The quest of discovering the limit of nuclear stability continues to brew among the heavy element community and thus in the process contributed greatly in the discovery of new transuranic elements.

Just recently, Scientists from the Chemistry, Materials and Life Sciences Directorate at Lawrence Livermore National Laboratory, in collaboration with researchers from Dubna, the Joint Institute for Nuclear Research (JINR) in Russia , have discovered the newest superheavy element, element 118.

In experiments conducted at the JINR U400 cyclotron between February and June 2005, the researchers observed atomic decay patterns, or chains, that establish the existence of element 118. In these decay chains, previously observed element 116 is produced via the alpha decay of element 118.

The results are published in the October 2006 edition of the journal Physical Review C.

The experiment produced three atoms of element 118 when calcium ions bombarded a californium target. The team then observed the alpha decay from element 118 to element 116 and then to element 114. The Livermore-Dubna team had created the same isotope of element 116 in earlier experiments.

This discovery brings the total to five new elements for the Livermore-Dubna collaboration (113, 114, 115, 116 and 118).

“The decay properties of all the isotopes that we have made so far paint the picture of a large, sort of flat ‘Island of Stability’ and indicate that we may have luck if we try to go even heavier,” said Ken Moody, Livermore’s team leader.

The “Island of Stability” is a term from nuclear physics that describes the possibility of elements which have particularly stable “magic numbers” of protons and neutrons. This would allow certain isotopes of some transuranic elements (elements with atomic numbers greater than 92) to be far more stable than others, and thus decay much more slowly.

Element 118 is expected to be a noble gas that lies right below radon on the periodic table of elements.

“The world is made up of about 90 elements,” Moody said. “Anything more you can learn about the periodic table is exciting. It can tell us why the world is here and what it is made of.”

Members of the Livermore team include: Moody, Dawn Shaughnessy, Mark Stoyer, Nancy Stoyer, Philip Wilk, Jacqueline Kenneally, Jerry Landrum, John Wild, Ron Lougheed and former LLNL employee Joshua Patin.

“This is quite a breakthrough for science,” said Chemistry, Materials and Life Sciences Associate Director Tomas Diaz de la Rubia. “We’ve discovered a new element that provides insight into the makeup of the universe. For our scientists to find another piece of the puzzle is a testament to the strength and value of the science and technology at this Laboratory.”

Livermore has had a long-standing heavy element group since the inception of the Laboratory in 1952. The group has been successful in the discovery of several new elements over the years because it has access to unique materials to perform the experiments. In 1999 and 2001, the Laboratory announced the discovery of elements 114 and 116, respectively. In 2004, the Livermore-Dubna team observed the existence of elements 113 and 115.

As for the future, the LLNL-Dubna team will continue to map the region near the “Island of Stability.” In 2007, the team plans to look for element 120 by bombarding a plutonium target with iron isotopes and in this process would led them a step closer to the expected nuclear stability limit.

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Supernova 2005ap, the most powerful object ever discovered peaked at more than 100 billion times the brightness of the sun.

Astronomer Robert Quimby discovered the current record holder, supernova 2006gy, last year as part of his Texas Supernova Search project. Now he announces that a supernova he discovered earlier in the project “supernova 2005ap” is actually twice as luminous. Using follow-up studies to pinpoint its distance, Quimby deduced that this supernova is a Type II because it contains hydrogen. Most Type II supernovae are thought to result when the cores of massive stars, those seven to eight times or more heavy than the Sun, collapse under their own weight and trigger an explosion. This particular Type II is 300 times brighter than average, Quimby said, and lies in a dwarf galaxy in the constellation Coma Berenices, well behind the famous Coma cluster of galaxies.

“It’s clearly not the same as 2006gy,” Quimby’s colleague and supernova expert J. Craig Wheeler of The University of Texas at Austin said. “It’s a puzzle.”

Quimby completed his Ph.D. under Wheeler’s supervision at Texas in May, and has just begun a post-doctoral appointment at Caltech. His Texas Supernova Search uses the 18-inch ROTSE-IIIb robotic telescope on McDonald Observatory’s Mount Fowlkes, a tiny neighbor to the giant 10-meter-class Hobby-Eberly Telescope (HET).

Quimby studied 2005ap with HET just a few days after its discovery. The results were intriguing, Quimby said. The supernova’s spectrum hinted at the presence of a highly shifted absorption line of oxygen III (an oxygen atom that has lost two of its electrons). Quimby knew that if the feature was oxygen III, then 2005ap was “possibly very far away and thus very luminous.”

Follow-up observations with the Keck Telescope in Hawaii by Quimby’s colleague Greg Aldering of Lawrence Berkeley National Lab not only confirmed Quimby’s HET detection of oxygen III, but added another, equally shifted element to the spectrum: magnesium.

Together, the studies confirmed 2005ap’s distance of 4.7 billion light-years. (In astronomical terms, this equates to a redshift of z = 0.2832.)

It was this distance measurement, combined with measurements of the supernova’s apparent brightness that allowed the calculation of its intrinsic brightness, or “luminosity,” and uncovered 2005ap as the most powerful supernova yet.

“Before 2006gy, I thought this should not be plausible,” Quimby said. “There I was finding my first supernovae — I was just happy to get anything. It turned out to be the most luminous supernova ever found.”

How is that Quimby has found the brightest supernova yet, twice in a row? “I’ve worked too damn hard for this to be luck,” he said.

Quimby explained, “I’m searching a huge volume of space, comparable to all previous nearby supernova surveys combined.” Also, in fact, 2006gy was found in the core of a galaxy, and that galaxy has a weakly active central black hole, Wheeler said.

“There’s no question that [his results] have gotten everybody’s attention,” Wheeler said. The University of Michigan-run ROTSE collaboration, whose main mission is the search for gamma-ray bursts, has decided to expand the supernova search to its entire network. Its robotic telescopes in Australia, Turkey, and Namibia will soon join the unit at McDonald Observatory in this search. The Sloan Digital Sky Survey Supernova Search, for which the HET provides confirming spectra, is also reconsidering its search filters in response to these discoveries, Wheeler said.

The result has been accepted for publication in the October 20 edition of The Astrophysical Journal Letters.

The Hobby-Eberly Telescope is a joint project of The University of Texas at Austin, The Pennsylvania State University, Stanford University, Ludwig-Maximilians-Universität München and Georg-August-Universität Göttingen.

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The “Principle of Limited Sloppiness” is the phrase coined by Science to describe fortuitous or accidental discoveries such as the following stories of some of the most important discoveries which were brought upon by chance.

In 1791 Luigi Galvani was an anatomist at the University of Bologna. Galvani was investigating the nerves in frog legs, and had threaded some legs on copper wire hanging from a balcony in such a way that a puff of wind caused the legs to touch the iron railing. A spark snapped and the legs jerked violently (even today, we speak of being “galvanized” into action). In one unintended step, Galvani had observed a closed electrical circuit, and related electricity to nerve impulses.

In 1879, Louis Pasteur inoculated some chickens with cholera bacteria. It was supposed to kill them, but Pasteur or one of his assistants had accidentally used a culture from an old jar and the chickens merely got sick and recovered. Later, Pasteur inoculated them again with a fresh culture that he knew to be virulent, and the chickens didn’t even get sick. Chance had led him to discover the principle of vaccination for disease prevention.

Wilhelm Roentgen was experimenting with electrical discharges one evening at the University of Wurzburg in 1895. There was a screen coated with a barium compound lying to one side, and Roentgen noticed that it would fluoresce when an electrical discharge would occur in the tube he was watching. On reaching for the screen, Roentgen got his hand between the discharge tube and the screen and saw the bones of his own hand through the shadow of his skin. In 1901, Roentgen received the Nobel prize for his accidental discovery of X-rays.

Alexander Fleming was a young bacteriologist at St. Mary’s Hospital in London in 1928. One day in his cluttered laboratory, he noticed that a culture dish of bacteria had been invaded by a mold whose spore must have drifted in through an open window. Under the microscope, he saw that, all around the mold, the individual bacteria that he had been growing had burst. He saved the mold, and from it produced the first penicillin.

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