations, simulated UV observations, or the far-UV attenuation (AFUV)-Mstar relation to correct for the overestimate. We also deliver the correction formula log10(SFRLSST/SFRreal) = 0.26 ⋅ z2 − 0.94 ⋅ z + 0.87. It is based on the 32 384 MS galaxies detected with Herschel.

We study the galaxy merger fraction and its dependence on star formation mode in the5.4 square degrees of the North Ecliptic Pole-Wide field. We select 6352 galaxies withAKARI 9{\mu}m detections, and identify mergers among them using the Gini coefficientand M20derived from the Subaru/HSC optical images. We obtain the total infraredluminosity and star formation rate of galaxies using the spectral energy distributiontemplates based on one band, AKARI 9{\mu}m. We classify galaxies into three differentstar formation modes (i.e. starbursts, main sequence, and quiescent galaxies) andcalculate the merger fractions for each. We find that the merger fractions of galaxiesincrease with redshift atz, Comment: 13 pages, 11 figures, Accepted for publication by MNRAS

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.

At high redshift, the contribution of strong emission lines to the broadband photometry can cause large uncertainties when estimating galaxy physical properties. To examine this effect, we investigate a sample of 54 LBGs at 3 < zspec < 3.8 with detected [OIII] line emissions. We use CIGALE to fit simultaneously the rest-frame UV-to-NIR SEDs of these galaxies and their emission line data. By comparing the results with and without emission line data, we show that spectroscopic data are necessary to constrain the nebular model. We examine the K-band excess, which is usually used to estimate the emissions of [OIII]+Hβ lines when there is no spectral data, and find that the difference between the estimation and observation can reach up to > 1 dex for some galaxies, showing the importance of obtaining spectroscopic measurements of these lines. We also estimate the equivalent width of the Hβ absorption and find it negligible compared to the Hβ emission.

We revisit the dependence of covering factor (CF) of dust torus on physical properties of active galactic nuclei (AGNs) by taking into account an AGN polar dust emission. The CF is converted from a ratio of infrared (IR) luminosity contributed from AGN dust torus ($L_{\rm IR}^{\rm torus}$) and AGN bolometric luminosity ($L_{\rm bol}$), by assuming a non-linear relation between luminosity ratio and intrinsic CF. We select 37,181 type 1 quasars at $z < 0.7$ from the Sloan Digital Sky Survey Data Release 16 quasar catalog. Their $L_{\rm bol}$, black hole mass ($M_{\rm BH}$), and Eddington ratio ($\lambda_{\rm Edd}$) are derived by spectral fitting with QSFit. We conduct spectral energy distribution decomposition by using X-CIGALE with clumpy torus and polar dust model to estimate $L_{\rm IR}^{\rm torus}$ without being affected by the contribution of stellar and AGN polar dust to IR emission. For 5720 quasars whose physical quantities are securely determined, we perform a correlation analysis on CF and (i) $L_{\rm bol}$, (ii) $M_{\rm BH}$, and (iii) $\lambda_{\rm Edd}$. As a result, anti-correlations for CF-$L_{\rm bol}$, CF-$M_{\rm BH}$, and CF-$\lambda_{\rm Edd}$ are confirmed. We find that incorporating the AGN polar dust emission makes those anti-correlations stronger which are compared to those without considering it. This indicates that polar dust wind provably driven by AGN radiative pressure is one of the key components to regulate obscuring material of AGNs., Comment: 20 pages, 14 figures, and 4 tables, accepted for publication in ApJ. Physical properties (e.g., BH mass, Eddington ratio, IR luminosity) of 37,181 quasars at z < 0.7 selected from the SDSS DR16 will be available as a Machine-readable table

In this work we report the discovery of the hyperluminous galaxy HELP_J100156.75+022344.7 at the photometric redshift of z ~ 4.3. The galaxy was discovered in the Cosmological Evolution Survey (COSMOS) field, one of the fields studied by the Herschel Extragalactic Legacy Project (HELP). We present the spectral energy distribution (SED) of the galaxy and fit it with the CYprus models for Galaxies and their NUclear Spectra (CYGNUS) multi-component radiative transfer models. We find that its emission is dominated by an obscured quasar with a predicted total 1-1000um luminosity of $3.91^{+1.69}_{-0.55} \times 10^{13} L_\odot$ and an active galactic nucleus (AGN) fraction of ~89%. We also fit HELP_J100156.75+022344.7 with the Code Investigating GALaxy Emission (CIGALE) code and find a similar result. This is only the second z > 4 hyperluminous obscured quasar discovered to date. The discovery of HELP_J100156.75+022344.7 in the ~ 2deg^2 COSMOS field implies that a large number of obscured hyperluminous quasars may lie in the HELP fields which cover ~ 1300deg^2. If this is confirmed, tension between supermassive black hole evolution models and observations will be alleviated. We estimate the space density of objects like HELP_J100156.75+022344.7 at z ~ 4.5 to be $\sim 1.8 \times 10^{-8}$Mpc$^{-3}$. This is slightly higher than the space density of coeval hyperluminous optically selected quasars suggesting that the obscuring torus in z > 4 quasars may have a covering factor $\gtrsim 50\%$., Accepted for publication in Monthly Notices of the Royal Astronomical Society Letters. Models used in this work are available at http://ahpc.euc.ac.cy/

The mid-infrared spectrometer and camera transit spectrometer (MISC-T) is one of the three baseline instruments for Origins Space Telescope (Origins) and provides the capability to assess the habitability of nearby exoplanets and search for signs of life. MISC-T employs a densified pupil optical design, and HgCdTe and Si:As detector arrays. This optical design allows the instrument to be relatively insensitive to minor line-of-sight pointing drifts and telescope aberrations, and the detectors do not require a sub-Kelvin refrigerator. MISC-T has three science spectral channels that share the same field-of-view by means of beam splitters, and all channels are operated simultaneously to cover the full spectral range from 2.8 to 20 μm at once with exquisite stability and precision (

The Origins Space Telescope (Origins) concept is designed to investigate the creation and dispersal of elements essential to life, the formation of planetary systems, and the transport of water to habitable worlds and the atmospheres of exoplanets around nearby K- and M-dwarfs to identify potentially habitable—and even inhabited—worlds. These science priorities are aligned with NASA’s three major astrophysics science goals: How does the Universe work? How did we get here? and Are we alone? We briefly describe the science case that arose from the astronomical community and the science traceability matrix for Origins. The science traceability matrix prescribes the design of Origins and demonstrates that it will address the key science questions motivated by the science case.

The JWST MIRI instrument will revolutionize extragalactic astronomy with unprecedented sensitivity and angular resolution in mid-IR. Here, we assess the potential of MIRI photometry to constrain galaxy properties in the Cosmic Evolution Early Release Science (CEERS) survey. We derive estimated MIRI fluxes from the spectral energy distributions (SEDs) of real sources that fall in a planned MIRI pointing. We also obtain MIRI fluxes for hypothetical AGN-galaxy mixed models varying the AGN fractional contribution to the total IR luminosity ($\rm frac_{AGN}$). Based on these model fluxes, we simulate CEERS imaging (3.6-hour exposure) in 6 bands from F770W to F2100W using MIRISIM, and reduce these data using JWST PIPELINE. We perform PSF-matched photometry with TPHOT, and fit the source SEDs with X-CIGALE, simultaneously modeling photometric redshift and other physical properties. Adding the MIRI data, the accuracy of both redshift and $\rm frac_{AGN}$ is generally improved by factors of $\gtrsim 2$ for all sources at $z\lesssim 3$. Notably, for pure-galaxy inputs ($\rm frac_{AGN}=0$), the accuracy of $\rm frac_{AGN}$ is improved by $\sim 100$ times thanks to MIRI. The simulated CEERS MIRI data are slightly more sensitive to AGN detections than the deepest X-ray survey, based on the empirical $L_{\rm X}$-$L_{\rm 6\mu m}$ relation. Like X-ray observations, MIRI can also be used to constrain the AGN accretion power (accuracy $\approx 0.3$ dex). Our work demonstrates that MIRI will be able to place strong constraints on the mid-IR luminosities from star formation and AGN, and thereby facilitate studies of the galaxy/AGN co-evolution., Comment: 31 pages, 24 figures, 3 tables. Re-submitted to ApJS after revision

The Origins Space Telescope will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. How did galaxies evolve from the earliest galactic systems to those found in the Universe today? How do habitable planets form? How common are life-bearing worlds? To answer these alluring questions, Origins will operate at mid- and far-infrared (IR) wavelengths and offer powerful spectroscopic instruments and sensitivity three orders of magnitude better than that of the Herschel Space Observatory, the largest telescope flown in space to date. We describe the baseline concept for Origins recommended to the 2020 US Decadal Survey in Astronomy and Astrophysics. The baseline design includes a 5.9-m diameter telescope cryocooled to 4.5 K and equipped with three scientific instruments. A mid-infrared instrument (Mid-Infrared Spectrometer and Camera Transit spectrometer) will measure the spectra of transiting exoplanets in the 2.8 to 20 μm wavelength range and offer unprecedented spectrophotometric precision, enabling definitive exoplanet biosignature detections. The far-IR imager polarimeter will be able to survey thousands of square degrees with broadband imaging at 50 and 250 μm. The Origins Survey Spectrometer will cover wavelengths from 25 to 588 μm, making wide-area and deep spectroscopic surveys with spectral resolving power R ∼ 300, and pointed observations at R ∼ 40,000 and 300,000 with selectable instrument modes. Origins was designed to minimize complexity. The architecture is similar to that of the Spitzer Space Telescope and requires very few deployments after launch, while the cryothermal system design leverages James Webb Space Telescope technology and experience. A combination of current-state-of-the-art cryocoolers and next-generation detector technology will enable Origins’ natural background-limited sensitivity.

arXiv:2106.10678v1, We use X-ray active galactic nuclei (AGN) observed by the Chandra X-ray Observatory within the 9.3 deg2 Boötes field of the NDWFS to study whether there is a correlation between X-ray luminosity (LX) and star formation rate (SFR) of the host galaxy, at 0.5, GM acknowledges support by the Agencia Estatal de Investigación, Unidad de Excelencia María de Maeztu, ref. MDM-2017-0765. MB acknowledges FONDECYT regular grant 1170618 The project has received funding from Excellence Initiative of Aix-Marseille University - AMIDEX, a French ‘Investissements d’Avenir’ programme. KM has been supported by the National Science Centre (UMO2018/30/E/ST9/00082).

The Origins Space Telescope (Origins) is one of four science and technology definition studies selected by the National Aeronautics and Space Administration (NASA) in preparation of the 2020 Astronomy and Astrophysics Decadal survey in the US. Origins will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. It is designed to answer three major science questions: How do galaxies form stars, make metals, and grow their central supermassive black holes from reionization? How do the conditions for habitability develop during the process of planet formation? Do planets orbiting M-dwarf stars support life? Origins operates at mid- to far-infrared wavelengths from ~ 2.8 μm to 588 μm, and is more than 1000 times more sensitive than prior far-IR missions due to its cold (~ 4.5 K) aperture and state-of-the-art instruments.

We report new observations toward the hyper-luminous dusty starbursting major merger ADFS-27 (z=5.655), using ATCA and ALMA. We detect CO 2-1, 8-7, 9-8, 10-9 and H2O(321-221) emission, and a P-Cygni-shaped OH+(11-01) absorption/emission feature. We also tentatively detect H2O(321-312) and OH+(12-01) emission and CH+(1-0) absorption. We find a total cold molecular mass of M_gas = (2.1+/-0.2) x 10^11 (alpha_CO/1.0) Msun. We also find that the excitation of the star-forming gas is overall moderate for a z>5 dusty starburst, which is consistent with its moderate dust temperature. A high density, high kinetic temperature gas component embedded in the gas reservoir is required to fully explain the CO line ladder. This component is likely associated with the "maximum starburst" nuclei in the two merging galaxies, which are separated by only (140+/-13) km/s along the line of sight and 9.0 kpc in projection. The kinematic structure of both components is consistent with galaxy disks, but this interpretation remains limited by the spatial resolution of the current data. The OH+ features are only detected towards the northern component, which is also the one that is more enshrouded in dust and thus remains undetected up to 1.6 um even in our sensitive new HST/WFC3 imaging. The absorption component of the OH+ line is blueshifted and peaks near the CO and continuum emission peak while the emission is redshifted and peaks offset by 1.7 kpc from the CO and continuum emission peak, suggesting that the gas is associated with a massive molecular outflow from the intensely star-forming nucleus that supplies 125 Msun/yr of enriched gas to its halo., 20 pages, 11 figures, 6 tables; to appear in the Astrophysical Journal (accepted November 29, 2020)

We propose a new mission called Space Project for Astrophysical and Cosmological Exploration (SPACE) as part on the ESA long term planning Voyage 2050 programme. SPACE will study galaxy evolution at the earliest times, with the key goals of charting the formation of the heavy elements, measuring the evolution of the galaxy luminosity function, tracing the build-up of stellar mass in galaxies over cosmic time, and finding the first super-massive black holes (SMBHs) to form. The mission will exploit a unique region of the parameter space, between the narrow ultra-deep surveys with HST and JWST, and shallow wide-field surveys such as Roman Space Telescope and EUCLID, and should yield by far the largest sample of any current or planned mission of very high redshift galaxies at z > 10 which are sufficiently bright for detailed follow-up spectroscopy. Crucially, we propose a wide-field spectroscopic near-IR + mid-IR capability which will greatly enhance our understanding of the first galaxies by detecting and identifying a statistical sample of the first galaxies and the first SMBH, and to chart the metal enrichment history of galaxies in the early Universe - potentially finding signatures of the very first stars to form from metal-free primordial gas. The wide-field and wavelength range of SPACE will also provide us a unique opportunity to study star formation by performing a wide survey of the Milky Way in the near-IR + mid-IR. This science project can be enabled either by a stand-alone ESA-led M mission or by an instrument for an L mission (with ESA and/or NASA, JAXA and other international space agencies) with a wide-field (sub-)millimetre capability at wavelength > 500 microns., Submitted to Experimental Astronomy as one of the proposals for the European Space Agency Voyage 2050 Programme

The chemical enrichment in the interstellar medium (ISM) of galaxies is regulated by several physical processes: stellar evolution, grain formation and destruction, galactic inflows and outflows. Understanding such processes is essential to follow the chemical enrichment of galaxies through the cosmic epochs, and to interpret the observations. Despite the importance of such topics, the efficiency of the different processes driving the evolution of baryons in galaxies, remain controversial. We revise the current description of metal and dust evolution in local low-metallicity dwarf galaxies and we develop a description for Lyman Break Galaxies. Our main goal is to reproduce i) the peak in the mass of dust over the mass of stars (sMdust) observed within few hundred Myrs; ii) the decrease of the sMdust at later time. The spectral energy distribution of the galaxies is fitted with the "Code Investigating GALaxies Emission" (CIGALE), through which the stellar and dust masses, and the star formation rate are estimated. For some of the dwarf galaxies, the metal and gas content are also available. We run different calculations of chemical evolution in galaxies, and we fit the observed properties through the model predictions. We show that i) a top-heavy initial mass function that favours massive stars and a dust condensation fraction for Type II Supernovae (SNe II) of 50% or more help to reproduce the peak of sMdust observed after 100 Myrs since the beginning of the cycle; ii) galactic outflows play a crucial role in reproducing the decline in sMdust with age, and they are more efficient than grain destruction from SNe II; iii) a star formation efficiency (mass of gas converted into stars) of few per cent is required to explain the metallicity of local dwarf galaxies; iv) dust growth in the ISM is not necessary to reproduce the sMdust and, if present, its effect is erased by galactic outflows., 28 pages, 17 figures, accepted for publication in A&A

[Abridged] We discovered in the Herschel Reference Survey an extremely bright IR source with $S_{500}$~120mJy (Red Virgo 4 - RV4). Based on IRAM/EMIR and IRAM/NOEMA detections of the CO(5-4), CO(4-3), and [CI] lines, RV4 is located at z=4.724, yielding a total observed L$_{IR}$ of 1.1+/-0.6x0$^{14}$L$_{\odot}$. At the position of the Herschel emission, three blobs are detected with the VLA at 10cm. The CO(5-4) line detection of each blob confirms that they are at the same redshift with the same line width, indicating that they are multiple images of the same source. In Spitzer and deep optical observations, two sources, High-z Lens 1 (HL1) West and HL1 East, are detected at the center of the three VLA/NOEMA blobs. These two sources are placed at z=1.48 with XSHOOTER spectra, suggesting that they could be merging and gravitationally lensing the emission of RV4. HL1 is the second most distant lens known to date in strong lensing systems. The Einstein radius of the lensing system is 2.2"+/-0.2 (20kpc). The high redshift of HL1 and the large Einstein radius are highly unusual for a strong lensing system. We present the ISM properties of the background source RV4. Different estimates of the gas depletion time yield low values suggesting that RV4 is a SB galaxy. Among all high-z SMGs, this source exhibits one of the lowest L$_{[CI]}$ to L$_{IR}$ ratios, 3.2+/-0.9x10$^{-6}$, suggesting an extremely short gas tdepl of only 14+/-5Myr. It also shows a relatively high L$_{[CI]}$ to L$_{CO(4-3)}$ ratio (0.7+/-0.2) and low L$_{CO(5-4)}$ to L$_{IR}$ ratio (only ~50% of the value expected for normal galaxies) hinting a low density of gas. Finally, we discuss that the short tdepl of RV4 can be explained by either a very high SFE, which is difficult to reconcile with major mergers simulations of high-z galaxies, or a rapid decrease of SF, which would bias the estimate of tdepl toward low value., Comment: 14 pages, 15 figures, accepted for publication in A&A

The first generation of stars were born a few hundred million years after the big bang. These stars synthesized elements heavier than H and He, that are later expelled into the interstellar medium, initiating the rise of metals. Within this enriched medium, the first dust grains formed. This event is cosmological crucial for molecule formation as dust plays a major role by cooling low-metallicity star-forming clouds which can fragment to create lower mass stars. Collecting information on these first dust grains is difficult because of the negative alliance of large distances and low dust masses. We combine the observational information from galaxies at redshifts 5 < z < 10 to constrain their dust emission and theoretically understand the first evolutionary phases of the dust cycle. Spectral energy distributions (SEDs) are fitted with CIGALE and the physical parameters and their evolution are modelled. From this SED fitting, we build a dust emission template for this population of galaxies in the epoch of reionization. Our new models explain why some early galaxies are observed and others are not. We follow in time the formation of the first grains by supernovae later destroyed by other supernova blasts and expelled in the circumgalactic and intergalactic media. We have found evidence for the first dust grains formed in the universe. But, above all, this letter underlines the need to collect more data and to develop new facilities to further constrain the dust cycle in galaxies in the epoch of reionization., Comment: Paper accepted for publication in section 4. Extragalactic astronomy of Astronomy and Astrophysics (Feb. 2020). Correction typo in caption of Fig. 1

arXiv:2011.09220v1, X-CIGALE is built on the spectral energy distribution (SED) code of CIGALE and implements important new features: the code accounts for obscuring material in the poles of AGNs and has the ability to fit X-ray fluxes. In this work, we used ∼2500 spectroscopic X-ray AGNs from the XMM-XXL-north field and examined the improvements the new features bring to the SED modelling analysis. Based on our results, X-CIGALE successfully connects the X-ray with the UV luminosity in the whole range spanned by our sample (log LX(2−10 keV) = (42−46) erg s−1). The addition of the new features generally improves the efficiency of X-CIGALE in the estimation and characterisation of the AGN component. Classification as type 1 or type 2 based on their inclination angle is improved, especially at redshifts lower than 1. The statistical significance of AGN fraction, fracAGN, measurements is increased, in particular for luminous X-ray sources (LX > 1045 erg s−1). These conclusions hold under the condition that (mid-) IR photometry is available in the SED fitting process. The addition of polar dust increases the AGN fraction and the efficiency of the SED decomposition to detect AGNs among X-ray selected sources. X-CIGALE estimates a strong AGN (fracAGN > 0.3) in more than 90% of the IR-selected AGNs and 75% of X-ray-detected AGNs not selected by IR colour criteria. The latter drops to ∼50% when polar dust is not included. The ability of X-CIGALE to include X-ray information in the SED fitting process can be instrumental in the optimal exploitation of the wealth of data that current (eROSITA) and future (ATHENA) missions will provide us., GM acknowledges support by the Agencia Estatal de Investigación, Unidad de Excelencia María de Maeztu, ref. MDM-2017-0765. MB acknowledges FONDECYT regular grant 1170618.

We estimated several parameters of dwarf galaxies, including their star formation rate and dust mass, and compared them with galaxies with larger stellar masses.We have chosen dwarf galaxies in the ELAIS N1 field, and fitted their Spectral Energy Distributions (SED). We used data from the new Herschel SPIRE and PACS Point Source catalogues to constrain the infrared radiation. Data available in VIZIER from multiple surveys have also been used.We determined that the star formation rate (SFR), M* and Mdust is one order of magnitude lower in dwarf galaxies compared to galaxies with larger stellar masses. However, the starburtiness was higher in the dwarf galaxies. They also had lower redshifts than normal galaxies, so we compared them to a subsample of normal galaxies with lower redshifts. The dust masses and SFRs of the dwarf galaxies were slightly lower, but their starburtiness was higher.

[Aims]: Dust is observed in the polar regions of nearby active galactic nuclei (AGN) and it is known to contribute substantially to their mid-IR emission and to the obscuration of their UV to optical emission. We aim to carry out a statistical test to check whether this component is a common feature based on an analysis of the integrated spectral energy distributions of these composite sources., [Methods]: We selected a sample of 1275 broad-line AGN in the XMM-XXL field, with optical to infrared photometric data. These AGN are seen along their polar direction and we expect a maximal impact of dust located around the poles when it is present. We used X-CIGALE, which introduces a dust component to account for obscuration along the polar directions, modeled as a foreground screen, and an extinction curve that is chosen as it steepens significantly at short wavelengths or is much grayer. By comparing the results of different fits, we are able to define subsamples of sources with positive statistical evidence in favor of or against polar obscuration (if present) and described using the gray or steep extinction curve., [Results]: We find a similar fraction of sources with positive evidence for and against polar dust. Applying statistical corrections, we estimate that half of our sample could contain polar dust and among them, 60% exhibit a steep extinction curve and 40% a flat extinction curve; although these latter percentages are found to depend on the adopted extinction curves. The obscuration in the V-band is not found to correlate with the X-ray column density, while AV/NH ratios span a large range of values and higher dust temperatures are found with the flat, rather than with the steep extinction curve. Ignoring this polar dust component in the fit of the spectral energy distribution of these composite systems leads to an overestimation of the stellar contribution. A single fit with a polar dust component described with an SMC extinction curve efficiently overcomes this issue but it fails at identifying all the AGN with polar dust obscuration., The project has received funding from Excellence Initiative of Aix-Marseille University – AMIDEX, a French ‘Investissements d’Avenir’ programme. GM acknowledges support by the Agencia Estatal de Investigacíon, Unidad de Excelencia María de Maeztu, ref. MDM-2017-0765. M.S. acknowledges support by the Ministry of Education, Science and Technological Development of the Republic of Serbia through the contract no. 451-03- 9/2021-14/200002 and by the Science Fund of the Republic of Serbia, PROMIS 6060916, BOWIE.

The preliminary data reduction, analysis and first results from the Herschel survey of the AKARI NEP field are presented. Herschel SPIRE observations of the NEP-Wide region and PACS observations of the NEP-Deep region have yielded galaxy catalogues of 4000 and 900 sources respectively down to flux density levels of approximately 15 mJy at 100-250 microns. Source counts produced from these catalogues reach cosmologically significant depths tracing the evolutionary upturn and turnover in the source counts. The source counts are in agreement with other large area surveys carried out with Herschel bridging the gap between the shallow and deep Herschel surveys.

CIGALE is a powerful multiwavelength spectral energy distribution (SED) fitting code for extragalactic studies. However, the current version of CIGALE is not able to fit X-ray data, which often provide unique insights into AGN intrinsic power. We develop a new X-ray module for CIGALE, allowing it to fit SEDs from the X-ray to infrared (IR). We also improve the AGN fitting of CIGALE from UV-to-IR wavelengths. We implement a modern clumpy two-phase torus model, SKIRTOR. To account for moderately extincted type 1 AGNs, we implement polar-dust extinction. We publicly release the source code (named "X-CIGALE"). We test X-CIGALE with X-ray detected AGNs in SDSS, COSMOS, and AKARI-NEP. The fitting quality (as indicated by reduced χ 2) is good in general, indicating that X-CIGALE is capable of modelling the observed SED from X-ray to IR. We discuss constrainability and degeneracy of model parameters in the fitting of AKARI-NEP, for which excellent mid-IR photometric coverage is available. We also test fitting a sample of AKARI-NEP galaxies for which only X-ray upper limits are available from Chandra observations, and find that the upper limit can effectively constrain the AGN SED contribution for some systems. Finally, using X-CIGALE, we assess the ability of Athena to constrain the AGN activity in future extragalactic studies., CIGALE est un code d'ajustement puissant pour la distribution d'énergie spectrale multi-longueur d'onde (SED) destiné aux études extragalactiques. Cependant, la version actuelle de CIGALE n’est pas en mesure d’adapter les données de rayons X, qui fournissent souvent des informations uniques sur la puissance intrinsèque d’AGN. Nous développons un nouveau module de rayons X pour CIGALE, lui permettant de modéliser les SED des rayons X à l’infrarouge (IR). Nous améliorons également l'ajustement AGN de ​​CIGALE des longueurs d'onde UV à IR. Nous utilisons un modèle de tore à deux phases : SKIRTOR. Pour prendre en compte les AGN de ​​type 1 moyennement éteints, nous mettons en œuvre l'extinction des poussières polaires. Nous publions publiquement le code source (nommé "X-CIGALE"). Nous testons X-CIGALE avec des AGN détectés par rayons X dans SDSS, COSMOS et AKARI-NEP. La qualité d'ajustement (indiquée par la réduction de χ 2) est généralement bonne, ce qui indique que X-CIGALE est capable de modéliser le SED observé des rayons X à l'infrarouge. Nous discutons de la constrainabilité et de la dégénérescence des paramètres du modèle lors de l'ajustement d'AKARI-NEP, pour lequel une excellente couverture photométrique en IR moyen est disponible. Nous testons également l'ajustement d'un échantillon de galaxies AKARI-NEP pour lesquelles seules les limites supérieures aux rayons X sont disponibles à partir des observations de Chandra, et nous constatons que la limite supérieure peut effectivement limiter la contribution du SED d'AGN pour certains systèmes. Enfin, à l’aide de X-CIGALE, nous évaluons la capacité d’Athéna à limiter l’activité d’AGN dans de futures études extragalactiques.