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Paparazzi or preprints?

The PAMELA experiment is a satellite mission that is looking at cosmic rays in an attempt to understand, among other things, the dark matter composition of the universe. Apparently the experiment has recently observed an excess of positron events that might hint at dark matter annihilations in the nearby galaxy. The findings have yet to be published, and since these measurements are difficult, there could be any number of possible explanations. The experimenters themselves are being careful not to read too much into the preliminary results, however the community as a whole is quite excited to see them. As is often the case in this field, the PAMELA folks are giving talks at summer conferences and showing brief glimpses of slides containing the new results.

The difference in this case is that the relevant publication has been submitted to the journal Nature, which has, according to some, embargoed the results. Embargoes, wherein a publisher requires authors of a paper not to share the results (except under restricted circumstances) before they appear in the journal, are relatively common in some fields, as journals often want to break the news of a newsworthy result. However, in high-energy physics, they are not as common. In HEP, it is generally the case that authors will submit results to the eprint arXiv before the relevant article appears in the journal. This practice allows results-hungry physicists to get a preliminary look at the paper as it is still going through the review process, and the traditional journals of the field all allow this valuable preprint communication to occur. Nature and other journals that are not frequent destinations for HEP papers, however, don't always go along with the traditional HEP model of publication, and this clash of cultures can have interesting effects.

In this case, theorists attending a conference where the PAMELA results were flashed briefly were ready to take a closer look. They simply took a digital photo of the results, and then wrote papers comparing these preliminary results to existing models of dark matter, correctly attributing the source of the data and noting it as preliminary. Nature appears to be somewhat upset, referring to the physicists as "paparazzi". The PAMELA folks themselves seem a bit mixed, as the spokesperson at the conference appears to have given permission for the photos to be used this way, while the Principal Investigator seems to feel differently.

On the blogs above the discussion rages on, and the conversation is probably a useful one for the community to have, as there are two separate but important issues to consider:

1) If it is true that the results would have been made available had Nature not embargoed them, one can ask: Should HEP authors submit to journals that hamper traditional (preprint) modes of communication? If they do, how should the HEP preprint culture cope with these exceptions?

2) If, on the other hand, the results were not to have been made public, regardless of the journal's policies, one can ask: Should experiments stop showing "sneak-peeks" at conferences, in an era when anything said or shown in a public forum can show up on a blog or in a paper a few hours later? Should conference audiences be expected to allow presenters to discuss preliminary things without looking at them "too hard"?