arXiv subjects

Zhi-Yu Zhang

Publications and source records attributed to Zhi-Yu Zhang.

At least 19 recordsLinked to original sources

arXiv2026

Supernova origin of galactic turbulence revealed by superbubbles

Supernovae (SNe) are among the leading candidates for powering galactic-scale turbulence. SNe drive expanding shells of neutral atomic hydrogen (HI) known as superbubbles. Due to the lack of a sensitive, dynamically complete, galaxy-wide census, superbubbles have not been used to quantify the galactic-scale turbulent energy budget. Here we present a combined Five-hundred-meter Aperture Spherical radio Telescope (FAST) and Jansky Very Large Array HI survey of the Andromeda galaxy (M31), the nearest giant spiral, with superior sensitivity and dynamical coverage. We identify 118 superbubbles across the entire disk of M31 with dynamical ages up to 40 Myr, consistent with the expected duration of SN activity in a star cluster and extending the age coverage well beyond previous surveys. Inferred from these superbubbles, the kinetic energy injection rates ($10^{49}$--$10^{51.5}$ erg kpc$^{-3}$ Myr$^{-1}$) from SNe closely match the turbulence dissipation rates derived independently from the same data, in both magnitude and spatial distribution. These results demonstrate that clustered SN feedback is sufficient to sustain galactic-scale turbulence, which shapes disk structure and influences galaxy evolution.

astro-ph.GA↗

arXiv2026

Low Star Formation Efficiency in M31: Evidence for a Deficit of Bound Gas

The Andromeda galaxy (M31) exhibits a systematically low star formation efficiency (SFE) compared to other star-forming galaxies. Star formation is thought to be regulated by the mass of gravitationally bound gas. To investigate whether the low SFE in M31 originates from a scarcity of such bound gas, we analyze the dynamical state of its giant molecular cloud (GMC) population by estimating their virial parameters ($α_{\rm vir}$). Using a JCMT-SCUBA2 850 micron dust-continuum GMC catalog as the parent sample, we combine it with IRAM 30 m CO(1-0) data to define a working sample of 173 GMCs and derive their kinematic properties. Most analyzed GMCs exhibit high $α_{\rm vir}$, indicating that they are predominantly gravitationally unbound at the approximately 86 pc resolution of our observations. While no statistically significant global correlation is found between SFE and $α_{\rm vir}$ for the full cloud sample, the upper quantiles of the SFE distribution show progressively stronger negative trends with increasing $α_{\rm vir}$. This upper-tail trend may arise from the combined effects of the virial parameter limiting the upper range of SFE values accessible to the GMC population and feedback-driven disruption reducing the number of high-SFE, high-$α_{\rm vir}$ CO-bright clouds in the observed sample. The substantial scatter in the SFE-$α_{\rm vir}$ plane likely reflects the diverse evolutionary stages of GMCs, the temporal mismatch between gas and star formation tracers, and the limitations of a cloud-averaged virial parameter as a tracer of internal dynamical structure, making a simple one-to-one correspondence between $α_{\rm vir}$ and instantaneous SFE difficult to recover for individual GMCs.

astro-ph.GA↗

arXiv2026

Individual Star Sampling in Star Formation Simulations: A Semi-Deterministic Model

In modern simulations that include star formation, it is common to use a universal and invariant initial mass function (IMF) to represent star populations or sample individual stars. However, stellar masses are determined by local and environmental processes that operate over a wide dynamical range and remain unresolved in simulations. We introduce a semi-deterministic (SDT) scheme for sampling individual stars from star-forming gas in numerical simulations. We represent unresolved molecular cores and protostellar disks with reservoir particles (RsvPs) and employ an on-the-fly friends-of-friends algorithm to identify star clusters. The instantaneous IMF for newly formed stars is then derived from the current cluster mass. We test the performance of this method in simulations of isolated molecular clouds and a major merger between two dwarf galaxies. Compared to existing IMF sampling methods, our SDT scheme naturally reproduces the observed $m_{\star,\text{max}}$-$M_\text{ecl}$ relation and yields numbers of massive stars consistent with optimal sampling theory. It also exhibits the smallest run-to-run variation among simulations with different random seeds. The regulated star formation results in a small ($\sim0.15$ Myr) but coherent time delay in the emergence of massive stars, reduces the large scatter arising from Poisson noise, and produces initial mass segregation within the clusters. On galactic scales, the SDT method predicts a steeper high-mass IMF slope at low star formation rates (SFRs), with the slope negatively correlated with the SFR. As the specific abundance of massive stars declines, our model naturally explains the systematically low H$α$-based SFRs, where the H$α$ indicator for Milky Way-like galaxies underestimate the intrinsic SFR owing to the reduced population of massive stars.

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arXiv2026

MIAO-ALMA: Shocks and Protostellar Outflows in 70 $μ$m-dark clumps with $L/M$ $<$ 1 $L_{\odot}$/$M_{\odot}$

To investigate the initial conditions of high-mass star-forming regions, we use SiO (2-1) emission to trace early shock-related kinematics toward sixteen 70 $μ$m-dark and massive clumps with luminosity-to-mass ratios ($L/M$) $< 1\,L_{\odot}/M_{\odot}$, as part of the Multiwavelength Line-Imaging Survey of the 70 $μ$m-dark and bright clouds (MIAO) project. Using ALMA observations at a spatial resolution of $\sim$0.06 pc and a velocity resolution of 0.21 km s$^{-1}$, we identify a total of thirty-seven outflows with a variety of morphologies. Outflow parameters were derived by integrating the HCO$^+$ (1-0) line wings, excluding the quiescent dense core component traced by H$^{13}$CO$^+$ (1-0). We find that outflow masses and velocities show moderate positive correlations with the masses of their driving cores. Owing to the high sensitivity of our observations, which yield longer projected outflow lengths compared to previous studies, the derived outflow dynamical ages span $\sim10^{3}$-$10^{5}$ yr. We detect six narrow-linewidth (0.6-1.4 km s$^{-1}$) and three broad ($>$ 2 km s$^{-1}$) SiO (2-1) features not associated with outflows driven by clearly identified protostars. Lacking coincident 3 mm dust continuum cores, their origins may be young outflows from undetected low-mass protostars, dissipating shocks, cloud-cloud collisions, or projection effects when the outflows lie close to the plane of the sky. The detection of these shocks and outflows in such extremely young environments demonstrates that protostellar activity has already begun.

astro-ph.GA↗

arXiv2026

Trace the Self-Gravitating Gas Using CO Isotopologues

Recent studies have shown that the star formation rate (SFR) correlates tightly and linearly with the mass of gravitationally bound gas, which can be delineated from the power-law tail of the column-density probability distribution function ($N$-PDF) derived from dust emission observations. This relationship holds across four orders of magnitude within the Milky Way--spanning low-mass to high-mass star-forming regions and encompassing the extreme environment of the Central Molecular Zone. Building on this framework, we present a new approach for estimating the mass of gravitationally bound gas in molecular clouds using multi-line CO isotopologue observations. Our sample includes 16 molecular clouds with robust detections in $^{12}$CO, $^{13}$CO, and C$^{18}$O $J$ = 1-0, spanning both massive inner Galaxy clouds and nearby star-forming regions. We find that the $N$-PDFs derived from combined CO isotopologue data recover the characteristic log-normal plus power-law profiles seen in dust-based studies. The mass and spatial distribution of the self-gravitating structures estimated from both dust-based and CO-based methods agree well throughout the sample. This indicates that the CO isotopologue combination can robustly trace the self-gravitating component via the $N$-PDF method and provides a reliable, scalable, and velocity-resolved alternative to dust emission for identifying the star-forming gas in molecular clouds.

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arXiv2026

Spatially resolved thermal dust emission in the L1157 outflow reveals grain-driven molecular enrichment

Protostellar outflow shocks reshape local dust properties and molecular chemistry. The L1157 outflow is an archetypal chemically rich shocked region, but the thermal dust associated with its successive shocks has remained unresolved because molecular-line contamination obscures the broadband continuum. We obtained new James Clerk Maxwell Telescope (825--906 $μ$m) spectral-line observations and Submillimeter Array (1.1--1.4 mm) continuum observations toward L1157 B0-B1-B2, probing spatial scales from 0.4 pc to 1200 au. After removing molecular-line contamination on a pixel-by-pixel basis, we derived the dust temperature, column density, and dust opacity index from continuum data spanning 70 $μ$m to 1.3 mm. The line-corrected continuum maps reveal the dust distribution across successive shocks. The dust opacity index ($β\approx1.8$--2.3) indicates that grains have not grown to millimeter sizes throughout the shocked regions. Combined with previous $\rm NH_3$ observations, we find that the dust emission resolves into compact clumps along the precessing jet, whereas gaseous $\rm NH_3$ peaks at the shock fronts, reaching abundances of $\sim10^{-5}$ relative to $\rm H_2$, even where the 0.85 and 1.3 mm dust emission is detected at only 3--5$σ$. Our newly developed physicochemical shock model shows that $\rm NH_3$ forms predominantly on grain surfaces and is released by shock-induced sputtering, with the highest abundances occurring where post-shock re-adsorption remains inefficient. These results establish spatially resolved dust continuum imaging as a direct observational probe of grain evolution and provide new observational constraints on dust-gas interactions in protostellar shocks.

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arXiv2026

Anomalously high deuterium fractionation in a galactic translucent cloud: a challenge to chemical models

Deuterated (D-) species have long been proposed to diagnose the physical conditions and chemical evolution of cold dense molecular clouds. While deuterium fractionation has been extensively measured in dense cores, observations in diffuse and translucent clouds remain rare. We report here the detection of DCN and DNC toward a translucent cloud ($A_{\rm V} =1.2\pm0.2$ mag, $n_{\rm H_2}$ = $3.9\pm0.2\times10^2$ cm$^{-3}$) through sensitive absorption observations with the IRAM NOrthern Extended Millimeter Array (NOEMA). This detection reaches the lowest column-density and volume-density regime in which deuteration has been observed so far. Interestingly, the observed DCN/HCN and DNC/HNC abundance ratios ($3.3\pm0.6\times10^{-3}$ and $3.6\pm1.2\times10^{-3}$, respectively), which are more than two orders of magnitude higher than the element abundance [D]/[H] (1.5$\times$10$^{-5}$), suggest an unexpected enhancement of deuterium fractionation in the translucent cloud. These results represent a significant departure from established chemical models considering deuterium fractionation, which predict negligible formation of D-molecules in such environments. Although it remains unclear how D-molecules built up their abundances in translucent gas, a dispersed dense core scenario could potentially explain the observed high deuterium fraction. This interpretation is consistent with the idea proposed by Price et al. (2003) more than two decades ago: a translucent cloud may be a transient, dynamically evolving structure formed through the dissipation of a dense molecular cloud.

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arXiv2026

Ram-pressure stripping caught in action in a young cluster at $z = 2.51$

Galaxy clusters in the local Universe are dominated by massive quiescent galaxies with old ages, formed at high redshifts. Whether their quenching is driven by internal processes or environmental effects is a matter of debate that has been challenging to resolve due to the lack of observations during their peak formation epoch. Here we report clear evidence from the Atacama Large Millimeter/submillimeter Array of extended and elongated gas tails in five galaxies in a forming cluster at z = 2.51. The single-tailed gas distributions, which extend notably beyond the stellar emission probed by JWST in galaxies that are relatively isolated and lack signatures of mergers or interactions (features that are very uncommon in the field), provide evidence of ram-pressure stripping. These very distant confirmed cases of ram-pressure stripping highlight the critical role of environmental effects in gas removal at high redshifts, an often-overlooked quenching pathway.

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arXiv2026

Limited imprint of high-mass IMF variations on sodium abundances in main-sequence galaxies

Growing evidence suggests that the stellar initial mass function (IMF) varies systematically across galaxies, deviating from the canonical Milky Way form. Such variations would modify the integrated nucleosynthetic yields, and hence the abundance patterns used in stellar population synthesis studies. How these could impact, in particular, the sodium abundance (and sodium-to-oxygen ratios) in star-forming galaxies is not well understood. In this work, we systematically study how high-mass IMF variations affect sodium enrichment using a one-zone galactic chemical evolution model. The model incorporates star formation histories from semi-analytic simulations and is calibrated to match the observed galaxy mass--metallicity relation. We find that varying the IMF high-mass end (and the IMF slope) could only alter the sodium abundance by less than 0.1 dex, across galaxies with stellar masses from $10^9\,\mathrm{M}_\odot$ to $10^{11}\,\mathrm{M}_\odot$. This result is robust under different stellar models and galaxy evolution assumptions, primarily because sodium production is similar to that of oxygen. We conclude that sodium abundance is largely insensitive to changes in the high-mass IMF, unlikely to compromise the use of sodium indices as IMF diagnostics in stellar population studies.

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arXiv2026

The Cocoon from a Massive Star's Death: VLA Radio Polarization Study of Possible Historical Supernova Remnant G7.7$-$3.7

G7.7$-$3.7 is a possible historical SNR, with the origin of its cocoon-like morphology and its supernova type remaining unclear. We performed L-band radio polarization observations of G7.7$-$3.7 using the Very Large Array in C and B-configurations. The high-resolution 1.4 GHz continuum image reveals a cocoon-like morphology with multiple shells and faint blowout structures. The total flux density is 9.6$\pm$0.5 Jy and the spectral index map shows predominantly nonthermal emission, with an integrated spectral index of $-$0.38$\pm$0.04. Polarization images of G7.7$-$3.7 show high linear polarization fraction (30%-40%) in the northwestern filaments and moderate polarization (10%-20%) in the northeast and south. The magnetic fields aligned with the filamentary structures, consistent with shock compression. Large rotation measure (RM) variations across the SNR likely originate from magnetized massive progenitor winds. We suggest that the cocoon-like morphology results from the interaction between the SNR and pre-existing circumstellar shells, demonstrating that the radio polarization provides useful constraints on the environments and even the progenitor mass-loss.

astro-ph.HE↗

arXiv2026

Discovery of a radio jet in the Cloverleaf Quasar at z = 2.56

The fast growth of supermassive black holes and their feedback to the host galaxies play an important role in regulating the evolution of galaxies, especially in the early Universe. However, due to cosmological dimming and the limited angular resolution of most observations, it is difficult to resolve the feedback from the active galactic nuclei (AGNs) to their host galaxies. Gravitational lensing, for its magnification, provides a powerful tool to spatially differentiate emission originating from AGN and host galaxy at high redshifts. Here we report a discovery of a jet-like radio structure in a strongly lensed starburst quasar, H1413+117 or Cloverleaf at redshift z= 2.56, based on observational data at optical, sub-millimetre, and radio wavelengths. With both parametric and non-parametric lens models and with reconstructed images in the source plane, we find a well-separated, kpc-scaled, single-sided radio jet located at projected ~1.2 kpc to the northwest of the host galaxy in the source plane. This could indicate the co-existence of feedback from the AGN by both wind and jet in the Cloverleaf quasar.

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arXiv2025

$^{12}$CO $J$=3--2 Observations of Tycho's supernova remnant: constraints on the environmental gas properties

Recent observations suggest that Tycho's supernova remnant (SNR; SN 1572) is expanding into a cavity wall of molecular clouds (MCs), which decelerate the SNR and influence its multi-wavelength morphology. To constrain the physical properties of environmental MCs and search for heated gas, we perform a JCMT $^{12}$CO $J$=3--2 observation and compare with previous $^{12}$CO $J$=2--1, $^{12}$CO $J$=1--0 and $^{13}$CO $J$=1--0 data. We present the $^{12}$CO $J$=3--2 map toward Tycho and show that the $^{12}$CO $J$=3--2 spatial distribution and line profiles are similar to those of the lower-$J$ CO lines. By comparing the multiple transitions of CO and the RADEX (Radiative transfer code in non-Local Thermodynamic Equilibrium) models, we constrain the physical properties of molecular gas surrounding Tycho: the northern cloud has a molecular column density of $N({\rm H}_{2})=0.5$ -- $4.5\times 10^{22}$ cm$^{-2}$, while other regions have $N({\rm H}_{2})=0.2$ -- $3.9\times10^{21}$ cm$^{-2}$; the kinetic temperatures $T_{\rm k}$ of these clouds are in the range of 9 -- 22 K and the volume densities $n({\rm H}_{2})$ are 20 -- $700$ cm$^{-3}$. We also discuss the difficulty in finding hot molecular gas shocked by such a young SNR. We estimate that the shocked molecular layer can be as thin as 0.003 pc, corresponding to $0.2''$ at the distance of 2.5 kpc, which is 2 orders of magnitude smaller than the angular resolution of current CO observations. Therefore, our molecular observations are largely insensitive to the thin shocked gas layer; instead, they detect the environmental gas.

astro-ph.GA↗

arXiv2025

The MALATANG survey: star formation, dense gas, and AGN feedback in NGC 1068

We aim to investigate the interplay between dense molecular gas, star formation, and active galactic nucleus (AGN) feedback in the luminous infrared galaxy (LIRG) NGC 1068 at sub-kiloparsec scales. We present the HCN (4-3) and HCO$^+$ (4-3) maps of NGC 1068, obtained with JCMT as part of the Mapping the dense molecular gas in the strongest star-forming galaxies (MALATANG) project, and perform spatially resolved analyses of their correlations with infrared luminosity and soft X-ray emission. Spatially resolved relations between the luminosities of infrared dust emission and dense molecular gas tracers ($L_{\rm IR}-L'_{\rm dense}$) are found to be nearly linear, without clear evidence of excess contributions from AGN activity. The spatially resolved X-ray emission ($L^{\rm gas}_{0.5-2\,\mathrm{keV}}$) displays a radially-dependent twofold correlation with the star formation rate (SFR), suggesting distinct gas-heating mechanisms between the galaxy center and the outer regions. A super-linear scaling is obtained in galactic center regions with SFR surface density ($Σ_{\rm SFR}$) $>$ 8.2 $\times$ 10$^{-6}$ $M_\odot$ yr$^{-1}$ kpc$^{-2}$: log($L^{\rm gas}_{0.5-2\,\mathrm{keV}}$/erg s$^{-1}$) = 2.2 log(SFR/$M_\odot$ yr$^{-1}$) + 39.1. We further found a statistically significant super-linear correlation ($β= 1.34$ $\pm$ 0.86) between $L^{\rm gas}_{0.5-2\,\mathrm{keV}}$/SFR and HCN(4-3)/CO(1-0) intensity ratio, whereas no such trend is seen for HCO$^+$(4-3)/CO(1-0) or CO(3-2)/CO(1-0). These findings indicate that AGN feedback does not dominate star formation regulation on sub-kiloparsec scales, and that the excitation of dense gas traced by HCN (4-3) may be more directly influenced by high-energy feedback processes compared to HCO$^+$ (4-3) and CO (3-2).

astro-ph.GA↗

arXiv2025

Tails of Gravity: Persistence of Star Formation in the CMZ Environment

We characterize star-forming gas in six molecular clouds (Sgr B1-off, Sgr B2, Sgr C, the 20 km s$^{-1}$ and 50 km s$^{-1}$ molecular clouds, and the Brick) in the Galactic central molecular zone (CMZ), and compare their star-forming activities with those in molecular clouds outside the CMZ. Using multi-band continuum observations taken from ${\it Planck}$, ${\it Herschel}$, JCMT/SCUBA-2, and CSO/SHARC2, we derived 8.5" resolution column density maps for the CMZ clouds and evaluated the column density probability distribution functions (N-PDFs). With the archival Atacama Large Millimeter/submillimeter Array (ALMA) 1.3 mm dust continuum data, we further evaluated the mass of the most massive cores ($M_{\rm core}^{\rm ma x}$). We find that the N-PDFs of four of the selected CMZ clouds are well described by a piecewise log-normal + power-law function, while the N-PDFs of the remaining two can be approximated by log-normal functions. In the first four targets, the masses in the power-law component ($M_{\rm gas}^{\rm bound}$), $M_{\rm core}^{\rm max}$, and star formation rate (SFR) are correlated. These correlations are very similar to those derived from low-mass clouds in the Solar neighborhood and massive star-forming regions on the Galactic disk. These findings lead to our key hypotheses: (1) In the extreme environment of the CMZ, the power-law component in the N-PDF also represents self-gravitationally bound gas structures, and (2) evolution and star-forming activities of self-gravitationally bound gas structures may be self-regulated, insensitive to the exterior environment on $\gtrsim$5-10 pc scales.

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arXiv2025

Deep Andromeda JCMT-SCUBA2 Observations. The Submillimeter Maps and Giant Molecular Clouds

We have carried out unprecedentedly deep, nearly confusion-limited JCMT-SCUBA2 mapping observations on the nearest spiral galaxy, M31 (Andromeda). The 850 $μ$m image with a $\sim$50 pc resolution yields a comprehensive catalog of 383 giant molecular clouds (GMCs) that are associated with the spiral arms. In addition, it unveiled a population of 189 compact inter-arm GMCs in M31, which are mostly unresolved or marginally resolved. The masses of all these GMCs are in the range of 2$\times$10$^4$ -- 6$\times$10$^6$ $M_{\odot}$; the sizes are in the range of 30--130 pc. They follow a mass-size correlation, $M$ $\propto$ $R_{c}$$^{2.5}$. The inter-arm GMCs are systematically less massive, more diffuse, colder, and have lower star-forming efficiency (SFE) than on-arm GMCs. Moreover, within individual spatially resolved on-arm and off-arm M31 GMCs, the SFE is considerably lower than the SFE in molecular clouds in main sequence and green valley galaxies. Follow-up investigations on M31 GMCs may provide clues for how star formation may be quenched in galactic environments. Finally, we reconstrained the dust opacity spectral index $β$ in the M31 galaxy by combining our new JCMT observations with archival Herschel and Planck data and found that the radial variation of $β$ may not be as large as was proposed by previous studies.

astro-ph.GA↗

arXiv2025

Molecular gas content of gravitational-lensed quasars at cosmic noon

Star-forming activity in the host galaxies of high-redshift quasars is crucial to understanding the connection between supermassive black hole (SMBH) activity and galaxy evolution. While most existing studies are biased toward luminous quasars, we conduct carbon monoxide (CO) observations of 17 gravitationally lensed quasars that have four images using the IRAM 30m telescope to investigate the molecular gas content of moderate- to low-luminosity quasars. CO emissions are detected in five out of 17 quasars, corresponding to a detection rate of about 30\%. Analysis of their star formation activity reveals that these quasars live in gas-rich environments but exhibit weaker starbursts and lower star formation efficiencies compared to other luminous high-redshift quasars. In addition, the CO spectral line energy distributions of the two quasars (SDSS J0924+0219, SDSS J1330+1810) are also consistent with mild star formation instead of extreme starbursts. These results suggest that these lensed quasars reside in weaker starburst environments.

astro-ph.GA↗

arXiv2025

ALMA Deep Field in SSA22: Reconstructed [CII] Luminosity Function at z = 6

The ADF22 line survey reported detections of two high-$z$ line-emitting source candidates above 6-$σ$, both of which were shown to be spurious after follow-up observations. We investigate the detectability of far-infrared emitters in ALMA deep fields using mock observations by injecting artificial line-emitting sources into the visibility planes. We also discuss our investigation, conducted together with the ALMA operations team, of a possible technical problem in the original observations. Finally, we devise a method to estimate the [CII] luminosity function (LF) at $z \sim 6$, including a full analysis of signal contamination and sample completeness. The comparison of pixel distributions between the real and mock datacubes does not show significant differences, confirming that the effect of non-Gaussian noise is negligible for the ADF22 datacube. Using 100 blank mock-mosaic datasets, we show 0.43 $\pm$ 0.67 false detections per datacube with the previous source-finding method. We argue that the underestimation of the contamination rate in the previous work is caused by the smaller number of datacubes, using only 4 real ADF22 datacubes. We compare the results of clump-finding between the time division mode and frequency division mode correlator datacubes and confirm that the velocity widths of the clumps in the TDM case are up to 3 times wider than in the FDM case. The LF estimation using our model shows that a correction for the number count is required, up to one order of magnitude, in the luminosity range of $\geq 5 \times 10^8 L_\odot$. Our reconstruction method for the line LF can be applied to future blind line surveys.

astro-ph.GA↗

arXiv2025

Serendipitous Discovery of an Optically-Dark Ultra-Luminous Infrared Galaxy at $z$ = 3.4

Dusty, submillimeter-selected galaxies without optical counterparts contribute a non-negligible fraction of the star formation in the early universe. However, such a population is difficult to detect through classical optical/UV-based surveys. We report the serendipitous discovery of such an optically dark galaxy, behind the quadruply-lensed $z=2.56$ quasar, H1413+117, offset to the north by 6\arcsec. From $^{12}$CO $J=4$--3, $J=6$--5, and part of the $J=13$--12 transitions, which all spatially coincide with a compact submillimeter continuum emission, we determine an unambiguous spectroscopic redshift, $z=3.386\pm 0.005$. This galaxy has a molecular mass $M_{\rm mol} \sim 10^{11}$ M$_\odot$ and a black hole mass $M_{\rm BH} \sim 10^{8}$ M$_\odot$, estimated from $^{12}$CO $J=4$--3 and archival {\it Chandra} X-ray data ($L_{\rm 2-10,keV} \sim 4 \times 10^{44}$\,erg\,s$^{-1}$), respectively. We also estimate a total infrared luminosity of $L_{\rm FIR} = (2.8\pm{2.3}) \times 10^{12}$ L$_\odot$ and a stellar mass of $M_* \lesssim 10^{11}$ M$_{\odot}$, from spectral energy distribution fitting. According to these simple mass estimations, this gas-rich and X-ray bright galaxy might be in a transition phase from starburst to quasar offering a unique case for studying galaxy-black hole co-evolution under extremely dusty conditions.

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