Search Guide

Word truncation/stemming

The word truncation is supported via the asterisk (*) wildcard character. The wildcard instructs the search engine to match any number of characters in that place. For example, to find records that contain words muon, muons, muonic etc, type:

Structured metadata search

Searching within various bibliographic fields (such as title, author) is supported via Google's "site:" like syntax. If a search term is preceded by a field name and a colon, then the term is searched for inside this field only. For example, to find documents containing the word ellis within the author index, type:

Regular expressions

The regular expression searching mode is mostly for the power users acquainted with the traditional Unix/POSIX regexp syntax. In the Simple Search interface you can trigger it by using slashes instead of quotes:

Another example could be a search for an author expressed in the database as either Ellis, J or Ellis, John:

The regular expression search enables you to formulate very specific word proximity queries. For example, let us find all titles containing words dense and matter that are separated by at most one word that doesn't contain the letter l:

Note that you can also use character intervals such as [a-k] and occurrence counts such as {3}. For example, let us find all preprints that do not follow the year cataloguing policy, that is YYYY to denote year, optionally followed by ? or by another -YYYY:

To learn more about POSIX regular expressions, please consult the Wikipedia regexp article and the MySQL regexp documentation.

Span queries

The span query is provided via a -> sign. For example, to search for all documents on muon decay published between 1983 and 1992, type:

Combined metadata/fulltext/citation search

All the syntax mentioned above can be combined together in one query. For example, to find documents that have the word ellis inside the author field, that do not contain words like muon, 'muonic' etc in any field, that contain the phrase (or the substring, to be more precise) 'dense quark matter' inside the abstract field, and that were published in year starting by digits '200', type:

Frequently asked questions

How to wisely choose your search terms (speed-wise)

• Whenever possible, prefer word searches instead of phrase searches. Search rather for black hole than for "black hole".
• Avoid common terms such as and, of, or CERN.
• If you are searching for a specific metadata information, such as a report number, select the corresponding index.
• If you are looking for a specific document collection, such as Theses, select the Theses collection first, and start your search from there.

How to search for publications by a given author

You can search for an author in many ways, each having its own advantages and disadvantages.

1. First of all, note that searching for words isn't usually what you would want here. If you choose to search for the words Ellis J within the author index, it means that two queries (for the words Ellis and J) are effected first and a boolean AND is performed next:

   any field title author

   Such a query would match also a document whose first author is Ellis, R and the second author Finch, A J, which is probably not what you wanted. While the search is very fast and you would have found the results for the author you were looking for, such a technique could have returned you many false positives, as the one cited above. Instead of searching for words, a more suitable technique to apply in this case is to search for phrases which will permit you to achieve higher search precisions.

2. The author names are usually stored in a form containing initials only, such as Ellis, J. To get the list of publications of an author whose name is spelt exactly that way, type:

   any field title author

   This way of searching gives you the highest precision and no false positives. (Assuming there are no other authors whose names are spelt Ellis, J, an assumption that is often false^*.) The search is very fast.

3. Sometimes an author's first name may be spelt abbreviated on some documents (such as Ellis, J) and sometimes full on others (such as Ellis, John; possibly also with the middle name: Ellis, John Rolfe). To get the list of publications for all these forms at the same time, you could use a boolean OR query:

   any field title author

   This way of searching still keeps the highest precision and no false positives. (Assuming there are no other authors whose names are spelt Ellis, J or Ellis, John, an assumption that is often false^*.) The search is fast.

4. To match all of the above forms in a single search term, you can try to use a wildcard query:

   any field title author

   It would match all author names that start by the text Ellis, J, i.e. not only the wanted forms Ellis, J and Ellis, John, but also Ellis, Jim, or Ellis, John Rolfe, or Ellis, Jonathan Richard.

   This way of searching returns more results, which may be suitable in case you don't know how the names are spelt in the database. But you also risk the eventuality of getting false positives. The search is relatively fast.

5. Yet another, the most general alternative is to use a partial phrase matching:

   any field title author

   It would find not only all the authors mentioned above, but also the ones whose names contain the expression Ellis, J anywhere inside the name, such as De Lellis, Jim. It thus gives you the largest possible number of hits at the largest risk of false positives. The search is relatively slow.

   (Note though that this way of searching may be very handy in case of compound family names such Pepe-Altarelli, M or 't Hooft, G where a casual user query for Hooft, G would match the wanted author, unlike the methods mentioned above.)

6. Finally, let us note that you can use the regular expression syntax to construct any complex author query. A simple example is to search for an author expressed in the database as either Ellis, J or Ellis, John:

   any field title author

   Please consult regular expression searching tips to find out more about regular expression search possibilities.

^*NOTE: If you produce your own list of publications and you notice that sometimes your first name is spelt abbreviated and sometimes in full, or if you want to identify your publications among several authors with the same abbreviation, please contact the administrators of GSI Repository so that they could work with you on inputting a consistently spelt and properly formatted first name everywhere. Only the consistent database content will ensure a proper author searching behaviour.

How to sort according to a certain pattern

You may select a certain field according to which you wish to sort the search results, for example to sort the results by main title. However, sometimes you may want to sort by a report number and it happens that your documents have several of them. For example, the report numbers hep-ph/0204140, CERN-TH-2002-069 and RM3-TH-02-4 all denote the same document. Now if you sort your search results set containing this document, the system will take into consideration the first report number, that may be any of these three. Sometimes you may want to classify this document under its hep-ph number, sometimes under its CERN number, depending on whether you produce a list of CERN or hep-ph publications. How can you influence the search engine to prefer one report number rather than the other?

In other words, the search engine by default answers a query like "sort by first author" or "sort by first report number", but sometimes you may want to ask the search engine to "sort by first report number that starts by the text CERN-". The latter possibility is available via a "silent" sort parameter called sp (for "sort pattern") that sorts preferentially according to the given textual pattern if it can be found. The parameter is "silent" in a way that it is not present in the search interface: you have to add it manually to your search URL. For example, to get all CERN-TH publications of the year 2001 sorted by their CERN-TH numbers, you would search for CERN-TH-2001* within reportnumber index, and on the search results page, being satisfied with the results, you would add &sp=CERN-TH to the URL to sort the results preferentially by CERN-TH report numbers, to get a nicely sorted list of all CERN-TH 2001 publications.

How to search in fulltext files

If a metadata record contains some associated fulltext files, GSI Repository tries to extract the textual information from the files and index it into a separate fulltext index. To search for all records that contain the term e- in their fulltext files, type: