Time-dependent stellar models.

Relativistic Stellar Models with Quadratic Equation of State

In this paper, we have obtained and presented new relativistic stellar configurations considering an anisotropic fluid distribution with a charge distribution and a gravitational potential Z(x) that depends on an adjustable parameter. The quadratic equation of state based on Feroze and Siddiqui viewpoint is used for the matter distribution. The new solutions can be written in terms of elementar...

Space-time models with time-dependent covariates

Stellar Mass Dependent Disk Dispersal

We use published optical spectral and IR excess data from nine young clusters and associations to study the stellar mass dependent dispersal of circumstellar disks. All clusters older than ∼3Myr show a decrease in disk fraction with increasing stellar mass for Solar to higher mass stars. This result is significant at about the 1σ level in each cluster. For the complete set of clusters we reject...

Competing risks models and time-dependent covariates

New statistical models for analysing survival data in an intensive care unit context have recently been developed. Two models that offer significant advantages over standard survival analyses are competing risks models and multistate models. Wolkewitz and colleagues used a competing risks model to examine survival times for nosocomial pneumonia and mortality. Their model was able to incorporate...

Stellar yields in CNO from rotating stellar models

For 12 C and 16 O, rotating models predict in general enhanced yields. At high metallicity, the carbon and oxygen yields from the very high mass stars, which go through a WR phase, are little affected by rotation. For 14 N, rotation allows the production of important amounts of primary nitrogen in intermediate mass stars at very low metallicity. The process invoked for this production is differ...