Dutch astronomers C.P. de Vries and E. Costantini, both of SRON/Utrecht University Netherlands, used the Reflection Grating Spectrometer onboard the XMM-Newton satellite to obtain high-quality X-ray spectra of Scorpius X-1, one of the brightest X-ray sources in the sky, located about 2800 parsecs from Earth.
Dutch astronomers C.P. de Vries and E. Costantini, both of SRON/Utrecht University Netherlands, used the Reflection Grating Spectrometer onboard the XMM-Newton satellite to obtain high-quality X-ray spectra of Scorpius X-1, one of the brightest X-ray sources in the sky, located about 2800 parsecs from Earth. For the first time, they have found clear evidence of an extended X-ray absorption fine structure (EXAFS) signature coming from the dust seen toward a celestial source.
EXAFS is a powerful tool for studying the grains in the interstellar medium. It is based upon the phenomenon that X-ray photons can eject electrons from atoms inside solid particles, which in turn can be backscattered onto the emitting atom by atoms in their immediate neighborhood. This causes characteristic sinusoidal absorption features in the X-ray spectrum of a distant source that depend on the structure of the absorbing solid material.
EXAFS has a major advantage over infrared (IR) spectroscopy, which can also be used to study crystalline dust, in that in can probe the solid matter along the line of sight at the level of the atomic structure. IR spectroscopy provides information at the mineralogical level. As a result, EXAFS gives a more detailed picture of the chemical composition and atomic structure of amorphous grains than is possible with IR spectroscopy.
Getting accurate IR spectra on monolayer of molecules
April 18th 2024Creating uniform and repeatable monolayers is incredibly important for both scientific pursuits as well as the manufacturing of products in semiconductor, biotechnology, and. other industries. However, measuring monolayers and functionalized surfaces directly is. difficult, and many rely on a variety of characterization techniques that when used together can provide some degree of confidence. By combining non-contact atomic force microscopy (AFM) and IR spectroscopy, IR PiFM provides sensitive and accurate analysis of sub-monolayer of molecules without the concern of tip-sample cross contamination. Dr. Sung Park, Molecular Vista, joined Spectroscopy to provide insights on how IR PiFM can acquire IR signature of monolayer films due to its unique implementation.
Hot News on Agilent LDIR, New Developments, and Future Perspective
April 25th 2024Watch this video featuring Darren Robey and Dr. Wesam Alwan from Agilent Technologies to gain insights into the future trends shaping microplastics research and the challenges of their characterization. Discover the essential components necessary for accurate microplastics analysis and learn how the Agilent 8700 LDIR system addresses these challenges. Offering rapid and precise analysis capabilities, along with easy sample preparation methods that minimize contamination, the Agilent 8700 LDIR system is at the forefront of advancing microplastics research.