1 Laser Background 2 Apparatus Overview 3 Ion Beam Properties A Energy Spread B Spatial Spread 4 Xe + & Xe 2+ In Laser 5 Z-Scan of Laser Focus 6 Summary Multiple Charged Ions Production From Xe + & Xe 2+ In Intense Laser Field BY M.SURESH
Femtosecond Lasers Ti: Sapphire at 800 nm (1.6 eV) Chirped Pulse Amplification Terrawatt (10 12 W) Lasers ASTRA ~10 mJ in ~10 fs High field physics > Wcm -2 1 au = 3 x Wcm -2 Repetition rate 10 Hz
Apparatus Overview
Laser Alignment Shadow Exit Window Entrance Window Two Wire Crosses Laser Beam
Analyzer
Analyzer Plate Scan for Multiply Charged Ions of and Xe + Voltage (V) Xe 2+ Voltage (V) Time of Flight
Spatial Spread Measurement 1 mm Aperture 0.5 mm Aperture 0.13 mm Slit ION BEAM CHARACTERIZATION
Spatial Spread Scan of He + Ion Beam
Spatial Spread of He + and Ar + at Different Ion Beam Energies Type of IonEnergy (KeV)Spatial Spread(mm) He Ar Spatial Spread Depends On Energy And Mass Of The Beam
Spatial Spread Scan of He + Ion Beam Selected by 1mm & 2mm Apertures Current Decreases From 300nA To 120nA Current Decreases From 300nA To 120nA 2 mm Aperture 1 mm Aperture Ion beam Current (nA) Slit Position (mm)
Spatial Spread of He + and Ar + (3keV) With 1mm & 2mm Apertures Spatial Spread Depends on Aperture Size Type of Ion 2mm Aperture 1mm Aperture He Ar
Spatial Spread of He + Ion Beam at Different Focusing Conditions Energy Without Focusing Focused Through 0.5mmAperture 1keV1.27mm0.41mm 3keV0.97mm0.34mm
Energy spread Energy Spread 1mm Aperture 1kV Energy Different Discharge Constant Pressure Different Pressure Constant Discharge 2kV Energy 2mm Aperture
Energy Spread of 1keV and 2keV Ar mm Aperture Nergy Spread(eV)Nergy Spread(eV) Discharge Voltage (V) Energy Spread (eV) 1KeV 2KeV
ISS Z-Scan
Z-scan of Xe 3+ from Xe 2+ Z -scan of Xe 4+ from Xe E E-9 0.0E+0 1.0E-9 2.0E-9 3.0E-9 4.0E-9 5.0E-9 6.0E-9 7.0E-9 8.0E-9 9.0E-9 1.0E Signal Z-Position (mm)
Z-scan of Xe 6+ from Xe 2+ Z-scan of Xe 7+ from Xe 2+ Z-Position (mm) Signal 2.5E E E E+0 2.5E E E E-9 1.3E-9 1.5E-9 1.7E-9 2.0E-9 2.3E
Summary First experimental results on Xe 2+ in intense laser field Less Than 2% Energy spread 0.34mm Spatial Spread Up to Xe 7+ from both Xe + and Xe 2+