## 1. Latex F.A.Q.

### How do I include the bibliography in my document?

1. Include the references directly in the latex file:

\begin{thebibliography}{99} \bibitem{Bib1} M\ezard M and Parisi G, \emph{Thermodynamics of glasses: a first principles computation}, 1999 \emph{Phys. Rev. Lett.} {\bf 82} 747. ... \end{thebibliography}

2. Use Bibtex:

For example:

\bibliographystyle{plain} \bibliography{mydocument}

in this case you must import the bbl file correctly in the latex file and include the bbl file in your submitted archive.
It is useful if you also include the .bib file in the archive to be submitted.

Further information on Bibtex can be found here:
- a list of the entry types that can be used in the bib file: http://en.wikibooks.org/wiki/LaTeX/Bibliography_Management#Standard_templates
- a Bibtex tutorial with a list of the bibliography style that can be specified in the latex document: http://amath.colorado.edu/documentation/LTeX/reference/faq/bibstyles.html

3. Do not include the bibliography using the \include or \input command.
4. If after submission the bibliography is missing please write to the editorial office at jcap-eo@jcap.sissa.it.

### How do I include line numbers in my document?

You can use the lineno package which provides line-numbering and various options for customization as shown in the following example.

 \usepackage{lineno} \begin{document} \setpagewiselinenumbers \linenumbers ... 

### How do I include .ps or .eps figures in my Latex document?

Use graphicx: include the graphicx package at the start of the latex file, immediately after the documentclass statement as shown in the following example:

 \documentclass[11pt,a4paper]{article} \usepackage{graphicx} ... 

then include the figure in the body of your article with the \includegraphics command. Width, height and other options (scale, angle, ... ) can be also be specified.

 \includegraphics[width=60mm,height=70mm]{myfig.eps} 

NB: Figure file names are case sensitive and must not contain spaces.

### How do I include .jpg, .pdf or .png figures in my Latex document?

You can use graphicx (include the graphicx package at the start of the latex file) but you must also add \pdfoutput=1 immediately after the \documentclass command as shown in the following example:

 \documentclass[11pt,a4paper]{article} \pdfoutput=1 \usepackage{graphicx} ... 

Important note: if you use a package such as jcappub.sty that already includes the graphicx package, it is not necessary to explicitly include graphicx in your .tex file. The following example is acceptable:

 \documentclass[11pt,a4paper]{article} \pdfoutput=1 \usepackage{jcappub} ... 

NB: Figure file names are case sensitive and must not contain spaces.

### Are there problems with high resolution images?

If the figure file size is very large, the generation of the pdf will take longer than normal which may result in a system timeout and generate an empty .pdf file (see "A blank pdf file has been generated").

The use of very high resolution figures may affect the size of the final .pdf file, increase the download time of your article and increase the time needed to visualize the page containing a very high resolution figure.

Figures can be used to improve your article, and their readability is very important. Readability does not imply high resolution, so a tradeoff should be made in order not to create an unnecessarily large .pdf file.

### Does your system have any particular Latex requirements?

Yes

1. The \documentclass command and all its options must be typed on a single line.

2. If you use pdfex you must add \pdfoutput=1 immediately after the \documentclass command.

3. File names must not contain spaces and are case sensitive

4. If you use Bibtex the bib file must be included in the submitted archive

## 2. Archive preparation F.A.Q.

### When do I need to create an archive file for submission? (.tar.gz or .zip)

If your submission contains more than 1 file, you need to submit a tar.gz or zip archive containing all the necessary files for a successful compilation (see "What files do I need in my archive")

### How do I create an archive file for submission? (.tar.gz or .zip)

First locate the folder ('mypaper' in our example) that contains all the files that need to be compressed.

Linux/MAC tar.gz:
- open a terminal window, and navigate to the 'mypaper' directory (es. $cd mypaper/) - the main tex file must be in the 'mypaper' directory (and not in a subdirectory of it) - type $ tar -cvzf article.tar.gz *
- this creates an archive called "article.tar.gz" containing all files and folders in the 'mypaper' directory

Linux/MAC zip:
- open a terminal window, and navigate to the 'mypaper' directory (es. $cd mypaper/) - the main tex file must be in the 'mypaper' directory (and not in a subdirectory of it) - type $ zip article.zip *
- this creates an archive called "article.zip" containing all files and folders in the 'mypaper' directory

Windows/MAC zip:
- there are various programs (winzip, stuffit) that produce zip files on windows/Mac. The important point to remember is that the main tex file must be in the 'mypaper' directory (and not in a subdirectory of it).

### What files do I need in my archive?

Master file:
TeX/Latex submission - it is the .tex file to compile.
note: the master file must be placed in the root directory of the archive.

If two or more source files have the same extension (i.e. "main.tex" and "definition.tex"), when submitting your article you must specify the master file name in the appropriate field (Master file name:), otherwise the submission will fail.

All figure files:
The files of all the figures used in your article must be included.

Other files:
- Bibliography files (e.g. .bbl, .bst, .bib. See "How do I include the bibliography in my document")
- any non-standard or customized packages used.
- some files related to the used packages (e.g. always include the .pk, .tfm and .t1, .t2, ..., files if you are using the feynmf package)
- the definition file(s) and many other.

Do not include: the pdf of your article, unused figures or any other unnecessary files (such as referee report ecc). Supplementary material can be uploaded separately after the archive upload (see "Supplementary material attached" in the JCAP author pages),

Important notes on file names:
File names are case sensitive and must not contain spaces.

### Is there a size limitation for my archive?

Yes. The maximum archive file size that is accepted for upload is 10MB

## 3. Submission FAQ

### How should I prepare my submission if it includes more than one file?

If your TeX/LaTeX submission includes multiple files, you should create an archive that includes the tex master file, the files for the figures, if any, and the .bbl file if you have used BibTeX. More than one TeX/LaTeX file can be included in your archive but, in this case, you must indicate the name of the master file in the submission form during the submission process. Please make sure the master file is not saved in a subdirectory of the archive and that the all figures are included in the TeX/LaTeX file.

Please note that large tables, additional figures, computer programs, output files or video clips can be submitted as additional material, by clicking on the button "upload file" after the successful submission of the article (see "Supplementary material attached" in the JCAP author pages).

See also the section "What files do I need in my archive" and "How do I create an archive file".

### Can a file name contain spaces?

No. Please enusure that all file names do not contain spaces

Remember that if you change the name of the files included/referred in your Latex article (figures' name, bibliography file,...), then the main .tex file has to be updated accordingly.

### Are file names case sensitive?

Yes. If File1.eps is refered to in the Latex article, the system expects to find File1.eps and not file1.eps

Remember that if you change the name of the files included/referred in your Latex article (figures' name, bibliography file,...), then the main .tex file has to be updated accordingly.

### What type of files can I submit?

.tex
.tar.gz
.zip

Other file types are not accepted.

### Submission via web upload: what information is required?

The figures below provide an example of correctly compiled submission form.

The field "arXiv id" in the first window is mandatory and your submission will fail if you do not provide it.

Then after selecting the appropriate keywords to characterise your work, a third window will show the metadata of your paper as extracted from arXiv, and will allow you to choose the file to be uploaded.

If more than one .tex file is included in your archive, please specify the master file name; the .tex extension must be included (e.g. myfile.tex).

If it is not provided you will recieve the following error:
"The system is unable to find the master file"
and you should repeat the submission process specifying the master file name.

### Submission from the arXiv: what information is required?

The figures below provide an example of correctly compiled forms.

The field "arXiv id" in the first window is mandatory and your submission will fail if you do not provide it.

Then after selecting the appropriate keywords to characterise your work, a third window will show the metadata of your paper as extracted from arXiv.

If more than one .tex file is included in your archive, please specify the master file name; the .tex extension must be included (e.g. myfile.tex).

If it is not provided you will recieve the following error:
"The system is unable to find the master file"
and you should repeat the submission process specifying the master file name.

### What checks are performed during submission?

There are 6 checks for a successful submission:

Step 0.
The extension of the uploaded file is checked. The only extensions accepted are: .tex, .zip and .tar.gz.
Steps 1 and 2.
When a compressed archive file is submitted, the system checks that it is not corrupted and can be correctly uncompressed.
If the system can not uncompress and extract the files from your archive, it will trigger a submission error.
You can follow the instruction on "How do I create an archive file" to avoid submission problems.
Step 3.
File format checked. The uploaded file format is checked to see that it corresponds to the format selected by you
Steps 4 and 5.
The system searches for the master file and returns and error if it can not find it.
You can follow the instruction on "How do I create an archive file" to avoid submission problems.
Step 5.
The system compiles the Latex file (compilation errors may occur) to create the pdf of the article. If the generation of the pdf takes too long (for example because of large figures included), a timeout may occur.

If you have a submission error in one of these steps, consult the section "The submission cannot be accepted by the system".

Remember that the submission can be completed only if your file compiles successfully on the JCAP server. Therefore, please check the pdf generated by the system.

### What does the "The system is unable to find the master file" error mean?

It means that the system can not locate the master file inside the submission archive, and it is probably placed inside a sub-directory of the archive.

The master file (.tex) must be placed in the root directory of the archive.

## 4. Submission errors

### Invalid parameter

You will receive an error message if you have entered an invalid arXiv id, or an invalid parameter in any of the mandatory fields (i.e. "authors", "title", "abstract", etc.)

When submitting your own file an error message is displayed in one of the following cases:

• The "File To process" field contains an invalid file name;
• The file you are trying to upload is not supported (e.g empty files, unsupported formats, etc.).

### An error has occurred while connecting to the archive

Please enter a valid arXiv article id. If the problem persists, please try again later as a connection problem may have occurred.

There can be several reasons for this, including:
• wrong arXiv id: please verify that the arXiv id is a valid one. Both old and new arXiv article identifiers are supported (e.g. 1234.5678 or hep-th/12345).
• arxiv.org is temporarily unavailable: please try submitting later.
• the submission was performed too soon after uploading the article to arXiv. The submission therefore fails because preprints uploaded to arXiv are not available for approximately 24 hours.

Sorry: there has been a connection error with http://xxx.arxiv.org/ftp/

Either there is a network error or the site http://arxiv.org is not responding.

Sorry: cannot find archive/0404566 at http://xxx.arxiv.org/ftp/"

The system was unable to download the file because it could not be found.

There can be several reasons for this, including:

• The contribution uploaded to arXiv is not a .tex file (it may be a .pdf file or an MS Word document). For the time being the system only accepts submissions from arXiv of .tex files.
• The submisison was performed too soon after uploading the article to the archive. The submission therefore fails because preprints uploaded to arXiv are not available for approximately 24 hours.

### The submission "cannot be accepted by the system"

An error has occurred in one of the 6 steps of the upload process :

### Submission failure: submitted file size is greater than limit

The size of the submitted file exceeds the system limit of 10 MB.

Try to reduce the size of the archive file you are submitting see "What files do I need in my archive?" and repeat the submission including only the files that are strictly necessary your archive.

If the submitted archive or file includes a video or other files that can be viewed separately from the contribution, these can be submitted as separate attachments after contribution has been uploaded successfully.

### Submission failure: empty file received

The submitted file is empty. Please check the submitted archive file or try to recreate the archive file
(see "How do I create an archive file").

## 5. System error after clicking "upload file"

### A system error has occured

The main cause of this type of error is that the bibliography is not included correctly in your Latex article.

## 6. Successful submission but there are some problems

### "There is no format available yet" is displayed in the preprint page

An error occurred whilst generating the pdf file. Our technical staff have been informed automatically of the problem and it will be resolved as soon as possible. The author and the editor will be informed by the Editorial Office as soon as the files are available.

Your submission was performed long ago, the files have been archived and thus are no longer readily available on the page. Should you need to access them, please write to the Editorial Office.

### A blank .pdf file has been generated

An error occured during the pdf generation.

Please inform the Editorial Office of the problem.

This problem is mainly caused by a timeout due to large images in the article. If this is the case, please use smaller sized images in future submissions.

### The .pdf file is not complete

This is usually due to a problem with a figure file (e.g. the figure is corrupted or has a technical problem).

Please inform the Editorial Office of the problem.

If this is the case, in future submissions, please check integrity of your figures before submission.

### Figures are missing from the .pdf file

Please inform the Editorial Office of the problem.

In a Latex submission, it could be that the figures are corrupted or need additional files/package not present in the archive. (see "What files do I need in my archive")

### Figures are misplaced in the .pdf file

All figures should be cited in the text, therefore the misplacement should not affect the content of the article.

### The references are missing from my .pdf file

For future submission please check that:

## 7. Common errors

The most common errors relate to figures, bibliography and file names:

• the masterfile is not placed inside the root directory of the archive or was not specified in the submission form
• your Latex article uses .png, .jpg or .pdf figures and \pdfoutput=1 is missing in the line following the \documentclass command
• a figure is missing in the archive.
• a .tex file is missing in the archive.
• there are spaces in the file names

### The masterfile is not placed in the root directory of the archive

The master file (.tex) must be placed in the root directory of the archive.

### Your Latex article includes .png .jpg or .pdf figures

If your Latex article uses .png, .jpg or .pdf figures, then a Pdflatex compilation is required.

You must add \pdfoutput=1 on a separate line immediately after the \documentclass command as shown in the following example:

 \documentclass[11pt,a4paper]{article} \pdfoutput=1 \usepackage{graphicx} ... 

Remember that ps and eps images are not allowed in pdflatex.

### Latex compilation errors regarding figures

Latex compilation errors regarding figures are very frequent. The most common reasons are:

• The figures included in your article have extension .png .jpg or .pdf and \pdfoutput=1 is missing (see "Pdflatex")

• The file names contain spaces.
(see "Can a file name contain spaces?")

• A figure is missing in the submitted archive.
(see "How do I create an archive file")

• The figure file name does not match the one in the latex file.
(Remember filenames are case sensitive and no spaces are allowed).

### Latex compilation errors regarding the bibliography

If the system can not locate the bibliography file, it will generate an error. The most common reasons are:

### Latex compilation errors regarding file names

The most common errors are:

• there are spaces in the filenames.
Please see "Can a file name contain spaces?"

• the actual file name does not correspond to the one specified in the latex document.
(Remember filenames are case sensitive and no spaces are allowed).

### Latex compilation errors regarding the command \documentclass

The \documentclass command and all its options must be typed on one line.

The following will produce an error:

\documentclass[a4paper, 11pt, twocolumn] {article}

The following is correct:

\documentclass[a4paper, 11pt, twocolumn] {article}`