Has the ancient dream of alchemy finally coming true?
"... the ALICE collaboration reports measurements that quantify the transmutation of lead into gold in CERN's Large Hadron Collider (LHC). ..."
"In a paper published in Physical Review Journals, the ALICE collaboration reports measurements that quantify the transmutation of lead into gold in CERN’s Large Hadron Collider (LHC).
Transforming the base metal lead into the precious metal gold was a dream of medieval alchemists. This long-standing quest, known as chrysopoeia, may have been motivated by the observation that dull grey, relatively abundant lead is of a similar density to gold ...
Though gold has been artificially produced in this way before, the ALICE collaboration has now measured the transmutation of lead into gold by a new mechanism involving near-miss collisions between lead nuclei at the LHC.
Extremely high-energy collisions between lead nuclei at the LHC can create quark–gluon plasma, a hot and dense state of matter that is thought to have filled the universe around a millionth of a second after the Big Bang, giving rise to the matter we now know. ..."
From the abstract:
"The first measurements of proton emission accompanied by neutron emission in the electromagnetic dissociation (EMD) of 208 Pb nuclei in the ALICE experiment at the Large Hadron Collider are presented. The EMD protons and neutrons emitted at very forward rapidities are detected by the proton and neutron zero degree calorimeters of the ALICE experiment. The emission cross sections of zero, one, two, and three protons accompanied by at least one neutron were measured in ultraperipheral 208
Pb −208 Pb collisions at a center-of-mass energy per nucleon pair √𝑠𝑁𝑁=5.02TeV. The 0p and 3p cross sections are described by the RELDIS model within their measurement uncertainties, while the 1p and 2p cross sections are underestimated by the model by 17–25%. According to this model, these 0p, 1p, 2p, and 3p cross sections are associated, respectively, with the production of various isotopes of Pb, Tl, Hg, and Au in the EMD of 208 Pb. The cross sections of the emission of a single proton accompanied by the emission of one, two, or three neutrons in EMD were also measured. The data are significantly overestimated by the RELDIS model, which predicts that the (1p,1n), (1p,2n), and (1p,3n) cross sections are very similar to the cross sections for the production of the thallium isotopes 206,205,204 Tl ."
ALICE detects the conversion of lead into gold at the LHC (original news release) "Near-miss collisions between high-energy lead nuclei at the LHC generate intense electromagnetic fields that can knock out protons and transform lead into fleeting quantities of gold nuclei"
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