Capturing Femtosecond Snapshots of Molecular Processes 22
umarkalim writes "Staff Scientist Apurva Mehta says, 'For 40 years at Stanford Synchrotron Radiation Lightsource, we have been taking very high-resolution photographs-photographs of atoms in molecules and crystals and of electronic structures. But now we want to make movies.' He and his colleagues are developing a new 'pump-probe' facility that promises to expand SSRL's capabilities and complement those of SLAC's X-ray laser, the Linac Coherent Light Source."
Differences from Zewail's Lab? (Score:4, Informative)
This looks like it may simply be an implementation of the process described [nobelprize.org] by Ahmed Zewail in the 90's, which also operates on femtosecond time scales. Perhaps this "pump-probe" deal is what makes this approach novel?
Re: (Score:2)
This one's x-ray instead of optical.
Re:Differences from Zewail's Lab? (Score:5, Informative)
Still photos, but of shorter wavelength. Shorter wavelength == finer resolution.
Imagine you are blindfolded and are trying to determine the shape of some three dimensional object that you can't touch. You'd get a finer picture of the thing if you probed it with the tip of a pencil than if you felt it through a boxing glove.
This is hardly new (Score:1)
Time resolved X-ray crystallography has been done on biological samples for some time, using synchrotron radiation and a laser-excitable sample. This is done routinely at Argonne's Advanced Photon Source and at ESRF, in Grenoble. For a sample publication, from 1998, see http://www.ncbi.nlm.nih.gov/pubmed/9506946.
Re: (Score:2)
Hardly news? This experiment (mostly the LCLS, but hopefully the SSRL soon) is working on a picosecond (SSRL) and femtosecond (LCLS) timescale. The paper to which you refer is looking at nanosecond timescale information. Three to six orders of magnitude in time resolution. This means they can begin to look at motions of atoms and small chemical groups rather than only seeing motions of large (i.e. slow-moving) molecular subunits. Lots of interesting stuff happens on a ns timescale. A lot more stuff ha
pump probe technology (Score:1, Funny)
2. ???
3. profit!
Can we get a sound track too? (Score:2)
Boom chicka wow wow...
Re: (Score:2)
Is this an automated account or an actual person? Either way, promoting nutrition and exercise to geeks? Methinks your efforts are wasted - the ones (few?) that do exercise and eat healthily probably already know more about it than the average personal trainer/nutritionist, and the rest aren't going to care. Even then, the clickthrough rate from slashdot has got to be 0?