Browsing by Title
Now showing items 20470-20489 of 23978
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Spectropolarimetry of the molecular-hydrogen line emission from OMC-1
(1988)Observations of the H2 v = 1-0 S(1) line at 35 km/s velocity resolution were obtained at several locations within OMC-1, including the molecular hydrogen reflection nebula. All line profiles are smooth and show no evidence ... -
Spectropolarimetry of the ultraluminous infrared galaxy IRAS 110548-1131
(1993)From spectropolarimetric observations of the galaxy IRAS 110548-1131 we report very strong, broad H-alpha emission (FWHM 7600 km/s) in the polarized flux spectrum. This suggests that IRAS 110548-1131 has an obscured ... -
Spectropolarimetry of Young and Evolved Stars
(Astronomical Society of the Pacific, 2005)Circumstellar disks play an important role in many stages of the evolution of stars. However, it is only possible to directly image circumstellar disks for a few of the nearest stars. For massive stars, the situation is ... -
Spectroscopic Analysis of Subluminous B Stars in Binaries with Compact Companions
(Astronomical Society of the Pacific, 2007)The masses of compact objects like white dwarfs, neutron stars and black holes are fundamental to astrophysics, but very difficult to measure. We present the results of an analysis of subluminous B (sdB) stars in close ... -
A spectroscopic and proper motion search of Sloan Digital Sky Survey : red subdwarfs in binary systems
(2013-09)Red subdwarfs in binary systems are crucial for both model calibration and spectral classification. We search for red subdwarfs in binary systems from a sample of high proper motion objects with Sloan Digital Sky Survey ... -
Spectroscopic characterisation of close orbiting extrasolar giant planets
(American Institute of Physics (AIP), 2009)A number of successful mid-infrared detections and studies of close orbiting extrasolar giant planetary atmospheres have been responsible for both driving and informing modelling efforts. Recent models have indicated that ... -
Spectroscopic Confirmation of a Population of Isolated, Intermediate-mass Young Stellar Objects
(2023-01-31)Wide-field searches for young stellar objects (YSOs) can place useful constraints on the prevalence of clustered versus distributed star formation. The Spitzer/IRAC Candidate YSO (SPICY) catalog is one of the largest ... -
Spectroscopic confirmation of four metal-poor galaxies at z=10.3-13.2
(2023-05)Finding and characterizing the first galaxies that illuminated the early universe at cosmic dawn is pivotal to understand the physical conditions and the processes that led to the formation of the first stars. In the first ... -
Spectroscopic confirmation of high-amplitude eruptive YSOs and dipping giants from the VVV survey
(2024-02-01)During the pre-main-sequence (pre-MS) evolution stage of a star, significant amounts of stellar mass are accreted during episodic accretion events, such as multidecade FUor-type outbursts. Here, we present a near-infrared ... -
Spectroscopic follow-up of ultraviolet-excess objects selected from the UVEX survey
(2012-10-21)We present the results of the first spectroscopic follow-up of 132 optically blue ultraviolet (UV)-excess sources selected from the UV-Excess Survey of the Northern Galactic Plane (UVEX). The UV-excess spectra are classified ... -
Spectroscopic signatures of youth in low-mass kinematic candidates of young moving groups
(2014-04-21)We present a study of age-related spectral signatures observed in 25 young low-mass objects that we have previously determined as possible kinematic members of five young moving groups: the Local Association (Pleiades ... -
A spectroscopic study of a large sample of L/T transition brown dwarfs
(University of Hertfordshire, 2014-09-25)In this thesis I present the spectroscopic analysis of a large sample of L and T dwarfs, in order to constrain the sub-stellar initial mass function and formation history. The main points I tried to address are the ...