Mission definitions included in MARXS

This section describes mission profiles included in MARXS. Currently, this is very limited but we expect this to grow in the future and we welcome contributions.

Chandra

MARXS includes a simplified definition for the Chandra X-ray observatory, which includes ACIS and the HETG, but even for those instruments details are missing, e.g. the ACIS contamination and quantum efficiency, and for the HETG the diffraction efficiency. The purpose if this module is a use in examples in this documentation. Please use classic MARX for any scientific study or Chandra proposal.

Reference/API

marxs.missions Package

marxs.missions.chandra Package

Geometry and operations of the Chandra Observatory.

This module provides the optical elements on the Chandra Observatory.

Warning

Currently incomplete.

Missing:

• a lot

Incomplete:

• Grating order efficiencies are the same for every order.

Some spacecraft properties are defined in module attributes, others are read from reference files in the CALDB (or the files shipped with classic MARX). Properties that are very easy to define and that are very unlikely to ever change (e.g. the mapping of ACIS chip number to chip name) are set in this module. That makes is easier to see where the numbers come from and thus helps for users who look at this module as an example of how to build up complex marxs setups.

Classes

ACIS(chips, **kwargs)	The ACIS instrument
Aperture(**kwargs)	Chandra opening aperture of four rings above the mirror shells.
Chandra(**kwargs)	Main class representing the Chandra X-ray observatory
HETG(**kwargs)	Define a new MARXS element.
LissajousDither(**kwargs)	Lissajous dither pattern with adjustable parameters.

Class Inheritance Diagram

marxs.missions.mitsnl.catgrating Module

Gratings made by the MKI Space Nanotechnology Laboratory

The MIT Kavli Institute for Astrophysics and Space Research Space Nanotechnology Laboratory produces elements for astronomical instruments in space. One particular field of research are critical angle transmission (CAT) gratings, see e.g. Heilmann et al. (2015)

Functions

catsupportbars(photons)

Metal structure that holds grating facets will absorb all photons that do not pass through a grating facet.

Classes

InterpolateEfficiencyTable(tab[, k])	Order Selector for MARXS using a specific kind of data table.
QualityFactor([qualityfactor])	Scale probabilities of theoretical curves to measured values.
L1([l1_dims])	A CAT grating representing only the L1 structure
L2Abs([l2_dims])	L2 absorption and shadowing
L2Diffraction([l2_dims])	Very simple approximation of L2 diffraction effects.
CATL1L2Stack([l1_dims, l2_dims, ...])	SNL fabricated CAT grating
NonParallelCATGrating(**kwargs)	CAT Grating where the angle of the reflective wall changes.

Class Inheritance Diagram