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Last modified: 15 December 2008
Hardcopy (PDF): A4 | Letter

Chandra/CIAO Dictionary


Chandra and CIAO use a number of specialized terms, some of which are common in X-ray astronomy data analysis, but not used elsewhere, and some of which are specific to CIAO.

Here we provide a dictionary of these terms. We have provided links to more information in the CIAO webpages, on the CXC site in general, and in external webpages as appropriate, making the dictionary a handy place from which to explore. Help on the CIAO tools is available from the ahelp documentation page.



A B C D E F G H I L M O P Q R S T V W X Y Z


A
ACIS Background
ACIS: Advanced Camera for Imaging and Spectroscopy
ADU
Afterglow
Alternating Exposure Mode
APEC: Astrophysical Plasma Emission Code
APED: Astrophysical Plasma Emission Database
ARD: Analysis Reference Data
ARF: Auxiliary Response File
asol
Aspect / Aspect Solution
ATOMDB: Atomic Database
B
Bad Pixels
BI: Backside Illuminated
C
CALDB: Calibration Database
Chandra
ChaRT: The Chandra Ray Tracer
ChIPS: Chandra Image and Plotting System
CIAO: Chandra Interactive Analysis of Observations
Continuous Clocking (CC)-mode for ACIS
Coordinates
CP: Custom Processing
CTI: Charge Transfer Inefficiency
CXC: Chandra X-ray Center
D
Data Model (DM)
Dither
ds9
DTCOR
E
Effective Area
Electron Proton Helium Instrument (EPHIN)
Energy
Event
evt
EXPOSURE and EXPOSURn
Exposure Maps
EXPTIME
F
FEF: FITS Embedded Function
FI: Frontside Illuminated
Filter Window (filtwin)
Firstlook
FITS: Flexible Image Transport System
FLSHTIME
flt
G
Grade (Event Grade)
GTI: Good Time Intervals
GUI
GUIDE: Grating User Interactive Data Extension
H
HETG/HETGS: High Energy Transmission Grating (Spectrometer)
HRC: High Resolution Camera
HRMA: High Resolution Mirror Assembly
I
img
Instrument Maps
ISIS
L
LETG/LETGS: Low Energy Transmission Grating (Spectrometer)
Levels (in Standard Data Processing)
LIVTIMEn and LIVETIME
LSF: Line Spread Function
M
Mask File
MDL: Model Descriptor List
mtl / MTL: Mission Time Line
O
OBC: On-Board Computer
OBI: Observation Interval
Observation Times
ObsID: Observation Id
OGIP: Office for Guest Investigator Programs
OIF: Observation Index File
ONTIME and ONTIMEn
osol
P
PCAD: Pointing Control and Determination system
PHA keywords
PHA: Pulse Height Amplitude
PI: Pulse Invariant
Pileup
Pitch
Pixlib
Platform
Prism
PSF Libraries
PSF: Point Spread Function
Q
Quantum Efficiency (QE)
Quantum Efficiency Uniformity (QEU)
R
Regions
RMF: Redistribution Matrix File
S
S-Lang
SDP: Standard Data Processing
Sherpa
SIM: Science Instrument Module
src
Stacks
Status Bits
Streak Events
Subspace / Data Subspace
T
TCD: Transforms, Convolutions and Deconvolutions
TIMEDEL
V
V&V: Verification and Validation
Virtual Columns
VTP: Voronoi Tessalation and Percolation
W
WCS: World Coordinate System
WMAP: Weight Map
X
X-rays
Y
Yaw
Z
z
Hardcopy (PDF): A4 | Letter
Last modified: 15 December 2008


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