@article{15230,
  abstract     = {We have searched the Gaia DR2 catalog for previously unknown hot white dwarfs in the direction of young open star clusters. The aim of this experiment was to try and extend the initial–final mass relation (IFMR) to somewhat higher masses, potentially challenging the Chandrasekhar limit currently thought to be around 1.38 M⊙. We discovered a particularly interesting white dwarf in the direction of the young ∼150 Myr old cluster Messier 47 (NGC 2422). All Gaia indicators (proper motion, parallax, location in the Gaia color–magnitude diagram) suggest that it is a cluster member. Its spectrum, obtained from Gemini-South, yields a number of anomalies: it is a DB (helium-rich atmosphere) white dwarf, it has a large magnetic field (2.5 MG), is of high mass (∼1.06 M⊙), and its colors are very peculiar—particularly the redder ones (r, i, z and y), which suggests that it may have a late-type companion. This may be the only magnetized, detached binary white dwarf with a non-degenerate companion of any spectral type known in or out of a star cluster. If the white dwarf is a cluster member, as all indicators suggest, its progenitor had a mass just over 6 M⊙. It may, however, be telling an even more interesting story than the one related to the IFMR, one about the origin of stellar magnetic fields, SNe I, and gravitational waves from low-mass stellar systems.},
  author       = {Richer, Harvey B. and Kerr, Ronan and Heyl, Jeremy and Caiazzo, Ilaria and Cummings, Jeffrey and Bergeron, Pierre and Dufour, Patrick},
  issn         = {1538-4357},
  journal      = {The Astrophysical Journal},
  keywords     = {Space and Planetary Science, Astronomy and Astrophysics},
  number       = {2},
  publisher    = {American Astronomical Society},
  title        = {{A massive magnetic helium atmosphere white dwarf binary in a young star cluster}},
  doi          = {10.3847/1538-4357/ab2874},
  volume       = {880},
  year         = {2019},
}

@article{15231,
  abstract     = {In this paper, we analyze stellar proper motions in the core of the globular cluster 47 Tucanae to explore the possibility of an intermediate-mass black hole (IMBH) influence on the stellar dynamics. Our use of short-wavelength photometry affords us an exceedingly clear view of stellar motions into the very center of the crowded core, yielding proper motions for >50,000 stars in the central 2′. We model the velocity dispersion profile of the cluster using an isotropic Jeans model. The density distribution is taken as a central IMBH point mass added to a combination of King templates. We individually model the general low-mass cluster objects (main sequence/giant stars), as well as the concentrated populations of heavy binary systems and dark stellar remnants. Using unbinned likelihood model fitting, we find that the inclusion of the concentrated populations in our model plays a crucial role in fitting for an IMBH mass. The concentrated binaries and stellar-mass black holes (BHs) produce a sufficient velocity dispersion signal in the core so as to make an IMBH unnecessary to fit the observations. We additionally determine that a stellar-mass BH retention fraction of 8.5% becomes incompatible with our observed velocities in the core.},
  author       = {Mann, Christopher R. and Richer, Harvey and Heyl, Jeremy and Anderson, Jay and Kalirai, Jason and Caiazzo, Ilaria and Möhle, Swantje D. and Knee, Alan and Baumgardt, Holger},
  issn         = {1538-4357},
  journal      = {The Astrophysical Journal},
  keywords     = {Space and Planetary Science, Astronomy and Astrophysics},
  number       = {1},
  publisher    = {American Astronomical Society},
  title        = {{A multimass velocity dispersion model of 47 Tucanae indicates no evidence for an intermediate-mass black hole}},
  doi          = {10.3847/1538-4357/ab0e6d},
  volume       = {875},
  year         = {2019},
}

@article{17567,
  abstract     = {The growing number of stellar-mass binary black hole mergers discovered by Advanced LIGO and Advanced Virgo are starting to constrain the binaries' origin and environment. However, we still lack sufficiently accurate modeling of binary formation channels to obtain strong constraints, or to identify sub-populations. One promising formation mechanism that could result in different black hole properties is binaries merging within the accretion disks of Active Galactic Nuclei (AGN). Here we show that the black holes' orbital alignment with the AGN disks preferentially selects heavier black holes. We carry out Monte Carlo simulations of orbital alignment with AGN disks, and find that AGNs harden the initial black hole mass function. Assuming an initial power law mass distribution M−βbh, we find that the power law index changes by Δβ∼1.3, resulting in a more top-heavy population of merging black holes. This change is independent of the mass of, and accretion rate onto, the supermassive black hole in the center of the AGN. Our simulations predict an AGN-assisted merger rate of ∼4Gpc−3yr−1. With its hardened mass spectra, the AGN channel could be responsible for 10−50% of gravitational-wave detections.},
  author       = {Yang, Y. and Bartos, I. and Haiman, Zoltán and Kocsis, B. and Márka, Z. and Stone, N. C. and Márka, S.},
  issn         = {0004-637X},
  journal      = {The Astrophysical Journal},
  number       = {2},
  publisher    = {American Astronomical Society},
  title        = {{AGN disks harden the mass distribution of stellar-mass binary black hole mergers}},
  doi          = {10.3847/1538-4357/ab16e3},
  volume       = {876},
  year         = {2019},
}

@article{15234,
  abstract     = {Using parallaxes from Gaia Data Release 2 (Gaia DR2), we estimate the distance to the globular clusters 47 Tuc and NGC 362, taking advantage of the background stars in the Small Magellanic Cloud and quasars to account for various parallax systematics. We found the parallax to be dependent on the Gaia DR2 G-band apparent magnitude for stars with 13 < G < 18, where brighter stars have a lower parallax zero point than fainter stars. The distance to 47 Tuc was found to be 4.45 ± 0.01 ± 0.12 kpc, and for NGC 362 8.54 ± 0.20 ± 0.44 kpc, with random and systematic errors listed, respectively. This is the first time a precise distance measurement directly using parallaxes has been determined for either of these two globular clusters.},
  author       = {Chen, Seery and Richer, Harvey and Caiazzo, Ilaria and Heyl, Jeremy},
  issn         = {1538-4357},
  journal      = {The Astrophysical Journal},
  keywords     = {Space and Planetary Science, Astronomy and Astrophysics},
  number       = {2},
  publisher    = {American Astronomical Society},
  title        = {{Distances to the globular clusters 47 Tucanae and NGC 362 using Gaia DR2 parallaxes}},
  doi          = {10.3847/1538-4357/aae089},
  volume       = {867},
  year         = {2018},
}

@article{17575,
  abstract     = {Black hole (BH) mergers detectable with the Laser Interferometer Gravitational-wave Observatory (LIGO) can occur in active galactic nucleus (AGN) disks. Here we parameterize the merger rates, the mass spectrum, and the spin spectrum of BHs in AGN disks. The predicted merger rate spans ∼10−3–104 Gpc−1 yr−1, so upper limits from LIGO (<212 Gpc−1 yr−1) already constrain it. The predicted mass spectrum has the form of a broken power law, consisting of a pre-existing BH power-law mass spectrum and a harder power-law mass spectrum resulting from mergers. The predicted spin spectrum is multipeaked with the evolution of retrograde spin BHs in the gas disk playing a key role. We outline the large uncertainties in each of these LIGO observables for this channel and we discuss ways in which they can be constrained in the future.},
  author       = {McKernan, Barry and Saavik Ford, K. E. and Bellovary, J. and Leigh, N. W. C. and Haiman, Zoltán and Kocsis, B. and Lyra, W. and Mac Low, M.-M. and Metzger, B. and O’Dowd, M. and Endlich, S. and Rosen, D. J.},
  issn         = {0004-637X},
  journal      = {The Astrophysical Journal},
  number       = {1},
  publisher    = {American Astronomical Society},
  title        = {{Constraining stellar-mass black hole mergers in AGN disks detectable with LIGO}},
  doi          = {10.3847/1538-4357/aadae5},
  volume       = {866},
  year         = {2018},
}

@article{17680,
  abstract     = {The advent of time domain astronomy is revolutionizing our understanding of the universe. Programs such as the Catalina Real-time Transient Survey (CRTS) or the Palomar Transient Factory (PTF) surveyed millions of objects for several years, allowing variability studies on large statistical samples. The inspection of ≈250 k quasars in CRTS resulted in a catalog of 111 potentially periodic sources, put forward as supermassive black hole binary (SMBHB) candidates. A similar investigation on PTF data yielded 33 candidates from a sample of ≈35 k quasars. Working under the SMBHB hypothesis, we compute the implied SMBHB merger rate and we use it to construct the expected gravitational wave background (GWB) at nano-Hz frequencies, probed by pulsar timing arrays (PTAs). After correcting for incompleteness and assuming virial mass estimates, we find that the GWB implied by the CRTS sample exceeds the current most stringent PTA upper limits by almost an order of magnitude. After further correcting for the implicit bias in virial mass measurements, the implied GWB drops significantly but is still in tension with the most stringent PTA upper limits. Similar results hold for the PTF sample. Bayesian model selection shows that the null hypothesis (whereby the candidates are false positives) is preferred over the binary hypothesis at about 2.3σ and 3.6σ for the CRTS and PTF samples respectively. Although not decisive, our analysis highlights the potential of PTAs as astrophysical probes of individual SMBHB candidates and indicates that the CRTS and PTF samples are likely contaminated by several false positives.},
  author       = {Sesana, Alberto and Haiman, Zoltán and Kocsis, Bence and Kelley, Luke Zoltan},
  issn         = {0004-637X},
  journal      = {The Astrophysical Journal},
  number       = {1},
  publisher    = {American Astronomical Society},
  title        = {{Testing the binary hypothesis: Pulsar timing constraints on supermassive black hole binary candidates}},
  doi          = {10.3847/1538-4357/aaad0f},
  volume       = {856},
  year         = {2018},
}

@article{11518,
  abstract     = {We present spectroscopic follow-up observations of CR7 with ALMA, targeted at constraining the infrared (IR) continuum and [C II]158 mm line-emission at high spatial resolution matched to the HST/WFC3 imaging. CR7 is a luminous Lyα emitting galaxy at z = 6.6 that consists of three separated UV-continuum components. Our observations reveal several well-separated components of [C II] emission. The two most luminous components in [C II] coincide with the brightest UV components (A and B), blueshifted by »150 km s−1 with respect to the
peak of Lyα emission. Other [C II] components are observed close to UV clumps B and C and are blueshifted by »300 and ≈80 km s−1 with respect to the systemic redshift. We do not detect FIR continuum emission due to dust with a 3σ limiting luminosity LIR T L d 35 K 3.1 10 = <´ 10 ( ) . This allows us to mitigate uncertainties in the dust-corrected SFR and derive SFRs for the three UV clumps A, B, and C of 28, 5, and 7 M yr−1. All clumps have [C II] luminosities consistent within the scatter observed in the local relation between SFR and L[ ] C II , implying that strong Lyα emission does not necessarily anti-correlate with [C II] luminosity. Combining
our measurements with the literature, we show that galaxies with blue UV slopes have weaker [C II] emission at fixed SFR, potentially due to their lower metallicities and/or higher photoionization. Comparison with hydrodynamical simulations suggests that CR7ʼs clumps have metallicities of 0.1 Z Z 0.2 < < . The observed ISM structure of CR7 indicates that we are likely witnessing the build up of a central galaxy in the early universe through complex accretion of satellites.},
  author       = {Matthee, Jorryt J and Sobral, D. and Boone, F. and Röttgering, H. and Schaerer, D. and Girard, M. and Pallottini, A. and Vallini, L. and Ferrara, A. and Darvish, B. and Mobasher, B.},
  issn         = {1538-4357},
  journal      = {The Astrophysical Journal},
  keywords     = {Space and Planetary Science, Astronomy and Astrophysics, dark ages, reionization, first stars – galaxies: formation – galaxies: high-redshift – galaxies: ISM – galaxies: kinematics and dynamics},
  number       = {2},
  publisher    = {IOP Publishing},
  title        = {{ALMA reveals metals yet no dust within multiple components in CR7}},
  doi          = {10.3847/1538-4357/aa9931},
  volume       = {851},
  year         = {2017},
}

@article{15240,
  abstract     = {Multi-epoch observations with the Advanced Camera Survey and WFC3 on the Hubble Space Telescope provide a unique and comprehensive probe of stellar dynamics within 47 Tucanae. We confront analytic models of the globular cluster with the observed stellar proper motions that probe along the main sequence from just above 0.8–0.1M⊙ as well as white dwarfs younger than 1 Gyr. One field lies just beyond the half-light radius where dynamical models (e.g., lowered Maxwellian distributions) make robust predictions for the stellar proper motions. The observed proper motions in this outer field show evidence for anisotropy in the velocity distribution as well as skewness; the latter is evidence of rotation. The measured velocity dispersions and surface brightness distributions agree in detail with a rotating anisotropic model of the stellar distribution function with mild dependence of the proper-motion dispersion on mass. However, the best-fitting models underpredict the rotation and skewness of the stellar velocities. In the second field, centered on the core of the cluster, the mass segregation in proper motion is much stronger. Nevertheless the model developed in the outer field can be extended inward by taking this mass segregation into account in a heuristic fashion. The proper motions of the main-sequence stars yield a mass estimate of the cluster of 
 at a distance of 4.7 kpc. By comparing the proper motions of a sample of giant and subgiant stars with the observed radial velocities we estimate the distance to the cluster kinematically to be 4.29 ± 0.47 kpc.},
  author       = {Heyl, J. and Caiazzo, Ilaria and Richer, H. and Anderson, J. and Kalirai, J. and Parada, J.},
  issn         = {1538-4357},
  journal      = {The Astrophysical Journal},
  keywords     = {Space and Planetary Science, Astronomy and Astrophysics},
  number       = {2},
  publisher    = {American Astronomical Society},
  title        = {{Deep HST imaging in 47 Tucanae: A global dynamical model}},
  doi          = {10.3847/1538-4357/aa974f},
  volume       = {850},
  year         = {2017},
}

@article{17706,
  abstract     = {The Laser Interferometer Gravitational-Wave Observatory, LIGO, found direct evidence for double black hole binaries emitting gravitational waves. Galactic nuclei are expected to harbor the densest population of stellar-mass black holes. A significant fraction (∼30%) of these black holes can reside in binaries. We examine the fate of the black hole binaries in active galactic nuclei, which get trapped in the inner region of the accretion disk around the central supermassive black hole. We show that binary black holes can migrate into and then rapidly merge within the disk well within a Salpeter time. The binaries may also accrete a significant amount of gas from the disk, well above the Eddington rate. This could lead to detectable X-ray or gamma-ray emission, but would require hyper-Eddington accretion with a few percent radiative efficiency, comparable to thin disks. We discuss implications for gravitational wave observations and black hole population studies. We estimate that Advanced LIGO may detect ∼20 such, gas-induced binary mergers per year.},
  author       = {Bartos, Imre and Kocsis, Bence and Haiman, Zoltán and Márka, Szabolcs},
  issn         = {0004-637X},
  journal      = {The Astrophysical Journal},
  number       = {2},
  publisher    = {American Astronomical Society},
  title        = {{Rapid and bright stellar-mass binary black hole mergers in active galactic nuclei}},
  doi          = {10.3847/1538-4357/835/2/165},
  volume       = {835},
  year         = {2017},
}

@article{17618,
  abstract     = {The largest observed supermassive black holes (SMBHs) have a mass of M_BH ~ 10^{10} M_sun, nearly independent of redshift, from the local (z~0) to the early (z>6) Universe. We suggest that the growth of SMBHs above a few 10^{10} M_sun is prevented by small-scale accretion physics, independent of the properties of their host galaxies or of cosmology. Growing more massive BHs requires a gas supply rate from galactic scales onto a nuclear region as high as >10^3 M_sun/yr. At such a high accretion rate, most of the gas converts to stars at large radii (~10-100 pc), well before reaching the BH. We adopt a simple model (Thompson et al. 2005) for a star-forming accretion disk, and find that the accretion rate in the sub-pc nuclear region is reduced to the smaller value of at most a few M_sun/yr. This prevents SMBHs from growing above ~10^{11} M_sun in the age of the Universe. Furthermore, once a SMBH reaches a sufficiently high mass, this rate falls below the critical value at which the accretion flow becomes advection dominated. Once this transition occurs, BH feeding can be suppressed by strong outflows and jets from hot gas near the BH. We find that the maximum SMBH mass, given by this transition, is between M_{BH,max} ~ (1-6) * 10^{10} M_sun, depending primarily on the efficiency of angular momentum transfer inside the galactic disk, and not on other properties of the host galaxy.},
  author       = {Inayoshi, Kohei and Haiman, Zoltán},
  issn         = {0004-637X},
  journal      = {The Astrophysical Journal},
  number       = {2},
  publisher    = {American Astronomical Society},
  title        = {{Is there a maximum mass for black holes in galactic nuclei?}},
  doi          = {10.3847/0004-637x/828/2/110},
  volume       = {828},
  year         = {2016},
}

@article{11519,
  abstract     = {Faint Lyα emitters become increasingly rarer toward the reionization epoch (z ∼ 6–7). However, observations from a very large (∼5 deg2) Lyα narrow-band survey at z = 6.6 show that this is not the case for the most luminous emitters, capable of ionizing their own local bubbles. Here we present follow-up observations of the two most luminous Lyα candidates in the COSMOS field: “MASOSA” and “CR7.” We used X-SHOOTER, SINFONI, and FORS2 on the Very Large Telescope, and DEIMOS on Keck, to confirm both candidates beyond any doubt. We find redshifts of z = 6.541 and z = 6.604 for “MASOSA” and “CR7,” respectively. MASOSA has a strong detection in Lyα with a line width of 386 ± 30 km s−1 (FWHM) and with very high EW0 (>200 Å), but undetected in the continuum, implying very low stellar mass and a likely young, metal-poor stellar population. “CR7,” with an observed Lyα luminosity of 1043.92±0.05 erg s−1 is the most luminous Lyα emitter ever found at z > 6 and is spatially extended (∼16 kpc). “CR7” reveals a narrow Lyα line with 266 ± 15 km s−1 FWHM, being detected in the near-infrared (NIR) (rest-frame UV; β = −2.3 ± 0.1) and in IRAC/Spitzer. We detect a narrow He II 1640 Å emission line (6σ, FWHM = 130 ± 30 km s−1 ) in CR7 which can explain the clear excess seen in the J-band photometry (EW0 ∼ 80 Å). We find no other emission lines from the UV to the NIR in our X-SHOOTER spectra (He II/O III] 1663 Å > 3 and He II/C III] 1908 Å > 2.5). We conclude that CR7 is best explained by a combination of a PopIII-like population, which dominates the rest-frame UV and the nebular emission, and a more normal stellar population, which presumably dominates the mass. Hubble Space Telescope/WFC3 observations show that the light is indeed spatially separated between a very blue component, coincident with Lyα and He II emission, and two red components (∼5 kpc away), which dominate the mass. Our findings are consistent with theoretical predictions of a PopIII wave, with PopIII star formation migrating away from the original sites of star formation.},
  author       = {Sobral, David and Matthee, Jorryt J and Darvish, Behnam and Schaerer, Daniel and Mobasher, Bahram and Röttgering, Huub and Santos, Sérgio and Hemmati, Shoubaneh},
  issn         = {1538-4357},
  journal      = {The Astrophysical Journal},
  keywords     = {Space and Planetary Science, Astronomy and Astrophysics, dark ages, reionization, first stars – early universe – galaxies: evolution},
  number       = {2},
  pages        = {139},
  publisher    = {IOP Publishing},
  title        = {{Evidence for PopIII-like stellar populations in the most luminous Lyα emitters at the epoch of reionisation: Spectroscopic confirmation}},
  doi          = {10.1088/0004-637X/808/2/139},
  volume       = {808},
  year         = {2015},
}

@article{17620,
  abstract     = {We present the results of two-dimensional (2D) hydrodynamical simulations of circumbinary disk accretion using the finite-volume code DISCO. This code solves the 2D viscous Navier–Stokes equations on a high-resolution moving mesh which shears with the fluid flow, greatly reducing advection errors in comparison with a fixed grid. We perform a series of simulations for binary mass ratios in the range 0.026 ⩽ q ⩽ 1.0, each lasting longer than a viscous time so that we reach a quasi-steady accretion state. In each case, we find that gas is efficiently stripped from the inner edge of the circumbinary disk and enters the cavity along accretion streams, which feed persistent "mini disks" surrounding each black hole. We find that for q ≳ 0.1, the binary excites eccentricity in the inner region of the circumbinary disk, creating an overdense lump which gives rise to enhanced periodicity in the accretion rate. The dependence of the periodicity on mass ratio may provide a method for observationally inferring mass ratios from measurements of the accretion rate. We also find that for all mass ratios studied, the magnitude of the accretion onto the secondary is sufficient to drive the binary toward larger mass ratio. This suggests a mechanism for biasing mass-ratio distributions toward equal mass.},
  author       = {Farris, Brian D. and Duffell, Paul and MacFadyen, Andrew I. and Haiman, Zoltán},
  issn         = {0004-637X},
  journal      = {The Astrophysical Journal},
  number       = {2},
  publisher    = {American Astronomical Society},
  title        = {{Binary black hole accretion from a circumbinary disk: Gas dynamics inside the central cavity}},
  doi          = {10.1088/0004-637x/783/2/134},
  volume       = {783},
  year         = {2014},
}

@article{11520,
  abstract     = {We present the spatially resolved Hα dynamics of 16 star-forming galaxies at z ∼ 0.81 using the new KMOS multi-object integral field spectrograph on the ESO Very Large Telescope. These galaxies, selected using 1.18 μm narrowband imaging from the 10 deg2 CFHT-HiZELS survey of the SA 22 hr field, are found in a ∼4 Mpc overdensity of Hα emitters and likely reside in a group/intermediate environment, but not a cluster. We confirm and identify a rich group of star-forming galaxies at z = 0.813 ± 0.003, with 13 galaxies within 1000 km s−1 of each other, and seven within a diameter of 3 Mpc. All of our galaxies are “typical” star-forming galaxies at their redshift, 0.8 ± 0.4 SFR$^*_{z = 0.8}$, spanning a range of specific star formation rates (sSFRs) of 0.2–1.1 Gyr−1 and have a median metallicity very close to solar of 12 + log(O/H) = 8.62 ± 0.06. We measure the spatially resolved Hα dynamics of the galaxies in our sample and show that 13 out of 16 galaxies can be described by rotating disks and use the data to derive inclination corrected rotation speeds of 50–275 km s−1. The fraction of disks within our sample is 75% ± 8%, consistent with previous results based on Hubble Space Telescope morphologies of Hα-selected galaxies at z ∼ 1 and confirming that disks dominate the SFR density at z ∼ 1. Our Hα galaxies are well fitted by the z ∼ 1–2 Tully–Fisher (TF) relation, confirming the evolution seen in the zero point. Apart from having, on average, higher stellar masses and lower sSFRs, our group galaxies at z = 0.81 present the same mass–metallicity and TF relation as z ∼ 1 field galaxies and are all disk galaxies.},
  author       = {Sobral, D. and Swinbank, A. M. and Stott, J. P. and Matthee, Jorryt J and Bower, R. G. and Smail, Ian and Best, P. and Geach, J. E. and Sharples, R. M.},
  issn         = {1538-4357},
  journal      = {The Astrophysical Journal},
  keywords     = {Space and Planetary Science, Astronomy and Astrophysics, galaxies: evolution – galaxies, high-redshift – galaxies, starburst},
  number       = {2},
  publisher    = {IOP Publishing},
  title        = {{The dynamics of z=0.8 H-alpha-selected star-forming galaxies from KMOS/CF-HiZELS}},
  doi          = {10.1088/0004-637x/779/2/139},
  volume       = {779},
  year         = {2013},
}

@article{17657,
  abstract     = {We present observations of a luminous galaxy at z = 6.573—the end of the reionization epoch—which has been spectroscopically confirmed twice. The first spectroscopic confirmation comes from slitless Hubble Space Telescope Advanced Camera for Surveys grism spectra from the PEARS survey (Probing Evolution And Reionization Spectroscopically), which show a dramatic continuum break in the spectrum at rest frame 1216 Å. The second confirmation is done with Keck + DEIMOS. The continuum is not clearly detected with ground-based spectra, but high wavelength resolution enables the Lyα emission line profile to be determined. We compare the line profile to composite line profiles at z = 4.5. The Lyα line profile shows no signature of a damping wing attenuation, confirming that the intergalactic gas is ionized at z = 6.57. Spectra of Lyman breaks at yet higher redshifts will be possible using comparably deep observations with IR-sensitive grisms, even at redshifts where Lyα is too attenuated by the neutral intergalactic medium to be detectable using traditional spectroscopy from the ground.},
  author       = {Rhoads, James E. and Malhotra, Sangeeta and Stern, Daniel and Dickinson, Mark and Pirzkal, Norbert and Spinrad, Hyron and Reddy, Naveen and Hathi, Nimish and Grogin, Norman and Koekemoer, Anton and Peth, Michael A. and Cohen, Seth and Zheng, Zhenya and Budavari, Tamas and Ferreras, Ignacio and Gardner, Jonathan P. and Gronwall, Caryl and Haiman, Zoltán and Kümmel, Martin and Meurer, Gerhardt and Moustakas, Leonidas and Panagia, Nino and Pasquali, Anna and Sahu, Kailash and di Serego Alighieri, Sperello and Somerville, Rachel and Straughn, Amber and Walsh, Jeremy and Windhorst, Rogier and Xu, Chun and Yan, Haojing},
  issn         = {0004-637X},
  journal      = {The Astrophysical Journal},
  number       = {1},
  publisher    = {American Astronomical Society},
  title        = {{A Lyman break galaxy in the epoch of reionization from hubble space telescope grism spectroscopy}},
  doi          = {10.1088/0004-637x/773/1/32},
  volume       = {773},
  year         = {2013},
}

@article{17670,
  abstract     = {The statistics of peak counts in reconstructed shear maps contain information beyond the power spectrum, and can improve cosmological constraints from measurements of the power spectrum alone if systematic errors can be controlled. We study the effect of galaxy shape measurement errors on predicted cosmological constraints from the statistics of shear peak counts with the Large Synoptic Survey Telescope (LSST). We use the LSST image simulator in combination with cosmological N-body simulations to model realistic shear maps for different cosmological models. We include both galaxy shape noise and, for the first time, measurement errors on galaxy shapes. We find that the measurement errors considered have relatively little impact on the constraining power of shear peak counts for LSST.},
  author       = {Bard, D. and Kratochvil, J. M. and Chang, C. and May, M. and Kahn, S. M. and AlSayyad, Y. and Ahmad, Z. and Bankert, J. and Connolly, A. and Gibson, R. R. and Gilmore, K. and Grace, E. and Haiman, Zoltán and Hannel, M. and Huffenberger, K. M. and Jernigan, J. G. and Jones, L. and Krughoff, S. and Lorenz, S. and Marshall, S. and Meert, A. and Nagarajan, S. and Peng, E. and Peterson, J. and Rasmussen, A. P. and Shmakova, M. and Sylvestre, N. and Todd, N. and Young, M.},
  issn         = {0004-637X},
  journal      = {The Astrophysical Journal},
  number       = {1},
  publisher    = {American Astronomical Society},
  title        = {{Effect of measurement errors on predicted cosmological constraints from shear peak statistics with large synoptic survey telescope}},
  doi          = {10.1088/0004-637x/774/1/49},
  volume       = {774},
  year         = {2013},
}

@article{17639,
  abstract     = {It has been proposed that primordial gas in early dark matter halos, with virial temperatures above 10^4 K, can avoid fragmentation and undergo rapid collapse, possibly resulting in a supermassive black hole (SMBH). This requires the gas to avoid cooling and to remain at temperatures near T=10^4 K. We show that this condition can be satisfied in the presence of a sufficiently strong primordial magnetic field, which heats the collapsing gas via ambipolar diffusion. If the field has a strength above B = 3.6 (comoving) nG, the collapsing gas is kept warm (T=10^4K) until it reaches the critical density n_crit=10^3 cm^{-3} at which the roto-vibrational states of H_2 approach local thermodynamic equilibrium. H_2-cooling then remains inefficient, and the gas temperature stays near 10^4K, even as it continues to collapse to higher densities. The critical magnetic field strength required to permanently suppress H_2-cooling is somewhat higher than upper limit of approx. 2 nG from the cosmic microwave background (CMB). However, it can be realized in the rare (2-3)-sigma regions of the spatially fluctuating B-field; these regions contain a sufficient number of halos to account for the z=6 quasar BHs.},
  author       = {Sethi, Shiv and Haiman, Zoltán and Pandey, Kanhaiya},
  issn         = {0004-637X},
  journal      = {The Astrophysical Journal},
  number       = {1},
  pages        = {615--621},
  publisher    = {American Astronomical Society},
  title        = {{Supermassive black hole formation at high redshifts through a primordial magnetic field}},
  doi          = {10.1088/0004-637x/721/1/615},
  volume       = {721},
  year         = {2010},
}

@article{17695,
  abstract     = {Clusters of galaxies have been extensively used to determine cosmological parameters. A major difficulty in making the best use of Sunyaev–Zel'dovich (SZ) and X-ray observations of clusters for cosmology is that using X-ray observations it is difficult to measure the temperature distribution and therefore determine the density distribution in individual clusters of galaxies out to the virial radius. Observations with the new generation of SZ instruments are a promising alternative approach. We use clusters of galaxies drawn from high-resolution adaptive mesh refinement cosmological simulations to study how well we should be able to constrain the large-scale distribution of the intracluster gas (ICG) in individual massive relaxed clusters using AMiBA in its configuration with 13 1.2 m diameter dishes (AMiBA13) along with X-ray observations. We show that non-isothermal β models provide a good description of the ICG in our simulated relaxed clusters. We use simulated X-ray observations to estimate the quality of constraints on the distribution of gas density, and simulated SZ visibilities (AMiBA13 observations) for constraints on the large-scale temperature distribution of the ICG. We find that AMiBA13 visibilities should constrain the scale radius of the temperature distribution to about 50% accuracy. We conclude that the upgraded AMiBA, AMiBA13, should be a powerful instrument to constrain the large-scale distribution of the ICG.},
  author       = {Molnar, Sandor M. and Umetsu, Keiichi and Birkinshaw, Mark and Bryan, Greg and Haiman, Zoltán and Hearn, Nathan and Shang, Cien and Ho, Paul T. P. and Huang, Chih-Wei Locutus and Koch, Patrick M. and Victor Liao, Yu-Wei and Lin, Kai-Yang and Liu, Guo-Chin and Nishioka, Hiroaki and Wang, Fu-Cheng and Wu, Jiun-Huei Proty},
  issn         = {0004-637X},
  journal      = {The Astrophysical Journal},
  number       = {2},
  pages        = {1272--1285},
  publisher    = {American Astronomical Society},
  title        = {{Constraining intracluster gas models with AMiBA13}},
  doi          = {10.1088/0004-637x/723/2/1272},
  volume       = {723},
  year         = {2010},
}

@article{17719,
  abstract     = {We propose to use a simple observable, the fractional area of "hot spots" in weak gravitational lensing mass maps, which are detected with high significance, to determine background cosmological parameters. Because these high-convergence regions are directly related to the physical nonlinear structures of the universe, they derive cosmological information mainly from the nonlinear regime of density fluctuations. We show that in combination with future cosmic microwave background anisotropy measurements, this method can place constraints on cosmological parameters that are comparable to those from the redshift distribution of galaxy cluster abundances. The main advantage of the statistic proposed in this paper is that projection effects, normally the main source of uncertainty when determining the presence and the mass of a galaxy cluster, here serve as a source of information.},
  author       = {Wang, Sheng and Haiman, Zoltán and May, Morgan},
  issn         = {0004-637X},
  journal      = {The Astrophysical Journal},
  number       = {1},
  pages        = {547--559},
  publisher    = {American Astronomical Society},
  title        = {{Constraining cosmology with high-convergence regions in weak lensing surveys}},
  doi          = {10.1088/0004-637x/691/1/547},
  volume       = {691},
  year         = {2009},
}

@article{17735,
  abstract     = {The supermassive black holes (SMBHs) massive enough to power the bright redshift ~6 quasars observed in the Sloan Digital Sky Survey (SDSS) are thought to have assembled by mergers and/or gas accretion from less massive "seed" BHs. If the seeds are the ~100 Msol remnant BHs from the first generation of stars, they must be in place well before redshift z=6, and must avoid being ejected from their parent proto-galaxies by the large (few hundred km/s) kicks they suffer from gravitational-radiation induced recoil during mergers with other BHs. We simulate the SMBH mass function at redshift z=6 using dark matter (DM) halo merger trees, coupled with a prescription for the halo occupation fraction, accretion histories, and radial recoil trajectories of the growing BHs. Our purpose is (i) to map out plausible scenarios for successful assembly of the z~6 quasar BHs by exploring a wide region of parameter space, and (ii) to predict the rate of low-frequency gravitational wave events detectable by the Laser Interferometer Space Antenna (LISA) for each such scenario. Our main findings are as follows: (1) ~100 Msol seed BHs can grow into the SDSS quasar BHs without super--Eddington accretion, but only if they form in minihalos by z~30 and subsequently accrete ~60% of the time; (2) the scenarios with optimistic assumptions required to explain the SDSS quasar BHs overproduce the mass density in lower--mass (10^5 to 10^7 Msol) SMBHs by a factor of 100-1000, unless seeds stop forming, or accrete at a severely diminished rates or duty cycles (e.g. due to feedback), at z < 20-30. We also present several successful assembly models and their LISA detection rates, including a "maximal" model that gives the highest rate (~30/yr at z~6) without overproducing the total SMBH density.},
  author       = {Tanaka, Takamitsu and Haiman, Zoltán},
  issn         = {0004-637X},
  journal      = {The Astrophysical Journal},
  number       = {2},
  pages        = {1798--1822},
  publisher    = {American Astronomical Society},
  title        = {{The assembly of supermassive black holes at high redshifts}},
  doi          = {10.1088/0004-637x/696/2/1798},
  volume       = {696},
  year         = {2009},
}

@article{17771,
  abstract     = {Cold dark matter (CDM) hierarchical structure formation models predict the existence of large-scale accretion shocks between the virial and turnaround radii of clusters of galaxies. Kocsis et al. suggest that the Sunyaev–Zel'dovich signal associated with such shocks might be observable with the next generation radio interferometer, ALMA (Atacama Large Millimeter Array). We study the three-dimensional distribution of accretion shocks around individual clusters of galaxies drawn from adaptive mesh refinement (AMR) and smoothed particle hydrodynamics simulations of ΛCDM (dark energy dominated CDM) models. In relaxed clusters, we find two distinct sets of shocks. One set ("virial shocks"), with Mach numbers of 2.5–4, is located at radii 0.9–1.3 Rvir, where Rvir is the spherical infall estimate of the virial radius, covering about 40%–50% of the total surface area around clusters at these radii. Another set of stronger shocks ("external shocks") is located farther out, at about 3 Rvir, with large Mach numbers (≈100), covering about 40%–60% of the surface area. We simulate SZ surface brightness maps of relaxed massive galaxy clusters drawn from high-resolution AMR runs, and conclude that ALMA should be capable of detecting the virial shocks in massive clusters of galaxies. More simulations are needed to improve estimates of astrophysical noise and to determine optimal observational strategies.},
  author       = {Molnar, Sandor M. and Hearn, Nathan and Haiman, Zoltán and Bryan, Greg and Evrard, August E. and Lake, George},
  issn         = {0004-637X},
  journal      = {The Astrophysical Journal},
  number       = {2},
  pages        = {1640--1656},
  publisher    = {American Astronomical Society},
  title        = {{Accretion shocks in clusters of galaxies and their SZ signature from cosmological simulations}},
  doi          = {10.1088/0004-637x/696/2/1640},
  volume       = {696},
  year         = {2009},
}