Search Publications

Reconstruction of total solar irradiance 1974-2009
DOI: 10.1051/0004-6361/201118702 Bibcode: 2012A&A...541A..27B

Jaffe, A. H.; Krivova, N. A.; Solanki, S. +4 more

Context. The study of variations in total solar irradiance (TSI) is important for understanding how the Sun affects the Earth's climate.
Aims: Full-disk continuum images and magnetograms are now available for three full solar cycles. We investigate how modelled TSI compares with direct observations by building a consistent modelled TSI datase…

2012 Astronomy and Astrophysics
SOHO 95
Stellar population models in the UV. I. Characterisation of the New Generation Stellar Library
DOI: 10.1051/0004-6361/201118065 Bibcode: 2012A&A...538A.143K

Koleva, M.; Vazdekis, A.

Context. The spectral predictions of stellar population models are not as accurate in the ultra-violet (UV) as in the optical wavelength domain. One of the reasons is the lack of high-quality stellar libraries. The New Generation Stellar Library (NGSL), recently released, represents a significant step towards the improvement of this situation.

2012 Astronomy and Astrophysics
eHST 95
An active region filament studied simultaneously in the chromosphere and photosphere. I. Magnetic structure
DOI: 10.1051/0004-6361/201117675 Bibcode: 2012A&A...539A.131K

Martínez Pillet, V.; Centeno, R.; Kuckein, C.


Aims: A thorough multiwavelength, multiheight study of the vector magnetic field in a compact active region filament (NOAA 10781) on 2005 July 3 and 5 is presented. We suggest an evolutionary scenario for this filament.
Methods: Two different inversion codes were used to analyze the full Stokes vectors acquired with the Tenerife Infrared…

2012 Astronomy and Astrophysics
SOHO 93
APEX-CHAMP+ high-J CO observations of low-mass young stellar objects. III. NGC 1333 IRAS 4A/4B envelope, outflow, and ultraviolet heating
DOI: 10.1051/0004-6361/201118368 Bibcode: 2012A&A...542A..86Y

van Dishoeck, Ewine F.; Güsten, Rolf; van der Marel, Nienke +5 more

Context. The NGC 1333 IRAS 4A and IRAS 4B sources are among the most well-studied Stage 0 low-mass protostars, which drive prominent bipolar outflows. Spectrally resolved molecular emission lines provide crucial information about the physical and chemical structure of the circumstellar material as well as the …

2012 Astronomy and Astrophysics
Herschel 92
The nature of the interstellar medium of the starburst low-metallicity galaxy Haro 11: a multi-phase model of the infrared emission
DOI: 10.1051/0004-6361/201219818 Bibcode: 2012A&A...548A..20C

Cooray, A.; Lebouteiller, V.; Madden, S. C. +15 more

Context. The low-metallicity interstellar medium (ISM) is profoundly different from that of normal systems, being clumpy with low dust abundance and little CO-traced molecular gas. Yet many dwarf galaxies in the nearby universe are actively forming stars. As the complex ISM phases are spatially mixed with each other, detailed modeling is needed to…

2012 Astronomy and Astrophysics
Herschel eHST 90
Dark gas in the solar neighborhood from extinction data
DOI: 10.1051/0004-6361/201118740 Bibcode: 2012A&A...543A.103P

Bernard, J. -P.; Fukui, Y.; Onishi, T. +4 more

Context. When modeling infrared or γ-ray data as a linear combination of observed gas tracers, excess emission has been detected compared to expectations from known neutral and molecular gas traced by HI and CO measurements, respectively. This excess might correspond to additional gas component. This so-called “dark gas” (DG) has been observed in …

2012 Astronomy and Astrophysics
Planck 89
Water in star-forming regions with Herschel: highly excited molecular emission from the NGC 1333 IRAS 4B outflow
DOI: 10.1051/0004-6361/201117914 Bibcode: 2012A&A...540A..84H

van Dishoeck, E. F.; Pontoppidan, K. M.; Bergin, E. A. +9 more

During the embedded phase of pre-main sequence stellar evolution, a disk forms from the dense envelope while an accretion-driven outflow carves out a cavity within the envelope. Highly excited (E' = 1000 - 3000 K) H2O emission in spatially unresolved Spitzer/IRS spectra of a low-mass Class 0 object, NGC 1333 IRAS 4B, has previously been…

2012 Astronomy and Astrophysics
Herschel 88
"TNOs are Cool": A survey of the trans-Neptunian region. IV. Size/albedo characterization of 15 scattered disk and detached objects observed with Herschel-PACS
DOI: 10.1051/0004-6361/201118541 Bibcode: 2012A&A...541A..92S

Fornasier, S.; Hartogh, P.; Lellouch, E. +20 more

Context. Physical characterization of trans-Neptunian objects, a primitive population of the outer solar system, may provide constraints on their formation and evolution.
Aims: The goal of this work is to characterize a set of 15 scattered disk (SDOs) and detached objects, in terms of their size, albedo, and thermal properties.
Methods: …

2012 Astronomy and Astrophysics
Herschel 87
The enigmatic nature of the circumstellar envelope and bow shock surrounding Betelgeuse as revealed by Herschel. I. Evidence of clumps, multiple arcs, and a linear bar-like structure
DOI: 10.1051/0004-6361/201219792 Bibcode: 2012A&A...548A.113D

Blommaert, J. A. D. L.; Gomez, H. L.; Barlow, M. J. +13 more

Context. The interaction between stellar winds and the interstellar medium (ISM) can create complex bow shocks. The photometers on board the Herschel Space Observatory are ideally suited to studying the morphologies of these bow shocks.
Aims: We aim to study the circumstellar environment and wind-ISM interaction of the nearest red supergiant,…

2012 Astronomy and Astrophysics
Herschel 87
Detailed abundance analysis from integrated high-dispersion spectroscopy: globular clusters in the Fornax dwarf spheroidal
DOI: 10.1051/0004-6361/201219895 Bibcode: 2012A&A...546A..53L

Larsen, S. S.; Strader, J.; Brodie, J. P.


Aims: We describe our newly developed approach to detailed abundance analysis from integrated-light high-dispersion spectra of star clusters. As a pilot project, we measure abundances of several Fe-peak, α- and neutron capture elements from spectra of three globular clusters (GCs) in the Fornax dwarf spheroidal galaxy, obtained with UVES on t…

2012 Astronomy and Astrophysics
eHST 86