8 research outputs found
The rates of Type Ia Supernovae. II. Diversity of events at low and high redshift
This paper investigates on the possible systematic difference of Supernovae
Ia (SN Ia) properties related to the age and masses of the progenitors that
could introduce a systematic bias between low and high redshift SN Ia's. The
relation between the main features of the distribution of the delay times (DTD)
and the masses of the progenitors is illustrated for the single (SD) and double
degenerate (DD) models. Mixed models, which assume contributions from both the
SD and DD channels, are also presented and tested versus the observed
correlations between the SN Ia rates and the parent galaxy properties. It is
shown that these correlations can be accounted for with both single channel and
mixed models, and that the rate in S0 and E galaxies may effectively provide
clues on the contribution of SD progenitors to late epoch explosions. A wide
range of masses for the CO WD at the start of accretion is expected in almost
all galaxy types; only in galaxies of the earliest types the properties of the
progenitors are expected to be more uniform. For mixed models, late type
galaxies should host SD and DD explosions in comparable fractions, while in
early type galaxies DD explosions should largely prevail. Events hosted by star
forming galaxies span a wide range of delay times; \textit{prompt} events could
dominate only in the presence of a strong star-burst. It is concluded that
nearby SN Ia samples should well include the young, massive and hot progenitors
that necessarily dominate at high redshift.Comment: 22 pages, 15 figures, MNRAS accepte
Virtualization and grid utilization within the CANFAR project
The Canadian Advanced Network For Astronomical Research (CANFAR) is an operational system for the delivery, processing, storage, analysis, and distribution of very large astronomical datasets. CANFAR combines the Canadian national research network (CANARIE), grid processing and storage resources (Compute Canada) and a data center (CADC) into a unified Platform-as-a-service (PaaS) cyberinfrastructure supporting Canadian astronomy projects. The CANFAR processing service is based on virtualization and combines features of the grid and cloud processing models to provide a self-configuring virtual cluster deployed on multiple cloud clusters. The service makes use of many technologies from the grid, cloud and Virtual Observatory communities.Peer reviewed: YesNRC publication: Ye