CHAPTER 1:
Introduction
The Advanced Camera for Surveys (ACS), a third-generation
instrument, was installed in the Hubble Space Telescope during Servicing
Mission 3B (http://www.stsci.edu/hst/HST_overview/servicing_missions)
on March 7, 2002. Its primary purpose is to increase HST imaging
discovery efficiency by about a factor of 10, with a combination of detector
area and quantum efficiency that surpasses previous instruments.
ACS has three independent cameras that provide wide-field, high
resolution, and ultraviolet imaging capabilities respectively, using a broad
assortment of filters designed to address a large range of scientific goals. In
addition, coronagraphic, polarimetric, and grism capabilities make this a
versatile and powerful instrument.
The ACS Instrument Handbook, which is maintained by the
ACS-WFPC2 Team at STScI, describes the instrument properties,
performance, operations, and calibration. It is the basic technical reference
manual for the instrument, and should be used with other documents (listed
in Table 1.1) for writing Phase I proposals, detailed Phase II programs, and
for data analysis. (See Figure 1.1).
The documents in Table 1.1 can be downloaded from the ACS STScI
Web site, http://www.stsci.edu/hst/acs. Paper copies can be requested by
sending a message to help@stsci.edu or by calling 410-338-1082.
European users may also contact the Space Telescope European
Coordinating Facility (ST ECF) at Garching, Germany (+49-89-320
06-291, stdesk@eso.org).
1
2
Chapter 1: Introduction
Table 1.1: Useful documents
Purpose
Document or resource
General
observatory
information
HST Primer
http://www.stsci.edu/hst/proposing/docs/proposing/documents/cp/primer.pdf
Phase I
proposals
Proposing Overview
http://www.stsci.edu/hst/proposing/docs/proposingOverview
Call for Proposals
http://www.stsci.edu/hst/hst/proposing/documents/cp/cp_cover.html
Phase II
programs
Phase II Proposal Instructions
http://www.stsci.edu/hst/programs/hst/proposing/docs/p2pi.html
Astronomer's Proposal Tool (APT) for Phase II preparations
http://apt.stsci.edu/
Data analysis
ACS Data Handbook
http://www.stsci.edu/hst/acs/documents/handbooks/DataHandbookv4/ACS_longdhbcover.html
Dither Handbook
http://www.stsci.edu/instruments/wfpc2/Wfpc2_driz/dither_handbook.html
Space Telescope Analysis Newsletter
http://www.stsci.edu/hst/acs/documents/isrs/hst/acs/documents/newsletters
Instrument Science Reports
http://www.stsci.edu/hst/acs/documents/isrs
Calibration and Pipeline Information
http://www.stsci.edu/hst/Post-observation
Instrument
specific
ACS Web page
http://www.stsci.edu/hst/acs
ACS Forum
http://forums.stsci.edu/phpbb/viewforum.php?f=14
3
Figure 1.1: Handbook roadmap for proposal preparation.
Review special
Cycle 17 issues for ACS.
Chapter 2
Obtain overview of ACS
capabilities and operation.
Information on
ACS detectors.
Chapter 3
Select imaging &
estimate exposure times.
Chapter 4
Select coronagraphy,
polarimetry, or grisms &
estimate exposure times.
Chapter 5, Chapter 9
Chapter 6
Detailed exposure
time calculations?
Chapter 9
Additional reference
material.
Chapter 10
Select data-taking
mode.
Chapter 7
Information on
ACS calibrations.
ACS Web site
Determine overheads and
calculate Phase I orbit time
request.
Chapter 8,Chapter 9
4
1.1
Chapter 1: Introduction
Symbols Test
Test section for symbols
Table 1.1: Symbol Table
alphbetic
(symbol)
α
shift
(symbol)
∞ Α,
β
other,
shift
(symbol)
just other,
shift
just alt
(option)
(does not
work on
virtual pc)
fm 6 unix
x11
1, !
1, !
1, ¡
1, ℑ
2, ≅
2, @
3, £
3, ≤
alt (option)
with symbol
fm 6 on
unix
χ
Χ
3, #
3, #
4, ¢
4, ′
δ
∆
4, ∃
4, $
6, §
6, ⁄
5, %
5, %
7, ¶
7, ƒ
6, ⊥
6, ^
8, •
8, ∞
γ
7, &
7, &
9, ª
9, ≈
η
8, ∗
8, *
0, º
0, …
ι
9, 0 ( )
9, 0 ( )
-, –
-, ∠
ϕ
− ,_
-,_
r, ®
r, ♦
κ
=,+
=,+
t, †
t,
;.:
;.:
y, ¥
y, ×
µ
∋ ,∀
',"
o, ø
o, ↵
ν
,<
,<
[,“
[,
o
.>
.>
\,«
\,∩
π
/?
/?
a, å
a,
θ
[{
[{
s, ß
s, ♣
ρ
]}
]}
g, ©
g, ♥
σ
∴ |
\|
h, °
h, 
τ
 ∼
` ~
l, ¬
l, ℜ
;,…
;,⊃
ε
φ
λ
υ
Φ
Λ
Symbols Test
Table 1.1: Symbol Table
alphbetic
(symbol)
shift
(symbol)
ϖ
ω
ξ, ψ , ζ
x, y, z
Ω
Ξ, Ψ , Ζ
other,
shift
(symbol)
just other,
shift
just alt
(option)
(does not
work on
virtual pc)
fm 6 unix
x11
alt (option)
with symbol
fm 6 on
unix
’, æ
’, 
c, ç
c,
m, m
³³³
m, µ
5
6
Chapter 1: Introduction