AASTeX Author Guide

This is the comprehensive guide to preparing manuscripts using the latest AASTeX classfile. An AASTeX version of this document is also available in the macros distribution package.

1 Introduction

The American Astronomical Society (AAS) has developed a markup package to assist authors in preparing manuscripts intended for submission to its journals.

The most important aspect of the AASTeX package is that it defines the set of commands, or markup, that can be used to identify the structural elements of manuscripts. When articles are marked up using this set of standard commands, they may then be submitted electronically to the editorial office which aids both the peer review ingest and production processing.

This guide contains basic instructions for creating manuscripts using the latest AASTeX markup package (version 6.0). Authors are expected to be familiar with the editorial requirements of the journals so that they can make appropriate submissions; they should also have a basic knowledge of LaTeX-for instance, knowing how to set up equations using LaTeX commands.

Authors who wish to submit manuscripts electronically to the ApJ or AJ are strongly encouraged use the latest AASTeX markup package as described in this guide. Proper AASTeX markup will speed the ingest process at submission by via the proper extraction of author information from the manuscript and reduce errors during production.

2. AASTeX Article Markup

This section describes the commands in the AASTeX package that an author might enter in a manuscript that is being prepared for electronic submission. The commands will be described in roughly the same order as they would appear in a manuscript. The reader will also find it helpful to examine the example files that are distributed with the package. Authors are also reminded to review the instructions to authors and electronic submissions guidelines prior to manuscript submission.

2.1 Preamble

In LaTeX manuscripts, the preamble is that portion of the file before the \begin{document} command.

2.1.1 Getting Started

The first piece of markup in the manuscript declares the overall style of the document. Any commands that appear before this markup will be ignored.

\documentclass{aastex}

This specifies the document class as aastex with the default style (onecolumn). The manuscript copy produced by this style is a tight typeset, single column format. Other substyles are available. They are discussed in greater detail in Section 3.

2.1.2 Defining New Commands

AASTeX allows authors to define their own commands with LaTeX's \newcommand. (Authors should not use the plain TeX \def command in AAS journal submissions.) Authors' \newcommand definitions must be placed in the document preamble.

In general, author-defined commands that are abbreviations or shorthands are acceptable and can be easily handled by journal offices and publishers during data conversion; for example:

\newcommand{\grb}{gamma ray burst}
\newcommand{\bHa}{Broad line H{\alpha}}

However, abbreviations that attempt to define new symbols by using LaTeX commands for repositioning text tend to cause problems in the publication process and should be avoided. In particular, author-defined commands that use any of the commands listed below are apt to cause problems during data conversion.

\hskip, \vskip, \raise, \raisebox, \lower, \rlap, \kern, \lineskip, \char, \mathchar, \mathcode, \buildref, \mathrel, \baselineskip

Consequently, authors are strongly discouraged from using them.

Extra symbols are defined for AASTeX, some specifically for an astronomical context, others more broadly used in math and physics. In particular, the AMS has additional symbol fonts that are available in a standard LaTeX package (amssymb). All of these symbols are depicted in the additional symbols tables supplied with the package and on the AASTeX Web site.

Before defining a new symbol command, authors are advised to consult these tables to see whether the symbol they need already exists. If it does, they should use the corresponding markup command. Authors should not redefine existing command names. When one of these commands is encountered in an electronic manuscript submitted to a journal, an author's redefinition will be ignored and the originally-defined command used.

2.1.3 Optional Editorial and Copyright Information

A number of markup commands are available for to timestamp important dates during the peer review process to document the publication history. These commands are not required as this information is pulled from the peer review database after acceptance and inserted by the publisher during production. Authors may find these commands useful for arXiv submissions.

\received{receipt date}
\revised{revision date}
\accepted{acceptance date}
 
\ccc{code}
\cpright{type}{year}

Copyright information is not required but can be specified with the commands \cpright and \ccc. The type of copyright and the corresponding year are given in \cpright. Valid copyright types are as follows.

AAS Copyright assigned to the AAS
Crown Crown copyright applies
none No copyright can be claimed

The copyright type is case sensitive, so the type string must be entered exactly as given above.

The Copyright Clearing Center code may be given in the \ccc command. The code is taken as regular text, so any special characters, notably "$," must be escaped as appropriate.

2.1.4 Short Comment and Water marking on Title Page

Authors who wish to include a short remark on the title page, such as the name and date of the journal to which an article has been submitted, may do so with the following command.

\slugcomment{text}

These comments appear at the upper right corner of the title page.

An optional water mark can be superimposed over the title page using the following commands.

\watermark{text}
\setwatermarkfontsize{dimension} 

The first command will print text in a light gray color on the title page running diagonally from the bottom left to the top right. The font size can also be specified by the second command, e.g. 2in, to obtain the appropriate size. Authors may have to experiment with the wording and font size to obtain a desired result. The water mark information is not used during production but authors might find it useful to identify drafts or preprints.

2.1.5 Running Heads

Authors may supply optional running head information using the following commands.

 \shorttitle{text} 
 \shortauthors{text}

Two different kinds of data are generally supplied in running heads. A shortened author list (last names, possibly truncated as "et al.") appears at the top of even numbered pages while an abbreviated form of the manuscript title appears on the top of odd numbered pages. The information in these commands will be passed through to copy editing staff for inclusion in the published version but only the short authors information will be shown in the html.

The information contained within these commands should be brief. A good rule of thumb is to limit the list of authors to three or else use "et al.," and to limit the short form of the title to 40-45 characters. The editors may choose to modify the author-supplied running heads.

2.2 Starting the Main Body

The preamble is a control section. None of the markup that appears in the preamble actually typesets anything. The author must include a

\begin{document}

command to identify the beginning of the main, typeset portion of the manuscript.

2.3 Title and Author Information

Authors should use the \title and \author commands to specify title and author information and the \affil command to indicate the author's primary affiliation. Each \author command should be followed by a corresponding \affil and optional \email command.

\title{text}
\author{name(s)}
\affil{affiliation}
\affil{address}
\email{e-mail address}
\and 

Line breaks may be inserted in the title with the \\ command. (Long titles will be broken automatically, so the \\markup is not required.) If the title is explicitly broken over several lines, the preferred style for titles in AAS journals is the so-called "inverted pyramid" style. In this style, the longest line is the first (or top) line, and each succeeding line is shorter. The text of the title should be entered in upper case. Footnotes are permissible in titles. Be careful to ensure that alternate affiliations (see below) are properly numbered if a footnote to the title is specified.

Authors' names should be entered in mixed case. Authors can use the LaTeX CJK macro package to include Chinese, Japanese and Korean language support with their names. Names that appear together in the author list for authors who have the same primary affiliation should be specified in a single \author command. Each author group should be followed by an \affil command giving the principle affiliation of those authors. Physical and postal address information for the specified institution should be included with \affil. The address can be broken over several lines using the \\ command to indicate the line breaks. Usually, however, postal information will fit on one line. When there is more than one \author command, the final one should be preceded by the \and command.

Authors often have affiliations in addition to their principle employer. These alternate affiliations may be specified with the \altaffilmark and \altaffiltext commands. These behave like the \footnotemark and footnotetext commands of LaTeX except that they do not take optional arguments. \altaffilmark is appended to authors' names in the \author list and generates superscript identification numbers. The text for the individual alternate affiliations is generated by the \altaffiltext command.

\altaffilmark{key number(s)}
\altaffiltext{numerical key}{text}

It is up to the author to make sure that each key number in his or her \altaffilmark matches the numerical key for the corresponding \altaffiltext.

Note that the AAS peer review system pulls author information directly out of the submitted LaTeX to populate the database. When the \title, \author, \affil, and \begin{abstract}...\end{abstract} commands are used correctly there is a significant savings during submission for the corresponding author since this information does not have to be entered by hand.

When there is a lengthy author list, all author names may be specified in a single \author command with affiliations specified using the \altaffilmark mechanism. In these cases, no \affil commands are used, and in print, the affiliations would all be listed in a footnote block at the bottom of the title page.

Another option for long author lists is to limit the number of authors specifically identified with the rest collected under a collaboration header. To limit the number of shown authors and to define a collaboration use the following commands.

\AuthorCallLimit=number of authors shown
\collaborationName{collaboration identifier}

The first command will only show the specified number of \author commands, e.g. if \AuthorCallLimit=3 then only the authors provided in the first three \author commands will be displayed. When the number of authors is limited the \collaborationName command must also be included. As an example, \collaborationName{Kepler Science Team} would produce "(and the Kepler Science Team Collaboration)" after the nth author.

Note that these author limiting commands are only meant to be used to make lengthy author lists more managable for pdf copies during peer review. Authors are still required to include all authors and affilation information with the corresponding commands outlined above. The full set of authors is critical both during peer review and publication.

2.4 Abstract

A manuscript's abstract should be marked with the abstract environment.

\begin{abstract}
abstract text
\end{abstract}

Note that the abstract length is limited to 250 words.

2.5 Keywords

Keywords, or subject headings, are accommodated as a single piece of text.

\keywords{text}

Authors should supply no more than six keywords, specified in alphabetical order. The \keywords command will append "Subject headings: " to the given keywords. The current list of allowed astronomical keywords can be found here

2.6 Author Comments

Authors may make colored notes or comments with the \authorcomment1 command.

\authorcomment1{author text}

This command produces the included text in red. Similar blue and purple text can be produced with the \authorcomment2 and \authorcomment3 commands. The text in any of these commands appears in the manuscript unless the \turnoffedit command is included in the preamble at which point it disappears altogether. While writing an article, authors can use these commands to mark up sections they are not sure should appear in the final version or provide internal comments to the other co-authors. The three colors provide the ability to identify different co-author comments or document version control.

2.7 Sections

AASTeX supports four levels of section headings.

\section{heading}
\subsection{heading}
\subsubsection{heading}
\paragraph{heading}

Section headings should be given in upper case while subsections are in mixed case. Note that these commands delimit sections by marking the beginning of each section; there are no separate commands to mark the ends.

2.8 Figure and Table Placement

Authors are encouraged to embed their figures and tables around the sections where they are first mentioned. Placing tables and figures after the text was necessary in the past when the article charges were based on the number of print pages. Now article charges are based on more quantifable metrics such as the number of words, tables, and figures, the "readability" of a manuscript is more important, particularly during peer review.

Authors can use the positional placement option on figures and tables to override LaTeX's internal placement logic. The most useful arguments in this option are "h" to place at the approximate location specified in the LaTeX manuscript, i.e. here, "b" place at the bottom of the current page, "t" place a the top of the current page, and "!" force LaTeX to ignore its own determined location. The example,

\begin{figure}[htb!]

tells LaTeX to optimize the figure position by first considering here, then the top of the page, and finally at the bottom. The LaTeX derived position is not considered. Similar positional placement options can be invoked for tables and deluxetables.

If authors can not get LaTeX to optimally place a figure or table they may indicate to the editors the preferred placement of these items by use of the \place* commands.

\placetable{key}
\placefigure{key}

The \place*{key} commands are similar to the \ref command in LaTeX and require corresponding \label commands to link them to the proper elements.

Neither of these commands produce anything in the manuscript. It is strictly a note to the copy editor.

2.9 Acknowledgments

AASTeX supports an \acknowledgments section.

\acknowledgments
acknowledgments text

In the AASTeX styles, acknowledgments are set off from the conclusion of the body with vertical space. Note the acknowledgments command takes no arguments.

2.10 Facilities

To help organizations obtain information on the effectiveness of their telescopes, the AAS has created a group of keywords for telescope facilities. Including a facility keyword list is optional but encouraged. The facilities keyword list is available here.

The facilities list should appear after the acknowledgments section.

Facilities: \facility{facility ID},
\facility{facility ID},
\facility{facility ID}, ... 

As part of the facility ID argument, the author may also include the name of the instrument in parentheses, e.g. facility{HST(WFPC2)} or facility{MMT(Blue channel spectrograph)}. There is no limit to the number of facility keywords that may be included in a manuscript.

2.11 Appendices

When one or more appendices are needed in a manuscript, the point where the main body text ends and the appendix begins should be marked with the \appendix command.

\section{body section}
\appendix
\section{appendix section}

The \appendix command takes care of a number of internal housekeeping concerns, such as identifying sections with letters instead of numerals, and resetting the equation counter. Note that the \appendix command takes no arguments. Sections in the appendix should be headed with \section commands. The default is each appendix section will have a alphabet numbering scheme, e.g. A, B, C, etc.

2.12 Equations

Display equations can be typeset in LaTeX in a number of ways. The following three are probably of greatest use in AASTeX.

\begin{displaymath}
\end{displaymath}
 
\begin{equation}
\end{equation}
 
\begin{eqnarray}
\end{eqnarray}

The displaymath environment will break out a single, unnumbered formula. The equation environment does the same thing except that the equation is autonumbered by LaTeX. To set several formul in which vertical alignment is required, or to display a long equation across multiple lines, use the eqnarray environment. Each line of the eqnarray will be numbered unless a \nonumber command is inserted before the equation line delimiter (\\). LaTeX's equation counter is not incremented when \nonumberis used.

Authors may occasionally wish to group related equations together and identify them with letters appended to the equation number. When this is desired, such related equations should still be set in equation or eqnarray environments, whichever is appropriate, and then grouped within the mathletters environment.

\begin{mathletters}
equation or eqnarray
\end{mathletters}

It is possible to override LaTeX's automatic numbering within the equation or eqnarray environments using

\eqnum{text}

When \eqnum is specified inside an equation environment or on a particular equation within an eqnarray, the text supplied as an argument to \eqnum is used as the equation identifier. LaTeX's equation counter is not incremented when \eqnum is used. \eqnum must be used inside the math environment.

If, as a consequence of the use of \eqnum or \nonumber, LaTeX's equation counter gets out of synch with the author's intended sequence, the counter may be reset to a particular value.

\setcounter{equation}{number}

The equation counter should be set to the number corresponding to the last equation that was formatted; therefore, it is most appropriate for this command to appear immediately after an equation or eqnarray environment. The command must be used outside the math environments.

The eqsecnum style file can also be used to modify the way equations are numbered. See Section 3for details.

2.13 Citations and Bibliography

Bibliographic data supplied by the author in the reference list must conform to the standards of the AAS journals. The specific citation and bibliography styles are outlined here. Fortunately there are two easy options for properly marking citations and formatting reference lists. They are the the standard LaTeX thebibliography environment, and the AASTeX references environment. Authors are strongly encouraged to use thebibliography.

2.13.1 The thebibliography Environment

The preferred method for reference management is to use LaTeX's thebibliography environment, marking citations in the body of the manuscript with \citep or \citet and associating references with them using \bibitem. The \cite-\bibitem mechanism associates citations and references symbolically while maintaining proper citation syntax within the manuscript. In the \bibitem command, the author should specify citation data inside square brackets and a citation key in curly braces for each reference. (The bibitem command is described in detail in the next section.)

   \begin{thebibliography}{dummy}
   \bibitem[cite data]{key} bibliographic data
   . 
   . 
  \end{thebibliography}

Note that the argument dummy to the start command of the environment is not used in the AASTeX package, but it is included to be consistent with the syntax of standard LaTeX. It is acceptable to simply insert an empty pair of curly braces at the end of the \begin{thebibliography} command.

2.13.2 Specifying Bibliographic and Citation Information

AASTeX uses the natbib package for citation management. The natbib package re-implements LaTeX's cite command, offering greater flexibility for managing citations in the author-year form. Specific instructions on how to use natbib is available here.

When using natbib, bibliographic data are defined in bibitem commands.

   \bibitem[author(year)]{key}
     bibliographic data 

The square-bracketed argument of the bibitem contains the author portion of the citation followed by the year set off in parentheses. The parentheses are important-natbib uses them to determine the year portion of the citation-so be sure to include them. The argument key in curly braces is the code name by which the citation is referenced in the text.

When placing citations in the text, the author should use either a citep or a citet command.

\citep{key(s)} \citet{key(s)}

The citep command produces a citation that is entirely set off by parentheses, e.g. "(Cox 1995)," while citet permits the author's name to form part of the text, e.g. "Cox (1995)." The plain LaTeX cite command behaves like citet.

The citation key must correspond to the key in a bibitem command. During processing, information from the square-bracketed argument of the key's bibitem is inserted in the text at the location of the \cite command. Multiple citation keys are separated by commas, e.g., citep{knuth84,cox95,lamport94}.

citep and citet each take optional arguments that specify extra text to be appended to the citation label. Text in the first set of square brackets will appear before the cite while text in the second set will appear after it. For instance, citep[chap. 2]{jon90} would produce the citation "(Jones et al., 1990, chap. 2)," citep[see][]{jon90} would produce "(see Jones et al, 1990)," and citep[see][chap. 2]{jon90}would print "(see Jones et al., 1990, chap. 2)." In addition, the * form of the cite commands will print the full author list instead of the abbreviated form.

The syntax discussed above should be sufficient for the vast majority of cases; however, AASTeX does use the full natbib implementation, so many more syntax options are available.

Authors are also encourage to use reference management software such as BibTex to organize their references and produce correct bibliographies. When using BibTeX a .bst file is need to produce the proper reference output that follows the AAS Journal's format. Authors should use apj.bst when using BibTex with AAS Journal manuscripts.

It is not possible to use \bibitem within AASTeX's references environment ( 2.13.3), nor will \cite commands work properly in the main body if \bibitem commands are absent.

2.13.3 The references Environment

Some authors might prefer to enter citations directly into the body of an article. If so, the references environment may be used to format the reference list. The references environment simply sets off the list of references and adjusts spacing parameters.

\begin{references}
\reference{key} bibliographic data
   . 
   . 
\end{references}

While the references environment remains supported in AASTeX, we anticipate that authors will prefer the stronger capabilities of the standard LaTeX thebibliography commands as extended by natbib.

2.13.4 Abbreviations for Journal Names

AASTeX commands for journal abbreviations have been deprecated. Authors are encouraged to use standard journal abbreviations defined by ADS.

2.13.5 Citing 3rd party data repositories and software

The AAS Journals encourages authors to include data with their articles. In many cases this data can be included with the article, see Section 2.16, but sometimes the data is either too large or too complex to include. In these cases the AAS Journals recommend the author place their data in a trusted 3rd party repository that issues Digital Object Identifiers (DOIs) and properly cite the data in the bibliography. Likewise software and code in persistent repositories should also be linked to the main journal by DOI. A tutorial on how to create citations for external data and software is available here.

2.14 Figures

2.14.1 Electronic Art

If an author wishes to embed graphics in a manuscript, it is necessary that the graphics files conform to either the Encapsulated PostScript (EPS) or PDF standard. Use a package like epstopdf to convert EPS files to PDF if using pdflatex or a mixture of figure formats.

Several commands are available for including EPS/PDF files in AASTeX manuscripts. They should be placed within the figure environment.

\begin{figure}
\figurenum{text}
\epsscale{num}
\plotone{file}
\plottwo{file1}{file2}
\caption{text}
\end{figure}

In the onecolumn style the figure will span the same width of the text. Figures in the twocolumn style will likewise only span the column they are placed in. An author can override this by adding an asterisk, e.g. \begin{figure*}...\end{figure*}, to have a figure span both columns. Authors are responsible for producing figures that are not so small to be unreadable.

When \figurenum is specified inside the figure environment, the text supplied as an argument to \figurenum will be used as the figure identifier. LaTeX's figure counter is not incremented when \figurenum is used. \figurenum must be used inside the figure environment.

\plotone inserts the graphic in the named EPS/PDF file, scaled so that the horizontal dimension fits the width of the body text; the vertical dimension is scaled to maintain the aspect ratio. \plottwo inserts two image files next to each other. Scale factors are determined automatically from information in the EPS/PDF file.

The automatic scaling may be overridden with the command \epsscale{num}, where num is a scaling factor in decimal units, e.g., 0.80.

The plotone and plottwo macros are invocations of the graphicx \includegraphics command. In most instances, using plotone or plottwo should work for placing figures in AASTeX documents. However, if more flexibility is needed, the includegraphics command may be invoked directly. For instance, to rotate an image by 90 degrees, use

\includegraphics[angle=90]{epsfile}

See the graphicx wiki page or package documentation for more information about \includegraphics.

2.14.2 Figure Captions

All electronic art in a manuscript must have a figure caption or legend. Use the \caption command within the figure environment.<\p>

\figcaption[filename]{text\label{key}}

The optional argument, filename, can be used to identify the file for the corresponding figure; text refers to the caption for that figure. The author may provide a \label with a unique keyfor cross-referencing purposes.

When the \figcaption command is used, the figure identification label, e.g., "Figure 1," is generated automatically by the command itself, so there is no need to key this information. There is an upper limit of seven figure captions per page. Footnotes are not supported for figures.

2.14.3 AASTeX 6.0 Figure Features

AASTeX 6.0 introduces a new way to create a figure that consists of > 2 EPS or PDF files arranged in a grid pattern. The new command \gridline allows an author to place as many figure files as needed in a row through multiple \fig, \rightfig and \leftfig calls. The \fig calls an individual EPS or PDF file while \rightfig and \leftfig do the same but right and left justify the named file within the grid row. There is also the \boxedfig call which is the same as \fig but draws a box around the named file.

\fig{filename}{width}{letter or caption}

The first argument is the EPS or PDF file to be displayed. The second argument is the width to scale the file by. Any LaTeX accepted width is valid but author may find it easier to use \textwidth scale the figure by a fraction of the allowed width. For example, 0.33\textwidth will scale the figure to one third the column width. The last argument provides a sub caption beneath the displayed file. Authors should use this to label the displayed file, e.g. "(a)", "(b)", etc.

There is a final file call for \gridline, \rotatefig. Similar to the others, this file call takes an additional argument to specify the degree of rotation. An example would be \rotatefig{90}{}{}{subcaption} to produce a 90 degree rotation.

With multiple \gridline commands an author can construct figures consisting of numerous files and in complex arrangements. The following example will create a 2 X 3 grid that is labeled "(a)" through "(f)" but another example is available in the sample.tex file that is included with the AASTeX 6.0 download package.

\begin{figure}
\gridline{\fig{fig1a.eps}{0.3\textwidth}{(a)}
          \fig{fig1b.eps}{0.3\textwidth}{(b)}
          \fig{fig1c.eps}{0.3\textwidth}{(c)}}
\gridline{\fig{fig1d.eps}{0.3\textwidth}{(d)}
          \fig{fig1e.eps}{0.3\textwidth}{(e)}
          \fig{fig1f.eps}{0.3\textwidth}{(f)}}
\caption{This is the caption for a nice two by three file figure.}
\end{figure}

2.15 Tables

There is support in the AASTeX package for tables via two mechanisms: LaTeX's standard table environment, and the deluxetable environment, which allows for the formatting of lengthy tabular material. Tables may be marked up using either mechanism, although use of deluxetable is preferred. Authors should not use the LaTeX tabbing environment when preparing electronic submissions.

2.15.1 The deluxetable Environment

Authors are encouraged to use the deluxetable environment to format their tables since it automatically handles many formatting tasks, including table numbering and insertion of horizontal rules. It also provides mechanisms for breaking tables and controlling width and vertical spacing that are unavailable in the LaTeX tabular environment. An online tool is available to help create deluxetables.

The deluxetable environment is delimited by LaTeX's familiar \begin and \end constructs. The content consists of preamble commands and table data, the latter delimited by \startdata and \enddata.

\begin{deluxetable}{cols}
preamble commands
\startdata
table data
\enddata
\end{deluxetable}

The argument cols specifies the justification for each column. An alignment token, "l," "c," or "r," is given for each column, indicating flush left, centered, or flush right.

2.15.2 Preamble to the deluxetable

There are several commands in the deluxetable environment that must be given in the preamble if used.

\tabletypesize{font size command}
\rotate
\tablewidth{dimen}
\tablenum{text}
\tablecolumns{num}
\tablecaption{text\label{key}}
\tablehead{text}

If a table is too wide for the printed page, the font size of the table can be cahnged with the \tabletypesize command, which takes as an argument one of the the font size change commands: \small (11pt), \footnotesize (10pt), or \scriptsize (8pt).

To force a table to be set in landscape orientation, use the \rotate command. Note that most DVI previewers will not properly render rotated deluxetable output, so in order to see what the table looks like, it must be converted to EPS or PDF and viewed there.

The width of a deluxetable is defined by \tablewidth. If this command is omitted, the default width is the width of the page. The table can be set to its natural width by specifying a dimension of 0pt. Long tables may have a natural width that is different for each page. The natural width for each page will be printed to the log file during processing. Authors may then use this log information to define a fixed table width in order to give the table a more uniform appearance across pages.

It is possible to override LaTeX's automatic numbering within the deluxetable environment. When \tablenum is specified inside a deluxetable preamble, the text supplied as an argument to \tablenum will be used as the table identifier. LaTeX's equation counter is not incremented when \tablenumis used.

The caption (actually, the title) of the table is specified in \tablecaption. The text of \tablecaption should be brief; explanatory notes should be specified in the end notes to the table (see 2.15.5 below). If the caption does not appear centered above the table after processing, then specify the width of the table explicitly with the \tablewidth command and rerun LaTeX on the file. If an author supplies a \label for cross-referencing purposes, this, too, should be included in the \tablecaption.

Column headings are specified with \tablehead. Within the \tablehead, each column heading should be given in a \colhead, which will ensure that the heading is centered on the natural width of the column. There should be a heading for each column so that there are as many \colhead commands in the \tableheadas there are data columns.

\tablehead{
\colhead{heading} & \colhead{heading}}

If more complicated column headings are required, any valid tabular command that constitutes a proper head line in a LaTeX table may be used. For example, the multicolumn command below would create a table head with text centered over five columns.

\multicolumn{5}{c}{text}

The \tablecolumns{num} command is necessary if an author has multi-line column headings produced by \tablehead or other LaTeX commands and is using either the \cutinhead or \sidehead markup (see below). The num argument should be set to the true number of columns in the table. The command must come before the \startdata command.

2.15.3 Content of the deluxetable

After the table title and column headings have been specified, data rows can be entered. Data rows are delimited with the \startdata and \enddata commands. The end of each row is indicated with the standard LaTeX \\ command. Data cells within a row are separated with & (ampersand) characters.

\startdata
data line
cell&cell&cell
more data lines
\\enddata

Column alignment within the data columns can be adjusted with the TeX \phantom{string} command, where string can be any character, e.g., \phantom{$\arcmin$}. A blank character of width string is then inserted in the table. Four commands have been predefined for this purpose.

\phn phantom numeral 0-9
\phd phantom decimal point
\phs phantom ? sign
\phm{string} generic phantom

Extra vertical space can be inserted between rows with an optional argument to the \\ command.

\\[dimen]

The argument is a dimension and may be specified in any units that are legitimate in LaTeX.

In a table, it may happen that several rows of data are associated with a single object or item. Such logical groupings should not be broken across pages. In these cases, the tablebreak command may be used to force a page break at the desired point.

table row
 \\tablebreak
next table row

This command can be used any time that the default deluxetable page breaks need to be overridden.

To explicitly indicate that a table cell that contain no data, the \nodata command can be used. This is to differentiate such cells from blank cells, which are frequently interpreted as implicitly repeating the entry in the corresponding cell in the row preceding.

Within the deluxetable body, two kinds of special heads are allowed, cutinhead and sidehead. A cut-in head is a piece of text centered across the width of the table. It is spaced above and below from the data rows that precede and follow it and will appear set off by rules in the LaTeX output. Similarly, the command for a side head produces a row spanning the width of the table but with the text left justified.

\cutinhead{text}
\sidehead{text} 

Table footnotes (more properly, table end notes) may also be used in the deluxetable environment. Their use is described in detail in Section 2.15.5.

2.15.4 The table Environment

Authors may also compose tables using the table environment.

\begin{table}
\end{table}

The table environment encloses not only the tabular material but also any title or footnote information associated with the table.

Titles, or captions, for tables are indicated with a caption command

\caption{text\label{key}}

A table label, e.g. "Table 2," is generated automatically by \caption. The author may provide a \label in the caption with a unique keyfor cross-referencing purposes.

The table body should appear within the tabular environment.

\begin{tabular}{cols}
\end{tabular}

The alignment tokens in cols specify the justification for each column. The letters "l," "c," or "r" is given for each column, indicating left, center, or right justification. See the wiki for additional information about using the tabular environment to prepare tables.

Each tabular table must appear within a table environment. There should be only one tabular table per table environment.

Use the tableline command to insert horizontal rules in the tabular environment.

\tableline

The use of vertical rules should be avoided.

As with the deluxetable environment, it is possible to override LaTeX's automatic numbering within the table environment using \tablenum. \tablenum must be used inside the table environment.

2.15.5 Table End Notes

AASTeX supports footnotes and end notes within tables; this support applies to both the deluxetable environment and the standard LaTeX table environment.

Footnotes for tables are usually identified by lowercase letters rather than numbers. Use the tablenotemark and tablenotetext commands to supply table footnotes. As with \altaffilmark and \altaffiltext, a note label, usually a letter, is required.

\tablenotemark{key letter(s)}
\tablenotetext{alpha key}{text}

The key letter of the tablenotemark should be the same as the alpha key for the corresponding text. It is the responsibility of the author to make the correspondence correct.

Sometimes authors tabulate materials that have corresponding references and may want to associate these references with the table. Authors may also wish to append a short paragraph of explanatory notes that pertain to the entire table. These elements should be specified with the commands below.

\tablerefs{reference list}
\tablecomments{text}

The \tablenotetext, \tablecomments, and \tablerefs commands must be specified after the \end{tabular} or \enddata and before the closing \end{table} or \end{deluxetable}.

2.15.6 AASTeX 6.0 Table Features

AASTeX 6.0 introduces five new features to make and display tabular information. The author must have the most current AASTeX classfile in order to use these features. All of these features can be use together in a single table. Examples are available in the AASTeX 6.0 documentation.

2.15.6.1 Hide columns

Entire columns can be "hidden" from display with the use of the new "h" cols column identifier. For example the LaTeX table environment

\begin{tabular}{chc} 
\hline 
one&two&three\\ 
\hline
\hline
a&b&c\\
\hline 
\end{tabular}

or AASTeX deluxetable environment

\begin{deluxetable}{chc}
\tablehead{
\colhead{one} & \nocolhead{two} & \colhead{three} 
}
\startdata
a&b&c\\
\enddata
\end{deluxetable} 

will only display columns "one" and "three". The second column, "two", will not be shown when compiled. In deluxetable the command \nocolhead has to be used instead of \colhead to hid a specific column header. Alternatively, \multicolumn1c can also be used to hid a header in deluxetable. Note that the hidden column still appears latex manuscript. Authors are responsible for removing any unneeded column data or alerting the editorial office about how to treat these columns in during production for the final typeset article.

2.15.6.2 Automatic column math mode

The use of mathmatics and special symbols requires the use of math-mod or in other words prefaced with $s. Using capital letters, e.g. "C", "L", or "R", in the cols column identifier will set that specific column in math mode so that $s are unnecessary. A LaTeX table environment example is shown below.

\begin{tabular}{cCR}
\hline
one&two&\alpha\\
\hline
\hline
a & \sum^{n=0}_{0 \to 1} & 5\pm1\\
\hline
\end{tabular}

An another example but with AASTeX's deluxetable.

\begin{deluxetable}{ClR}
\tablhead{
\colhead{Math} & \dcolhead{\beta} & \colhead{3} \\
\stardata
\frac{a}{b} & 1000 & $\sim a^{\prime}$ \\
\enddata
\end{deluxetable} 

As shown in the second column header the command \dcolhead is used to enable math mode without $s in the header. The last column in the deluxetable shows that embedded $s will not affect capital cols and thus legacy tables can be used without worry.

2.15.6.3 Column decimal alignment

Aligning columns by decimal can be tricky. Prior to AASTeX 6.0 the best way was to use phantom calls such as \phn to manually align each row. For long or wide tables this process can add significant overhead to get the decimals to align properly. AASTeX 6 introduces another new cols column identifier, "T", to automatically align a column by decimal. While the process is similar for both LaTeX tables and AASTeX deluxetables the details are slightly different.

The process works by splitting a decimal column into two separate columns by the decimal and right justifying the first new column and right justifying the second new column. In addition to identifying the decimal column with a "T" (for two columns) in the cols column identifier, the author must include the \decimal in the table. Since "T" columns are actually two column any headers should include an extra "&" or be described with \multicolumn2c. Each decimal column must end with space before "&" and empty decimal columns must be indicated with `.' A LaTeX example is given below.

\begin{tabular}{rTT} 
\hline 
 & & & \multicolumn2c{More} \\
Column & \multicolumn2c{Decimals} & \multicolumn2c{Decimals}\\ 
\hline
\hline
\decimals 
One   & 567.0 & 21345 \\ 
Two   & 2.0   & 62.5  \\ 
Three & 45    & 534.3499 \\ 
Four  & 21.12 & .  \\
\hline 
\end{tabular}

A similar example using AASTeX deluxetable and embedded plus or minus symbols to hightlight the differences is given below.

\begin{deluxetable*}{cT@{+/-}T}
\tablehead{
\colhead{Letter} & \multicolumn2c{Value} & \multicolumn2c{Error} \\
}
\startdata
\decimals
A & 1234     & 100.0     \\
B &  123.4   &  10.1     \\
C &  12.34   &   1.01    \\
D &   1.234  &   0.101   \\
E &    .1234 &   0.01001 \\
\enddata
\end{deluxetable*}

Note that the \decimals call comes after \startdata in deluxetable.

2.15.6.4 Split tables

Wide tables can easily be split horizontally into two or three continuing subtables. An author would invoke splittabular or splitdeluxetable to allow this functionality. Both command take the optional "*" extention to allow the table to span both columns in the twocolumn format. A new "B" cols column identifier is defined to tell LaTeX where to introduce the split. Up to two "B" identifiers can be used. The output is a centered split table with a full horizontal line separating the two or three components. A LaTeX table example below shows how this split a simple table into halves.

\begin{splittabular}{cccBccc}
\hline
one & two & three &four & five & six \\ 
$alpha$ & $\beta$ & $\gamma$ & $\delta$ & $\epsilon$ & $\zeta$ \\
\end{splittabular}

splitdeluxetable works in the same way and both will accept any of these calls in the table cols column identifier: c,l,r, or C,L,R, @{}, p{1in}, |, or ||, m{}, b{}, !{}, or a new column type defined with the \newcolumntype{}{} command. Note that tables should only be split as a the regular tricks of using landscape and smaller fonts do not provide the desired results.

2.15.6.5 Automatic column numbering

The command \tabnumberline can be included to automatically number each column in the header. Each column index number will be surrounded by parentheses. In a LaTeX table the \tabnumberline should be invoked at the location where the author wants the numbers to appear. This should be after the last line of specified table header. In deluxetable this command has to come after \startdata. \tabnumberline will not increment for columns hidden by the "h" command.

2.16 Enhanced Materials

For many years now, the AAS journal of record has been the electronic version. One significant advantage of the move is that electronic delivery offers a substantially wider range of features and functionality that simply is not available in print or even PDF. These enhanced features allow authors to provide the data behind their articles and present that data in new and unique ways. The ultimate goal of all enhanced materials is further the author's vision and provide the reader with data that is discoverable and reusable. The different types of enhanced materials currently supported are provided below.

2.16.1 Machine-readable Tables

Long tables, i.e. more than 250 data lines, in AAS journal articles should be in the machine-readable format for presentation in the electronic edition. Machine-readable tables have two parts: the formatted ASCII data and a metadata header that provides format, units, and short explanations of each column of data. The meta-data header follows the same format and styles as used by CDS in their ViZieR tables. This structure is designed to provide maximum flexibility and ease of use for readers who wish to further manipulate the data. An online tool is available for authors to create their own machine readable tables.

For each machine-readable table, the author must include a short sample version of the full table in his or her LaTeX submission. This sample version will appear in PDF and HTML with the full data only available in the machine-readable format. The sample table should be 5 to 15 lines long and include a table note at the end with text indicating that a machine-readable version will be available in machine-readable format. For instance,

\tablecomments{Table 1 is published in its entirety in the machine-readable format.  
      A portion is shown here for guidance regarding its form and content.}

When a sample table will not fit on a print page, e.g. exceptionally wide tables, there are a number of tricks an author can use to make the table fit. The first is to use a landscaped table which can be accomplished with \rotate in deluxetable. Another option is to use a smaller font size width, see 2.15.2. Some new options available in AASTeX v6.0 includ splitting the table into 2 or 3 parts, see 2.15.6.4, or hiding columns, 2.15.6.1, with the full version as a MRT. Any combination of these options can be used at the same time. In extreme cases or tables where the author wants to provide a more descriptive table, authors may also create a "meta-data" table that only provides the column meta data, e.g. column number, column descriptions, etc. An example can be found here.

Each example table must be cited and numbered as if it were a regular table.

2.16.2 Data behind the Figure (DbF)

Authors may include a portion or all of the data shown in any figure published in the AAS Journals. The data will be posted with the published article in a commonly accepted format, typically machine readable or FITS. Authors must indicate in the figure caption which portion of the displayed data is available as a DbF. An example caption would be "The BVRI photometry shown in panel b of this figure is available as the Data behind the Figure."

2.16.3 Figure Sets

A figure set is the frame work used to contain a large compendia of similar images and graphical material. Examples include identification charts, spectral libraries, model output, etc. The figure set functionality gives the reader the ability to quickly find specific images within the figure set sequence and thus is well suited in cases with many similar images.

Figure sets must be mentioned explicitly by number and appear in correct numerical order in the body of the text. At least one image in a series must be displayed as an example figure for PDF readers. The example caption should indicating that additional images are available in the Figure set. For example, "Plots for all sources are available the Figure Set." the electronic edition of the journal."

AASTeX 6.0 is required to produce a figure set. The commands to construct a figure set are as follows.

\figsetstart
\figsetnum{figurenumber}
\figsettitle{figure set title}
 
\figsetgrpstart
\figsetgrpnum{figurenumber.1}
\figsetgrptitle{image 1 caption}
\figsetplot{figure set file}
\figsetgrpnote{image 1 caption}
\figsetgrpend
 
Repeat the block above for each figure in the set
 
\figsetend

The second command, \figsetnum, is the figure sequence number. The \figsettitle is the title for the entire figure set. The next six commands, between \figsetgrpstart and \figsetgrpend, must be repeated for each image in the figure set sequence. The \figsetgrpnum increments by one each time, e.g. figurenumber.1, figurenumber.2, figurenumber.3, etc. \figsetgrptitle is a title used to uniquely identify the the specific image. It should be relatively short but descriptive. \figsetplot is the call to the eps or pdf file containing the image. If an image consists of multiple eps or pdf files one \figsetplot is required for each file. Lastly, \figsetgrpnote is the figure caption for that specific image. It may be unique or identical to all the others in the figure set but it must be specified in this field.

The example figure or figures should be placed after the figure set mark up and created like a normal figure. An online tool is available to help create the figure set mark up.

2.16.4 Animations

Currently, only animations in the MPEG format, or specifically encoded with the H264 codec, are accepted by the AAS journals. Authors must supply a still frame from the animation in EPS/PDF format included like a regular figure to serve as an example for the reader. This example figure should include text in the caption indicating that an animation is available electronically. For instance, "This figure is also available as an animation." As with figure sets, authors must include enough information in the figure caption for readers of the print edition to determine what the animation illustrates.

2.16.5 Interactive Figures

Interactive figures give the reader the ability to manipulate the information contained in an image which can add clarity or help further the author's narrative. These figures consist of two parts, the figure file in a specific format and a javascript and html frame work that provides the interactive control. An example of an interactive figure is a 3D model. The underlying figure is a X3D file while x3dom.js is the javascript driver that displays it. An author created interface is added via a html wrapper. The first 3D model published by the AAS Journals using this technique was Vogt et al. (2014). Authors should consult the online tutorials for more information on how to construct their own interactive figures.

Since interactive figures are not actionable in LaTeX the only necessary addition to an AASTeX manuscript is to include a non-interactive regular figure to use as an example. The example figure should also indicate to the reader that the enhanced figure is interactive and can be accessed online.

2.17 Miscellaneous

2.17.1 Celestial Objects and Data Sets

Authors who wish to have the most important objects in their manuscript linked to CDS may do so using the

\objectname[catalog ID]{text}

macro, or its alias \object. The text contained in the required argument will be shown in the manuscript and will serve as a link anchor. The catalog ID is an optional argument that will be used as the CDS identifier instead of the primary text. This allows the author more flexibility when constructing the object link. Note that links will only be activated if the name provided in the argument is recognized by a participating data center. It is the author's responsibility to use the correct identifier in either arguement.

Similar markup is available for linking to data sets hosted at participating data centers.

\dataset[catalog ID]{text}

In the manuscript, the text in the required argument will be printed while the the catalog ID value will be passed through to form links to data centers.

2.17.2 Ionic Species and Chemical Bonds

When discussing atomic species, ionization levels can be indicated with the following command.

\ion{element}{level}

The ionization state is specified as the second argument and should be given as a numeral. For example, "Ca III" would be marked up as \ion{Ca}{3}.

For single, double, and triple chemical bonds, use the following macros.

\sbond
\dbond
\tbond

2.17.3 Fractions

AASTeX contains commands that permit authors to specify alternate forms for fractions. LaTeX will set fractions in displayed math as built-up fractions; however, it is sometimes desirable to use case fractions in displayed equations. In such instances, one should use \case rather than \frac. Note, however, that authors using AASTeX should generally find it unnecessary to use any markup other than the standard LaTeX \frac.

Built-up \frac{1}{2} [1/2]
Case \case{1}{2} \case12
Shilled 1/2 1/2

2.17.4 Astronomical Symbols

As mentioned earlier, the AASTeX package contains a collection of assorted macros for symbols and abbreviations specific to an astronomical context. These are commonly useful and also somewhat difficult for authors to produce themselves because fussy kerning is required. See the symbols pages provided with the package distribution. Most of these commands can be used in both running text and math. However, \lesssim and \gtrsim can only be used in math mode.

2.17.5 Hypertext Constructs

The \anchor command is a general-purpose hypertext link tag, associating text in the manuscript with the specified resource (href).

\anchor{href}{text}

href should be specified as a full URI, including the scheme: designator (http:, ftp:, etc.).

The \url command supports the special case where an author wishes to express a URL in the text.

\url{text}

The \email command is used to identify e-mail addresses anywhere in the manuscript. The text of the argument is the e-mail address. Please do not prepend the mailto:part.

\email{address}

This command should be used to indicate authors' e-mail addresses in author lists at the beginning of manuscripts.

2.17.6 Commenting and highlighting revised text with color

The new command \edit1{}, \edit2{} and \edit3{} have been introduced to make it easier for authors to hightlight changes to the manuscript in response to editor and referee comments. The three commands will produce red, blue, and purple , respectively. Authors should use the first command to highlight new text from the first revision, the second command from the second revision and the third command if a third revision is necesary. The goal is to make it obvious what has been changed and at what point during the peer review proccess. For final typesetting the color can be removed simply by adding in the command \turnoffediting in the preamble.

Similarly the \authorcomment1{}, \authorcomment2{}, and \authorcomment3{} commands are now available. These commands will highlight text in red, blue and purple but when the command \turnoffediting is used this text will not be shown at all. Authors can use these commands to mark text that they are not sure should be included in the final manuscript.

2.18 Concluding the File

The last command in the electronic manuscript file should be the

\end{document}

command, which must appear after all the material in the manuscript. This command directs the formatter to finish processing the manuscript.

3 Style Options

The default style option is the onecolumn style. This style will produce a tightly typeset single column at the width of the page.

The twocolumn style produces a tightly typeset double column format similar. It is important to remember that text lines are considerably shorter when two columns are typeset side by side on a page. Long equations, wide tables and figures, and the like, may not typeset in this format without some adjustments. When using this style authors will need to size tables and figures accordingly or use the asterisk option to force these floats to span both columns, see 2.14.1. To invoke this style use

\documentclass[twocolumn]{aastex}

The twocolumn style sets the article's front matter-the title, author, abstract, and keyword material-on a separate page at full text width. The body of the article is set in a two-column page grid, the appendices in a one-column page grid, and the bibliography in a two-column page grid.

The numberedappendix style will number appendices as letters, A, B, C, etc. This is the default behavior. The appendixfloats will use separate numbering for appendix tables and figures. twocolappendix will change from the default of a single column appendix to a two column appendix. All of these styles can be used in conjuction with each other, e.g.

\documentclass[twocolumn,twocolappendix]{aastex}

4 Additional Documentation

The preceding explanation of the markup commands in the AASTeX package has merit for defining syntax, but many authors will prefer to examine the sample manuscripts that are included with the style files. The files of interest are described below.

A comprehensive example employing nearly all of the capabilities of the package (in terms of markup as well as formatting) is in sample.tex. This file is annotated with comments that describe the purpose of most of the markup. sample.tex includes multiple tables and figures. The sample file, along with other documentation, can be obtained in the full distribution download.

5 Acknowledgments

AASTeX was first designed and written by Chris Biemesderfer Robert Hanisch at the Space Telescope Science Institute in 1988. Substantial revisions were made by Lee Brotzman and Pierre Landau when the package was updated to v4.0. AASTeX was rewritten as a LaTeX2eclass by Arthur Ogawa for the v5.0 release. It was updated to v5.2 by SR Nova Private Ltd. Amy Hendrickson (TeXnology Inc.) wrote the v6.0 release which itself was primarily based on the emulateapj classfile created by Maxim Markevitch and Alexey Vikhlinin. Over the years the documentation has benefited from revisions by Jeannette Barnes, Sara Zimmerman, Greg Schwarz, Gus Meunch, Amy Henderickson and Butler Burton.