Guided Tour - Part 1
This is the guided tour to setting the nuclear-reaction network and the parameters for your online nucleosynthesis calculation. As you gain familiarity with the web site, you will be able to use the All-in-One tool to set up your calculation more quickly.
Your first task is to set up the nuclear-reaction network, that is, the set of nuclei you wish to include in the calculation. For each element (denoted by its charge number Z), choose a beginning neutron number N1 and an ending neutron number N2. All isotopes within the mass range A1=Z+N1 to A2=Z+N2 will be included in the network. For example, for oxygen (Z=8), if you chose N1=7 and N2=10, your network will include 15O, 16O, 17O, and 18O. Certain isotopes unstable to electro-magnetic or strong interaction decays are never included (namely, 5He, ... Brad). Neutron, protons, and alpha particles (4He) are always included.
Enter your network in the top window. Please use XML format (see Help side bar). You may paste your own network into the window. Alternatively, you may choose one of the five preset networks from the pull-down menu. These five networks range in size from A, the smallest (and fastest to run) to E, the largest (and slowest to run). Brad will provide these.
XML, eXtensible Markup Language, is used on this website in order to enter tables of data. You will need to make your data into an XML format in order for it to be readable by these applets.
Why XML: Different internet browsers, computer operating systems, and even program applications, have different versions of what a space or end-of-line character is. Because many internet applications, including Java, are very sensitive to these differences, a way around it is to format data so that only that which are set inside special tags is read.
This is the format that is fast-becoming a standard, for it is easy to use, write parsers for, and get past these special character problems.
Network XML Tags: This applet uses the tags <z>, <n1>, and <n2> for the various parameters. For example, if you wish to enter oxygen as part of your network, and you want it to run from 15O through18O, then the correct XML would be:
<z>8</z><n1>15</n1><n2>18</n2>
What goes between the tags does not matter -- only what is inside is read by the parser.