A5028329336- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Astrophysics and Cosmic Phenomena
- Adaptive optics and wavefront sensing
- Radio Astronomy Observations and Technology
- History and Developments in Astronomy
- Photocathodes and Microchannel Plates
- Particle accelerators and beam dynamics
- Impact of Light on Environment and Health
- Spectroscopy and Laser Applications
- Pulsars and Gravitational Waves Research
- Particle Accelerators and Free-Electron Lasers
- Scientific Research and Discoveries
- Astronomical Observations and Instrumentation
- Atmospheric Ozone and Climate
- CCD and CMOS Imaging Sensors
- Remote Sensing in Agriculture
- History and Theory of Mathematics
- Conferences and Exhibitions Management
- Cosmology and Gravitation Theories
- Relativity and Gravitational Theory
University of British Columbia
2021-2024
Canadian Institute for Theoretical Astrophysics
2018-2023
University of Toronto
2018-2023
National Observatory
2022
Valongo Observatory
2022
European Southern Observatory
2015-2019
University of Copenhagen
2011-2016
University of Hawaii System
2013-2016
Three billion years after the big bang (at redshift z=2), half of most massive galaxies were already old, quiescent systems with little to no residual star formation and extremely compact stellar mass densities at least an order magnitude larger than in low ellipticals, their descendants. Little is known about how they formed, but evolved, dense populations suggest within intense, starbursts 1-2 Gyr earlier 3<z<6). Simulations show that gas-rich major mergers can give rise such which produce...
Abstract We present the first results from Mapping Obscuration to Reionization with ALMA (MORA) survey, largest Atacama Large Millimeter/submillimeter Array (ALMA) blank-field contiguous survey date (184 arcmin 2 ) and only at mm search for dusty star-forming galaxies (DSFGs). use 13 sources detected above 5 σ estimate galaxy number counts this wavelength. These are then combined state-of-the-art 1.2 3 a backward evolution model place constraints on of IR luminosity function dust-obscured...
We present dynamical and structural scaling relations of quiescent galaxies at z=2, including the mass-size relation first constraints on fundamental plane (FP). The backbone analysis is a new, very deep VLT/X-shooter spectrum massive, compact, galaxy z=2.0389. detect continuum between 3700-22000A several strong absorption features (Balmer series, Ca H+K, G-band), from which we derive stellar velocity dispersion 318 +/- 53 km/s. perform detailed modeling emission line indices simultaneous...
Early assembly of a galaxy disk and bulge Galaxy formation in the early Universe is thought to have been chaotic process, producing disturbed asymmetric morphologies. Over billions years, galaxies dynamically relaxed form stable morphological features. Lelli et al. observed distant at redshift when was 1.2 billion years old (see Perspective by Wardlow). They used gas dust emission measure its kinematics, then modeled mass distribution within galaxy. The authors found that contains massive...
Abstract We present the characteristics of 2 mm selected sources from largest Atacama Large Millimeter/submillimeter Array (ALMA) blank-field contiguous survey conducted to date, Mapping Obscuration Reionization with ALMA (MORA) covering 184 arcmin at mm. Twelve 13 detections above 5 σ are attributed emission galaxies, 11 which dominated by cold dust emission. These have a median redshift <?CDATA $\langle {z}_{2\,\mathrm{mm}}\rangle ={3.6}_{-0.3}^{+0.4}$?> <mml:math...
The 2mm Mapping Obscuration to Reionization with ALMA (MORA) Survey was designed detect high redshift ($z\gtrsim4$), massive, dusty star-forming galaxies (DSFGs). Here we present two, likely sources, identified in the survey whose physical characteristics are consistent a class of optical/near-infrared (OIR) invisible DSFGs found elsewhere literature. We first perform rigorous analysis all available photometric data fit spectral energy distributions and estimate redshifts before deriving...
Using a mass-selected ($M_{\star} \ge 10^{11} M_{\odot}$) sample of 198 galaxies at 0 < z 3.0 with HST/NICMOS $H_{160}$-band images from the COSMOS survey, we find evidence for evolution pair fraction above ~ 2, an epoch in which massive are believed to undergo significant structural and mass evolution. We observe that is 0.15 \pm 0.08 1.7 3.0, where galaxy pairs defined as having companion flux ratio 1:1 1:4 within projected separation 30 kpc. This slightly lower, but still consistent...
ABSTRACT We measure the merger fraction of massive galaxies using UltraVISTA/COSMOS catalog, complemented with deeper, higher resolution 3DHST+CANDELS presenting largest mass-complete photometric sample up to <?CDATA $z\sim 3$?> . find that variation in mass ratio probe can explain discrepant redshift evolution literature: selecting mergers H 160 -band flux leads an increasing redshift, while stellar reveals a little dependence at $z=1\mbox{--}3$?> Defining major and minor as having ratios...
We present ALMA detections of the [CI] 1-0, CO J=3-2, and J=4-3 emission lines, as well band 4 continuum for a compact star-forming galaxy (cSFG) at z=2.225, 3D-HST GS30274. As is typical cSFGs, this has stellar mass $1.89 \pm 0.47\,\times 10^{11}\,\rm{M}_\odot$, with star formation rate $214\pm44\,\rm{M}_\odot\,\rm{yr}^{-1}$ putting it on `main-sequence', but an H-band effective radius 2.5 kpc, making much smaller than bulk `main-sequence' galaxies. The intensity ratio line yield ISM...
We present and analyse an extensive dataset of the superluminous supernova (SLSN) LSQ14mo (z = 0.256), consisting a multi-colour lightcurve from -30 d to +70 in rest-frame series 6 spectra PESSTO covering -7 +50 d. This is among densest spectroscopic coverage, best-constrained rising lightcurve, for fast-declining hydrogen-poor SLSN. The bolometric can be reproduced with millisecond magnetar model ~ 4 M_sol ejecta mass, temperature velocity evolution also suggestive as power source. Spectral...
The dust-to-stellar mass ratio ( M dust / ⋆ ) is a crucial, albeit poorly constrained, parameter for improving our understanding of the complex physical processes involved in production dust, metals, and stars galaxy evolution. In this work, we explore trends with different parameters using observations 300 massive dusty star-forming galaxies detected ALMA up to z ≈ 5. Additionally, interpret findings models formation. We find that evolves redshift, stellar mass, specific star formation...
Galaxy interactions/mergers have been shown to dominate the population of IR-luminous galaxies (LIR ≳ 1011.6 L☉) in local universe (z ≲ 0.25). Recent studies based on relation between galaxies' star formation rates and stellar mass (the SFR–M* or "galaxy main sequence") suggested that galaxy interaction/mergers may only become significant when fall well above sequence. Since typical SFR at a given M* increases with redshift, existence sequence implies massive, high z not necessarily be...
We present stringent constraints on the average mid-, far-infrared and radio emissions of $\sim$14200 quiescent galaxies (QGs), identified out to $z=3$ in COSMOS field via their rest-frame NUV$-$r r$-$J colors, with stellar masses $M_{\star}=10^{9.8-12.2} \,M_{\odot} $. Stacking deep Spitzer (MIPS $24\,\mu$m), Herschel (PACS SPIRE), VLA (1.4 GHz) maps reveals extremely low dust-obscured star formation rates for QGs (SFR $<0.1-3\,M_{\odot}$yr$^{-1}$ at $z \leqslant 2$...
ABSTRACT We present spatially resolved H α properties of 21 type 1 AGN host galaxies at z ∼ 2 derived from the SUPER survey. These targets were observed with adaptive optics capabilities SINFONI spectrograph, a near-infrared integral field that provided median spatial resolution 0.3 arcsec (∼2 kpc). model emission line profile in each pixel to investigate whether it traces gas narrow region or if is associated star formation. To do this, we first presence after subtracting PSF. find extended...
We present deep, near-infrared HST/WFC3 grism spectroscopy and imaging for a sample of 14 galaxies at z~2 selected from mass-complete photometric catalog in the COSMOS field. By combining observations with photometry 30 bands, we derive accurate constraints on their redshifts, stellar masses, ages, dust extinction formation redshifts. show that slope scatter mass-size relation quiescent is consistent local relation, confirm previous findings sizes given mass are smaller by factor two to...
We present rest-frame optical spectra from the FMOS-COSMOS survey of twelve $z \sim 1.6$ \textit{Herschel} starburst galaxies, with Star Formation Rate (SFR) elevated by $\times$8, on average, above star-forming Main Sequence (MS). Comparing H$α$ to IR luminosity ratio and Balmer Decrement we find that optically-thin regions sources contain average only $\sim 10$ percent total SFR whereas $\sim90$ comes an extremely obscured component which is revealed far-IR observations optically-thick...
We present a detailed analysis of large sample spectroscopically confirmed ultra-massive quiescent galaxies (${\rm{log}}(M_{\ast}/M_{\odot})\sim11.5$) at $z\gtrsim2$. This comprises 15 selected in the COSMOS and UDS fields by their bright K-band magnitudes followed up with VLT/X-shooter spectroscopy HST/WFC3 $H_{F160W}$ imaging. These observations allow us to unambiguously confirm redshifts ascertain nature stellar ages, reliably assess internal kinematics effective radii. find that these...
The physical mechanisms that link the termination of star formation in quiescent galaxies and evolution their baryonic components, stars, interstellar medium (ISM; dust, gas, metals) are poorly constrained beyond local Universe. In this work, we characterise dust content 545 observed at 0.1 < z 0.6 as part hCOSMOS spectroscopic redshift survey. This is, to date, largest sample intermediate redshifts for which stellar, metal abundances consistently estimated. We analyse how crucial markers...
The broad-line region (BLR) of active galactic nuclei (AGNs) traces gas close to the central supermassive black hole (BH). Recent reverberation mapping (RM) and interferometric spectro-astrometry data have enabled detailed investigations BLR structure dynamics as well estimates BH mass. These exciting developments motivated comparative structures using different broad emission lines. In this work, we developed a method simultaneously model multiple lines from single-epoch spectrum. We...
While performing a survey to detect recoiling supermassive black holes, we have identified an unusual source having projected offset of 800 pc from nearby dwarf galaxy. The object, SDSS J113323.97+550415.8, exhibits broad emission lines and strong variability. originally classified as supernova (SN) because its non-detection in 2005, it recent past observations over 63 yr find magnitude rebrightening the last 2 yr. Using high-resolution adaptive optics observations, constrain region be ≲12...
We present a multiwavelength study of the AGN-host starburst galaxy PKS 0529-549 at |$z$| ≃ 2.6. use (1) new ALMA observations dust continuum and [Ci] 370 |$\mu$|m line, tracing molecular gas, (2) SINFONI spectroscopy [O iii] 5007 Å ionized (3) ATCA radio images, synchrotron emission. Both [C i] show regular velocity gradients, but their systemic velocities position angles differ by ∼300|$\, \mathrm{km}\, \mathrm{s}^{-1}$| ∼30°, respectively. The is consistent with rotating disc, aligned...
Abstract The systematic targeting of extended Ly α emission around high-redshift quasars resulted in the discovery rare and bright Enormous Nebulae (ELANe) associated with multiple active galactic nuclei (AGNs). We initiate here “a multiwavelength study ELAN environments” (AMUSE 2 ) focusing on z ∼ 3 quasar SDSS J1040+1020, aka Fabulous ELAN. report VLT/HAWK-I, APEX/LABOCA, JCMT/SCUBA-2, SMA/850 μ m, ALMA CO(5-4), mm observations compare them to previously published VLT/MUSE data. continuum...
We present a physical characterization of MMJ100026.36+021527.9 (a.k.a. ``MAMBO-9''), dusty star-forming galaxy (DSFG) at $z=5.850\pm0.001$. This is the highest redshift unlensed DSFG (and fourth most distant overall) found to-date, and first source identified in new 2mm blank-field map COSMOS field. Though prior samples DSFGs 850$\mu$m-1.2mm with unknown redshift, detection prompted further follow-up as it indicated much higher probability that was likely to sit $z>4$. Deep observations...