Helyum Atomunun İkili Uyarılma-İyonlaşma Rezonans Profillerinin 10o-80o Açı Aralığındaki Değişimlerinin İncelenmesi

Year 2020, Volume: 15 Issue: 2, 295 - 306, 29.11.2020

Nurçin Kayar , Zehra Nur Özer

https://doi.org/10.29233/sdufeffd.821479

Abstract

Bu çalışmada, elektron spektrometresi kullanılarak, Helyum (He) atomunun rezonans düzeylerinin açısal değişimleri ölçülmüştür. 200 eV enerjili elektron demeti, yüksek vakum ortamında He atomları ile çarpıştırılarak koparılan ve saçılan elektronlar dedekte edilmiştir. Elektron spektrometresi deney düzeneği; vakum sistemi, elektron tabancası, hedef gaz He, saçılan ve koparılan elektronları dedekte eden iki elektron enerji analizörü, elektron dedektörleri, sinyal işleme ünitesi ve Faraday Elektron Toplayıcıdan (FET) oluşmaktadır. Bu çalışmada, soygaz element serisinde olan Helyum atomunun kendiliğinden iyonlaşma enerji seviyeleri 10o-80o açı aralığında incelenmiştir. Enerji değerleri 32,5-35 eV olarak alınmıştır. Küçük açılarda rezonans profillerinin simetri durumlarının daha baskın olduğu görülürken, büyük açılara doğru kayıldıkça hem simetrik hem asimetrik yapıda oldukları görülmüştür.

Keywords

Elektron spektrometresi, İkili uyarılma, Kendiliğinden iyonlaşma, Rezonans düzeyleri, Helyum atomu

Supporting Institution

AKÜ-BAPK

Project Number

15.FenBil.14, 15.Hız.Des.132, 18.KARİYER.178

Investigation of Double Excitation- Ionization Resonance Profiles of Helium Atom at 10o-80o Angular Range

Abstract

In this work, the angular variations of the He atom for the resonance levels were experimentally measured by electron spectrometer. 200 eV energetic electron beam collided with Helium (He) gas in high vacuum and scattered electrons were detected. Measurements were taken for angular variation for fixed incident electron energy. The experimental setup in the electron collision laboratory consists of an electron gun, as target He atom, two electron energy analyzers, electron detectors, signal processing units and Faraday Electron Cup (FEC). Here, the auto ionization energy levels of the He atom (in the rare gas element series) for 10o-800 angular range were examined. Differential cross section measurements (DCS) of resonance energy levels were inspected for 32,5-35 eV. Although the symmetry states of resonance profiles are more dominant in the small angle range, both symmetrical and asymmetrical structures are observed for larger angles.

Keywords

Electron spectrometer, Double excitation, Autoionization, Resonance profiles, Helium atom

Project Number

15.FenBil.14, 15.Hız.Des.132, 18.KARİYER.178

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