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Related papers: The sigma Orionis substellar population

200 papers

We present the results of a 0.5-0.9" FWHM imaging survey at K (2.2 micron) and H (1.6 micron) covering 5.1' x 5.1' centered on Theta 1C Ori, the most massive star in the Orion Nebula Cluster (ONC). At the age and distance of this cluster,…

Astrophysics · Physics 2009-10-05 Lynne A. Hillenbrand , John M. Carpenter

We present precise constraints on the normalization of the power spectrum of mass fluctuations in the nearby universe, sigma_8, as a function of the mean local matter density, Omega_m. Using the observed local X-ray luminosity function of…

Astrophysics · Physics 2008-11-26 S. W. Allen , R. W. Schmidt , A. C. Fabian , H. Ebeling

'Isolated planetary mass objects' (IPMOs) have masses close to or below the Deuterium-burning mass limit (~15 Jupiter masses) -- at the bottom of the stellar initial mass function. We present an exploratory survey for disks in this mass…

Astrophysics · Physics 2015-05-13 Aleks Scholz , Ray Jayawardhana

ALMA has detected substructures in numerous protoplanetary disks at radii from a few to over a hundred au. These substructures are commonly thought to be associated with planet formation, either by serving as sites fostering planetesimal…

Earth and Planetary Astrophysics · Physics 2024-11-05 Jane Huang , Megan Ansdell , Tilman Birnstiel , Ian Czekala , Feng Long , Jonathan Williams , Shangjia Zhang , Zhaohuan Zhu

Here we present the Spitzer IRS spectrum of CVSO 224, the sole transitional disk located within the ~10 Myr old 25 Orionis group in Orion OB1a. A model fit to the spectral energy distribution of this object indicates a ~7 AU inner disk hole…

We explore the near-infrared properties of galaxies within 27 galaxy clusters using data from the Two Micron All Sky Survey (2MASS). For a subsample of 13 clusters with available X-ray imaging data, we examine both the properties of the…

Astrophysics · Physics 2009-11-07 Yen-Ting Lin , Joseph J. Mohr , S. A. Stanford

We present results of a 90 ksec Chandra X-ray observation of the young sigma Orionis cluster (age ~3 Myr) obtained with the High Energy Transmission Grating Spectrometer. We use the high resolution grating spectrum and moderate resolution…

Astrophysics · Physics 2009-11-13 S. L. Skinner , K. R. Sokal , D. H. Cohen , M. Gagne , S. P. Owocki , R. D. Townsend

We present the first scientific images obtained with a deformable secondary mirror adaptive optics system. We utilized the 6.5m MMT AO system to produce high-resolution (FWHM=0.07'') near infrared (1.6 um) images of the young (~1 Myr) Orion…

We present deep 1.8 cm (16 GHz) radio continuum imaging of seven young stellar objects in the Taurus molecular cloud. These objects have previously been extensively studied in the sub-mm to NIR range and their SEDs modelled to provide…

We explore the near-infrared (NIR) $K$-band properties of galaxies within 93 galaxy clusters and groups using data from the 2MASS. We use X-ray properties of these clusters to pinpoint cluster centers and estimate cluster masses. By…

Astrophysics · Physics 2008-11-26 Yen-Ting Lin , Joseph J. Mohr , S. Adam Stanford

We present 8--13 micron low resolution spectra (R~100) of 8 low-mass protostellar objects ("proplyds") in the Orion Nebula using the Long Wavelength Spectrometer (LWS) at the W. M. Keck Observatory. All but one of the sources in our sample…

Astrophysics · Physics 2009-11-11 R. Y. Shuping , Marc Kassis , Mark Morris , Nathan Smith , John Bally

We have carried out a high spectral resolution line survey towards the Orion Kleinmann-Low (KL) cluster from 44-188 um. The observations were taken with the Long Wavelength Spectrometer (LWS) in Fabry-Perot mode, on board the Infrared Space…

BIMA observations of the Orion nebula discovered a giant flare from a young star previously undetected at millimeter wavelengths. The star briefly became the brightest compact object in the nebula at 86 GHz. Its flux density increased by…

We present near-infrared integral-field spectroscopic observations targeting H$\alpha$ in eight sub-millimeter galaxies (SMGs) at $z$=1.3-2.5 using VLT/SINFONI, obtaining significant detections for six of them. The star formation rates…

We have identified three faint new members of the eta Chamaeleontis cluster. Spectral types of the new members are estimated to be ~M5 based on their TiO band strengths and broadband colors. With an age of 5-8 Myr for the cluster, masses of…

Astrophysics · Physics 2009-11-10 Inseok Song , B. Zuckerman , M. S. Bessell

We present new KPNO 0.9-m optical and VLA HI spectral line observations of the Orion dwarf galaxy. This nearby (D ~ 5.4 Mpc), intermediate-mass (M_dyn = 1.1x10^10 Solar masses) dwarf displays a wealth of structure in its neutral ISM,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 John M. Cannon , Korey Haynes , Hans Most , John J. Salzer , Kaitlin Haugland , Jillian Scudder , Arthur Sugden , Jacob Weindling

We report on the detection of a population of weak metal-line absorbers in the halo or nearby intergalactic environment of the Milky Way. Using high-resolution ultraviolet absorption-line spectra of bright QSOs obtained with the Space…

Astrophysics of Galaxies · Physics 2014-11-18 Philipp Richter , Jane C. Charlton , Alessio P. M. Fangano , Nadya Ben Bekhti , Joseph R. Masiero

We have imaged the enigmatic radio source-I (Orion-I) in the Orion-KL nebula with the VLA at 43 GHz with 34 mas angular resolution. The continuum emission is highly elongated and is consistent with that expected from a nearly edge-on disk.…

Astrophysics · Physics 2009-06-23 M. J. Reid , K. M. Menten , L. J. Greenhill , C. J. Chandler

The nearby high-mass star binary system Theta 1 Orionis C is the brightest and most massive of the Trapezium OB stars at the core of the Orion Nebula Cluster, and it represents a perfect laboratory to determine the fundamental parameters of…

We present high resolution optical spectra obtained with the HIRES spectrograph on the Keck I telescope of low mass T Tauri stars and brown dwarfs (LMTTs) in Taurus-Auriga. Of particular interest is the previously classified "continuum T…

Astrophysics · Physics 2009-11-07 Russel White , Gibor Basri