Recent Results Melting Point Temperature Validation W Wire Heating

Recent Results—Melting Point Temperature Validation (W Wire Heating) W Mo Ni Fe Pt

Recent Hardware Improvements— Sketch of Laser Heating System in 12. 2. 2 Hutch Top Shelf-Map View TR Mirror New-Power Control Setup YLF Beam Splitter BE pbc *Spectrometer alignment Spectrometer corrected! wp Beam Steerer (top of periscope) bd ~ 0. 5 meter Spectrometer 50: 50 Sampler ½”CCD Cam TV T. R Mirror iris aperture IR filter ~0. 5 meter 1 m lens TR & YLF Mirrors 50: 50 Sampler TV iris aperture IR filter T. R Mirror 1 m lens Quantronix Falcon 217 D Nd: YLF 1053 nm 50 W TEM 01 laser on lower shelf

Recent Results—Melting Point Temperature Validation (Laser Heating 25 mm Fe foil)

Recent Results—Melting Point Temperature Validation (Laser Heating 25 mm Fe foil) (temperature/coupling varied at constant waveplate voltage)

Recent Results—Melting Point Temperature Validation (Laser Heating 25 mm Fe foil) (~ 2 mm/pixel)

Recent Progress—Software Improvements: *l-range user-changeable *fits weighted by SR

Recent Progress—Visual Observation of Melt and In-Situ Diffraction Large hotspot (FWHM > 40 microns) during laser heating of Fe foil at ambient x-ray beamsize (~ 12 mm) Fe foil (25 mm) mounted btwn glass slides (~ 120 mm) Pt in Al 2 O 3

Future Plans-- High-Temperature Laser Heated In-Situ Diffraction Simultaneous diffraction and heating from Pt/Al 2 O 3 DACs has not gone well. Samples not coupling well and visualizing samples difficult. Max Temps for Pt in DAC below Tm. Last beamtime used to diffract from ambient Fe foil. No clear liquid diffraction from Fe, but signal from high temperature g-phase and d-phase…more time for xrd analysis needed. Also, the sample moves/migrates during heating, making steady measurements challenging Before Heating After Heating

Future Plans-- High-Temperature Laser Heated In-Situ Diffraction Plans: Complete Validation of Temperature Determination: 1)Ambient Resistive Melting (Done) 2)Ambient Laser Melting (Fe done, Pt next) also w/x-rays 3)Comparison of Pt melt curve (better DAC loadings) ES 2 paper SRI proceedings Continue software improvements more automated more analysis tools New optics *obj. lens –possible source of coma *glass pellicle b. s. —improve visualization) New laser *diode fiber lasers Hardware reconfig motorized slits simpler optic path (laser steering independent of visualization and temperature determination optics) optics ray tracing