A5045680475- Astronomy and Astrophysical Research
- Galaxies: Formation, Evolution, Phenomena
- Stellar, planetary, and galactic studies
- Astronomical Observations and Instrumentation
- Astrophysics and Star Formation Studies
- Gamma-ray bursts and supernovae
- Cosmology and Gravitation Theories
- History and Developments in Astronomy
- Astrophysics and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- Dark Matter and Cosmic Phenomena
- Spectroscopy and Laser Applications
- Geophysics and Gravity Measurements
- Photocathodes and Microchannel Plates
- Nuclear physics research studies
- Radio Astronomy Observations and Technology
- Historical Astronomy and Related Studies
- Black Holes and Theoretical Physics
- Radiation Therapy and Dosimetry
- Scientific Research and Discoveries
- Atmospheric Ozone and Climate
- Nuclear Physics and Applications
- Calibration and Measurement Techniques
- CCD and CMOS Imaging Sensors
- Spectroscopy Techniques in Biomedical and Chemical Research
University of British Columbia
2017-2024
Dalhousie University
2023
Imperial College London
2018
Adnet Systems (United States)
2011
Science Systems and Applications (United States)
2007
Goddard Space Flight Center
2007
Clarendon College
1957-1958
SEVEN-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP*) OBSERVATIONS: COSMOLOGICAL INTERPRETATION, E. Komatsu, K. M. Smith, J. Dunkley, C. L. Bennett, B. Gold, G. Hinshaw, N. Jarosik, D. Larson, R. Nolta, Page, Spergel, Halpern, S. Hill, A. Kogut, Limon, Meyer, Odegard, Tucker, Weiland, Wollack, Wright
A simple cosmological model with only six parameters (matter density, Ωmh2, baryon Ωbh2, Hubble constant, H0, amplitude of fluctuations, σ8, optical depth, τ, and a slope for the scalar perturbation spectrum, ns) fits not 3 year WMAP temperature polarization data, but also small-scale CMB light element abundances, large-scale structure observations, supernova luminosity/distance relationship. Using data only, best-fit values power-law flat Λ cold dark matter (ΛCDM) are (Ωmh2,Ωbh2,h,ns,τ,σ8)...
Abstract We have observed the z = 4.3 protocluster SPT2349−56 with Australia Telescope Compact Array (ATCA) aim of detecting radio-loud active galactic nuclei (AGNs) among ∼30 submillimeter (submm) galaxies (SMGs) identified in structure. detect central complex submm sources at 2.2 GHz a luminosity L (4.42 ± 0.56) × 10 25 W Hz −1 . MeerKAT and Australian Square Kilometre Pathfinder also source 816 MHz 888 MHz, respectively, constraining radio spectral index to α −1.45 0.16, implying 1.4,rest...
Abstract We present Atacama Compact Array (ACA) Band-3 observations of the protocluster SPT2349−56, an extreme system hosting >10 ultraluminous infrared galaxies (ULIRGs; L IR ≳ 10 12 ⊙ ) in a 200 kpc diameter region at z = 4.3, to study its integrated molecular gas content via CO(4–3) and long-wavelength dust continuum. The ∼30 hr integration represents one longest exposures yet taken on single pointing with ACA 7 m. low-resolution data (21 <mml:math...
We present an extensive ALMA spectroscopic follow-up programme of the $z\,{=}\,4.3$ structure SPT2349$-$56, one most actively star-forming proto-cluster cores known, to identify additional members using their [C{\sc ii}] 158\,$\mu$m and \mbox{CO(4--3)} lines. In addition robustly detecting 14 previously published galaxies in this structure, we a further 15 associated at $z\,{=}\,4.3$, resolving 55$\,{\pm}\,$5\,per cent 870-$\mu$m flux density 0.5\,arcsec resolution compared 21\,arcsec...
We present the projected Rayleigh statistic (PRS), a modification of classic statistic, as test for non-uniform relative orientation between two pseudo-vector fields. In application here, this gives an effective way investigating whether polarization pseudo-vectors (spin-2 quantities) are preferentially parallel or perpendicular to filaments in interstellar medium. For example, there other potential applications astrophysics, e.g. when comparing small-scale orientations with larger scale...
Abstract We present the initial results of an ongoing survey with Karl G. Jansky Very Large Array targeting CO( J = 1–0) transition in a sample 30 submillimeter-selected, dusty star-forming galaxies (SFGs) at z 2–5 existing mid- CO detections from Atacama Millimeter/submillimeter and NOrthern Extended Millimeter Array, which 17 have been fully observed. detect CO(1–0) emission 11 targets, along three tentative (∼1.5 σ –2 ) detections; are undetected. Our yield total molecular gas masses 6–23...
SPT0311-58 is the most massive infrared luminous system discovered so far during Epoch of Reionization (EoR). In this paper, we present a detailed analysis molecular interstellar medium at z = 6.9, through high-resolution observations CO(6-5), CO(7-6), CO(10-9), [CI](2-1), and p-H2O(211-202) lines dust continuum emission with Atacama Large Millimeter/submillimeter Array (ALMA). The consists pair intensely star-forming gravitationally lensed galaxies (labelled West East). intrinsic...
Abstract We present wide-field mapping at 850 μ m and 450 of the z = 2.85 protocluster in HS 1549+19 field using Submillimetre Common-User Bolometer Array 2. Spectroscopic follow-up 18 bright sources selected m, Northern Extended Millimeter Atacama Large Millimeter/submillimeter Array, confirms that majority lie near ≃ are likely members structure. Interpreting spectroscopic redshifts as distance measurements, we find submillimeter galaxies (SMGs) span 123 pMpc 2 plane sky demarcate a 3600 3...
Abstract We present Atacama Large Millimeter/submillimeter Array observations of the [C I ] 492 and 806 GHz fine-structure lines in 25 dusty star-forming galaxies (DSFGs) at z = 4.3 core SPT2349–56 protocluster. The protocluster exhibit a median <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mi>L</mml:mi> </mml:mrow> <mml:mo stretchy="false">[</mml:mo> <mml:mspace width="0.1em"/> <mml:mtext>C</mml:mtext> <mml:mi mathsize="small"...
We have used the Submillimeter Array at 860$\,\mu$m to observe brightest SCUBA-2 sources in 4$\,$deg$^{2}$ of Cosmology Legacy Survey. targeted 75 single-dish 850$\,\mu$m down $S_{850}\,{\approx}\,8\,$mJy, achieving an average synthesized beam 2.4$^{\prime\prime}$ and rms $\sigma_{860}\,{=}\,1.5\,$mJy our primary beam-corrected maps. searched maps for $4\sigma$ peaks, corresponding $S_{860}\,{\gtrsim}\,6\,$mJy sources, detected 59 single galaxies three pairs galaxies. include study 28...
We present APEX-LABOCA 870 micron observations of the fields surrounding nine brightest, high-redshift, unlensed objects discovered in South Pole Telescope's (SPT) 2500 square degrees survey. Initially seen as point sources by SPT's 1-arcmin beam, 19-arcsec resolution our new data enables us to deblend these and search for submillimetre (submm) fields. find a total 98 above threshold 3.7 sigma observed area 1300 arcminutes, where bright central cores resolve into multiple components. After...
We present the average rest-frame spectrum of final catalog dusty star-forming galaxies (DSFGs) selected from South Pole Telescope SZ survey (SPT-SZ) and measured with Band 3 Atacama Large Millimeter/submillimeter Array (ALMA). This work builds on previous spectrum, given in Spilker et al. (2014) for first 22 sources, is comprised a total 78 normalized by their respective apparent dust masses. The spans $1.9$$<$z$<$$6.9$ covers frequencies 240$-$800 GHz. Combining this data low-J CO...
Abstract We present JWST and Atacama Large Millimeter/submillimeter Array (ALMA) imaging for the lensing system SPT0418−47, which includes a strongly lensed, dusty, star-forming galaxy at redshift z = 4.225 an associated multiply imaged companion. The NIRCam MIRI observations presented in this paper were acquired as part of Early Release Science program Targeting Extremely Magnified Panchromatic Lensed Arcs Their Extended Star formation (TEMPLATES). This data set provides robust...
We present Gemini-S and {\it Spitzer}-IRAC optical-through-near-IR observations in the field of SPT2349-56 proto-cluster at $z=4.3$. detect optical/IR counterparts for only nine 14 submillimetre galaxies (SMGs) previously identified by ALMA core SPT2349-56. In addition, we four $z\sim4$ Lyman-break (LBGs) 30 arcsec diameter region surrounding this core. Three LBGs are new systems, while one appears to be a counterpart observed SMGs. identify candidate brightest cluster galaxy (BCG) with...
The SPT0311-58 system at z=6.900 is an extremely massive structure within the reionization epoch, and offers a chance to understand formation of galaxies in extreme peak primordial density field. We present 70mas Atacama Large Millimeter/submillimeter Array observations dust continuum CII 158um emission central pair reach physical resolution ~100-350pc, among most detailed views any reionization-era date. resolve source into least dozen kiloparsec-size clumps. global kinematics high...
Cosmic background (CB) radiation, encompassing the sum of emission from all sources outside our own Milky Way galaxy across entire electromagnetic spectrum, is a fundamental phenomenon in observational cosmology. Many experiments have been conceived to measure it (or its constituents) since extragalactic Universe was first discovered; addition estimating bulk (cosmic monopole) directional variations also detected over wide range wavelengths. Here we gather most recent these measurements and...
Galaxy clusters at high redshift are key targets for understanding matter assembly in the early Universe, yet they challenging to locate. A sample of >2000 high-z candidate structures has been found using Planck's all-sky submm maps, and a sub-set 234 have followed up with Herschel-SPIRE, which showed that emission can be attributed large overdensities dusty star-forming galaxies. In order resolve characterise individual galaxies we targeted eight brightest SPIRE sources centre Planck peak...
The protocluster SPT2349$-$56 at $z\,{=}\,4.3$ contains one of the most actively star-forming cores known, yet constraints on total stellar mass this system are highly uncertain. We have therefore carried out deep optical and infrared observations system, probing rest-frame ultraviolet to wavelengths. Using positions spectroscopically-confirmed members, we identify counterparts perform detailed source deblending, allowing us fit spectral energy distributions in order estimate masses. show...
High-redshift dusty star-forming galaxies with very high star formation rates (500 -- 3000 M$_{\odot}$ yr$^{-1}$) are key to understanding the of most extreme in early Universe. Characterising gas reservoir these systems can reveal driving factor behind formation. Using molecular tracers like high-J CO lines, neutral carbon lines and dust continuum, we estimate density radiation field intensity their interstellar media. In this paper, present resolution ($\sim$0.4$^{\prime\prime}$)...
ABSTRACT We combine archival ALMA data targeting the Hubble Ultra Deep Field (HUDF) to produce deepest currently attainable 1-mm maps of this key region. Our map covers 4.2 arcmin2, with a beamsize 1.49 arcsec $\, {\times }\, 1.07\,$ at an effective frequency 243 GHz (1.23 mm). It reaches rms 4.6 μJy beam$^{-1}$, 1.5 arcmin2 below 9.0 beam−1, improvement ${\gt }\,$5 per cent (and up 50 in some regions) over best previous map. also make wider, shallower map, covering 25.4 arcmin2. detect 45...
The South Pole Telescope (SPT) has systematically identified 81 high-redshift, strongly gravitationally lensed, dusty star-forming galaxies (DSFGs) in a 2500 square degree cosmological mm-wave survey. We present the final spectroscopic redshift survey of this flux-limited ($S_{870\, \mathrm{\mu m}} > 25\, \mathrm{mJy}$) sample, initially selected at $1.4$ mm. was conducted with Atacama Large Millimeter/submillimeter Array across $3$ mm spectral window, targeting carbon monoxide line...
We present ALMA, NOEMA, and IRAM-30m/EMIR observations of the high-density tracer molecules HCN, HCO+, HNC in three brightest lensed dusty star-forming galaxies at z~3-3.5, part Planck's Dusty GEMS sample, to probe gas reservoirs closely associated with their exceptional levels star formation. obtain robust detections ten emission lines between J_up=4 6, as well several additional flux upper limits. In PLCK_G244.8+54.9, source z=3.0, HNC(5-4) line 0.1 resolution, together other...
Abstract With Σ SFR ∼ 4200 M ⊙ yr −1 kpc −2 , SPT 0346–52 ( z = 5.7) is the most intensely star-forming galaxy discovered by South Pole Telescope. In this paper, we expand on previous spatially resolved studies, using ALMA observations of dust continuum, [N ii ] 205 μ m, [C 158 [O i 146 and undetected 122 m 63 emission to study multiphase interstellar medium (ISM) in 0346–52. We use pixelated, visibility-based lens modeling reconstruct source-plane emission. also model photoionization code...