منابع مشابه
Detection of Beat Cepheids in M33 and Their Use as a Probe of the M33 Metallicity Distribution
Our analysis of the Deep CFHT M33 variability survey database has uncovered 5 Beat Cepheids (BCs) that are pulsating in the fundamental and first overtone modes. With only the help of stellar pulsation theory and of mass–luminosity (M -L) relations, derived from evolutionary tracks, we can accurately determine the metallicities Z of these stars. The [O/H] metallicity gradient of −0.16 dex/kpc t...
متن کاملThe M33 Metallicity Project: Resolving the Abundance Gradient Discrepancies in M33
We present a new determination of the metallicity gradient in M33, based on Keck LRIS measurements of oxygen abundances using the temperature-sensitive emission line [O iii] k4363 in 61 H ii regions. These data approximately triple the sample of direct oxygen abundances in M33. We find a central abundance of 12þ log (O/H) 1⁄4 8:36 0:04 and a slope of 0:027 0:012 dex kpc , in agreement with infr...
متن کاملThe clumpiness of LBV winds
We present the first systematic spectro-polarimetric study of Luminous Blue Variables (LBVs), and find that at least half those objects studied display evidence for intrinsic polarization – a signature of significant inhomogeneity at the base of the wind. Furthermore, multi-epoch observations reveal that the polarization is variable in both strength and position angle. This evidence points away...
متن کاملCool gas and dust in M33: Results from the Herschel M33 extended survey (HERM33ES)
We present an analysis of the first space-based far-IR-submm observations of M 33, which measure the emission from the cool dust and resolve the giant molecular cloud complexes. With roughly half-solar abundances, M33 is a first step towards young low-metallicity galaxies where the submm may be able to provide an alternative to CO mapping to measure their H2 content. In this Letter, we measure ...
متن کاملA Search for 6.7 Ghz Methanol Masers in M33
We report the negative results from a search for 6.7 GHz methanol masers in the nearby spiral galaxy M33. We observed 14 GMCs in the central 4 kpc of the Galaxy, and found 3σ upper limits to the flux density of ∼9 mJy in spectral channels having a velocity width of 0.069 kms. By velocity shifting and combining the spectra from the positions observed, we obtain an effective 3σ upper limit on the...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 1995
ISSN: 0074-1809
DOI: 10.1017/s0074180900202258