Working with GALPROP

NEW MEXICO AMPALLIANCE FOR MINORITY PARTICIPATION

Melinda Guzman and Samantha ChaconElectrical and Computer Engineering

Drs. Steve Stochaj, Heather Pfeiffer, Jeanine CookURA

Working with GALPROP


Outline

Science Background Code Background CPA Background Examples Test, Result and Analysis Pit Falls Challenges Future Work


Science Background

Computational Astrophysics Using a computer to numerically solve research

problems

Computers are being used because the models for describing the astrophysical systems are complex

Understanding Astrophysics The study of stars, planets and asteroids

What is visible in the sky (Universe)

Understand the Universe


Science Background

Understanding the Universe Means having a type of model that will predict

phenomena that has yet to be observed but will be in the near future

Focus on cosmic rays Fast moving charged particles that spread through the

galaxies Important ingredient for the interstellar medium

Interstellar medium is the space between the stars


Interstellar Medium

Interstellar Medium

Courtesy of Dr. Steve Stochaj


Science Background

Galaxies Collection of multiple stars and interstellar matter

Milky Way Galaxy we live in

Milky Way


Dark Matter

We all know what matter is: person, place, or thing When it comes to dark matter we don't know what it is

for sure

Theorized to be matter which is invisible with the direct measurement

Science has proven it exists in our Universe

Many unanswered questions about dark matter


Dark Matter


Dark Matter


Code Background

GALPROP Provided Stanford University

Supported by NASA

Numerical Modeling systems

Perform cosmic-ray propagation calculations The set of model parameters take large amounts of

computer time Complex programs

Test parameters


Challenges of Working with GALPROP

Learn more about Linux In general

Familiarize with the commands Why it needs to be specific in the code

Compiling the program Running the program so we get an output

Pit Falls


CPA Background

Computer Performance Analysis over all goals Improve performance

Mix and match to see which computer architecture will maximize the program's abilities

Compare and match computational requirements with the physical attributes of a computer platform


CPA Review

Computer Performance Analysis Profiling

Determine which portion of the code takes the most computer time

Improve the speed Want the program to run as fast as possible

Perform a trace analysis How the program runs on different architectures


CPA Review

Computer Performance Analysis (continued) Test various computer architectures

Meet the specifications of the code while maintaining the speed


A Sample Function for Analysis

#include <stdio.h>

long fibonacci_i( int k );

int main( void ) {

int n;

printf("Enter a positive integer number -> ");

scanf("%d", &n);

printf("Iterative Fibonacci number = %ld\n",

fibonacci_i(n));

return 0;

}/* main */

long fibonacci_i( int k ) {

long term = 1, prev1 = 1, prev2 = 1;

int n;

if (k > 1)

{

for(n=2; n<=k; n++)

{

term = prev1 + prev2;

prev2 = prev1;

prev1 = term;

}

}

return term;

}/* fibonacci_i */

Sample Function GPROF Results


Test and Results

Write a c-code

Compile the code

Make the necessary changes if needed

Analyze the results

Graph the results to retrieve a better visual understanding of the


Analysis

From the graphs , we can see that GALPROP takes a lot of time with certain functions

From here we can determine which areas to focus on that need the most improvement

The data cannot be compared until we run it on different computer architectures


Pit Falls

The system can be down (Aussie)

Time consuming (running programs)

Varies in complication ( skills we lack)


Future Work

Test GALPROP on the different architectures

Re- Analyze the output

Optimize the code

Enhance the speed performance


References

http://imagine.gsfc.nasa.gov/docs/science/know_l1/dark_matter.html

http://galprop.stanford.edu/web_galprop/galprop_home.html

http://www2.lns.mit.edu/~LQS/Milky_Way_galaxy_sun05.jpg

http://en.wikipedia.org/wiki/Dark_matter











Special Thanks

Special thanks to Dr.Steve Stochaj, Dr. Heather Pfeiffer, and Dr. Jeanine Cook for giving us the opportunity to be a part of this research project.

Jeanne Garland, URA

NSF HRD 083171

Documents

Working with GALPROP