scholarly journals SMM J04135+10277: a distant QSO–starburst system caught by ALMA

2020 ◽  
Vol 493 (3) ◽  
pp. 3744-3756 ◽  
Author(s):  
Judit Fogasy ◽  
K K Knudsen ◽  
G Drouart ◽  
C D P Lagos ◽  
L Fan
Keyword(s):  
Star Formation ◽  
Galaxy Evolution ◽  
Spectral Energy Distribution ◽  
Line Emission ◽  
Continuum Emission ◽  
Host Galaxy ◽  
Spectral Energy ◽  
Molecular Gas ◽  
Gas Reservoir ◽  
Companion Galaxy

ABSTRACT The gas content of galaxies is a key factor for their growth, starting from star formation and black hole accretion to galaxy mergers. Thus, characterizing its properties through observations of tracers like the CO emission line is of big importance in order to understand the bigger picture of galaxy evolution. We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of dust continuum, CO(5–4) and CO(8–7) line emission in the quasar–star-forming companion system SMM J04135+10277 (z = 2.84). Earlier low-J CO studies of this system found a huge molecular gas reservoir associated with the companion galaxy, while the quasar appeared gas-poor. Our CO observations revealed that the host galaxy of the quasar is also gas-rich, with an estimated molecular gas mass of $\sim (0.7{\!-\!}2.3)\times 10^{10}\, \rm M_{\odot}$. The CO line profiles of the companion galaxy are very broad ($\sim 1000\, \rm km\, s^{-1}$), and show signs of rotation of a compact, massive system. In contrast to previous far-infrared observations, we resolve the continuum emission and detect both sources, with the companion galaxy dominating the dust continuum and the quasar having a $\sim 25{{\ \rm per\ cent}}$ contribution to the total dust emission. By fitting the infrared spectral energy distribution of the sources with mr-moose and empirical templates, the infrared luminosities of the quasar and the companion are in the range of $L_{\rm IR, QSO}\sim (2.1{\!-\!}9.6)\times 10^{12}\, \rm L_{\odot}$ and $L_{\rm IR, Comp.}\sim (2.4{\!-\!}24)\times 10^{12}\, \rm L_{\odot}$, while the estimated star formation rates are $\sim 210{\!-\!}960$ and $\sim 240{\!-\!}2400\, \rm M_{\odot }\, yr^{-1}$, respectively. Our results demonstrate that non-detection of low-J CO transition lines in similar sources does not necessarily imply the absence of massive molecular gas reservoir but that the excitation conditions favour the excitation of high-J transitions.

scholarly journals ALMA view of RX J1131-1231: Sub-kpc CO (2-1) mapping of a molecular disk in a lensed star-forming quasar host galaxy

2018 ◽  
Vol 613 ◽  
pp. A34 ◽  
Author(s):  
D. Paraficz ◽  
M. Rybak ◽  
J. P. McKean ◽  
S. Vegetti ◽  
D. Sluse ◽  
...  
Keyword(s):  
Star Formation ◽  
Rotational Velocity ◽  
Spectral Energy Distribution ◽  
Optical Emission ◽  
Continuum Emission ◽  
Host Galaxy ◽  
Spectral Energy ◽  
Molecular Gas ◽  
Gas Velocity ◽  
Star Forming

We present ALMA 2-mm continuum and CO (2-1) spectral line imaging of the gravitationally lensed z = 0.654 star-forming/quasar composite RX J1131-1231 at 240–400 mas angular resolution. The continuum emission is found to be compact and coincident with the optical emission, whereas the molecular gas forms a complete Einstein ring, which shows strong differential magnification. The de-lensed source structure is determined on 400-parsec-scales resolution using a Bayesian pixelated visibility-fitting lens modelling technique. The reconstructed molecular gas velocity-field is consistent with a large rotating disk with a major-axis FWHM ~9.4 kpc at an inclination angle of i = 54° and with a maximum rotational velocity of 280 km s−1. From dynamical model fitting we find an enclosed mass within 5 kpc of M(r < 5 kpc) = (1.46 ± 0.31) × 1011 M⊙. The molecular gas distribution is highly structured, with clumps that are co-incident with higher gas velocity dispersion regions (40–50 km s−1) and with the intensity peaks in the optical emission, which are associated with sites of on-going turbulent star-formation. The peak in the CO (2-1) distribution is not co-incident with the AGN, where there is a paucity of molecular gas emission, possibly due to radiative feedback from the central engine. The intrinsic molecular gas luminosity is L′CO = 1.2 ± 0.3 × 1010 K km s−1 pc2 and the inferred gas mass is MH2 = 8.3 ± 3.0 × 1010 M⊙, which given the dynamical mass of the system is consistent with a CO–H2 conversion factor of α = 5.5 ± 2.0 M⊙ (K km s−1 pc2)−1. This suggests that the star-formation efficiency is dependent on the host galaxy morphology as opposed to the nature of the AGN. The far-infrared continuum spectral energy distribution shows evidence for heated dust, equivalent to an obscured star-formation rate of SFR = 69−25+41 × (7.3/μIR) M⊙ yr−1, which demonstrates the composite star-forming and AGN nature of this system.

scholarly journals Self-consistent population spectral synthesis with FADO

2019 ◽  
Vol 622 ◽  
pp. A56 ◽  
Author(s):  
Leandro S. M. Cardoso ◽  
Jean Michel Gomes ◽  
Polychronis Papaderos
Keyword(s):  
Star Formation ◽  
Galaxy Evolution ◽  
Spectral Synthesis ◽  
Spectral Energy Distribution ◽  
Formation Rate ◽  
Continuum Emission ◽  
Spectral Energy ◽  
Spectral Evolution ◽  
Fitting Procedure ◽  
Self Consistent

Context. Spectral population synthesis (PS) is a fundamental tool in extragalactic research that aims to decipher the assembly history of galaxies from their spectral energy distribution (SED). Whereas this technique has led to key insights into galaxy evolution in recent decades, star formation histories (SFHs) inferred therefrom have been plagued by considerable uncertainties stemming from inherent degeneracies and the fact that until recently all PS codes were restricted to purely stellar fits, neglecting the essential contribution of nebular emission (ne). With the advent of FADO (Fitting Analysis using Differential evolution Optimisation), the now possible self-consistent modelling of stellar and ne opens new routes to the exploration of galaxy SFHs. Aims. The main goal of this study is to quantitatively explore the accuracy to which FADO can recover physical and evolutionary properties of galaxies and compare its output with that from purely stellar PS codes. Methods. FADO and STARLIGHT were applied to synthetic SEDs that track the spectral evolution of stars and gas in extinction-free mock galaxies of solar metallicity that form their stellar mass (M⋆) according to different parametric SFHs. Spectral fits were computed for two different set-ups that approximate the spectral range of SDSS and CALIFA (V500) data, using up to seven libraries of simple stellar population spectra in the 0.005–2.5 Z⊙ metallicity range. Results. Our analysis indicates that FADO can recover the key physical and evolutionary properties of galaxies, such as M⋆ and mass- and light-weighted mean age and metallicity, with an accuracy better than 0.2 dex. This is the case even in phases of strongly elevated specific star formation rate (sSFR) and thus with considerable ne contamination (EW(Hα) >  103 Å). Likewise, population vectors from FADO adequately recover the mass fraction of stars younger than 10 Myr and older than 1 Gyr (M⋆<10Myr/M⋆total and M⋆>1Gyr/M⋆total, respectively) and reproduce with a high fidelity the observed Hα luminosity. As for STARLIGHT, our analysis documents a moderately good agreement with theoretical values only for evolutionary phases for which ne drops to low levels (EW(Hα) ≤ 60 Å) which, depending on the assumed SFH, correspond to an age between ∼0.1 Gyr and 2–4 Gyr. However, fits with STARLIGHT during phases of high sSFR severely overestimate both M⋆ and the mass-weighted stellar age, whereas strongly underestimate the light-weighted age and metallicity. Furthermore, our analysis suggests a subtle tendency of STARLIGHT to favour a bi-modal SFH, as well a slightly overestimated M⋆<10Myr/M⋆total, regardless of galaxy age. Whereas the amplitude of these biases can be reduced, depending on the specifics of the fitting procedure (e.g. accuracy and completeness of flagging emission lines, omission of the Balmer and Paschen jump from the fit), they persist even in the idealised case of a line-free SED comprising only stellar and nebular continuum emission. Conclusions. The insights from this study suggest that the neglect of nebular continuum emission in STARLIGHT and similar purely stellar PS codes could systematically impact M⋆ and SFH estimates for star-forming galaxies. We argue that these biases can be relevant in the study of a range of topics in extragalactic research, including the redshift-dependent slope of the star formation (SF) main sequence, the SF frosting hypothesis, and the regulatory role of supermassive black holes on the global SFH of galaxies.

scholarly journals Star formation and gas in the minor merger UGC 10214

2019 ◽  
Vol 623 ◽  
pp. A154
Author(s):  
D. Rosado-Belza ◽  
U. Lisenfeld ◽  
J. Hibbard ◽  
K. Kniermann ◽  
J. Ott ◽  
...  
Keyword(s):  
Star Formation ◽  
Galaxy Evolution ◽  
Spectral Energy Distribution ◽  
Stellar Mass ◽  
High Mass ◽  
Spectral Energy ◽  
Molecular Gas ◽  
Moderate Increase ◽  
The Past ◽  
The Galaxy

Minor mergers play a crucial role in galaxy evolution. UGC 10214 (the Tadpole galaxy) is a prime example of this process in which a dwarf galaxy has interacted with a large spiral galaxy ∼250 Myr ago and produced a perturbed disc and a giant tidal tail. We used a multi-wavelength dataset that partly consists of new observations (Hα, HI, and CO) and partly of archival data to study the present and past star formation rate (SFR) and its relation to the gas and stellar mass at a spatial resolution down to 4 kpc. UGC 10214 is a high-mass (stellar mass M⋆ = 1.28 × 1011 M⊙) galaxy with a low gas fraction (Mgas/M⋆ = 0.24), a high molecular gas fraction (MH2/MHI = 0.4), and a modest SFR (2–5 M⊙ yr−1). The global SFR compared to its stellar mass places UGC 10214 on the galaxy main sequence (MS). The comparison of the molecular gas mass and current SFR gives a molecular gas depletion time of about ∼2 Gyr (based on Hα), comparable to those of normal spiral galaxies. Both from a comparison of the Hα emission, tracing the current SFR, and far-ultraviolet (FUV) emission, tracing the recent SFR during the past tens of Myr, and also from spectral energy distribution fitting with CIGALE, we find that the SFR has increased by a factor of about 2–3 during the recent past. This increase is particularly noticeable in the centre of the galaxy where a pronounced peak of the Hα emission is visible. A pixel-to-pixel comparison of the SFR, molecular gas mass, and stellar mass shows that the central region has had a depressed FUV-traced SFR compared to the molecular gas and the stellar mass, whereas the Hα-traced SFR shows a normal level. The atomic and molecular gas distribution is asymmetric, but the position-velocity diagram along the major axis shows a pattern of regular rotation. We conclude that the minor merger has most likely caused variations in the SFR in the past that resulted in a moderate increase of the SFR, but it has not perturbed the gas significantly so that the molecular depletion time remains normal.

scholarly journals The star formation properties of the observed and simulated AGN Universe: BAT versus EAGLE

2020 ◽  
Vol 498 (2) ◽  
pp. 2323-2338
Author(s):  
Thomas M Jackson ◽  
D J Rosario ◽  
D M Alexander ◽  
J Scholtz ◽  
Stuart McAlpine ◽  
...  
Keyword(s):  
Star Formation ◽  
High Redshift ◽  
Spectral Energy Distribution ◽  
Formation Rate ◽  
Host Galaxy ◽  
Spectral Energy ◽  
Host Galaxies ◽  
X Ray ◽  
Two Samples ◽  
Stellar Masses

ABSTRACT In this paper, we present data from 72 low-redshift, hard X-ray selected active galactic nucleus (AGN) taken from the Swift–BAT 58 month catalogue. We utilize spectral energy distribution fitting to the optical to infrared photometry in order to estimate host galaxy properties. We compare this observational sample to a volume- and flux-matched sample of AGN from the Evolution and Assembly of GaLaxies and their Environments (EAGLE) hydrodynamical simulations in order to verify how accurately the simulations can reproduce observed AGN host galaxy properties. After correcting for the known +0.2 dex offset in the SFRs between EAGLE and previous observations, we find agreement in the star formation rate (SFR) and X-ray luminosity distributions; however, we find that the stellar masses in EAGLE are 0.2–0.4 dex greater than the observational sample, which consequently leads to lower specific star formation rates (sSFRs). We compare these results to our previous study at high redshift, finding agreement in both the observations and simulations, whereby the widths of sSFR distributions are similar (∼0.4–0.6 dex) and the median of the SFR distributions lie below the star-forming main sequence by ∼0.3–0.5 dex across all samples. We also use EAGLE to select a sample of AGN host galaxies at high and low redshift and follow their characteristic evolution from z = 8 to z = 0. We find similar behaviour between these two samples, whereby star formation is quenched when the black hole goes through its phase of most rapid growth. Utilizing EAGLE we find that 23 per cent of AGN selected at z ∼ 0 are also AGN at high redshift, and that their host galaxies are among the most massive objects in the simulation. Overall, we find EAGLE reproduces the observations well, with some minor inconsistencies (∼0.2 dex in stellar masses and ∼0.4 dex in sSFRs).

scholarly journals An ASKAP survey for H i absorption towards dust-obscured quasars

2019 ◽  
Vol 489 (4) ◽  
pp. 4926-4943 ◽  
Author(s):  
M Glowacki ◽  
J R Allison ◽  
V A Moss ◽  
E K Mahony ◽  
E M Sadler ◽  
...  
Keyword(s):  
Galaxy Evolution ◽  
Spectral Energy Distribution ◽  
Galactic Nuclei ◽  
Host Galaxy ◽  
Spectral Energy ◽  
Neutral Medium ◽  
Host Galaxies ◽  
Gas Kinematics ◽  
Neutral Gas

ABSTRACT Obscuration of quasars by accreted gas and dust, or dusty intervening galaxies, can cause active galactic nuclei (AGN) to be missed in optically selected surveys. Radio observations can overcome this dust bias. In particular, radio surveys searching for H i absorption inform us on how the AGN can impact on the cold neutral gas medium within the host galaxy, or the population of intervening galaxies through the observed line of sight gas kinematics. We present the results of an H i absorption line survey at 0.4 &lt; z &lt; 1 towards 34 obscured quasars with the Australian SKA Pathfinder (ASKAP) commissioning array. We detect three H i absorption lines, with one of these systems previously unknown. Through optical follow-up for two sources, we find that in all detections the H i gas is associated with the AGN, and hence that these AGN are obscured by material within their host galaxies. Most of our sample are compact, and in addition, are either gigahertz peaked spectrum (GPS), or steep spectrum (CSS) sources, both thought to represent young or recently re-triggered radio AGN. The radio spectral energy distribution classifications for our sample agree with galaxy evolution models in which the obscured AGN has only recently become active. Our associated H i detection rate for GPS and compact SS sources matches those of other surveys towards such sources. We also find shallow and asymmetric H i absorption features, which agrees with previous findings that the cold neutral medium in compact radio galaxies is typically kinematically disturbed by the AGN.

scholarly journals SUPER

2018 ◽  
Vol 620 ◽  
pp. A82 ◽  
Author(s):  
C. Circosta ◽  
V. Mainieri ◽  
P. Padovani ◽  
G. Lanzuisi ◽  
M. Salvato ◽  
...  
Keyword(s):  
Star Formation ◽  
Adaptive Optics ◽  
High Redshift ◽  
Spectral Energy Distribution ◽  
Host Galaxy ◽  
Spectral Energy ◽  
Distribution Fitting ◽  
X Ray ◽  
Narrow Component ◽  
The Impact

Theoretical models of galaxy formation suggest that the presence of an active galactic nucleus (AGN) is required to regulate the growth of its host galaxy through feedback mechanisms, produced by, for example, AGN-driven outflows. Although many observational studies have revealed that such outflows are common both at low and high redshift, a comprehensive picture is still missing. In particular, the peak epoch of galaxy assembly (1 <  z <  3) has been poorly explored so far, and current observations in this redshift range are mostly limited to targets with high chances to be in an outflowing phase. This paper introduces SUPER (a SINFONI Survey for Unveiling the Physics and Effect of Radiative feedback), an ongoing ESO’s VLT/SINFONI Large Programme. SUPER will perform the first systematic investigation of ionized outflows in a sizeable and blindly-selected sample of 39 X-ray AGN at z ∼ 2, which reaches high spatial resolutions (∼2 kpc) thanks to the adaptive optics-assisted IFS observations. The outflow morphology and star formation in the host galaxy will be mapped through the broad component of [O III]λ5007 and the narrow component of Hα emission lines. The main aim of our survey is to infer the impact of outflows on the on-going star formation and to link the outflow properties to a number of AGN and host galaxy properties. We describe here the survey characteristics and goals, as well as the selection of the target sample. Moreover, we present a full characterization of its multi-wavelength properties: we measure, via spectral energy distribution fitting of UV-to-FIR photometry, stellar masses (4 × 109 − 2 × 1011 M⊙), star formation rates (25 − 680 M⊙ yr−1) and AGN bolometric luminosities (2 × 1044 − 8 × 1047 erg s−1), along with obscuring column densities (up to 2 × 1024 cm−2) and luminosities in the hard 2 − 10 keV band (2 × 1043 − 6 × 1045 erg s−1) derived through X-ray spectral analysis. Finally, we classify our AGN as jetted or non-jetted according to their radio and FIR emission.

scholarly journals The ‘Red Radio Ring’: ionized and molecular gas in a starburst/active galactic nucleus at z ∼ 2.55

2019 ◽  
Vol 488 (2) ◽  
pp. 1489-1500 ◽  
Author(s):  
Kevin C Harrington ◽  
A Vishwas ◽  
A Weiß ◽  
B Magnelli ◽  
L Grassitelli ◽  
...  
Keyword(s):  
Fine Structure ◽  
Spectral Energy Distribution ◽  
Formation Rate ◽  
Line Emission ◽  
Far Infrared ◽  
Spectral Energy ◽  
Molecular Gas ◽  
H Ii Regions ◽  
Galaxy Assembly ◽  
Dust Attenuation

ABSTRACT We report the detection of the far-infrared (FIR) fine-structure line of singly ionized nitrogen, [N ii] 205 $\mu$m , within the peak epoch of galaxy assembly, from a strongly lensed galaxy, hereafter ‘The Red Radio Ring’; the RRR, at z = 2.55. We combine new observations of the ground-state and mid-J transitions of CO (Jup = 1, 5, 8), and the FIR spectral energy distribution (SED), to explore the multiphase interstellar medium (ISM) properties of the RRR. All line profiles suggest that the H ii regions, traced by [N ii] 205 $\mu$m , and the (diffuse and dense) molecular gas, traced by CO, are cospatial when averaged over kpc-sized regions. Using its mid-IR-to-millimetre (mm) SED, we derive a non-negligible dust attenuation of the [N ii] 205 $\mu$m line emission. Assuming a uniform dust screen approximation results a mean molecular gas column density &gt;1024 cm−2, with a molecular gas-to-dust mass ratio of 100. It is clear that dust attenuation corrections should be accounted for when studying FIR fine-structure lines in such systems. The attenuation corrected ratio of $L_{\rm N\,{\small II}205} / L_{\rm IR(8\!-\!1000\, \mu m)} = 2.7 \times 10^{-4}$ is consistent with the dispersion of local and z &gt; 4 SFGs. We find that the lower limit, [N ii] 205 $\mu$m -based star formation rate (SFR) is less than the IR-derived SFR by a factor of 4. Finally, the dust SED, CO line SED, and $L_{\rm N\,{\small II}205}$ line-to-IR luminosity ratio of the RRR is consistent with a starburst-powered ISM.

scholarly journals Mentari: A pipeline to model the galaxy SED using semi analytic models

2019 ◽  
Vol 15 (S341) ◽  
pp. 119-123
Author(s):  
Dian Triani ◽  
Darren Croton ◽  
Manodeep Sinha
Keyword(s):  
Star Formation ◽  
Galaxy Evolution ◽  
Spectral Energy Distribution ◽  
Cosmic Time ◽  
Spectral Energy ◽  
Chemical Enrichment ◽  
The Galaxy ◽  
History Of ◽  
Gas Accretion ◽  
Analytic Models

AbstractWe build a theoretical picture of how the light from galaxies evolves across cosmic time. In particular, we predict the evolution of the galaxy spectral energy distribution (SED) by carefully integrating the star formation and metal enrichment histories of semi-analytic model (SAM) galaxies and combining these with stellar population synthesis models which we call mentari. Our SAM combines prescriptions to model the interplay between gas accretion, star formation, feedback process, and chemical enrichment in galaxy evolution. From this, the SED of any simulated galaxy at any point in its history can be constructed and compared with telescope data to reverse engineer the various physical processes that may have led to a particular set of observations. The synthetic SEDs of millions of simulated galaxies from mentari can cover wavelengths from the far UV to infrared, and thus can tell a near complete story of the history of galaxy evolution.

scholarly journals Fraction of bolometric luminosity absorbed by dust in DustPedia galaxies

2018 ◽  
Vol 620 ◽  
pp. A112 ◽  
Author(s):  
S. Bianchi ◽  
P. De Vis ◽  
S. Viaene ◽  
A. Nersesian ◽  
A. V. Mosenkov ◽  
...  
Keyword(s):  
Star Formation ◽  
Galaxy Evolution ◽  
Star Formation Rate ◽  
Spectral Energy Distribution ◽  
Formation Rate ◽  
Spectral Energy ◽  
Stellar Content ◽  
Late Type ◽  
Bolometric Luminosity ◽  
Stellar Radiation

Aims. We aim to study the fraction of stellar radiation absorbed by dust, fabs, in 814 galaxies of different morphological types. The targets constitute the vast majority (93%) of the DustPedia sample, including almost all large (optical diameter larger than 1′), nearby (v ≤ 3000 km s−1) galaxies observed with the Herschel Space Observatory. Methods. For each object, we modelled the spectral energy distribution from the ultraviolet to the sub-millimetre using the dedicated, aperture-matched DustPedia photometry and the Code Investigating GALaxy Evolution (CIGALE). The value of fabs was obtained from the total luminosity emitted by dust and from the bolometric luminosity, which are estimated by the fit. Results. On average, 19% of the stellar radiation is absorbed by dust in DustPedia galaxies. The fraction rises to 25% if only late-type galaxies are considered. The dependence of fabs on morphology, showing a peak for Sb-Sc galaxies, is weak; it reflects a stronger, yet broad, positive correlation with the bolometric luminosity, which is identified for late-type, disk-dominated, high-specific-star-formation rate, gas-rich objects. We find no variation of fabs with inclination, at odds with radiative transfer models of edge-on galaxies. These results call for a self-consistent modelling of the evolution of the dust mass and geometry along the build-up of the stellar content. We also provide template spectral energy distributions in bins of morphology and luminosity and study the variation of fabs with stellar mass and specific star-formation rate. We confirm that the local Universe is missing the high fabs, luminous and actively star-forming objects necessary to explain the energy budget in observations of the extragalactic background light.

scholarly journals Disentangling the AGN and star formation connection using XMM-Newton

2018 ◽  
Vol 618 ◽  
pp. A31 ◽  
Author(s):  
V. A. Masoura ◽  
G. Mountrichas ◽  
I. Georgantopoulos ◽  
A. Ruiz ◽  
G. Magdis ◽  
...  
Keyword(s):  
Star Formation ◽  
Main Sequence ◽  
Learning Algorithm ◽  
Spectral Energy Distribution ◽  
Stellar Mass ◽  
Host Galaxy ◽  
Spectral Energy ◽  
X Ray ◽  
The Galaxy ◽  
Ir Photometry

There is growing evidence supporting the coeval growth of galaxies and their resident super-massive black hole (SMBH). Most studies also claim a correlation between the activity of the SMBH and the star formation of the host galaxy. It is unclear, however, whether this correlation extends to all redshifts and X-ray luminosities. Some studies find a weaker dependence at lower luminosities and/or a suppression of the star formation at high luminosities. We here use data from the X-ATLAS and XMM-XXL North fields and compile the largest X-ray sample up to date to investigate how X-ray selected AGN affect the star formation of their host galaxies in a wide redshift and luminosity baseline of 0.03 < z < 3 and log LX(2−10 keV) = (41−45.5) erg s−1. Our sample consists of 3336 AGN. 1872 of our sources have spectroscopic redshifts. For the remaining sources we calculate photometric redshifts using TPZ, a machine-learning algorithm. We estimate stellar masses (M⋆) and star formation rates (SFRs) by applying spectral energy distribution fitting through the CIGALE code, using optical, near-IR, and mid-IR photometry (SDSS, VISTA, and WISE). Of our sources, 608 also have far-IR photometry (Herschel). We use these sources to calibrate the SFR calculations of our remaining X-ray sample. Our results show a correlation between the X-ray luminosity (LX) and the SFR of the host galaxy at all redshifts and luminosities spanned by our sample. We also find a dependence of the specific SFR (sSFR) on redshift, while there are indications that the X-ray luminosity enhances the sSFR even at low redshifts. We then disentangle the effects of stellar mass and redshift on the SFR and again study its dependence on the X-ray luminosity. Towards this end, we estimate the SFR of main-sequence galaxies that have the same stellar mass and redshift as our X-ray AGN and compare them with the SFR of our X-ray AGN. Our analysis reveals that the AGN enhances the star formation of its host galaxy when the galaxy lies below the main sequence and quenches the star formation of the galaxy it lives in when the host lies above the main sequence. Therefore, the effect of AGN on the SFR of the host galaxy depends on the location of the galaxy relative to the main sequence.

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