3
3.0
Jun 30, 2018
06/18
Jun 30, 2018
by
A. Caratti o Garatti; B. Stecklum; R. Garcia Lopez; J. Eislöffel; T. P. Ray; A. Sanna; R. Cesaroni; C. M. Walmsley; R. D. Oudmaijer; W. J. de Wit; L. Moscadelli; J. Greiner; A. Krabbe; C. Fischer; R. Klein; J. M. Ibañez
texts
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Solar-mass stars form via circumstellar disk accretion (disk-mediated accretion). Recent findings indicate that this process is likely episodic in the form of accretion bursts, possibly caused by disk fragmentation. Although it cannot be ruled out that high-mass young stellar objects (HMYSOs; $M>$8 M$_\odot$, $L_{bol}>$5$\times$10$^3$ L$_\odot$) arise from the coalescence of their low-mass brethren, latest results suggest that they more likely form via disks. Accordingly, disk-mediated...
Topics: Astrophysics of Galaxies, Solar and Stellar Astrophysics, Astrophysics
Source: http://arxiv.org/abs/1704.02628
46
46
Sep 22, 2013
09/13
Sep 22, 2013
by
R. Maiolino; A. Comastri; R. Gilli; N. M. Nagar; S. Bianchi; T. Boeker; E. Colbert; A. Krabbe; A. Marconi; G. Matt; M. Salvati
texts
eye 46
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A fraction of active galactic nuclei do not show the classical Seyfert-type signatures in their optical spectra, i.e. they are optically "elusive". X-ray observations are an optimal tool to identify this class of objects. We combine new Chandra observations with archival X-ray data in order to obtain a first estimate of the fraction of elusive AGN in local galaxies and to constrain their nature. Our results suggest that elusive AGN have a local density comparable to or even higher...
Source: http://arxiv.org/abs/astro-ph/0307380v2
33
33
Sep 20, 2013
09/13
Sep 20, 2013
by
S. A. Wright; J. E. Larkin; M. Barczys; D. K. Erb; C. Iserlohe; A. Krabbe; D. R. Law; M. W. McElwain; A. Quirrenbach; C. C. Steidel; J. Weiss
texts
eye 33
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We present 0.1" resolution near-infrared integral field spectroscopy of Halpha in a z=1.4781 star forming galaxy, Q2343-BM133. These observations were obtained with OSIRIS (OH Suppressing Infra-Red Imaging Spectrograph) using the W.M. Keck Observatory Laser Guide Star Adaptive Optics system. Halpha emission is resolved over a 0.8" (6.8 kpc) x 0.5" (4.3 kpc) region with a 0.1" spatial resolution. We find a global flux of 4.2+/-0.6x10^{-16} ergs s^{-1} cm^{-2}, and detect a...
Source: http://arxiv.org/abs/astro-ph/0612199v1
32
32
Sep 20, 2013
09/13
Sep 20, 2013
by
E. T. Young; E. E. Becklin; P. M. Marcum; T. L. Roellig; J. M. De Buizer; T. L. Herter; R. Güsten; E. W. Dunham; P. Temi; B. -G. Andersson; D. Backman; M. Burgdorf; L. J. Caroff; S. C. Casey; J. A. Davidson; E. F. Erickson; R. D. Gehrz; D. A. Harper; P. M. Harvey; L. A. Helton; S. D. Horner; C. D. Howard; R. Klein; A. Krabbe; I. S. McLean; A. W. Meyer; J. W. Miles; M. R. Morris; W. T. Reach; J. Rho; M. J. Richter; H. -P. Roeser; G. Sandell; R. Sankrit; M. L. Savage; E. C. Smith; R. Y. Shuping; W. D. Vacca; J. E. Vaillancourt; J. Wolf; H. Zinnecker
texts
eye 32
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The Stratospheric Observatory for Infrared Astronomy (SOFIA) is an airborne observatory consisting of a specially modified Boeing 747SP with a 2.7-m telescope, flying at altitudes as high as 13.7 km (45,000 ft). Designed to observe at wavelengths from 0.3 micron to 1.6 mm, SOFIA operates above 99.8 % of the water vapor that obscures much of the infrared and submillimeter. SOFIA has seven science instruments under development, including an occultation photometer, near-, mid-, and far-infrared...
Source: http://arxiv.org/abs/1205.0791v1
49
49
Sep 19, 2013
09/13
Sep 19, 2013
by
R. Maiolino; A. Krabbe; N. Thatte; R. Genzel
texts
eye 49
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We present high angular resolution (0".15-0".5) near infrared images and spectroscopy of the Circinus galaxy, the closest Seyfert 2 galaxy known. The data reveal a non-stellar nuclear source at 2.2 microns. The coronal line region and the hot molecular gas emission extend for 20-50 pc in the ionization cone. The data do not show evidence for a point-like concentration of dark mass; we set an upper limit of 4*10^6 Mo to the mass of a putative black hole. We find evidence for a young...
Source: http://arxiv.org/abs/astro-ph/9709091v2
30
30
Sep 19, 2013
09/13
Sep 19, 2013
by
M. Hamidouche; E. Young; P. Marcum; A. Krabbe
texts
eye 30
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We present one of the new generations of observatories, the Stratospheric Observatory For Infrared Astronomy (SOFIA). This is an airborne observatory consisting of a 2.7-m telescope mounted on a modified Boeing B747-SP airplane. Flying at an up to 45,000 ft (14 km) altitude, SOFIA will observe above more than 99 percent of the Earth's atmospheric water vapor allowing observations in the normally obscured far-infrared. We outline the observatory capabilities and goals. The first-generation...
Source: http://arxiv.org/abs/1010.0723v1
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27
Sep 18, 2013
09/13
Sep 18, 2013
by
T. Boeker; A. Krabbe; J. W. V. Storey
texts
eye 27
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We report on mid-infrared (MIR) continuum and line emission mapping of the nucleus of NGC 253. The data, with a resolution of 1\as.4, reveal a double-peaked arc-like [NeII] emission region. Comparison with published data shows that the [NeII] arc is centered on the nucleus of the galaxy. The brightest [NeII] source coincides with the infrared continuum peak. The interpretation of these results is complicated by the edge-on orientation of NGC 253, but a self-consistent explanation is...
Source: http://arxiv.org/abs/astro-ph/9803108v1
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34
Sep 18, 2013
09/13
Sep 18, 2013
by
A. Krabbe; C. Iserlohe; J. E. Larkin; M. Barczys; M. McElwain; J. Weiss; S. A. Wright; A. Quirrenbach
texts
eye 34
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We present diffraction limited spectroscopic observations of an infrared flare associated with the radio source SgrA*. These are the first results obtained with OSIRIS, the new facility infrared imaging spectrograph for the Keck Observatory operated with the laser guide star adaptive optics system. After subtracting the spectrum of precursor emission at the location of Sgr A*, we find the flare has a spectral index of -2.6 +- 0.9. If we do not subtract the precursor light, then our spectral...
Source: http://arxiv.org/abs/astro-ph/0605253v1
64
64
Jul 20, 2013
07/13
Jul 20, 2013
by
W. Brandner; S. Sheppard; H. Zinnecker; L. Close; F. Iwamuro; A. Krabbe; T. Maihara; K. Motohara; D. L. Padgett; A. Tokunaga
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eye 64
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Observations of the rho Ophiuchi star forming region with VLT ANTU and ISAAC under 0.35" seeing conditions reveal two bipolar reflection nebulosities intersected by central dust lanes. The sources (OphE-MM3 and CRBR 2422.8-3423) can be identified as spatially resolved circumstellar disks viewed close to edge-on, similar to edge-on disk sources discovered previously in the Taurus and Orion star forming regions. Millimeter continuum fluxes yield disk masses of the order of 0.01 Mo, i.e....
Source: http://arxiv.org/abs/astro-ph/0009141v1
