No WIMPs yet (and no HE neutrinos either)

There were big expectations for Xenon 100, a leading experiment in the race for the direct detection of Dark Matter. But the results announced today are somewhat disappointing, since the collaboration announced the detection of 3 events, while the expected background is of 1.8±0.6 events. (see also the discussion at Resonaances).
Should we panic? Not yet, in my opinion. As argued elsewhere, the best we can do is to stick to our plans, and see what ton-scale experiments (and the LHC) will tell us, before drawing our conclusions about WIMP Dark Matter.

New results of the neutrino telescope IceCube have also been published recently (see here and here). As the collaboration acknowledges: “The results from all searches are compatible with a fluctuation of the background”, which means that no point sources have been detected.

Space traffic jam: AMS-02 launch postponed to April 29

The launch date of the Alpha Magnetic Spectrometer AMS-02 (“-02” because it is the successor of first AMS experiment, flown into space in June 1998) has been postponed to April 29 (above, an image of AMS-02 in the bay of the Shuttle Endeavor). 
The delay is not due to the severe weather conditions of the past week, that produced only “very minor” damage, but to a conflict with the docking operations of the Progress M-10M cargo ship, a russian vehicle that will deliver up to 2.5 t of propellant, scientific equipment, food, air, water, etc. to the International Space Station (ISS), scheduled for launch on April 27 from the Baikonur Space Center in Kazakhstan. 
Apparently, the problem comes from the time-sensitive nature of the Progress cargo, a biological experiment which needs to be placed into one of the ISS’ freezers within days of launch..
Although postponing the launch by 10 days is not dramatic per se, the launch date is getting uncomfortably close to the end of the launch window (see here a description of how it is determined).

More surprises from PAMELA

The PAMELA satellite has been launched in 2006 and since then it has held many surprises. Back in 2008, the PAMELA collaboration found an anomalous cosmic positron abundance, which prompted the publication of hundreds of papers (690 citations to the original paper as of March 8, 2011). 
Last week, the collaboration has published on ‘Science Express‘ the measurement of proton and Helium spectra in the rigidity range 1 GV – 1.2 TV (see figure above). The shape of these spectra deviate significantly from the simple power-law behavior predicted by the current paradigm (see e.g. this review paper), which posits that cosmic rays in this energy range are accelerated in supernova remnants. 

Interestingly, the deviations from the predictions are different from protons and He nuclei, a feature that is difficult to accomodate even in the most sophisticated models of acceleration. 
In short, this means that we are probably seeing the effect of new sources of cosmic rays (in the paper the authors cite e.g. this study of a multi-component population of cosmic rays).

Convincing proof of extraterrestrial life?

On March 2, the Journal of Cosmology has sent an invitation to send a 1000 words commentary on a paper of R. Hoover  (go there only if you are interested, as they’ll try to redirect you to the Amazon.com page of a book edited by Hoover. Very, very bad!), claiming the discovery of indigeneous microfossils in the interior of some meteorites, similar to fossilized Earth bacteria. The key-word in the sentence above is “indigenous”, since it implies that these microfossils represent the remains of bacteria which lived outside the Earth.
Now, I found it rather bizarre that a journal requests a 1000 words commentary to anyone in the scientific community is willing to say something. They even specify: 

Commentaries may focus entirely on Dr. Hoover’s paper, or you may speculate about the implications, e.g, the evolution of life on other planets, the origin of life on Earth, our genetic ancestry, “are we alone?” etc.

Oh, well. And to be honest, given the comments that actually appeared on the webpage of the Journal, I’d be surprised if they were actually peer-reviewed at all (as claimed by the editors).

Despite the premises, I tried to develop an informed opinion, to answer the questions of friends and family who read about the news everywhere on the web. After reading about it here, here, here and here, I am tempted to say that the claim is far from robust, and, to say the least, it should be taken with a huge grain of salt.