Search Publications
Linking black hole growth with host galaxies: the accretion-stellar mass relation and its cosmic evolution
Brandt, W. N.; Vignali, C.; Xue, Y. Q. +9 more
Previous studies suggest that the growth of supermassive black holes (SMBHs) may be fundamentally related to host-galaxy stellar mass (M⋆). To investigate this SMBH growth-M⋆ relation in detail, we calculate long-term SMBH accretion rate as a function of M⋆ and redshift [\overlineBHAR(M_{\star }, z)] over ranges of…
Transient spiral structure and the disc velocity substructure in Gaia DR2
Bovy, Jo; Grand, Robert J. J.; Kawata, Daisuke +2 more
The second data release from ESA's Gaia mission has revealed many ridge-like structures in the velocity distribution of the Milky Way. We show that these can arise naturally from winding transient spiral structure that is commonly seen in N-body simulations of disc galaxies. We construct test particle models of the winding spiral structure, and co…
ASASSN-18ey: The Rise of a New Black Hole X-Ray Binary
Kochanek, C. S.; Rest, A.; Stalder, B. +24 more
We present the discovery of ASASSN-18ey (MAXI J1820+070), a new black hole low-mass X-ray binary (LMXB) discovered by the All-Sky Automated Survey for SuperNovae (ASAS-SN). A week after ASAS-SN discovered ASASSN-18ey as an optical transient, it was detected as an X-ray transient by MAXI/GCS. Here, we analyze ASAS-SN and Asteroid Terrestrial-impact…
Genesis and Impulsive Evolution of the 2017 September 10 Coronal Mass Ejection
Veronig, Astrid M.; Temmer, Manuela; Dissauer, Karin +7 more
The X8.2 event of 2017 September 10 provides unique observations to study the genesis, magnetic morphology, and impulsive dynamics of a very fast coronal mass ejection (CME). Combining GOES-16/SUVI and SDO/AIA EUV imagery, we identify a hot (T ≈ 10-15 MK) bright rim around a quickly expanding cavity, embedded inside a much larger CME shell (T ≈ 1-…
Dust models compatible with Planck intensity and polarization data in translucent lines of sight
Miville-Deschênes, M. -A.; Boulanger, F.; Levrier, F. +6 more
Context. Current dust models are challenged by the dust properties inferred from the analysis of Planck observations in total and polarized emission.
Aims: We propose new dust models compatible with polarized and unpolarized data in extinction and emission for translucent lines of sight (0.5 < AV < 2.5).
Methods: We amen…
Atomic data and spectral modeling constraints from high-resolution X-ray observations of the Perseus cluster with Hitomi
Done, Chris; Safi-Harb, Samar; Hamaguchi, Kenji +192 more
The Hitomi Soft X-ray Spectrometer spectrum of the Perseus cluster, with ∼5 eV resolution in the 2-9 keV band, offers an unprecedented benchmark of the atomic modeling and database for hot collisional plasmas. It reveals both successes and challenges of the current atomic data and models. The latest versions of AtomDB/APEC (3.0.8), SPEX (3.03.00),…
The Faint End of the z = 5 Quasar Luminosity Function from the CFHTLS
Fan, Xiaohui; Jiang, Linhua; McGreer, Ian D. +1 more
We present results from a spectroscopic survey of z ∼ 5 quasars in the CFHT Legacy Survey. Using both optical color selection and a likelihood method, we select 97 candidates over an area of 105 deg2 to a limit of i AB < 23.2, and 7 candidates in the range 23.2 < i AB < 23.7 over an area of 18.5 deg2<…
Partial Variance of Increments Method in Solar Wind Observations and Plasma Simulations
Perri, S.; Matthaeus, W. H.; Wan, M. +4 more
The method called "PVI" (Partial Variance of Increments) has been increasingly used in analysis of spacecraft and numerical simulation data since its inception in 2008. The purpose of the method is to study the kinematics and formation of coherent structures in space plasmas, a topic that has gained considerable attention, leading the development …
Forming Super Star Clusters in the Central Starburst of NGC 253
Meier, David S.; Ott, Jürgen; Bolatto, Alberto D. +12 more
NGC 253 hosts the nearest nuclear starburst. Previous observations show a region rich in molecular gas, with dense clouds associated with recent star formation. We used the Atacama Large Submillimeter/Millimeter Array (ALMA) to image the 350 GHz dust continuum and molecular line emission from this region at 2 pc resolution. Our observations reveal…
The KMOS Redshift One Spectroscopic Survey (KROSS): the origin of disc turbulence in z ≈ 1 star-forming galaxies
Smail, Ian; Konstantopoulos, I. S.; Federrath, C. +27 more
We analyse the velocity dispersion properties of 472 z ∼ 0.9 star-forming galaxies observed as part of the KMOS Redshift One Spectroscopic Survey (KROSS). The majority of this sample is rotationally dominated (83 ± 5 per cent with vC/σ0 > 1) but also dynamically hot and highly turbulent. After correcting for beam smearing …