The nanoplasma model [15,30,31] provides an explanation for the much higher ion energies seen from large clusters compared to molecules and small clusters in terms of highly efficient collisional heating (inverse Bremsstrahlung) in the high density nanoplasma, as is seen in solid target laser plasmas. Above threshold ionization heating [38] is also included, but its contribution is small (<100 eV). The collisional heating of the cluster is calculated in the model as the heating of a uniform dielectric sphere in the time-varying electric field of the laser. Inside the dielectric sphere, the electric field is [39]

see formula (3) [TD69.pdf, page 313]

where E_{0} is the external field and the plasma dielectric constant is given by a Drude model

see formula (4) [TD69.pdf, page 313]

Here *n _{e}*,

*n*are the electron and critical plasma densities,

_{crit}*w*is the laser frequency and

*v*the electronâ€“ion collision frequency that is calculated from the Silin formulae [40]. When

*n*= 3

_{e}*n*, |e + 2| goes through a minimum and the field inside the cluster is greater than the external field. At this resonance, the cluster heating rate is also increased, even though the electronâ€“ion collision frequency is actually reduced. Another consequence of the geometry of the laserâ€“cluster interaction is that there is no heat conduction possible to surrounding â€˜â€˜coldâ€™â€™ material, as is the case in a bulk plasma, suggesting that very high plasma temperatures may be attained in the nanoplasma. [TD69.pdf, page 313]

_{crit}See Also

**3.14 - Vortex Theory of Atomic Motions**
**13.04 - Atomic Subdivision**
**atomic**
**Atomic Cluster Ionization**
**Atomic Cluster X-Ray Emission**
**Atomic Clusters**
**Atomic Force**
**atomic mass**
**atomic number**
**atomic theory**
**atomic triplet**
**atomic weight**
**Clustered Water**
**diatomic**
**Figure 13.06 - Atomic Subdivision**
**Force-Atomic**
**Formation of Atomic Clusters**
**Interaction of Intense Laser Pulses with Atomic Clusters - Measurements of Ion Emission Simulations and Applications** TD69.pdf
**InterAtomic**
**Laser Cluster Interactions**
**Law of Atomic Dissociation**
**Law of Atomic Pitch**
**Law of Oscillating Atomic Substances**
**Law of Pitch of Atomic Oscillation**
**Law of Variation of Atomic Oscillation by Electricity**
**Law of Variation of Atomic Oscillation by Sono-thermism**
**Law of Variation of Atomic Oscillation by Temperature**
**Law of Variation of Atomic Pitch by Electricity and Magnetism**
**Law of Variation of Atomic Pitch by Rad-energy**
**Law of Variation of Atomic Pitch by Temperature**
**Law of Variation of Pitch of Atomic Oscillation by Pressure**
**Models of Laser Cluster Interactions**
**monatomic**
**Nanoplasma**
**subatomic**