Focused Laser Spike Dewetting as a Rheology Method for Soft Matter Thin Films

<div>Focused laser spike (FLaSk) dewetting employs a localized heat source to create thermocapillary induced trench-ridge morphologies. By using a universal heating substrate to create a material independent thermal profile coupled with optical microscopy, we have studied the dewetted ridge feature for several distinct glassy thin films. The evolution of the ridge's radius over time can be modeled using stretched exponential functions to derive a maximum dewetted radius and a characteristic decay time. The characteristic decay time shows a super-Arrhenius behavior resembling viscosity change during the glass transition process. An effective viscosity is defined by balancing the thermocapillary Marangoni stress using the mean temperature in the melt pool, indicating clear signature of composition. In this way, we have demonstrated that FLaSk dewetting as a rheology</div><div>method can be employed for high-throughput analysis of glassy thin film materials at high temperature and shear.</div>

Focused Laser Spike Dewetting as a Rheology Method for Soft Matter Thin Films

<div>Focused laser spike (FLaSk) dewetting employs a localized heat source to create thermocapillary induced trench-ridge morphologies. By using a universal heating substrate to create a material independent thermal profile coupled with optical microscopy, we have studied the dewetted ridge feature for several distinct glassy thin films. The evolution of the ridge's radius over time can be modeled using stretched exponential functions to derive a maximum dewetted radius and a characteristic decay time. The characteristic decay time shows a super-Arrhenius behavior resembling viscosity change during the glass transition process. An effective viscosity is defined by balancing the thermocapillary Marangoni stress using the mean temperature in the melt pool, indicating clear signature of composition. In this way, we have demonstrated that FLaSk dewetting as a rheology</div><div>method can be employed for high-throughput analysis of glassy thin film materials at high temperature and shear.</div>

Focused Laser Spike Dewetting as a Rheology Method for Soft Matter Thin Films

<div>Focused laser spike (FLaSk) dewetting employs a localized heat source to create thermocapillary induced trench-ridge morphologies. By using a universal heating substrate to create a material independent thermal profile coupled with optical microscopy, we have studied the dewetted ridge feature for several distinct glassy thin films. The evolution of the ridge's radius over time can be modeled using stretched exponential functions to derive a maximum dewetted radius and a characteristic decay time. The characteristic decay time shows a super-Arrhenius behavior resembling viscosity change during the glass transition process. An effective viscosity is defined by balancing the thermocapillary Marangoni stress using the mean temperature in the melt pool, indicating clear signature of composition. In this way, we have demonstrated that FLaSk dewetting as a rheology</div><div>method can be employed for high-throughput analysis of glassy thin film materials at high temperature and shear.</div>

Systematic study of magnetar outbursts

We present the results of a systematic study of all magnetar outbursts observed to date through a reanalysis of data acquired in about 1100 X-ray observations. We track the temporal evolution of the luminosity for all these events, model empirically their decays, and estimate the characteristic decay time-scales and the energy involved. We study the link between different parameters, and reveal several correlations between different quantities. We discuss our results in the framework of the models proposed to explain the triggering mechanism and evolution of magnetar outbursts.

POSSIBLE EVOLUTION OF DIM RADIO-QUIET NEUTRON STAR 1E 1207.4-5209 BASED ON A B-DECAY MODEL

Dim radio-quiet neutron star (DRQNS) 1E 1207.4-5209 is one of the most heavily examined isolated neutron stars. Wide absorption lines were observed in its spectrum obtained by both XMM-Newton and Chandra X-ray satellites. These absorption lines can be interpreted as a principal frequency centered at 0.7 keV and its harmonics at 1.4, 2.1 and possibly 2.8 keV. The principal line can be formed by resonant proton cyclotron scattering leading to a magnetic field which is two orders of magnitude larger than the perpendicular component of the surface dipole magnetic field (B) found from the rotation period (P) and the time rate of change in the rotation period [Formula: see text] of 1E 1207.4-5209. Besides, age of the supernova remnant (SNR) G296.5 + 10.0 which is physically connected to 1E 1207.4-5209 is two orders of magnitude smaller than the characteristic age [Formula: see text] of the neutron star. These huge differences between the magnetic field values and the ages can be explained based on a B-decay model. If the decay is assumed to be exponential, the characteristic decay time turns out to be several thousand years which is three orders of magnitude smaller than the characteristic decay time of radio pulsars represented in an earlier work. The lack of detection of radio emission from DRQNSs and the lack of point sources and pulsar wind nebulae in most of the observed SNRs can also be partly explained by such a very rapid exponential decay. The large difference between the characteristic decay times of DRQNSs and radio pulsars must be related to the differences in the magnetic fields, equation of states and masses of these isolated neutron stars.