Publications (38)
The Murchison Widefield Array 21 cm Power Spectrum Analysis Methodology
Daniel C. Jacobs, B. J. Hazelton, C. M. Trott +61
We present the 21 cm power spectrum analysis approach of the Murchison Widefield Array Epoch of Reionization project. In this paper, we compare the outputs of multiple pipelines fo…
Massive Black Holes Across Cosmic Time
P. Madau, T. Abel, P. Bender +12
This White Paper to the National Academy of Sciences Astro2010 Decadal Review Committee outlines some of the outstanding questions regarding the assembly history of Massive Black H…
The Birth of a Relativistic Outflow in the Unusual γ-ray Transient Swift J164449.3+573451
B. A. Zauderer, E. Berger, A. M. Soderberg +24
Active galactic nuclei (AGN), powered by long-term accretion onto central supermassive black holes, produce relativistic jets with lifetimes of greater than one million yr that pre…
Large scale distribution of total mass versus luminous matter from Baryon Acoustic Oscillations: First search in the SDSS-III BOSS Data Release 10
M. T. Soumagnac, R. Barkana, C. G. Sabiu +5
Baryon Acoustic Oscillations (BAOs) in the early Universe are predicted to leave an as yet undetected signature on the relative clustering of total mass versus luminous matter. A d…
The low-frequency environment of the Murchison Widefield Array: radio-frequency interference analysis and mitigation
A. R. Offringa, R. B. Wayth, N. Hurley-Walker +62
The Murchison Widefield Array (MWA) is a new low-frequency interferometric radio telescope built in Western Australia at one of the locations of the future Square Kilometre Array (…
HerMES: ALMA Imaging of Herschel-selected Dusty Star-forming Galaxies
R. S. Bussmann, D. Riechers, A. Fialkov +25
The Herschel Multi-tiered Extragalactic Survey (HerMES) has identified large numbers of dusty star-forming galaxies (DSFGs) over a wide range in redshift. A detailed understanding…
Evidence for a Black Hole Remnant in the Type IIL Supernova 1979C
D. J. Patnaude, A. Loeb, C. Jones
We present an analysis of archival X-ray observations of the Type IIL supernova SN 1979C. We find that its X-ray luminosity is remarkably constant at (6.5+/-0.1) x 10^38 erg/s over…
Foregrounds in Wide-Field Redshifted 21 cm Power Spectra
Nithyanandan Thyagarajan, Daniel C. Jacobs, Judd D. Bowman +61
Detection of 21~cm emission of HI from the epoch of reionization, at redshifts z>6, is limited primarily by foreground emission. We investigate the signatures of wide-field measure…
On Poynting-Flux-Driven Bubbles and Shocks Around Merging Neutron Star Binaries
M. V. Medvedev, A. Loeb
Merging binaries of compact relativistic objects (neutron stars and black holes) are thought to be progenitors of short gamma-ray bursts and sources of gravitational waves, hence t…
Chandra High resolution Observations of CID-42, a candidate recoiling SMBH
F. Civano, M. Elvis, G. Lanzuisi +15
We present Chandra High Resolution Camera observations of CID-42, a candidate recoiling supermassive black hole (SMBH) at z=0.359 in the COSMOS survey. CID-42 shows two optical com…
The Galactic Center: A Laboratory for Fundamental Astrophysics and Galactic Nuclei
A. Ghez, M. Morris, J. Lu +24
As the closest example of a galactic nucleus, the Galactic center presents an exquisite laboratory for learning about supermassive black holes (SMBH) and their environs. Detailed s…
Probing the First Stars and Black Holes in the Early Universe with the Dark Ages Radio Explorer (DARE)
Jack O. Burns, T. J. W. Lazio, S. D. Bale +7
A concept for a new space-based cosmology mission called the Dark Ages Radio Explore (DARE) is presented in this paper. DARE's science objectives include (1) When did the first sta…
First Season MWA EoR Power Spectrum Results at Redshift 7
A. P. Beardsley, B. J. Hazelton, I. S. Sullivan +63
The Murchison Widefield Array (MWA) has collected hundreds of hours of Epoch of Reionization (EoR) data and now faces the challenge of overcoming foreground and systematic contamin…
Rotation and Internal Structure of Population III Protostars
A. Stacy, T. H. Greif, R. S. Klessen +2
We analyze the cosmological simulations performed in the recent work of Greif et al. (2012), which followed the early growth and merger history of Pop III stars while resolving sca…
Ejection of Fragments in Supernova Explosions
A. Loeb, F. A. Rasio, J. Shaham
Recent observations by the ROSAT X-ray satellite of the Vela supernova remnant have revealed, in addition to the previously identified compact nebula, a nearly circular emitting re…
Parametrising Epoch of Reionization foregrounds: A deep survey of low-frequency point-source spectra with the MWA
A. R. Offringa, C. M. Trott, N. Hurley-Walker +38
Experiments that pursue detection of signals from the Epoch of Reionization (EoR) are relying on spectral smoothness of source spectra at low frequencies. This article empirically…
Delay Spectrum with Phase-Tracking Arrays: Extracting the HI power spectrum from the Epoch of Reionization
Sourabh Paul, Shiv K. Sethi, Miguel F. Morales +51
The Detection of redshifted 21 cm emission from the epoch of reionization (EoR) is a challenging task owing to strong foregrounds that dominate the signal. In this paper, we propos…
Low frequency observations of linearly polarized structures in the interstellar medium near the south Galactic pole
Emil Lenc, B. M. Gaensler, X. H. Sun +76
We present deep polarimetric observations at 154 MHz with the Murchison Widefield Array (MWA), covering 625 deg^2 centered on RA=0 h, Dec=-27 deg. The sensitivity available in our…
SDSS J1152+0248: An eclipsing double white dwarf from the Kepler K2 campaign
N. Hallakoun, D. Maoz, M. Kilic +13
We report the discovery of the sixth known eclipsing double white dwarf (WD) system, SDSS J1152+0248, with a 2.3968 +/- 0.0003 h orbital period, in data from the Kepler Mission's K…
Collapse of Primordial Gas Clouds and the Formation of Quasar Black Holes
A. Loeb, F. A. Rasio
The formation of quasar black holes during the hydrodynamic collapse of protogalactic gas clouds is discussed. The dissipational collapse and long- term dynamical evolution of thes…
Dynamics of Astrophysical Bubbles and Bubble-Driven Shocks: Basic Theory, Analytical Solutions and Observational Signatures
M. V. Medvedev, A. Loeb
Bubbles in the interstellar medium are produced by astrophysical sources, which continuously or explosively deposit large amount of energy into the ambient medium. These expanding…
Cosmological Recombination of Lithium and its Effect on the Microwave Background Anisotropies
P. C. Stancil, A. Loeb, M. Zaldarriaga +2
The cosmological recombination history of lithium, produced during Big--Bang nucleosynthesis, is presented using updated chemistry and cosmological parameters consistent with recen…
Escape Fraction of Ionizing Radiation from Starburst Galaxies at High Redshifts
A. Ferrara, A. Loeb
Recent data indicates that the cosmic UV emissivity decreased with decreasing redshift z near the end of reionization. Lacking evidence for very massive early stars, this could sig…
A High Reliability Survey of Discrete Epoch of Reionization Foreground Sources in the MWA EoR0 Field
P. A. Carroll, J. Line, M. F. Morales +61
Detection of the Epoch of Reionization HI signal requires a precise understanding of the intervening galaxies and AGN, both for instrumental calibration and foreground removal. We…
Low frequency radio astronomy from the moon: cosmic reionization and more
C. L. Carilli, J. N. Hewitt, A. Loeb
We discuss low frequency radio astronomy from the moon, predominantly in the context of studying the neutral intergalactic medium during cosmic reionization using the HI 21cm line…
Chemical Classification of Spherules Recovered From The Pacific Ocean Site of The CNEOS 2014-01-08 (IM1) Bolide
A. Loeb, S. B. Jacobsen, R. Tagle +28
We have conducted an extensive towed-magnetic-sled survey during the period of June 14-28, 2023, over the seafloor about 85 km north of Manus Island, Papua New Guinea, centered aro…
A Runaway Black Hole in COSMOS: Gravitational Wave or Slingshot Recoil?
F. Civano, M. Elvis, G. Lanzuisi +39
We present a detailed study of a peculiar source in the COSMOS survey at z=0.359. Source CXOCJ100043.1+020637 (CID-42) presents two compact optical sources embedded in the same gal…
Resolving Gamma-Ray Burst 000301C with a Gravitational Microlens
P. M. Garnavich, A. Loeb, K. Z. Stanek
The afterglow of the Gamma-Ray Burst (GRB) 000301C exhibited achromatic, short time-scale variability that is difficult to reconcile with the standard relativistic shock model. We…
Confirmation of Wide-Field Signatures in Redshifted 21 cm Power Spectra
Nithyanandan Thyagarajan, Daniel C. Jacobs, Judd D. Bowman +52
We confirm our recent prediction of the "pitchfork" foreground signature in power spectra of high-redshift 21 cm measurements where the interferometer is sensitive to large-scale s…
Spectral energy distribution and radio halo of NGC 253 at low radio frequencies
A. D. Kapinska, L. Staveley-Smith, R. Crocker +67
We present new radio continuum observations of NGC253 from the Murchison Widefield Array at frequencies between 76 and 227 MHz. We model the broadband radio spectral energy distrib…
First constraints on Fuzzy Dark Matter from the dynamics of stellar streams in the Milky Way
Nicola C. Amorisco, A. Loeb
We present a novel method to constrain the mass of ultra-light bosons as the dark matter using stellar streams formed by disrupting Globular Clusters in the Milky Way. The turbulen…
Empirical Covariance Modeling for 21 cm Power Spectrum Estimation: A Method Demonstration and New Limits from Early Murchison Widefield Array 128-Tile Data
Joshua S. Dillon, Abraham R. Neben, Jacqueline N. Hewitt +52
The separation of the faint cosmological background signal from bright astrophysical foregrounds remains one of the most daunting challenges of mapping the high-redshift intergalac…
Stellar black holes at the dawn of the universe
I. F. Mirabel, M. Dijkstra, P. Laurent +2
It is well established that between 380000 and 1 billion years after the Big Bang the Inter Galactic Medium (IGM) underwent a "phase transformation" from cold and fully neutral to…
First Limits on the 21 cm Power Spectrum during the Epoch of X-ray heating
A. Ewall-Wice, Joshua S. Dillon, J. N. Hewitt +62
We present first results from radio observations with the Murchison Widefield Array seeking to constrain the power spectrum of 21 cm brightness temperature fluctuations between the…
CHIPS: The Cosmological HI Power Spectrum Estimator
Cathryn M. Trott, Bart Pindor, Pietro Procopio +49
Detection of the cosmological neutral hydrogen signal from the Epoch of Reionization, and estimation of its basic physical parameters, is the principal scientific aim of many curre…
Early Cosmic Formation of Massive Black Holes
M. Umemura, A. Loeb, E. L. Turner
The evolution of nonlinear density fluctuations around the Jeans mass shortly after cosmological recombination is analyzed using a 3D hydrodynamics/dark--matter code. The Cosmic Ba…
The Importance of Wide-field Foreground Removal for 21 cm Cosmology: A Demonstration With Early MWA Epoch of Reionization Observations
J. C. Pober, B. J. Hazelton, A. P. Beardsley +66
In this paper we present observations, simulations, and analysis demonstrating the direct connection between the location of foreground emission on the sky and its location in cosm…
Ultra-diffuse galaxies: the high-spin tail of the abundant dwarf galaxy population
N. C. Amorisco, A. Loeb
Recent observations have revealed the existence of an abundant population of faint, low surface brightness (SB) galaxies, which appear to be numerous and ubiquitous in nearby galax…