In this section, we will guide new users through the homepage, which contains valuable information and helpful links, as well as the workbook page where users can create, share, and organize workbooks.

Homepage

Upon accessing the new ETC, users are presented with the homepage which contains a variety of helpful information and links.  The image below displays the homepage, and highlights and numbers the individual sections, each of which is explained below.

1. In this section you will find the buttons that take you to the ETC.  There are several ways of accessing the ETC. 

• The "Quick Start" button takes you directly into the ETC and will take users on a guided tour of the interface, showing you how to create a calculation.  This is recommended for first time users.
• The "Create User" button is where new users should go to set up a new account, which is required in order to save and share workbooks with other users.
• The "Login" button is the standard entry point.  After logging in, you will be taken to the workbook page where you can create, share, and organize your workbooks.
• The "Work Anonymously" button also takes you to the workbook page, but without logging in, you will not be able to save or share workbooks with collaborators.

2.  The "News" pane contains information about updates and potential downtime for the ETC.

3.  The "Help" pane contains links to videos and documentation that helps new users understand and take advantage of all of the features of the ETC.

4.  The "Readme" pane lists information about the performance and accuracy of the ETC, as well as recommendations about which browsers should be used (Firefox, Chrome, and Safari).

Workbooks

Once users are logged in, they are taken to the page where they can access all of their own saved workbooks.  Workbooks are collections of calculations stored together in a list.  Users can create, organize, and share their workbooks with other users from this page.

1.  The first pane is the "Available Workbooks" pane.  This lists all of the previously created workbooks that can be loaded.  In this case, the first row is not a workbook, but a folder.  Users can move workbooks into folders using the '[move]' link in the 'Options' column.  Folders can also be nested.  Workbooks can be opened by clicking the '[load]' link in the 'Actions' column which will take them to the list of calculations.

2.  At the bottom of the Available Workbooks pane are the buttons for creating new workbooks and folders, and the buttons for loading sample workbooks. 

The "Sample Workbooks" pulldown button contains a list of example calculations for each of the available HST observing modes.  The "Example Science Program Workbooks" pulldown button contains workbooks which are associated with documentation walking users through the process of creating detailed calculations.

3.  The second pane is used for sharing workbooks with collaborators.  When a workbook is highlighted, this pane will display a list of users which currently have access to the workbook.  To share the workbook, simply enter the email address associated with your collaborator's ETC account in the "User Email" text box, then click the "Add User By Email" button.  This will add a row to the table with their name.  As the owner of a workbook, you can then choose which privileges this new user will have: read, write, grant, and revoke.  If all of these privileges are unchecked, the workbook will no longer be shared with this user, and their name will be removed from the list.

In this section, the process of creating a new calculation, and various new features are shown.

Calculations 

1.  The first pane lists all of the calculations that are stored in this workbook.  Clicking on one of the existing calculations highlights it which will allow the calculation to be edited, as well as displaying information about that calculation in the other panes.  New calculations can be added (up to the workbook limit of 50 calculations) by using dropdown buttons for the desired HST instrument (ACS, COS, STIS, and WFC3).  The dropdown will show a list of the currently supported observing modes for this instrument. 

In the current alpha version, not all modes supported by the legacy ETC are available, but they will be included by the full ETC release.  Clicking on the desired observing mode will add a new default calculation to the list, which can then modified to suit your goals.

2.  The second pane allows you to configure the calculation.  The options are organizes into a series of tabs at the top of the pane:

• The 'Scene' tab allows users to configure the sources being observed.  This topic is one of the largest differences between the new and legacy versions of the ETC and is explored more thoroughly in the next section of the poster.
• The 'Backgrounds' tab contains the settings which allow users to scale the various components of the background.
• 'Instrument Setup' contains the instrument specific options, such as filters, dispersers, and slits.
• 'Detector Setup' is where users will specify if they are calculating SNR for a given time, or time for a desired SNR.  Additionaly, settings like gain, postflash, and number of exposures are specified here.
• 'Strategy' is where users can specify the settings related to the extraction strategy, such as the size of the aperture and whether it's specified in arcseconds or encircled energy.  Because the new ETC allows multiple sources to be defined for a single calculation, users can also specify where in the scene the aperture is placed in this tab.

3.  The third pane, 'Images', is where users can view the resulting images from the selected calculation.  The images include the 2D SNR map, the per pixel count rate, the distribution of saturated pixels, and the per pixel maximum exposure time before each pixel saturates.  Users can zoom in and pan around the image, and can download them as png files.  These images are also included as fits files in the tar file available for download in the ‘Downloads’ tab in the ‘Reports’ pane (pane 5).

4.  The 'Plots' pane allows users to visualize the flux, background, and SNR (as a function of wavelength or time) of multiple calculations in the workbook together.  Users can take advantage of the ‘Copy Calculation’ and ‘Expand’ features of Pandeia to create multiple calculations which vary a subset of parameters, then compare them all in these plots to determine the optimal setup.  To compare multiple calculations against each other by clicking the check boxes next to each calculation.

5.  The 'Reports' pane contains the quantities calculated by the engine, including SNR, extracted flux, detector and instrument settings, extraction settings, and background counts.  Other tabs in this pane report errors and warnings.  In the event that the calculation produced warnings or errors, these tabs will be shown in red.  The final tab in this pane is ‘Downloads’, where users can download the results of the calculation.  The downloaded tar file includes the inputs stored in a json file, a fits file containing the observation background, the outputs in the ‘Images’ and ‘Plots’ tabs, and the data cubes.

Outside of the panes, at the top of the page is a drop down menu called 'Expand':

This allows users to duplicate calculations which vary only over the listed parameter.  In this case, users can expand of 'filters'.  Selecting this will then create multiple copies of the selected calculation, one with each of the available filters selected.  This allows users to quickly explore the parameter space and determine the optimal setup for the observation.

Another new feature that allows users to quickly explore parameter space is scripting.  The new ETC features an engine which is scriptable in python.  Users can setup calculations in python and, for example, loop over any of the available parameters to programatically explore the parameter space.  Information, including tutorials, on scripting the engine can be found here.  While this documentation is written for scripting JWST calculations, users can specify the telescope and observing modes to fit their needs.