Glossary

A-D

Analog to Digital

ACS

Advanced Camera for Surveys

ABMAG

–2.5 log (F_ν) – 48.60 where F_ν is the flux from the source in erg/cm²/s/hz

APT

Astronomer’s Proposal Tool. Used to construct Phase I and Phase II observing proposals: https://www.stsci.edu/scientific-community/software/astronomers-proposal-tool-apt

BOP

Bright-Object Protection

CALSTIS

STIS calibration pipeline software: https://stistools.readthedocs.io/en/latest/calstis.html

CCD

Charge Coupled Device. Solid-state photon counting device

CDBS

Calibration Data Base. System for maintaining reference files and tables used to calibrate HST observational datasets.

CIM

Calibration insert mechanism

CP, CfP

Call for Proposals

CR

Cosmic ray

CR-SPLIT

Division of a CCD exposure into shorter exposures to be used for cosmic ray rejection

CTE

Charge Transfer Efficiency

CTI

Charge Transfer Inefficiency, CTI = 1 – CTE

CVZ

Continuous Viewing Zone.  A range of target declinations for which full-orbit observations may be obtained (without Earth occultation).

DQ

Data Quality.  DQ flags in the data files indicate various potential or actual problems with the data.

DHB

Data Handbook: https://hst-docs.stsci.edu/stisdhb

DN

Data Number

ETC

Exposure Time Calculator. ETCs are Web based tools, which can be accessed at https://etc.stsci.edu.

ERO

Early Release Observations

FGS

Fine Guidance Sensors

FITS

Flexible Image Transport System. A generic IEEE and NASA defined standard file format used for storing image data.

FOC

Faint Object Camera

FOS

Faint Object Spectrograph

FOV

Field of View

FSW

Flight Software

FTP

File Transfer Protocol. Basic tool used to retrieve files from a remote system. Ask your system manager for information about using FTP.

FUV

Far ultraviolet (~912–2000 Å)

FWHM

Full Width at Half Maximum

GALEX

Galaxy Evolution Explorer

GHRS

Goddard High-Resolution Spectrograph

GO

General Observer

GSC

Guide Star Catalog

GTO

Guaranteed Time Observer

Help Desk

Facility for getting help on HST related topics: http://hsthelp.stsci.edu or help@stsci.edu.

HITM

Hole in the Mirror.  Part of the optical path for some calibration lamps.

HSP

High-Speed Photometer

HST

Hubble Space Telescope

HUT

Hopkins Ultraviolet Telescope

ICD

Interface control document. Defines data structures used between software or systems to ensure compatibility.

IDT

Instrument Definition Team

IHB

Instrument Handbook

IR

Infrared

IRAF

Image Reduction and Analysis Facility. The environment in which ­STSDAS operates (no longer supported).

IS

Instrument Scientist

ISR

Instrument Science Report

IUE

International Ultraviolet Explorer

K

Degree Kelvin

LMC

Large Magellanic Cloud

LSF

Line spread function

MAMA

Multi-Anode Microchannel Array.  STIS uses MAMA detectors for FUV and NUV observations.

Barbara A. Mikulski Archive for Space Telescopes. A repository for data from HST, JWST, and other missions: https://mast.stsci.edu/

MCP

Microchannel Plate

MSM

Mode-Selection Mechanism

ND

Neutral density

NIR

Near infrared

NICMOS

Near-Infrared Camera and Multi-Object Spectrograph

NUV

Near ultraviolet (~2000–4000 Å)

OSS

Observation Support System

OTA

Optical Telescope Assembly

OTFR

On-the-Fly Re-processing. Re-processing of data, using the most recent/appropriate reference files and software, when the data are requested from the archive.

PC

Program Coordinator

Peakdown

Movement of a target along a slit to center it under an occulting bar.

Peakup

Movement of a target in one or both directions to center it in a slit.

Phase I

A proposal for observing time on HST

Phase II

An approved HST proposal; includes detailed instructions for how a program is to be executed

PI

Principal investigator

PSF

Point-spread function

QE

Quantum efficiency

QEH

Quantum efficiency hysteresis

QSO

Quasi-stellar object

RA

Right ascension

reference file

Data file containing STIS parameters or calibration information which is used by the pipeline

rms

Root mean square

SAA

South Atlantic anomaly.  A region of enhanced background radiation.  STIS is not used when the orbital path of HST passes through the SAA.

SIM

Space Interferometry Mission

SITe

Scientific Image Technologies; company that designed the STIS CCD

SM4

Servicing mission 4.  Servicing mission in which STIS operations were restored

SMOV

Servicing Mission Observatory Verification

S/N, SNR

Signal-to-noise ratio

ST-ECF

Space Telescope European Coordinating Facility

STAN

Space Telescope Analysis Newsletter

stenv

Environment for HST and JWST pipelines and (most) packages formerly available through astroconda: https://stenv.readthedocs.io/en/latest/

STIS

Space Telescope Imaging Spectrograph

stis_cti

Pixel-based CTI correction software for the STIS CCD: https://www.stsci.edu/hst/instrumentation/stis/data-analysis-and-software-tools/pixel-based-cti

STMAG

STScI magnitude system; –2.5 log (F_λ) –21.10 where Fλ is the flux from the source in erg/cm²/s/Å

STScI

Space Telescope Science Institute

STSDAS

Space Telescope Science Data Analysis System. The complete suite of IRAF data analysis and calibration routines used to process HST data (no longer supported).

SV

Science verification. Process of taking observations that can be used for HST instrument calibration.

synphot

Synthetic Photometry software package: https://synphot.readthedocs.io/en/latest/

TAC

Telescope Allocation Committee

TAS

Target Acquisitions Simulator: https://stistarg.readthedocs.io/en/latest/

TDS

Time-dependent Sensitivity

TIR

Technical Instrument Report

URL

Uniform resource locator. Address for websites.

UV

Ultraviolet

WF/PC

Wide Field/Planetary Camera

WFPC2

Wide Field Planetary Camera-2. Replacement for WF/PC installed during first servicing mission of December 1993.