MAXI/GSC Detector Definitions (gdt.missions.maxi.gsc.detectors)

GSC Fields of View

The GscFov class contains the naming and orientation of the two fields-of-view (FOVs) of the the Gas-Slit Camera on-board MAXI. In general, the two FOVs are oriented 90 degrees from one another and can be described as an approximated rectangular box with a width of ~3 degrees and a length of ~160 degrees. One FOV is pointed in the direction of the ISS motion in orbit (the Horizontal, or GSC-H) and the other FOV is pointed at the zenith (GSC-Z). The naming, pointing, and bounding box of the FOV is contained within the GscFov class.

We can easily retrieve a FOV definition by using standard “dot” notation:

>>> from gdt.missions.maxi.gsc.detectors import GscFov
>>> GscFov.H
<GscFov: H>

We can retrive the string name of the FOV:

>>> GscFov.H
'H'

As well as the full name of the FOV:

>>> GscFov.H.full_name
'GSC-H'

Since the GscFov class inherits from the Detectors base class, we can also retrieve the pointing information of the FOV in the MAXI frame:

>>> # FOV azimuth, zenith
>>> GscFov.from_str('Z').pointing()
(<Quantity 0. deg>, <Quantity 180. deg>)

>>> # detector elevation
>>> GscFov.from_full_name('GSC-Z').elevation
<Quantity -90. deg>

We can also retrieve the bounding box of the FOV:

>>> GscFov.Z.fov
[(268.5, 100.0), (91.5, 100.0), (88.5, 100.0), (271.5, 100.0), (268.5, 100.0)]

GSC PSPC Detectors

Each GSC FOV is covered by 6 Position Sensitive Gas Proportional Counters (PSPCs), each of which are given names and produce data. The GscDetectors class tracks the information of these detectors in the same was as GscFov does for FOVs.

To get a list of the GSC detectors, we can iterate over the GscDetectors class:

>>> from gdt.missions.maxi.gsc.detectors import GscDetectors
>>> print([detector.name for detector in GscDetectors])
['HA0', 'HA1', 'HA2', 'HB0', 'HB1', 'HB2', 'ZA0', 'ZA1', 'ZA2', 'ZB0', 'ZB1', 'ZB2']

And we can get the list of detectors that only belong the Horizontal FOV:

>>> GscDetectors.h_detectors()
[<GscDetectors: HA0>,
 <GscDetectors: HA1>,
 <GscDetectors: HA2>,
 <GscDetectors: HB0>,
 <GscDetectors: HB1>,
 <GscDetectors: HB2>]

And we can test if a particular detector is in the zenithal FOV:

>>> print([det.is_z_detector() for det in GscDetectors])
[False, False, False, False, False, False, True, True, True, True, True, True]

Reference/API

gdt.missions.maxi.gsc.detectors Module

Classes

GscDetectors(value[, names, module, ...])	The MAXI GSC detectors.
GscFov(value[, names, module, qualname, ...])	The MAXI GSC detector fields of view for the two GSC instruments: GSC-H (Horizontal) and GSC-Z (Zenith).

Class Inheritance Diagram