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Nuclear Reaction Network Calculations: The Next Generation. Brad Meyer Clemson University. John C. Calhoun. Fort Hill. Anna Maria Calhoun. Thomas Clemson. Farmer’s Hall. Tillman Hall. Outline. Brief introduction to reaction networks and nuclear data needs
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Nuclear Reaction Network Calculations: The Next Generation Brad Meyer Clemson University
Outline • Brief introduction to reaction networks and nuclear data needs • libnucnet as an example of a next generation nuclear network • Concern: nuclear database • Proposal: nuclear theory HUB
www.webnucleo.org/home/movies/alpha_rich/mpg/abundance_histogram.mpgwww.webnucleo.org/home/movies/alpha_rich/mpg/abundance_histogram.mpg
The full network • >4000 nuclear species • 73364 in the current JINA reaclib database (excluding any other special reactions)
www.webnucleo.org/home/movies/r_process/mpg/abund_rprocess.mpgwww.webnucleo.org/home/movies/r_process/mpg/abund_rprocess.mpg
www.webnucleo.org/home/movies/r_process/mpg/qse_rprocess.mpg
libnucnet as an example of the next generation of reaction networks
What is libnucnet? • A C toolkit for storing and managing nuclear reaction network. • Built on top of libxml (the gnome XML parser and toolkit) and gsl (the GNU scientific library). • Released under the GNU General Public License. • Available at http://www.webnucleo.org
History of libnucnet • Original goal—online nucleosynthesis tool • Problem—input over the web • Solution—XML (eXtensible Markup Language) • Libxml as input and output • Libxml has powerful built-in data structures (lists, hashes, trees, etc.)—build new nucleosynthesis code on top of libxml • Hashes provide easy access to data—particularly useful for experimentalists
Features of libnucnet • Intrinsically 3-d • Easily handles an arbitrary nuclear network (bbn to r-process), including (any number of) isomeric states • Reactions are handled the way humans think about them: “c12 + he4 o16 + gamma” or “o15 n15 + positron + neutrino_e” • Hierarchically structured • Naturally uses xml as input (allows for schemas, stylesheets, xpath selection, etc.) • Read and validate data across the web • Allows for user-supplied screening, NSE correction factor functions, and rate fit functions.
Structure of libnucnet • Libnucnet__Nuc.c/h: a collection of nuclei • Libnucnet__Species: a species • Libnucnet__Nuc: a collection of species • Libnucnet__Reac.c/h: a collection of nuclear reactions • Libnucnet__Reaction: a reaction • Libnucnet__Reac: a collection of reactions • Libnucnet.c/h: a network and a collection of zones • Libnucnet__Net: a Libnucnet__Nuc + Libnucnet__Reac • Libnucnet__Zone: a physical zone • Libnucnet: a network plus a collection of zones
XML Data for the nuclear collection <nuclear_data> <!--n--> <nuclide> <z>0</z> <a>1</a> <source>Tuli (2000)</source> <mass_excess>8.071</mass_excess> <spin>0.5</spin> <partf_table> <point> <t9>0.01</t9> <log10_partf>0</log10_partf> </point> <point> <t9>0.15</t9> <log10_partf>0</log10_partf> </point> </partf_table> </nuclide> … </nuclear_data>
XML Data for the nuclear collection (with states) <!--al26--> <nuclide> <z>13</z> <a>26</a> <states> <state id="g"> <source>Tuli (2000) + Gupta and Meyer (2001)</source> <mass>-12.21</mass> <spin>5</spin> <partf_table> ... </partf_table> </state> <state id="m"> <source>Tuli (2000) + Gupta and Meyer (2001)</source> <mass>-11.982</mass> <spin>0</spin> <partf_table> ,,, </partf_table> </state> </states> </nuclide>
XML Data for Reactions—a rate table <reaction_data> <!-- h1 + n -> h2 + gamma --> <reaction> <source>Smith et al. (1993)</source> <reactant>h1</reactant><reactant>n</reactant> <product>h2</product><product>gamma</product> <rate_table> <point> <t9>0.001</t9> <rate>4.6168E+04</rate> <sef>1.000</sef> </point> … </rate_table> </reaction> …. </reaction_data>
XML Data for Reactions—a single rate <!-- o19 -> f19 + electron + anti-neutrino_e --> <reaction> <source>Nuclear Data tables</source> <reactant>o19</reactant> <product>f19</product> <product>electron</product> <product>anti-neutrino_e</product> <single_rate>1.6251e-01</single_rate> </reaction>
XML Data for Reactions—a non-smoker fit • <!– ne15 + n -> ne16 + gamma -> • <reaction> • <source>ADNDT (2001) 75, 1 (non-smoker)</source> • <reactant>ne15</reactant> <reactant>n</reactant> • <product>ne16</product> <product>gamma</product> • <non_smoker_fit> • <Zt> 10</Zt> • <At> 15</At> • <Zf> 10</Zf> • <Af> 16</Af> • <Q> 8.071000</Q> • <spint> 0.0000</spint> • <spinf> 0.0000</spinf> • <TlowHf>-1.0000</TlowHf> • <Tlowfit> 0.0100</Tlowfit> • <acc> 1.900000e-06</acc> • <a1> 6.225343e+00</a1> • <a2> 1.023384e-02</a2> • <a3>-1.272184e+00</a3> • <a4> 3.920127e+00</a4> • <a5>-1.966720e-01</a5> • <a6> 1.394263e-02</a6> • <a7>-1.389816e+00</a7> • <a8> 2.983430e+01</a8> • </non_smoker_fit> • </reaction>
Zone data <zone_data> <zone label1="x1" label2="y1" label3="z1"> <nuclide> <z>0</z> <a>1</a> <x>0.5</x> </nuclide> <nuclide name=“h1”> <x>0.5</x> </nuclide> </zone> … </zone_data>
26Mg(alpha,n)29Si rate x 3 Hoppe, BSM, et al. (2009)
Future of nuclear data for reaction network calculations • Reaction data—JINA reaclib database in libnucnet xml format • Nuclear data????
Where I’m headed • Study nuclear network equilibria (NSE, QSE, etc.)libnuceq • Build a multi-zone Galactic chemical evolution network on top of libnucnet.
HUBzero http://hubzero.org/tour
Deploying a Tool http://nanohub.org/resources/3863
Outline • Brief introduction to reaction networks and nuclear data needs • libnucnet as an example of a next generation nuclear network • Concern: nuclear database • Proposal: nuclear theory HUB