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group2 [2014/06/09 16:45]
group2 [2014/06/13 08:49] (current)
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-====== BSM BBN ======+====== ​$^{\rm ​BSM}_{\rm\ \ BBN}$ ======
 ==== Group ==== ==== Group ====
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 ==== Task ==== ==== Task ====
 We will explore the impact of non-standard model physics on BBN: We will explore the impact of non-standard model physics on BBN:
-  * Varying ​Λ<​sub> ​QCD</​sub>​+  * Varying ​$\Lambda_{QCD}$
   * Neutron magnetic moment   * Neutron magnetic moment
-  * ...+  * Variations in gravitational constant 
 +==== Results ==== 
 +For our results, please refer to our {{::​bsmbbn-presentation.pdf|final presentation}}
 ==== Logbook ==== ==== Logbook ====
 === Monday, June 9 === === Monday, June 9 ===
 +  * decided on project topic
 +  * started familiarizing with BBN code and researching required inputs
 +=== Tuesday, June 10 ===
 +  * wrote wrapper script enabling us to vary some of the constants like neutron and proton mass, gravitational constant, Hubble parameter etc.
 +  * ran calculations of BBN dependence on grav. constant; H0 seems to be unused by the code, so varying it does not lead anywhere.
 +  * varying $\Lambda_{QCD}$ and the neutron magnetic moment both incluence the deuteron formation rate $p(n,​\gamma)d$. Hence we rewrote this rate with parameters in the ''​bigbang.f90''​ code and [[group2_code|wrote a wrapper script]] which reads in a table with sets of parameters and calculates the BBN composition
 +  * started figuring out how the proton-neutron mass splitting and the deuteron properties depend on our input parameters
 +  * fixed several bugs in the code, continued familiarizing ourselves with Fortran and the BBN code
 +=== Wednesday, June 11 ===
 +  * produced plots of BBN abundance as function of grav. constant
 +  * tried to calculate and fit the $p(n,​\gamma)d$ rate to use as input; partially succeeded
 +=== Thursday, June 12 ===
 +  * produced data and plots for BBN abundance as function of $\Lambda_{QCD}$ and $\mu_n$
 +  * also looked at the individual effects of $\Lambda_{QCD}$ on the actual inputs to the BBN calculation (neutron-proton mass splitting, neutron life time, deuteron energy, $p(n,​\gamma)d$ rate) and identified the life time effect as the main effect driving the change in the <​sup>​4</​sup>​He abundance.
 +  * created {{::​bsmbbn-presentation.pdf|final presentation}}
group2.1402346708.txt.gz · Last modified: 2014/06/09 16:45 by bartl