Investigating the Effect of Galaxy Interactions on the Enhancement of Active Galactic Nuclei at 0.5 &lt; z &lt; 3.0

Shah, Ekta A.; Kartaltepe, Jeyhan S.; Magagnoli, Christina T.; Cox, Isabella G.; Wetherell, Caleb T.; Vanderhoof, Brittany N.; Calabró, Antonello; Chartab, Nima; Conselice, Christopher J.; Croton, Darren J.; Donley, J. L.; Groot, Laura de; Vega, Alexander de la; Hathi, N. P.; Ilbert, O.; Inami, Hanae; Kocevski, Dale D.; Koekemoer, Anton M.; Lemaux, Brian C.; Mantha, Kameswara Bharadwaj; Marchesi, S.; Martig, Marie; Masters, D. C.; McGrath, Elizabeth J.; McIntosh, Daniel H.; Moreno, Jorge; Nayyeri, Hooshang; Pampliega, B. Alcalde; Salvato, M.; Snyder, Gregory F.; Straughn, Amber N.; Treister, Ezequiel; Weston, Madalyn E.

doi:10.3847/1538-4357/abbf59

Cited by 45 publications

(45 citation statements)

References 199 publications

(368 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The interaction might also have triggered gas accretion on the supermassive black hole (SMBH) and a hidden AGN detected in radio. This is compatible with the discussion in Shah et al (2020) regarding the possibility of low-level AGN enhancement in galaxy interactions. Using BPT diagrams, we find that the two galaxies are located in different regions, associated with different states of ionisation.…”

Section: Possible Outflows Driven By Central Activitysupporting

confidence: 92%

See 1 more Smart Citation

Two interacting galaxies hiding as one, revealed by MaNGA

Ciraulo

Melchior

Maschmann

et al. 2021

A&A

View full text Add to dashboard Cite

Given their prominent role in galaxy evolution, it is of paramount importance to unveil galaxy interactions and merger events and to investigate the underlying mechanisms. The use of high-resolution data makes it easier to identify merging systems, but it can still be challenging when the morphology does not show any clear galaxy pair or gas bridge. Characterising the origin of puzzling kinematic features can help reveal complicated systems. Here, we present a merging galaxy, MaNGA 1-114955, in which we highlighted the superimposition of two distinct rotating discs along the line of sight. These counter-rotating objects both lie on the star-forming main sequence but display perturbed stellar velocity dispersions. The main galaxy presents off-centred star formation as well as off-centred high-metallicity regions, supporting the scenario of recent starbursts, while the secondary galaxy hosts a central starburst that coincides with an extended radio emission, in excess with respect to star formation expectations. Stellar mass as well as dynamical mass estimates agree towards a mass ratio within the visible radius of 9:1 for these interacting galaxies. We suggest that we are observing a pre-coalescence stage of a merger. The primary galaxy accreted gas through a past first pericentre passage about 1 Gyr ago and more recently from the secondary gas-rich galaxy, which exhibits an underlying active galactic nucleus. Our results demonstrate how a galaxy can hide another one and the relevance of a multi-component approach for studying ambiguous systems. We anticipate that our method will be efficient at unveiling the mechanisms taking place in a sub-sample of galaxies observed by the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, all of which exhibit kinematic features of a puzzling origin in their gas emission lines.

show abstract

Section: Possible Outflows Driven By Central Activitysupporting

confidence: 92%

“…Lastly, some important questions remain unanswered regarding the possible impact of AGNs on the merging stage (e.g. Alonso et al 2007;McAlpine et al 2020;Shah et al 2020;Sharma et al 2021) and whether the quenching is related to the merging (e.g. Ellison et al 2018;Hani et al 2020;Das et al 2021).…”

Section: Introductionmentioning

confidence: 99%

Two interacting galaxies hiding as one, revealed by MaNGA

Ciraulo

Melchior

Maschmann

et al. 2021

A&A

View full text Add to dashboard Cite

show abstract

“…This evidence could suggest that merging events have happened in these RAGNs/Type 1 AGN, which have served to boost their stellar mass and lower their local density at the same time retaining their global environment. In addition, mergers are sometimes thought to be responsible for transporting available gas on host galaxy scales to the central regions, triggering activity in the nucleus (e.g., Ellison et al 2011;Chiaberge et al 2015;Padovani 2016;Tadhunter 2016, though see, e.g., Kocevski et al 2012Shah et al 2020 for an alternative view).…”

Section: The Formation and Evolution Of Ragnsmentioning

confidence: 99%

Implications of the Environments of Radio-detected Active Galactic Nuclei in a Complex Protostructure at z ∼ 3.3

Shen

Lemaux

Lubin

et al. 2021

ApJ

Self Cite

View full text Add to dashboard Cite

Radio active galactic nuclei (RAGNs) are mainly found in dense structures (i.e., clusters/groups) at redshifts of z < 2 and are commonly used to detect protoclusters at higher redshift. Here, we attempt to study the host and environmental properties of two relatively faint (L 1.4 GHz ∼ 1025 W Hz−1) RAGNs in a known protocluster at z = 3.3 in the PCl J0227-0421 field, detected using the latest radio observation obtained as part of the Observations of Redshift Evolution in Large-Scale Environments (ORELSE) survey. Using new spectroscopic observations obtained from the Keck/Multi-Object Spectrometer for Infra-Red Exploration as part of the Charting Cluster Construction with the VIMOS Ultra-Deep Survey (VUDS) and ORELSE (C3VO) survey and previous spectroscopic data obtained as part of the VIMOS-Very Large Telescope Deep Survey and VUDS, we revise the three-dimensional overdensity field around this protocluster. The protocluster is embedded in a large-scale overdensity protostructure. This protostructure has an estimated total mass of ∼2.6 × 1015 M ⊙ and contains several overdensity peaks. Both RAGNs are hosted by very bright and massive galaxies, while their hosts show extreme differences in color, indicating that they are of different ages and are in different evolutionary stages. Furthermore, we find that they are not in the most locally dense parts of the protostructure, but are fairly close to the centers of their parent overdensity peaks. We propose a scenario where merging might have already happened in both cases, which lowered the local density of their surrounding area and boosted their stellar mass. This work is the first time that two RAGNs at low luminosity have been found and studied within a high-redshift protostructure.

show abstract

“…The merging of galaxies is a natural prediction of the hierarchical structure formation model (White & Frenk 1991;Springel et al 2005;Klypin et al 2011) for which dark matter halos grow their mass and affect the build-up of galaxies in the Universe (Kauffmann et al 1993;Khochfar & Burkert 2005). Not only can mergers increase the stellar mass of galaxies (up to a factor of 2 for major mergers, i.e., for galaxies of nearly equal stellar mass; López-Sanjuan et al 2012;Oser et al 2012;Kaviraj et al 2014), but they can also trigger starbursts and active galactic nuclei (AGN; Silk & Rees 1998;Kartaltepe et al 2012;Chiaberge et al 2015; see also Shah et al 2020 who found that galaxy interactions do not significantly enhance AGN activity up to z ∼ 3), in some cases blowing the gas out from the galaxy which arrests, at least temporarily, the formation of new stars (Silk & Rees 1998;Fabian et al 2006;Cattaneo et al 2009). Therefore, observing mergers at different epochs is key to shed light on the relative contribution of the distinct processes that rule the assembly of galaxies in the Universe.…”

Section: Introductionmentioning

confidence: 99%

The ALPINE-ALMA [CII] survey

Romano

Cassata

Morselli

et al. 2021

A&A

View full text Add to dashboard Cite

Context. Galaxy mergers are thought to be one of the main mechanisms of the mass assembly of galaxies in the Universe, but there is still little direct observational evidence of how frequent they are at z ≳ 4. Recently, many works have suggested a possible increase in the fraction of major mergers in the early Universe, reviving the debate on which processes (e.g., cold accretion, star formation, mergers) most contribute to the mass build-up of galaxies through cosmic time. Aims. To estimate the importance of major mergers in this context, we make use of the new data collected by the ALMA Large Program to INvestigate [CII] at Early times (ALPINE) survey, which attempted to observe the [CII] 158 μm emission line from a sample of 75 main-sequence star-forming galaxies at 4.4 < z < 5.9. Methods. We used, for the first time, the morpho-kinematic information provided by the [CII] emission, along with archival multiwavelength data to obtain the fraction of major mergers (fMM) at z ∼ 5. By combining the results from ALPINE with those at lower redshifts from the literature, we also studied the evolution of the merger fraction through cosmic time. We then used different redshift-evolving merger timescales (TMM) to convert this fraction into the merger rate per galaxy (RMM) and in the volume-averaged merger rate (ΓMM). Results. We find a merger fraction of fMM ∼ 0.44 (0.34) at z ∼ 4.5 (5.5) from ALPINE. By combining our results with those at lower redshifts, we computed the cosmic evolution of the merger fraction which is described by a rapid increase from the local Universe to higher redshifts, a peak at z ∼ 3, and a slow decrease toward earlier epochs. Depending on the timescale prescription used, this fraction translates into a merger rate ranging between ∼0.1 and ∼4.0 Gyr−1 at z ∼ 5, which in turn corresponds to an average number of major mergers per galaxy between 1 and 8 in ∼12.5 yr (from z = 6 to the local Universe). When convolved with the galaxy number density at different epochs, the merger rate density becomes approximately constant over time at 1 < z < 4, including values from 10−4 to 10−3 Gyr−1 Mpc−3, depending on the assumed TMM. We finally compare the specific star formation and star-formation rate density with the analogous quantities from major mergers, finding a good agreement at z > 4 if we assume a merger timescale that quickly decreases with increasing redshift. Conclusions. Our new constraints on the merger fraction from the ALPINE survey at z ∼ 5 reveal the presence of a significant merging activity in the early Universe. Whether this population of mergers can provide a relevant contribution to the galaxy mass assembly at these redshifts and through the cosmic epochs is strongly dependent on the assumption of the merger timescale. However, our results show that an evolving TMM ∝ (1 + z)−2 agrees well with state-of-the-art cosmological simulations, suggesting a considerable role of mergers in the build-up of galaxies at early times.

show abstract

Investigating the Effect of Galaxy Interactions on the Enhancement of Active Galactic Nuclei at 0.5 < z < 3.0

Cited by 45 publications

References 199 publications

Two interacting galaxies hiding as one, revealed by MaNGA

Two interacting galaxies hiding as one, revealed by MaNGA

Implications of the Environments of Radio-detected Active Galactic Nuclei in a Complex Protostructure at z ∼ 3.3

The ALPINE-ALMA [CII] survey

Contact Info

Product

Resources

About