Search Publications

Nonlinear Force-Free Extrapolation of Emerging Flux with a Global Twist and Serpentine Fine Structures
DOI: 10.1007/s11207-011-9865-8 Bibcode: 2012SoPh..278...73V

van Driel-Gesztelyi, L.; Démoulin, P.; Baker, D. +5 more

We study the flux emergence process in NOAA active region 11024, between 29 June and 7 July 2009, by means of multi-wavelength observations and nonlinear force-free extrapolation. The main aim is to extend previous investigations by combining, as much as possible, high spatial resolution observations to test our present understanding of small-scal…

2012 Solar Physics
Hinode SOHO 69
A 10 kpc Scale Seyfert Galaxy Outflow: HST/COS Observations of IRAS F22456-5125
DOI: 10.1088/0004-637X/751/2/107 Bibcode: 2012ApJ...751..107B

Kriss, Gerard A.; Arav, Nahum; Edmonds, Doug +2 more

We present analysis of the UV spectrum of the low-z AGN IRAS F22456-5125 obtained with the Cosmic Origins Spectrograph on board the Hubble Space Telescope. The spectrum reveals six main kinematic components, spanning a range of velocities of up to 800 km s-1, which for the first time are observed in troughs associated with C II, C IV, N…

2012 The Astrophysical Journal
eHST 69
The complete far-infrared and submillimeter spectrum of the Class 0 protostar Serpens SMM1 obtained with Herschel. Characterizing UV-irradiated shocks heating and chemistry
DOI: 10.1051/0004-6361/201219912 Bibcode: 2012A&A...548A..77G

van Dishoeck, E. F.; Cernicharo, J.; Goicoechea, J. R. +8 more

We present the first complete ~55-671 µm spectral scan of a low-mass Class 0 protostar (Serpens SMM1) taken with the PACS and SPIRE spectrometers onboard Herschel. More than 145 lines have been detected, most of them rotationally excited lines of 12CO (full ladder from Ju = 4-3 to 42-41 and Eu/k = 4971 K), H<…

2012 Astronomy and Astrophysics
Herschel 69
A Non-radial Eruption in a Quadrupolar Magnetic Configuration with a Coronal Null
DOI: 10.1088/0004-637X/757/2/149 Bibcode: 2012ApJ...757..149S

Liu, Yang; Hayashi, Keiji; Sun, Xudong +2 more

We report one of the several homologous non-radial eruptions from NOAA active region (AR) 11158 that are strongly modulated by the local magnetic field as observed with the Solar Dynamic Observatory. A small bipole emerged in the sunspot complex and subsequently created a quadrupolar flux system. Nonlinear force-free field extrapolation from vecto…

2012 The Astrophysical Journal
Hinode 69
Luminosity and mass functions of the three main sequences of the globular cluster NGC 2808
DOI: 10.1051/0004-6361/201116539 Bibcode: 2012A&A...537A..77M

Anderson, J.; Milone, A. P.; Marino, A. F. +5 more

High-precision HST photometry has revealed that the globular cluster (GC) NGC 2808 hosts a triple main sequence (MS) corresponding to three stellar populations with different helium abundances. We carried out photometry on ACS/WFC HST images of NGC 2808 with the main purpose of measuring the luminosity function (LF) of stars in the three different…

2012 Astronomy and Astrophysics
eHST 69
CLASH: New Multiple Images Constraining the Inner Mass Profile of MACS J1206.2-0847
DOI: 10.1088/0004-637X/749/2/97 Bibcode: 2012ApJ...749...97Z

Infante, L.; Zheng, W.; Molino, A. +45 more

We present a strong-lensing analysis of the galaxy cluster MACS J1206.2-0847 (z = 0.44) using UV, Optical, and IR, HST/ACS/WFC3 data taken as part of the CLASH multi-cycle treasury program, with VLT/VIMOS spectroscopy for some of the multiply lensed arcs. The CLASH observations, combined with our mass model, allow us to identify 47 new multiply le…

2012 The Astrophysical Journal
eHST 69
The Nature of Extremely Red H - [4.5] > 4 Galaxies Revealed with SEDS and CANDELS
DOI: 10.1088/2041-8205/750/1/L20 Bibcode: 2012ApJ...750L..20C

Dickinson, M.; Ferguson, H. C.; Giavalisco, M. +20 more

We have analyzed a sample of 25 extremely red H - [4.5] > 4 galaxies, selected using 4.5 µm data from the Spitzer SEDS survey and deep H-band data from the Hubble Space Telescope CANDELS survey, over ~180 arcmin2 of the UKIDSS Ultra-Deep Survey field. Our aim is to investigate the nature of this rare population of mid-infrared …

2012 The Astrophysical Journal
eHST 69
Testing the universality of star formation - I. Multiplicity in nearby star-forming regions
DOI: 10.1111/j.1365-2966.2012.20437.x Bibcode: 2012MNRAS.421.2025K

Patience, Jenny; Parker, Richard J.; King, Robert R. +1 more

We have collated multiplicity data for five clusters (Taurus, Chamaeleon I, Ophiuchus, IC 348 and the Orion Nebula Cluster). We have applied the same mass ratio (flux ratios of ΔK≤ 2.5) and primary mass cuts (∼0.1-3.0 M) to each cluster and therefore have directly comparable binary statistics for all five clusters in the separation ran…

2012 Monthly Notices of the Royal Astronomical Society
eHST 68
The MeV spectral tail in Cyg X-1 and optically thin emission of jets
DOI: 10.1111/j.1365-2966.2012.20903.x Bibcode: 2012MNRAS.423..663Z

Zdziarski, Andrzej A.; Sikora, Marek; Lubiński, Piotr

We study the average X-ray and soft γ-ray spectrum of Cyg X-1 in the hard spectral state, using data from INTEGRAL. We compare these results with those from CGRO, and find a good agreement. Confirming previous studies, we find the presence of a high-energy MeV tail beyond a thermal-Comptonization spectrum; however, the tail is much softer and weak…

2012 Monthly Notices of the Royal Astronomical Society
INTEGRAL 68
Evolution of dust in the Orion Bar with Herschel. I. Radiative transfer modelling
DOI: 10.1051/0004-6361/201118537 Bibcode: 2012A&A...541A..19A

Abergel, A.; Martin, P. G.; White, G. J. +5 more

Context. Interstellar dust is a key element in our understanding of the interstellar medium and star formation. The manner in which dust populations evolve with the excitation and the physical conditions is a first step in comprehending the evolution of interstellar dust.
Aims: Within the framework of the Evolution of interstellar dust Hersch…

2012 Astronomy and Astrophysics
Herschel 68