Multi-object spectroscopy

Keywords Micro-optics, MOEMS, multi-object spectroscopy, adaptive optics, astronomi-... 

Thanks to its multiplexing capabilities, Multi-Object Spectroscopy (MOS)... 

In the design of MOEMS components, various parameters have to be tuned. These parameters differ according to the functionality of the component. We will consider two different family of devices, programmable slits for Multi-Object Spectroscopy, including Micro-Mirror Arrays (MMA) and Micro-Shutters Arrays (MSA), and Micro-Deformable Mirrors (MDM) for Adaptive Optics systems. 

Programmable multi-slit mask for Multi-Object Spectroscopy... 

Figure 1. Principle of Multi-Object Spectroscopy using a Micro-Mirror Array. MMA array in the park position and in action...

Micro-Opto-Electro-Mechanical Systems (MOEMS) will be widely integrated in new astronomical instruments for future Extremely Large Telescopes, as well as for existing lOm-class telescopes. The two major applications are programmable slit masks for Multi-Object Spectroscopy (see Ch. 12) and deformable mirrors for Adaptive Optics systems. Eirst prototypes have shown their capabilities. However, big efforts have stiU to be done in order to reach the requirements and to realize reliable devices. 

R. Pallavicini, et al. Multi-object spectroscopy of open clusters with FLAMES preliminary GTO results . In This volume. 

Multi-Object Spectroscopy of Open Clusters with FLAMES Preliminary GTO Results... 

It is just a half-century ago that the concept of real abundance variations became well-established. It is less that 50 years since the famous B2FH paper was published. Quantitative CCD-based spectroscopy is only some 20 years old, while quantitative multi-object spectroscopy has really begun only in the last decade. These rapid observational advances were enabled by impressive advances in instrumentation, combined with increasing software power and complexity. In parallel, significant advances in stellar atmospheric modelling, and the requisite atomic and molecular data, have allowed analyses of superb precision for large numbers of stars. 

A. Bianco, C. Bertarelli, M. C. Gallazzi, G. Zerbi, E. Giro, E. Molinari, Smart focal plane masks rewritable photochromic films for astronomical multi-object spectroscopy, Astron. Nachr., 326, 370-374 (2005). 

We constructed a liquid nitrogen cooled infrared camera (PICNIC), whidi uses a NICM0S3 256 X 256 format array detector and a new optical syst which consists of reflective optics (Fig. 1). Two additional componoits, a rotating half wave plate polarimeter and a prism, can be attadied in front of the camera, enabling us to obtain imaging polarimetry and multi-object spectroscopy. 

We also designed a new prism to be placed in front of the camera, whidi can be used as an objective prism and enable us to make simultaneous multi object low resolution spectroscopy for quick dassification of crowded field objects, although the collected badcground radiation reduces the sensitivity. The prism consists of 4 components made of different optical material. 

Identification of the intermediates in a multi-step reaction is the major objective of studies of reaction mechanisms. It is most useful to study intermediates present in low concentrations without chemical interference with the reacting system, i.e. by rapid spectroscopic methods. The most common methods in organic chemistry include ultraviolet-visible (UV-VIS), IR, and EPR spectroscopy. In principle, all other spectroscopic methods for the detection of reaction intermediates are also applicable provided that they are fast enough to monitor the intermediate and able to provide sufficient structural information to assist in the identification of the transient species. 

Spectroscopy has become a powerful tool for the determination of polymer structures. The major part of the book is devoted to techniques that are the most frequently used for analysis of rubbery materials, i.e., various methods of nuclear magnetic resonance (NMR) and optical spectroscopy. One chapter is devoted to (multi) hyphenated thermograviometric analysis (TGA) techniques, i.e., TGA combined with Fourier transform infrared spectroscopy (FT-IR), mass spectroscopy, gas chromatography, differential scanning calorimetry and differential thermal analysis. There are already many excellent textbooks on the basic principles of these methods. Therefore, the main objective of the present book is to discuss a wide range of applications of the spectroscopic techniques for the analysis of rubbery materials. The contents of this book are of interest to chemists, physicists, material scientists and technologists who seek a better understanding of rubbery materials. 

Alternatively, hydrophilic multi-hydroxyl poly(GMA-OH)-grafted MWCNTs could be converted into multicarboxyl polymer-functionalized CNTs by reaction with succinic anhydride and then used as templates to efficiently sequestrate metal ions such as Ag", Co ", Ni , Au , La and (Scheme 5.3), generating MWCNT-polymer/metal hybrid nanocomposites, nanowires or necklace-like nanostructures, depending on the grafted polymer content and the nature of the captured metals. The combination of SEM, TEM and energy dispersive spectroscopy (EDS) characterizations demonstrated the structure and elements of the hybrid nano-objects. 

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