Spectral investigation of the interstellar extinction curve

العناوين الأخرى

تحقيق طيفي لمنحني الاعتتام للمادة ما بين النجوم

مقدم أطروحة جامعية

Husayn, Haydar Rida

مشرف أطروحة جامعية

Jumah, Nazim Hasan Haydar
Karim, Layth Mahmud

أعضاء اللجنة

Abbud, Kamal Muhammad
al-Rikabi, Ali Talib Muhammad Hasan
Salih, Muhammad A. B.

الجامعة

جامعة بغداد

الكلية

كلية العلوم

القسم الأكاديمي

قسم الفلك و الفضاء

دولة الجامعة

العراق

الدرجة العلمية

ماجستير

تاريخ الدرجة العلمية

2013

الملخص الإنجليزي

The aim of this work is to explain the nature of the interstellar matter, investigating the interstellar extinction curve by determining the molecules mixtures thought to be responsible for the absorption features in the wavelength range (8.5-12.5) μm and trying to prove that this mixture is probably composed of organic or inorganic materials or a mixture of them.

The chemical reaction in the interstellar matter and the formation of the molecules have taken a considerable attention in order to understand the mechanism of physical condition led to the formation of chemical compounds that responsible for the absorption features in the wavelength range (8.5-12.5) μm.

Laboratory samples were prepared for different organic and inorganic materials and then the transmittance is measured for each sample as a function of a wave number (1/cm) using FTIR spectrophotometer.

The transmittance values as a function of wave number are transformed to flux density as a function of wavelength (μm) using Beer– Lambert law’s and Planck’s function .This process enabled us to have freedom in preparing the models.

Many attempts have been done for preparing the model by changing the materials in the desired mixture as well as their weight ratios seeking best fitting with observation data of trapezium Nebula.

Six preparing sample models have been examined using the old technique (flux summation procedure) and four models also examined using our new approach (flux convolution procedure).The results indicate that the convolution approach (new procedure) show higher cross correlation coefficients.

This indicates the superiority of the new suggested approach

التخصصات الرئيسية

الفلك و علومه

عدد الصفحات

117

قائمة المحتويات

• APA
• MLA
• AMA

لغة النص

الإنجليزية

نوع البيانات

رسائل جامعية

رقم السجل

BIM-604223