# Talent

### Site Tools

culinary_services

# Differences

This shows you the differences between two versions of the page.

 culinary_services [2014/06/05 15:20]warren culinary_services [2014/06/06 15:52] (current)long Both sides previous revision Previous revision 2014/06/06 15:52 long 2014/06/06 15:52 long 2014/06/06 15:52 long 2014/06/06 15:52 long 2014/06/06 15:51 long 2014/06/06 15:50 long 2014/06/06 15:22 long 2014/06/06 14:35 long 2014/06/06 14:23 long 2014/06/06 14:06 long 2014/06/06 13:31 long 2014/06/05 15:20 warren 2014/06/05 15:20 warren 2014/06/05 15:18 warren 2014/06/05 15:18 warren 2014/06/05 15:16 warren 2014/06/05 15:15 warren 2014/06/05 15:14 warren 2014/06/05 15:14 warren 2014/06/05 15:07 warren 2014/06/05 15:05 warren 2014/06/05 15:04 warren 2014/06/05 14:59 warren 2014/06/05 14:59 warren 2014/06/05 14:58 warren 2014/06/05 14:57 warren 2014/06/05 14:57 warren 2014/06/05 14:55 warren 2014/06/04 15:11 long 2014/06/03 18:47 long 2014/06/03 18:43 long 2014/06/03 17:10 parzuchowski 2014/06/03 17:06 parzuchowski 2014/06/03 17:05 parzuchowski 2014/06/03 17:04 parzuchowski 2014/06/03 16:14 parzuchowski 2014/06/03 08:32 long 2014/06/02 17:58 long Next revision Previous revision 2014/06/06 15:52 long 2014/06/06 15:52 long 2014/06/06 15:52 long 2014/06/06 15:52 long 2014/06/06 15:51 long 2014/06/06 15:50 long 2014/06/06 15:22 long 2014/06/06 14:35 long 2014/06/06 14:23 long 2014/06/06 14:06 long 2014/06/06 13:31 long 2014/06/05 15:20 warren 2014/06/05 15:20 warren 2014/06/05 15:18 warren 2014/06/05 15:18 warren 2014/06/05 15:16 warren 2014/06/05 15:15 warren 2014/06/05 15:14 warren 2014/06/05 15:14 warren 2014/06/05 15:07 warren 2014/06/05 15:05 warren 2014/06/05 15:04 warren 2014/06/05 14:59 warren 2014/06/05 14:59 warren 2014/06/05 14:58 warren 2014/06/05 14:57 warren 2014/06/05 14:57 warren 2014/06/05 14:55 warren 2014/06/04 15:11 long 2014/06/03 18:47 long 2014/06/03 18:43 long 2014/06/03 17:10 parzuchowski 2014/06/03 17:06 parzuchowski 2014/06/03 17:05 parzuchowski 2014/06/03 17:04 parzuchowski 2014/06/03 16:14 parzuchowski 2014/06/03 08:32 long 2014/06/02 17:58 long 2014/06/02 17:57 long 2014/06/02 17:56 long 2014/06/02 17:54 long 2014/06/02 17:52 long 2014/06/02 17:50 long 2014/06/02 17:40 long 2014/06/02 16:45 long 2014/06/02 16:45 long 2014/06/01 22:20 long 2014/06/01 20:48 long 2014/06/01 20:46 long 2014/06/01 20:46 long 2014/05/30 17:35 parzuchowski Line 1: Line 1: + ==========Culinary Services========== + We are Culinary Services. \\ We are Culinary Services. \\ - \\ - Who ordered the extra side of <​sup>​44​Ti?​ - **GROUP MEMBERS**\\ **GROUP MEMBERS**\\ Line 10: Line 9: ==== TOPIC ==== ==== TOPIC ==== - Sensitivity ​studied ​of <​sup>​44​Ti production in in core-collapse supernova environments. + Sensitivity ​studiy ​of <​sup>​44​Ti ​and <​sup>​56​Ni ​production in in core-collapse supernova environments. ===Scientific Background=== ===Scientific Background=== Line 16: Line 15: There are many uncertainties in our understanding of core-collapse supernovae, including the explosion mechanism and nucleosynthesis. ​ One way to gain insight into these phenomena is to study the nucleosynthesis of radioactive isotopes in the shock-heated material. ​ These isotopes, such as <​sup>​44​Ti and <​sup>​56​Ni,​ determine the features of the supernova light curve. ​ Observations of supernova remnants can be used to put bounds on the production of these isotopes. There are many uncertainties in our understanding of core-collapse supernovae, including the explosion mechanism and nucleosynthesis. ​ One way to gain insight into these phenomena is to study the nucleosynthesis of radioactive isotopes in the shock-heated material. ​ These isotopes, such as <​sup>​44​Ti and <​sup>​56​Ni,​ determine the features of the supernova light curve. ​ Observations of supernova remnants can be used to put bounds on the production of these isotopes. - {{ ::​cassa.png?​nolink&​200 |Observation of Cassiopeia A.  Green shows 44Ti distribution,​ blue is 28Si, and the red shows the Fe distribution. ​ (From Grefenstette et al 2014)}} + {{ ::​cassa.png?​nolink&​600 |Observation of Cassiopeia A.  Green shows 44Ti distribution,​ blue is 28Si, and the red shows the Fe distribution. ​ (From Grefenstette et al 2014)}} - Observation of Cassiopeia A.  Green shows <​sup>​44​Ti distribution,​ blue is <​sup>​28​Si,​ and the red shows the Fe distribution. ​ (From Grefenstette et al 2014) + Figure: ​Observation of Cassiopeia A.  Green shows <​sup>​44​Ti distribution,​ blue is <​sup>​28​Si,​ and the red shows the Fe distribution. ​ (From Grefenstette et al 2014) Using simulations,​ we can use these observations to gain insight into the supernova environment. ​ By matching observed abundances, we can gain insight into the environment in which this nucleosynthesis must have taken place and in turn, the details of the explosion mechanism. ​ However, most core-collapse supernova simulations do not include sufficiently large reaction networks to simulate this nucleosynthesis. Using simulations,​ we can use these observations to gain insight into the supernova environment. ​ By matching observed abundances, we can gain insight into the environment in which this nucleosynthesis must have taken place and in turn, the details of the explosion mechanism. ​ However, most core-collapse supernova simulations do not include sufficiently large reaction networks to simulate this nucleosynthesis. Line 25: Line 24: ===Simulations=== ===Simulations=== + ==Parameter Space== We have chosen to do a parameter space study in peak temperature,​ density, and electron fraction, tarting with a set parameter space of peak temperatures [T<​sub>​9​ = 4 - 7] and densities [$\rho$ = 10<​sup>​5​ - 10<​sup>​7​ g/​cm<​sup>​3​] for three values of the electron fraction [Y<​sub>​e​ = 0.45, 0.50, 0.55]. ​ This parameter space roughly corresponds with the shock heated region in simulations of Cassiopeia A-like supernovae (Young & Fryer 2007). We have chosen to do a parameter space study in peak temperature,​ density, and electron fraction, tarting with a set parameter space of peak temperatures [T<​sub>​9​ = 4 - 7] and densities [$\rho$ = 10<​sup>​5​ - 10<​sup>​7​ g/​cm<​sup>​3​] for three values of the electron fraction [Y<​sub>​e​ = 0.45, 0.50, 0.55]. ​ This parameter space roughly corresponds with the shock heated region in simulations of Cassiopeia A-like supernovae (Young & Fryer 2007). + ==Thermodynamic Trajectories== We use analytic adiabatic freeze-out trajectories (Hoyle et al. 1964; Fowler & Hoyle 1964) which satisfy the differential equations: We use analytic adiabatic freeze-out trajectories (Hoyle et al. 1964; Fowler & Hoyle 1964) which satisfy the differential equations: Line 41: Line 42: where $T_0$ and $\rho_0$ are the peak temperature and density in the supernova. ​ where $T_0$ and $\rho_0$ are the peak temperature and density in the supernova. ​ + ==Reaction Network == We used the [[https://​wikihost.nscl.msu.edu/​talent/​lib/​exe/​fetch.php?​media=xnet_public.zip|XNet]] reaction network code.  Our code included 447 isotopes ranging from hydrogen through germanium. ​ We took the reaction rates from the [[https://​groups.nscl.msu.edu/​jina/​reaclib/​db/​library.php?​action=viewsnapshots|JINA Reaclib database]]. ​ We set the threshold temperature for NSE to be 5 GK. We used the [[https://​wikihost.nscl.msu.edu/​talent/​lib/​exe/​fetch.php?​media=xnet_public.zip|XNet]] reaction network code.  Our code included 447 isotopes ranging from hydrogen through germanium. ​ We took the reaction rates from the [[https://​groups.nscl.msu.edu/​jina/​reaclib/​db/​library.php?​action=viewsnapshots|JINA Reaclib database]]. ​ We set the threshold temperature for NSE to be 5 GK. + + ==Initial Abundances and Y$_{e}$== + For any given peak temperature and density, our initial composition was pure $^{28}$Si (therefore Y$_{e}$ = .5) In order to change the initial Y$_{e}$, we just added protons or neutrons to the initial composition according to the following equations: ​ + + + X(^{28}Si) = 1 - \left | 2Y_{e} - 1 \right | \\ + X(p) = \left | 2Y_{e} - 1 \right |  \hspace{1cm} ​ X(n) = \left | 2Y_{e} - 1 \right | \\ + proton-rich \hspace{1cm} neutron-rich + + + Finally we looked at the mass fraction of several isotopes. In particular, $^{4}$He, $^{28}$Si, $^{44}$Ti, and $^{56}$Ni. We then compare our results to that of Magkotsios //et al// with in our parameter space. ​ ===Results=== ===Results=== + + ==$^{44}$Ti Production== + {{ :​44ti.png?​nolink&​900| 44Ti production for a given peak temperature and peak density.}} + $\hspace{2cm}$ $^{44}$Ti production for a given peak temperature and peak density for three different Y$_{e}$'​s + + ==$^{56}$Ni Production== + {{:​56ni.png?​nolink&​900| 56Ni production for a given peak temperature and peak density}} + $\hspace{2cm}$ $^{56}$Ni production for a given peak temperature and peak density for three different Y$_{e}$'​s **REFERENCES** \\ **REFERENCES** \\