Using Xamine

Using Xamine

This section describes how to use Xamine, the NSCL Spectrum Display program. It is beyond the scope of this document to describe all of the features of the Xamine program. A full user manual is available at: [tp://ftp.nscl.msu.edu/pub/daq/doc/xamine_user.ps] [ftp://ftp.nscl.msu.edu/pub/daq/doc/xamine_user.ps] (warning, this manual is about 130 pages long).

In this section you will learn:

• To recognize the segments of the Xamine user interface.
• How to subdivide the display area so that several spectra can be displayed.
• How to display a set of spectra in the display area.
• How to set the display characteristics of a spectrum.
• How to set a summing region and integrate it.
• How to print spectra.
• How to save and restore a setup so that it can be re-used.

The Xamine User Interface

The figure below shows the Xamine user interface. The window can be stretched as desired to provide more spectrum display room.

As you read the text below, note that the numbers refer to the numeric labels on the figure.

1. The menu bar provides access to almost all of Xamine's capabilities.
2. The display area is where spectra will be displayed.
3. The status bar provides several pieces of information. The Spectrum section identifies which spectrum is selected. The X Y areas tell you where in the spectrum the mouse is. The Counts area displays the number of spectrum counts at the mouse's position.
4. This set of shortcut buttons controls what will be displayed in the display area. The buttons in this box provide shortcuts to some of the more frequently used options in the Window and Spectra menus.
5. The buttons in this box control what a spectrum looks like. These buttons provide shortcuts to some of the most frequently used options in the Spectrum menu and the spectrum properties dialog.
6. This set of short cut buttons allows you to create various graphical objects and to perform integrations. Most of these buttons don't have corresponding menu entries.

Take some time to explore the Xamine GUI as the software has quite a bit of functionality that we will not describe in this document.

Subdividing the display

Xamine can display up to 100 spectra. This is accomplished by:

1. Using the geometry button to subdivide the display area into a rectangular array of row and columns.
2. using the Display and Display+ buttons to place spectra into the display area.

Click on the Geometry button (note that any spectra that are displayed are removed from the display whenever the geometry is changed). You will see the following dialog. Note that all Xamine dialogs are non-modal, if you have the screen space and will be interacting with a dialog several times feel free to leave it posted on the screen.

To set a geometry, use the radio buttons to select the number of rows and columns you want. Click ok to accept and dismiss the dialog (click apply to accept and keep the dialog posted). click Cancel to do nothing.

The SpecTcl display area is now divided as you have requested. Each box in the display area will be referred to as a pane. One pane is always rendered to look like it is pressed in. This pane is called the selected pane. All operations on single spectra are performed on the selected pane.

Single clicking on pane selects it. Double clicking a pane selects it and toggles between zoomed and unzoomed display. Zoomed display only displays the selected pane. Unzoomed displays them all. The zoom checkbox can also be used to flip back and forth between zoomed and unzoomed.

Displaying spectra

Once you have selected a pane geometry, you will want to display spectra in the panes of this geometry. To do this you will:

• Select the pane you want to "fill."
• Click on either the Display or Display+ buttons to bring up the Spectrum Choice dialog.
• Select a spectrum from that dialog.
• Click Apply or Ok to accept. Note that double clicking the spectrum name also performs the default action (Ok for Display and Accept for Display+).

The differences between the Display and Display+ buttons are:

• The default action for the Display button dialog is Ok, while that of the Display+ button dialog is Apply.
• when the Display+ button's dialog is "applied", the selected pane will be changed. This allows you to quickly fill the panes in a geometry.

Setting the characteristics of a spectrum

You will often want to modify the characteristics of a spectrum so that you can see the features you are interested in. This section will describe how to set the characteristics that are available on the short cut buttons.

Updating spectra

To update the selected pane, click the Update Selected button. To update the contents of all panes, click the Update All button. A periodic update rate can be set using the properties dialog in the Spectra->Properties menu entry and the Options->Update Rate... menu entry.

Changing the full scale

To change the full scale of a spectrum, use the + and - buttons. These buttons rescale the spectrum to move the peak height in the direction implied by the button label. Thus + actually decreases the full scale and - increases the full scale.

Expanding and unexpanding

Given a pane that is displaying a spectrum, you can display a region of interest within that spectrum using the Expand button. A region of interest is a slice of the spectrum between lower and upper limits for a 1-spectrum. For a 2-d spectrum, a region of interest is the interior of a rectangle defined by two points on one of its diagonals.

Click on the Expand button. Xamine will display the expand dialog.

Click the limits of the region of interest in the spectrum. If you click on a spectrum that is not selected, any points you have acceped are lost and the new spectrum is selected. Click on Ok or Apply to accept your points and display only the region of the spectrum between them.

Once expanded, you can re-display the entire spectrumby clicking on the Unexpand button.

Integrating regions of a spectra

You can integrate regions of interest on 1 or 2 dimensional spectra. The Xamine nomenclature for a region of interest is Summing Region. Summing regions are a kind of graphical object that is created on a spectrum pane and remains in place until deleted. Summing regions are associated with a spectrum and will be displayed any time that spectrum is displayed in a pane.

To accept a summing region:

• Click the Summing Region button.
• The Grahical input dialog will be displayed.
• Click in the points of the summing region on the spectrum.
• Click ok, or accept, to accept the summing region.

To perform an integration, click on the Integrate button. A text box will pop up to show the results of the integrations on all summing regions and elligible gates in the selected spectrum. If you do another integration without dismissing the text box, the results will be appended to the text box so that you can compare them.

Note that if you eventually decide to use gates, Integrate will also integrate cuts and contours.

Printing spectra

Spectra can be printed. Use the File->Print... menu to bring up the print dialog. Fill it in as desired (you may need to ask NSCL staff which printers are available and best for you). Click ok to dismiss and print.

Saving and restoring your setups

Normally you will create several geometries, with different sets of spectra. Each of these (geometry + layout) is called a Window definition. For example, you may have one window definition that displays the key ppac spectra, and another that displays the scintillator spectra.

It would be painful to have to re-create each window definition every time you needed it. Therefore, Xamine allows you to save window definitions to file. Saved window definition files can then be re-loaeded.

To save a window definition file:

• Click the Window->Write Configuration.. menu entry.
• The file selection dialog box will pop up.
• Choose the directory and name of the file you want to write to. To overwrite an existing file, simply double click it.
• Click Ok to accept the filename and create the file.

To restore a window definition file:

• Click the Window->Read Configuration.. menu entry.
• The file selection dialog box will pop up.
• Choose the directory and name of the file you want to write to by simply double clicking it.

Using Xamine