Search Publications
Suzaku reveals X-ray continuum piercing the nuclear absorber in Markarian 231
Maiolino, R.; Fiore, F.; Piconcelli, E. +3 more
We report the results from a 2011 Suzaku observation of the nearby low-ionization broad absorption line (BAL) quasar/ULIRG Markarian 231 (Mrk 231). These data reveal that the X-ray spectrum has undergone a large variation from the 2001 XMM-Newton and BeppoSAX observations. We interpret this finding according to a scenario whereby the X-ray continu…
On the nature of the brightest globular cluster in M81
Bressan, A.; Torres-Papaqui, J. P.; Mayya, Y. D. +5 more
We analyse the photometric, chemical, star formation history and structural properties of the brightest globular cluster (GC) in M81, referred to as GC1 in this work, with the intention of establishing its nature and origin. We find that it is a metal-rich ([Fe/H] = -0.60 ± 0.10), alpha-enhanced ([α/Fe] ∼ 0.20 ± 0.05), core-collapsed (core radius …
Helioseismic Investigation of Emerging Magnetic Flux in the Solar Convection Zone
Zhao, Junwei; Ilonidis, Stathis; Hartlep, Thomas
Helioseismology is capable of detecting signatures of emerging sunspot regions in the solar interior before they appear at the surface. Here we present measurements that show the rising motion of the acoustic travel-time perturbation signatures in the deep convection zone, and study the possible physical origin of these signatures using observatio…
Distribution of Magnetic Helicity Flux with Solar Cycles
Zhang, Hongqi; Yang, Shangbin
It is normally believed that a magnetic field transfers helicity from the solar subatmosphere into interplanetary space. This is based on the calculation of the injected magnetic helicity near the center of the solar disk between latitude ±30° of both solar hemispheres in the period 1996-2009. As one follows the long-term injection of magnetic hel…
Three-dimensional Keplerian orbit-superposition models of the nucleus of M31
Magorrian, J.; Brown, C. K.
We present three-dimensional eccentric disc models of the nucleus of M31, modelling the disc as a linear combination of thick rings of massless stars orbiting in the potential of a central black hole. Our models are non-parametric generalizations of the parametric models of Peiris and Tremaine. The models reproduce well the observed Wide Field Pla…
Supersoft X-rays reveal a classical nova in the M 31 globular cluster Bol 126
Della Valle, M.; Pietsch, W.; Haberl, F. +17 more
Context. Classical novae (CNe) represent the main class of supersoft X-ray sources (SSSs) in the central region of our neighbouring galaxy M 31. Only three confirmed novae and three SSSs have been discovered in globular clusters (GCs) of any galaxy so far, of which one nova and two SSSs (including the nova) were found in M 31 GCs.
Aims: To st…
The IMACS Cluster Building Survey. V. Further Evidence for Starburst Recycling from Quantitative Galaxy Morphologies
Dressler, Alan; Vulcani, Benedetta; Gladders, Michael D. +5 more
Using J- and K s-band imaging obtained as part of the IMACS Cluster Building Survey (ICBS), we measure Sérsic indices for 2160 field and cluster galaxies at 0.31 < z < 0.54. Using both mass- and magnitude-limited samples, we compare the distributions for spectroscopically determined passive, continuously star-forming, starburst, a…
Probing the Inner Regions of Protoplanetary Disks with CO Absorption Line Spectroscopy
Herczeg, Gregory J.; Brown, Alexander; France, Kevin +4 more
Carbon monoxide (CO) is the most commonly used tracer of molecular gas in the inner regions of protoplanetary disks. CO can be used to constrain the excitation and structure of the circumstellar environment. Absorption line spectroscopy provides an accurate assessment of a single line of sight through the protoplanetary disk system, giving more st…
Planck intermediate results. VI. The dynamical structure of PLCKG214.6+37.0, a Planck discovered triple system of galaxy clusters
Böhringer, H.; Kneissl, R.; Dahle, H. +206 more
The survey of galaxy clusters performed by Planck through the Sunyaev-Zeldovich effect has already discovered many interesting objects, thanks to its full sky coverage. One of the SZ candidates detected inthe early months of the mission near to the signal-to-noise threshold, PLCKG214.6+37.0, was later revealed by XMM-Newton to be a triple system o…
HD 85567: A Herbig B[e] star or an interacting B[e] binary?. Resolving HD 85567's circumstellar environment with the VLTI and AMBER
Weigelt, G.; Caratti o Garatti, A.; Wheelwright, H. E. +1 more
Context.
Aims: To elucidate the…