Heavyweight Aluminium and Magnesium isotopes discovered may explain neutron star X ray oscillations

The atom, is the smallest particle of matter.

It consists of a dense nucleus which contains
Protons - positively charged protons
Neutrons - neutral

Surrounded by a cloud of electrons which are positively charged.

An element’s atomic number defines the number of protons - atoms have an equal number of protons and neutrons, isotopes may exist with an identical number of protons but a different number of neutrons, giving the atom a different mass number. An atom may have multiple unique isotopes each with distinctive properties - viz. Uranium..

How many neutrons can an atomic nucleus hold? Possibly a lot more than current scientific models predict. That's the conclusion a team of physicists reached after creating three ultra-heavy isotopes of magnesium and aluminum.(Nature Oct. 25 2007)

Theoretically Aluminum-42, which is composed of 13 protons and 29 neutrons, shouldn’t exist. The fact that Aluminum-42 does exist suggests the possibility of more neutron-rich isotopes than scientists previously considered likely or possible.

Now Thomas Baumann and his colleagues at Michigan State University’s National Superconducting Cyclotron Laboratory (NSCL) have created and detected three rare isotopes

Aluminum-42
Aluminum-43
Magnesium-40

Thomas Baumann and his colleagues shot nuclei of calcium-48—the heaviest naturally occurring calcium isotope—at a tungsten foil at about half the speed of light. Atomic collisions created all sorts of debris, including fragments from both calcium and tungsten nuclei, out of which new atomic nuclei occasionally formed.

Then they used a dual filtering process that detected and measured isotopes so rare that they represent only one in every billion million particles that passed by the detectors.This was one of the first uses of two-stage separation in the world

Hendrik Schatz, an NSCL physicist who was not involved in the experiment, points out that this result complicates physicists’ efforts to understand how stars and supernova explosions forge neutron-rich isotopes as intermediate steps toward creating elements heavier than iron.

These new results are more directly related to another astrophysical scenario. When matter falls onto a neutron star and starts sinking into its crust, pressures 10 trillion times as high as those at the sun's center force electrons and protons to merge, forming neutrons. The transient formation of these heavy isotopes could help explain certain anomalous flashes of X-rays that astronomers have observed coming from neutron stars, (first discovered by discovered by the Rossi X-ray Timing Explorer satellite in 1996) Schatz speculates.

The research also suggests that other elements, higher in the periodic table, might also be able to accommodate more neutrons than expected.