The Starburst Imf – an Impossible Measurement?
نویسندگان
چکیده
The starburst IMF is probably as much of theoretical interest and practical relevance as it is a subject of observational controversy. In this conference paper we review the most common methods (star counts, dynamical masses, and line ratios) to derive or constrain the IMF, and discuss potential problems and shortcomings that often lead to claims of anomalous IMF slopes and mass cut-offs.
منابع مشابه
The Imf in Starbursts
The history of the IMF in starburst regions is reviewed. The IMFs are no longer believed to be top-heavy, although some superstar clusters, whether in starburst regions or not, could be. General observations of the IMF are discussed to put the starburst results in perspective. Observed IMF variations seem to suggest that the IMF varies a little with environment in the sense that denser and more...
متن کاملPresent-day scaling relations of submm galaxies: origin of spheroidal sytems
We analyse the spectral energy distributions (SEDs) of 23 submm galaxies and 3 ISOdetected EROs, all of which have the spectroscopic redshifts, by using an evolutionary SED model of starbursts. This SED model allows us to investigate intrinsic properties of starbursts, such as the starburst age and the mean stellar metallicity, as it takes into account the chemical evolution. Also, the intrinsi...
متن کاملThe Imf of the Massive Star-forming Region Ngc 3603 from Nir Ao Observations
We study the initial mass function (IMF) of one of the most massive galactic star-forming regions NGC 3603 to answer a fundamental question in current astrophysics: is the IMF universal, or does it vary? Using our very deep high angular resolution JHKSL ′ images obtained with the AO-assisted NAOS-CONICA instrument at the VLT/ESO, we have successfully revealed the low-mass stellar population dow...
متن کاملThe Nuclear Starburst in Ngc 253
We have obtained long-slit spectra of NGC 253 in the J, H, K, and N bands, broadband images in the J, H, and K s bands, narrowband images centered at the wavelengths of Brγ and H 2 (1,0)S(1), and imaging spectroscopy centered on [Ne II](12.8µm). We have subtracted a composite stellar spectrum from the galaxy spectrum to measure faint emission lines which otherwise would be buried in the complic...
متن کاملModeling a high mass turn down in the stellar initial mass function
Statistical sampling from the stellar initial mass function (IMF) for all star-forming regions in the Galaxy would lead to the prediction of ∼ 1000 M⊙ stars unless there is a rapid turn-down in the IMF beyond several hundred solar masses. Such a turndown is not necessary for dense clusters because the number of stars sampled is always too small. Although no upper mass limits to star formation h...
متن کامل