Journal articles: 'Light beam spectroscopy'

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Lu, Fanfan, Tengxiang Huang, Lei Han, Haisheng Su, Heng Wang, Min Liu, Wending Zhang, Xiang Wang, and Ting Mei. "Tip-Enhanced Raman Spectroscopy with High-Order Fiber Vector Beam Excitation." Sensors 18, no. 11 (November 9, 2018): 3841. http://dx.doi.org/10.3390/s18113841.

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We investigated tip-enhanced Raman spectra excited by high-order fiber vector beams. Theoretical analysis shows that the high-order fiber vector beams have stronger longitudinal electric field components than linearly polarized light under tight focusing conditions. By introducing the high-order fiber vector beams and the linearly polarized beam from a fiber vector beam generator based on an electrically-controlled acoustically-induced fiber grating into a top-illumination tip-enhanced Raman spectroscopy (TERS) setup, the tip-enhanced Raman signal produced by the high-order fiber vector beams was 1.6 times as strong as that produced by the linearly polarized light. This result suggests a new type of efficient excitation light beams for TERS.

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Austregesilo, Alexander. "Light-Meson Spectroscopy at GlueX." International Journal of Modern Physics: Conference Series 46 (January 2018): 1860029. http://dx.doi.org/10.1142/s2010194518600297.

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GlueX at Jefferson Lab aims to study the light meson spectrum with an emphasis on the search for light hybrid mesons. To this end, a linearly-polarized [Formula: see text]GeV photon beam impinges on a hydrogen target contained within a hermetic detector with near-complete neutral and charged particle coverage. In 2016, the experiment completed its commissioning and subsequently started to take data in its design configuration. With the size of the data set so far, GlueX already exceeds previous experiments for polarized photoproduction in this energy regime. A selection of early results will be presented, focusing on beam asymmetries for pseudo-scalar and vector mesons. The potential to make significant contributions to the field of light-meson spectroscopy is highlighted by the observation of several known meson resonances. Furthermore, the strategy to map the light meson spectrum with amplitude analysis tools will be outlined.

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Ghosh, Sandip, and B. M. Arora. "Photoreflectance spectroscopy with white light pump beam." Review of Scientific Instruments 69, no. 3 (March 1998): 1261–66. http://dx.doi.org/10.1063/1.1148761.

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García-Cabrera, Ana, Roberto Boyero-García, Óscar Zurrón-Cifuentes, Javier Serrano, Julio San Román, Carlos Hernández-García,, and Luis Plaja. "High-harmonic spectroscopy of solids driven by structured light." EPJ Web of Conferences 287 (2023): 11006. http://dx.doi.org/10.1051/epjconf/202328711006.

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Understanding high-order harmonic generation (HHG) from solid targets holds the key of potential technological innovations in the field of high-frequency coherent sources. Solids present optical nonlinearities at lower driving intensities, and harmonics can be efficiently emitted due to the increased electron density in comparison with the atomic and molecular counterparts. In addition, crystalline solids introduce a new complexity, as symmetries play a role in the anisotropic character of the optical response. An extraordinary playground is, therefore, the scenario in which solids are driven by vector beams, since crystal symmetries can be directly coupled with the topology of the driving laser beam. In this contribution we analyze the topological properties of the HHG radiation emitted by a single-layer graphene sheet driven by a vector beam. We show that the harmonic field is a complex combination of vortices, whose geometrical properties hold information about the details of the non-linear response of the crystal. We demonstrate, therefore, that the analysis of the topological structure of the harmonic field can be used as a spectroscopic measurement technique, paving the way of topological spectroscopy as a new strategy for the characterization of the optical response of macroscopic targets.

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MacFarlane, J. J., P. Wang, J. E. Bailey, T. A. Mehlhorn, and R. J. Dukart. "Plasma diagnostics using Kα satellite emission spectroscopy in light ion beam fusion experiments." Laser and Particle Beams 13, no. 2 (June 1995): 231–41. http://dx.doi.org/10.1017/s0263034600009356.

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Kα satellite spectroscopy can be a valuable technique for diagnosing conditions in high energy density plasmas. Kα emission lines are produced in intense light ion beam plasma interaction experiments as 2p electrons fill partially open Is shells created by the ion beam. In this paper, we present results from collisional-radiative equilibrium (CRE) calculations which show how Kα emission spectroscopy can be used to determine target plasma conditions in intense lithium beam experiments on Particle Beam Fusion Accelerator-II (PBFAII) at Sandia National Laboratories. In these experiments, 8–10 MeV lithium beams with intensities of 1–2 TW/cm2 irradiate planar multilayer targets containing a thin Al tracer. Kα emission spectra are measured using an X-ray crystal spectrometer with a resolution of λ/∆λ = 1200. The spectra are analyzed using a CRE model in which multilevel (NL ∼ 103) statistical equilibrium equations are solved self-consistently with the radiation field and beam properties to determine atomic level populations. Atomic level-dependent fluorescence yields and ion-impact ionization cross sections are used in computing the emission spectra. We present results showing the sensitivity of the Kα emission spectrum to temperature and density of the Al tracer. We also discuss the dependence of measured spectra on the X-ray crystal spectral resolution, and how additional diagnostic information could be obtained using multiple tracers of similar atomic number.

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Eriksson, Ronja, Per Gren, Mikael Sjödahl, and Kerstin Ramser. "Investigation of the Spatial Generation of Stimulated Raman Scattering Using Computer Simulation and Experimentation." Applied Spectroscopy 76, no. 11 (October 24, 2022): 1307–16. http://dx.doi.org/10.1177/00037028221123593.

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Stimulated Raman scattering is a phenomenon with potential use in providing real-time molecular information in three-dimensions (3D) of a sample using imaging. For precise imaging, the knowledge about the spatial generation of stimulated Raman scattering is essential. To investigate the spatial behavior in an idealized case, computer simulations and experiments were performed. For the computer simulations, diffraction theory was used for the beam propagation complemented with nonlinear phase modulation describing the interaction between the light and matter. For the experiments, a volume of ethanol was illuminated by an expanded light beam and a plane inside the volume was imaged in transmission. For generating stimulated Raman scattering, a pump beam was focused into this volume and led to a beam dump after passing the volume. The pulse duration of the two beams were 6 ns and the pump beam energy ranged from 1 to 27 mJ. The effect of increasing pump power on the spatial distribution of the Raman gain and the spatial growth of the signal at different interaction lengths between the beam and the sample was investigated. The spatial width of the region where the stimulated Raman scattering signal was generated for experiments and simulation was 0.21 and 0.09 mm, respectively. The experimental and simulation results showed that most of the stimulated Raman scattering is generated close to the pump beam focus and the maximum peak of the Stokes intensity spatially comes shortly after the peak of the pump intensity.

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Ranasinghe, Meenakshi, Md Arifuzzaman, Apeksha C. Rajamanthrilage, W. R. Willoughby, Ashley Dickey, Colin McMillen, Joseph W. Kolis, Mark Bolding, and Jeffrey N. Anker. "X-ray excited luminescence spectroscopy and imaging with NaGdF4:Eu and Tb." RSC Advances 11, no. 50 (2021): 31717–26. http://dx.doi.org/10.1039/d1ra05451a.

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We synthesized and characterized Eu and Tb doped NaGdF4 nanophosphors which generate visible light when excited by a focused X-ray beam. High resolution images were acquired through tissue by measuring light intensity vs. X-ray beam position.

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Donaldson, Paul M., Russell F. Howe, Alexander P. Hawkins, Mike Towrie, and Gregory M. Greetham. "Ultrafast 2D-IR spectroscopy of intensely optically scattering pelleted solid catalysts." Journal of Chemical Physics 158, no. 11 (March 21, 2023): 114201. http://dx.doi.org/10.1063/5.0139103.

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Solid, powdered samples are often prepared for infrared (IR) spectroscopy analysis in the form of compressed pellets. The intense scattering of incident light by such samples inhibits applications of more advanced IR spectroscopic techniques, such as two-dimensional (2D)-IR spectroscopy. We describe here an experimental approach that enables the measurement of high-quality 2D-IR spectra from scattering pellets of zeolites, titania, and fumed silica in the OD-stretching region of the spectrum under flowing gas and variable temperature up to ∼500 ◦C. In addition to known scatter suppression techniques, such as phase cycling and polarization control, we demonstrate how a bright probe laser beam comparable in strength with the pump beam provides effective scatter suppression. The possible nonlinear signals arising from this approach are discussed and shown to be limited in consequence. In the intense focus of 2D-IR laser beams, a free-standing solid pellet may become elevated in temperature compared with its surroundings. The effects of steady state and transient laser heating effects on practical applications are discussed.

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Montalvo, Joseph G., Sherman E. Faught, and Steven M. Buco. "An Investigation of the Relationship between Cotton Fineness and Light Scattering from Thin Webs as Measured by Near-Infrared Transmission Spectroscopy." Applied Spectroscopy 43, no. 8 (November 1989): 1459–71. http://dx.doi.org/10.1366/0003702894204353.

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Near-infrared transmission spectroscopy (NITS) is applied to thin cotton webs to measure fiber fineness (expressed either as specific surface—the external surface area per unit weight of fiber—or as cross-sectional perimeter). We report here the development and successful testing of a mathematical model that predicts a linear relationship between fineness and light-scattering intensity (optical density, log 1/ T) by a thin cotton web. With a thin web of fibers in the light beam, absorption of photons out of the beam is negligible. When the detector is placed several inches from the web, only the photons passing between the fibers strike the light detector. Photons that strike a fiber are scattered out of the light beam and away from the detector. Thus the fineness of the fiber controls the propagation of light to the detector. The premise that specific surface is proportional to optical density when the weight of fiber in the light beam is constant is shown experimentally (probability, p < 0.0045). Also, the premise that perimeter is proportional to optical density when the total length of fiber in the light beam is constant is shown experimetally ( p < 0.0070). These results are based on analysis of 9 cottons; 810 webs were produced, computer sorted by weight, and the scatter spectra recorded for 360 webs.

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Yamada, Norifumi L. "Novel idea of neutron polychromator and application for reflectometry and spectroscopy." EPJ Web of Conferences 286 (2023): 03009. http://dx.doi.org/10.1051/epjconf/202328603009.

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Historically, two methods have been used to determine the wavelength of neutrons: (i) a timeof-flight method that separates the velocity of pulsed neutrons by the flight time; and (ii) a method utilizing Bragg reflection by a monochromator, such as a single crystal or multilayer mirror. The former cannot be applied to electromagnetic waves because the light velocity is constant and independent of the wavelength, whereas “polychromators” such as prisms and gratings, which separate wavelengths via chromatic dispersion, are typically used in the infrared to soft X-ray range. Although polychromators require collimated beams to separate wavelengths with sufficient resolution, this aspect does not affect laser and synchrotron light because they are naturally collimated. Herein, we propose a novel idea of a neutron polychromator utilizing an elliptical multilayered mirror that can be applied to a wide beam with a large beam divergence. In addition, examples of reflectometer and spectrometer applications are presented.

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Cignoli, F., S. De Iuliis, and G. Zizak. "A Webcam as a Light Probe Beam Profiler." Applied Spectroscopy 58, no. 11 (November 2004): 1372–75. http://dx.doi.org/10.1366/0003702042475439.

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Teboul, V., J. L. Godet, and Y. Le Duff. "Collection Angle Dependence of the Depolarization Ratio in Light-Scattering Experiments." Applied Spectroscopy 46, no. 3 (March 1992): 476–78. http://dx.doi.org/10.1366/0003702924125285.

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We have calculated, in a typical scattering experiment, the exact value of the intensity scattered by a sample for any value of the collection angle of the scattered beam and for different beam polarizations.

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Ramola, R. C., and Subhash Chandra. "Ion Beam Induced Modifications in Conducting Polymers." Defect and Diffusion Forum 341 (July 2013): 69–105. http://dx.doi.org/10.4028/www.scientific.net/ddf.341.69.

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High energy ion beam induced modifications in polymeric materials is of great interest from the point of view of characterization and development of various structures and filters. Due to potential use of conducting polymers in light weight rechargeable batteries, magnetic storage media, optical computers, molecular electronics, biological and thermal sensors, the impact of swift heavy ions for the changes in electrical, structural and optical properties of polymers is desirable. The high energy ion beam irradiation of polymer is a sensitive technique to enhance its electrical conductivity, structural, mechanical and optical properties. Recent progress in the radiation effects of ion beams on conducting polymers are reviewed briefly. Our recent work on the radiation effects of ion beams on conductive polymers is described. The electrical, structural and optical properties of irradiated films were analyzed using V-I, X-Ray diffraction (XRD), scanning electron microscopy (SEM), UV-Visible spectroscopy and Fourier transform infrared spectroscopy methods.

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Bailey, J. E., A. B. Filuk, A. L. Carlson, D. J. Johnson, P. Lake, E. J. McGuire, T. A. Mehlhorn, et al. "Basic and applied atomic spectroscopy in high-field ion diode acceleration gaps." Laser and Particle Beams 14, no. 4 (December 1996): 543–53. http://dx.doi.org/10.1017/s0263034600010260.

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Achieving inertial confinement fusion using a light-ion-beam driver requires continued improvement in understanding ion diode physics. The power delivered to a light-ion beam target is strongly influenced by the evolution of the charge-particle distributions across the ion beam acceleration gap. Our strategy is to determine this evolution from time- and space-resolved measurements of the electric field using Stark-shifted line emission. In addition to diode physics, the unique high-field (∼10 MV/cm, ∼6T) conditions in present experiments offer the possibility to advance basic atomic physics, for example by measuring field ionization rates for tightly bound low-principal-quantum-number levels. In fact, extension of atomic physics into the high-field regime is required for accurate interpretation of diode physics measurements. This paper describes progress in ion diode physics and basic atomic physics, obtained with visible-light atomic spectroscopy measurements in the ∼20 TW Particle Beam Fusion Accelerator II ion diode.

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Heidbrink, W. W., G. R. McKee, D. R. Smith, and A. Bortolon. "‘Beam-emission spectroscopy’ diagnostics also measure edge fast-ion light." Plasma Physics and Controlled Fusion 53, no. 8 (June 2, 2011): 085007. http://dx.doi.org/10.1088/0741-3335/53/8/085007.

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Barbisan, M., B. Zaniol, R. Pasqualotto, G. Serianni, and M. Ugoletti. "First results from beam emission spectroscopy in SPIDER negative ion source." Plasma Physics and Controlled Fusion 63, no. 12 (October 27, 2021): 125009. http://dx.doi.org/10.1088/1361-6587/ac2eb2.

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Abstract The SPIDER experiment, part of the neutral beam test facility at Consorzio RFX (Padua, Italy), is the prototype of the negative ion source for the ITER neutral beam injectors; the source is coupled to a 100 kV three-grid acceleration system. A beam emission spectroscopy (BES) diagnostic was installed in SPIDER to study and optimize the energy distribution, aim, uniformity and divergence of the H−/D− beam extracted from the source. The diagnostic is based on analysis of the Doppler shifted Hα /Dα light emitted in the interaction between the beam particles and the H 2/D 2 molecules of the background. In 2019 the BES diagnostic in SPIDER was installed and calibrated, allowing us to characterize the first hydrogen beams extracted from the SPIDER source, in cesium-free conditions. The number of active beamlets of which the beam was composed was reduced from 1280 to 80, affecting the BES diagnostic capabilities. This paper presents the BES diagnostic setup and discusses the first collected results. Under limited extracted current density (∼10 A m−2) and ion energy (⩽35 keV), no significant vertical beam deflection caused by the magnetic filter field in the source was detected. In some cases the beamlets were observed to be elongated in the horizontal direction; beamlet divergence values down to 20 mrad and 30 mrad e-folding were measured in the vertical and horizontal directions, respectively; the intensity of the Doppler shifted radiation was found to be strongly correlated to the beam current and to the beam divergence. The progressive compensation of beamlet deflections (caused by electron suppression filter fields), with increasing voltage in the extraction gap, was studied.

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Kozich, V. P., A. Marcano, F. E. Hernandez, and J. A. Castillo. "Dual-Beam Time-Resolved Z-Scan in Liquids to Study Heating Due to Linear and Nonlinear Light Absorption." Applied Spectroscopy 48, no. 12 (December 1994): 1506–12. http://dx.doi.org/10.1366/0003702944027741.

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Dual-beam extension of a Z-scan technique has been developed to study the thermal changes in the refractive index resulting from linear and nonlinear absorption in liquids. The experiments were carried out with nanosecond-pulsed Nd:YAG radiation and its second harmonic as the excitation sources and a He-Ne laser as the probe beam. The cw probe radiation enabled us to observe temporal dynamics of the refractive index variations, to select the thermal signal for Z-scan measurement and to measure absolute changes in the refractive index as small as 10−6 due to heating in a number of organic liquids. The temporal shape of the thermal signal is analyzed experimentally and theoretically both in weak and strong phase distortion of the probe wave. Gaussian approximation for the pump and probe beams and the Taylor series decomposition of nonlinear phase distortion term at the exit of the sample are used to describe the thermal signal and to fit experimental data to theoretical models.

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Christopher, Joshua, Masoud Taleb, Achyut Maity, Mario Hentschel, Harald Giessen, and Nahid Talebi. "Electron-driven photon sources for correlative electron-photon spectroscopy with electron microscopes." Nanophotonics 9, no. 15 (September 18, 2020): 4381–406. http://dx.doi.org/10.1515/nanoph-2020-0263.

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AbstractElectron beams in electron microscopes are efficient probes of optical near-fields, thanks to spectroscopy tools like electron energy-loss spectroscopy and cathodoluminescence spectroscopy. Nowadays, we can acquire multitudes of information about nanophotonic systems by applying space-resolved diffraction and time-resolved spectroscopy techniques. In addition, moving electrons interacting with metallic materials and optical gratings appear as coherent sources of radiation. A swift electron traversing metallic nanostructures induces polarization density waves in the form of electronic collective excitations, i.e., the so-called plasmon polariton. Propagating plasmon polariton waves normally do not contribute to the radiation; nevertheless, they diffract from natural and engineered defects and cause radiation. Additionally, electrons can emit coherent light waves due to transition radiation, diffraction radiation, and Smith-Purcell radiation. Some of the mechanisms of radiation from electron beams have so far been employed for designing tunable radiation sources, particularly in those energy ranges not easily accessible by the state-of-the-art laser technology, such as the THz regime. Here, we review various approaches for the design of coherent electron-driven photon sources. In particular, we introduce the theory and nanofabrication techniques and discuss the possibilities for designing and realizing electron-driven photon sources for on-demand radiation beam shaping in an ultrabroadband spectral range to be able to realize ultrafast few-photon sources. We also discuss our recent attempts for generating structured light from precisely fabricated nanostructures. Our outlook for the realization of a correlative electron-photon microscope/spectroscope, which utilizes the above-mentioned radiation sources, is also described.

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Mohr, Konstantin, Axel Buß, Zoran Andelkovic, Volker Hannen, Max Horst, Phillip Imgram, Kristian König, et al. "Collinear Laser Spectroscopy of Helium-like 11B3+." Atoms 11, no. 1 (January 11, 2023): 11. http://dx.doi.org/10.3390/atoms11010011.

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Collinear laser spectroscopy in the 1s2s3S1→1s2p3P0,2 transitions of helium-like 11B3+ was performed using the HITRAP beamline at the GSI Helmholtz Centre. The ions were produced in an electron beam ion source, extracted, and accelerated to a beam energy of 4 keV/q. Results agree with previous measurements within uncertainty. Thus, it was demonstrated that the metastable state in He-like ions is sufficiently populated to carry out collinear laser spectroscopy. The measurement is a pilot experiment for a series of measurements that will be performed at a dedicated collinear laser spectroscopy setup at TU Darmstadt with light helium-like ions.

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Oh, Seung Jae, Yoochan Hong, Ki-Young Jeong, Inhee Maeng, Jin-Suck Suh, Jaemoon Yang, and Yong-Min Huh. "Characterization of Proton-Irradiated Polyaniline Nanoparticles Using Terahertz Thermal Spectroscopy." Crystals 11, no. 7 (June 30, 2021): 765. http://dx.doi.org/10.3390/cryst11070765.

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In this study, we investigated the changes in the molecular structure of polyaniline (PANI) nanoparticles illuminated by a proton beam using terahertz (THz) thermal spectroscopy based on the terahertz time-domain spectroscopy technique. PANI nanoparticles in water were exposed to a proton beam of 35 MeV energy with a particle fluence of 1013 particles/cm2. The photothermal properties of this solution of PANI nanoparticles were characterized using THz thermal spectroscopy. We measured the changes in the amplitudes of the reflected THz pulses to identify the variations in temperature induced by the photothermal effects of the PANI nanoparticle solution. The amplitude of a reflected THz pulse of the PANI solution not exposed to the proton beam increased when illuminated by an infrared light source, whereas that of THz signals of the PANI solution exposed to the proton beam hardly exhibited any changes. This implies that the molecular structure of PANI nanoparticles can be varied by a proton beam with a particle fluence above 1013 particles/cm2.

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Mirbagheri, Mahya, Naser Hakimi, Elias Ebrahimzadeh, and S. Kamaledin Setarehdan. "Simulation and in vivo investigation of light-emitting diode, near infrared Gaussian beam profiles." Journal of Near Infrared Spectroscopy 28, no. 1 (November 1, 2019): 37–50. http://dx.doi.org/10.1177/0967033519884209.

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Near infrared spectroscopy is an optical imaging technique which offers a non-invasive, portable, and low-cost method for continuously measuring the oxygenation of tissues. In particular, it can provide the brain activation through measuring the blood oxygenation and blood volume in the cortex. Understanding and then improving the spatial and depth sensitivity of near infrared spectroscopy measurements to brain tissue are essential for designing experiments as well as interpreting research findings. In this study, we investigate the effect of applying two common light beam profiles including Uniform and Gaussian on the penetration depth of an LED-based near infrared spectroscopy. In this regard, two Gaussian profiles were produced by adjusting plano-convex and bi-convex lenses and the Uniform profile was provided by applying a flat lens. Two experiments were conducted in this study. First, a simulation experiment was carried out based on scanning the intra space of a liquid phantom by using static and pulsating absorbers to compare the penetration depth of the configurations applied on the LED-based near infrared spectroscopy with that of a laser-based near infrared spectroscopy. Second, to show the feasibility of the best proposed configuration applied, an in vivo experiment of stress assessment has been performed and its results have been compared with that results obtained by laser one. The results showed that the LED-based near infrared spectroscopy equipped with bi-convex lens provides a penetration depth and hence quality measurements of near infrared spectroscopy and its extracted heart rate variability signals as well as laser-based near infrared spectroscopy especially in the application of stress assessment.

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McGlone, V. A., H. Abe, and S. Kawano. "Kiwifruit Firmness by near Infrared Light Scattering." Journal of Near Infrared Spectroscopy 5, no. 2 (March 1997): 83–89. http://dx.doi.org/10.1255/jnirs.102.

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Kiwifruit firmness was estimated by scattering 864 nm laser light through the fruit to exiting angles at 20 to 55° around the circumference of the fruit from the incident beam. The intensity of scattered light emitted from the fruit increased with decreasing firmness, especially at larger angles. The intensity changes were modelled using an inverse power law relationship between the intensity and a distance factor D = sin(θ / 2), where θ is the exiting angle. With increasing firmness the proportionality constant S increases and the power coefficient of D, – n, decreases. The logarithm of S gave the best linear regression results against stiffness and rupture force; two standard measures of fruit firmness, with R2 values of 83% and 79%, respectively.

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Müller, Niklas, Lukas Brückner, and Marcus Motzkus. "Shaper-based infrared spectroscopy in a nonlinear Raman setup." EPJ Web of Conferences 205 (2019): 03016. http://dx.doi.org/10.1051/epjconf/201920503016.

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We present combined mid-infrared and nonlinear Raman spectroscopy in a single beam setup through the flexible control by sub 10 fs pulse shaping. Hence tuneable (>2000 cm-1), narrowband (<20 cm-1) infrared light is generated.

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Ahmed, Aftab, Yuanjie Pang, Ghazal Hajisalem, and Reuven Gordon. "Antenna Design for Directivity-Enhanced Raman Spectroscopy." International Journal of Optics 2012 (2012): 1–8. http://dx.doi.org/10.1155/2012/729138.

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Antenna performance can be described by two fundamental parameters: directivity and radiation efficiency. Here, we demonstrate nanoantenna designs in terms of improved directivity. Performance of the antennas is demonstrated in Raman scattering experiments. The radiated beam is directed out of the plane by using a ground plane reflector for easy integration with commercial microscopes. Parasitic elements and parabolic and waveguide nanoantennas with a ground plane are explored. The nanoantennas were fabricated by a series of electron beam evaporation steps and focused ion beam milling. As we have shown previously, the circular waveguide nanoantenna boosts the measured Raman signal by 5.5x with respect to a dipole antenna over a ground plane; here, we present the design process that led to the development of that circular waveguide nanoantenna. This work also shows that the parabolic nanoantenna produces a further fourfold improvement in the measured Raman signal with respect to a circular waveguide nanoantenna. The present designs are nearly optimal in the sense that almost all the beam power is coupled into the numerical aperture of the microscope. These designs can find applications in microscopy, spectroscopy, light-emitting devices, photovoltaics, single-photon sources, and sensing.

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Lankers, M., D. Göttges, A. Materny, K. Schaschek, and W. Kiefer. "A Device for Surface-Scanning Micro-Raman Spectroscopy." Applied Spectroscopy 46, no. 9 (September 1992): 1331–34. http://dx.doi.org/10.1366/0003702924123728.

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A simple but very efficient device for micro-Raman spectroscopy of highly absorbing solid samples is described. The device allows rapid scanning of the focused laser beam on the surface of a solid sample, which avoids heating of the sample. By means of a pair of computer-controlled piezo-translators, which are fixed to the microscope objective, the laser beam can be scanned in a great variety of traces, the scattered light of which is collected and optically transformed into a very small spot at the entrance slit of the spectrometer. The system is tested on highly absorbing (partially) polymerized diacetylene single crystals at low temperatures.

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Wolf, Ursula, Sabine Klein, Annegret Sandig, and Stephan Baumgartner. "Investigating homeopathic preparations with light spectroscopy." International Journal of High Dilution Research - ISSN 1982-6206 11, no. 40 (December 21, 2021): 117. http://dx.doi.org/10.51910/ijhdr.v11i40.584.

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Background Several series of experiments from our research group have shown ultraviolet (UV) light transmission of homeopathic preparations to slightly but significantly differ from controls. We now investigated whether visible and near infrared spectroscopy were also useful for exploring properties of homeopathic preparations. Materials and methods Homeopathic preparations of copper sulfate (CuSO4), hypericum and sulfur (S8) were produced in 30 sequential steps of 1:100 dilutions (c-preparations). As controls, succussed potentization medium was used. Transmission of the samples from 190-1100nm was measured 4 times on 5 days with a double beam Shimadzu UV PC 1601 spectrophotometer. To correct for the daily variations of the spectrophotometer, transmission of the samples at each nm was divided by the average transmission of the controls. Median transmissions of the samples were calculated for the ranges of 190-340nm (near and middle UV), 340-640nm (visible light without red), and 640-1100nm (red and near infrared). Differences in the median transmission between potency levels from 6c to 30c were determined using Kruskal-Wallis and Jonckheere-Terpstra tests. Results Differences in transmissions of the various potency levels were more pronounced in the UV range than in the visible or red/near infrared range. The Kruskal-Wallis test revealed significant differences for homeopathic preparations of CuSO4, hypericum and S8 in the UV range (p=0.032, 0.008, 0.009, respectively) and of S8 in the visible range (p=0.026). Jonckheere's test showed a tendency towards ascending medians with ascending potency levels for CuSO4 in the UV range (p=0.080). Significant trends were revealed for hypericum in the visible range (p=0.042, descending medians) and S8 in the UV range (p=0.015, ascending medians). Conclusion UV spectroscopy seemed to be more suitable for investigating homeopathic preparations than visible or near infrared spectroscopy, since differences in transmission were more pronounced in the UV range.

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Yokota, Toshiaki, Susumu Sasaki, Nobuki Kawashima, Masahiro Ota, and Motofumi Usui. "Spectral Observation of Defects in Space Using Polymer Chain Irradiated by Oxygen Ion Beam." Applied Spectroscopy 48, no. 1 (January 1994): 121–26. http://dx.doi.org/10.1366/0003702944027697.

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We discuss some effects of oxygen ions on a polymer, on the basis of spectroscopic data analysis related to the study of the effect of the space medium in the lower earth orbit (LEO). Oxygen and UV light have an influence upon the surface of spacecraft in LEO. The light transmittance of polymers decreases with time during oxygen ion beam irradiation. The signals of CO2and C=O in the ATR spectra indicate that the surface of the polymer is oxidized and the chain of the polyimide partially cut. When the oxygen ion beam hits the aluminum coated on the polymer, the mass loss of aluminum can be clearly detected by measuring the change of the transmittance.

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Rosenzweig, Zeev, and Edward S. Yeung. "Laser-Based Double-Beam Circular Dichroism Detector for Liquid Chromatography." Applied Spectroscopy 47, no. 12 (December 1993): 2017–21. http://dx.doi.org/10.1366/0003702934066442.

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A highly sensitive and selective double-beam laser-based circular dichroism (CD) detector for high-performance liquid chromatography (HPLC) is presented. An all-electronic noise canceller circuit was used to subtract the intensity of the right circularly polarized light from the intensity of the left circularly polarized light. Both of these beams were derived from the same Ar-ion laser operated at 488 nm. The chiral inorganic complexes of tris(ethylenediamine)cobalt(III), Co(en)33+, which are CD active at this wavelength [Δɛ(488 nm) = 1.9 cm2 mol−1], were chosen as test compounds. The two enantiomers were chromatographically separated from the corresponding racemic mixture through the use of potassium antimonyl(III) tartrate hydrate and ion-pair reversed-phase liquid chromatography. A practical noise-to-signal ratio of 4 × 10−6 for CD measurements was achieved despite the presence of the high background absorption, which is 45 times higher than the CD signal for this particular system. The detector is linear through two orders of magnitude (10−3 M-10−5 M). The deviation between consecutive measurements is less than 5% and the noise level is 1.8 × 10−6 AU. A limit of detection (LOD) of 1.2 × 10−6 M at the flow cell, which corresponds to 25 ng injected material, was achieved. This value is similar to the LOD that was obtained for the same species by using laser-based high-frequency modulation and is only 3.5 times worse than thermal-lens CD detection. Being simpler and less expensive than other laser-based systems, our double-beam HPLC-CD detector provides a three-orders-of-magnitude improvement in sensitivity as compared to that for conventional CD spectrometers.

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Davidson, J. A., J. H. Evans, and A. R. Peaker. "Light-beam-induced transient spectroscopy of oxidation-induced stacking faults in silicon." Materials Science and Engineering: B 24, no. 1-3 (May 1994): 167–69. http://dx.doi.org/10.1016/0921-5107(94)90320-4.

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Lekkas, Ioannis, Mark D. Frogley, Timon Achtnich, and Gianfelice Cinque. "Rapidly frequency-tuneable, in-vacuum, and magnetic levitation chopper for fast modulation of infrared light." Review of Scientific Instruments 93, no. 8 (August 1, 2022): 085105. http://dx.doi.org/10.1063/5.0097279.

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We present an in-vacuum mechanical chopper running at high speed and integrated into a magnetic levitating motor for modulating optical beams up to 200 kHz. The compact chopper rotor allows fast acceleration (10 kHz s−1 as standard) for rapid tuning of the modulation frequency, while 1 mm diameter slots provide high optical throughput for larger infrared beams. The modulation performances are assessed using a reference visible laser and the high brightness, broadband, infrared (IR) beam of synchrotron radiation at the MIRIAM beamline B22 at Diamond Light Source, UK. For our application of IR nanospectroscopy, minimizing the temporal jitter on the modulated beam due to chopper manufacturing and control tolerances is essential to limit the noise level in measurements via lock-in detection, while high modulation frequencies are needed to achieve high spatial resolution in photothermal nanospectroscopy. When reaching the maximum chopping frequency of 200 kHz, the jitter was found to be 0.9% peak-to-peak. The described chopper now replaces the standard ball-bearing chopper in our synchrotron-based FTIR photothermal nanospectroscopy system, and we demonstrate improved spectroscopy results on a 200 nm thickness polymer film.

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Tran, Chieu D., Ricardo J. Furlan, and Jian Lu. "Development of a Multiwavelength Thermal Lens Spectrophotometer Based on an Acousto-Optic Tunable Filter as a Polychromator." Applied Spectroscopy 48, no. 1 (January 1994): 101–6. http://dx.doi.org/10.1366/0003702944027679.

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Instrumentation development of a novel multiwavelength thermal lens spectrophotometer which has the capability of achieving truly multiwavelength excitation is described. The spectrophotometer is based on a new concept by which the sample is excited by multiwavelength excitation beams simultaneously, not sequentially as in previously reported multiwavelength thermal lens apparatus. This was accomplished by use of the acousto-optic tunable filter (AOTF) as a polychromator. Specifically, four different rf signals were simultaneously applied to the filter to enable it to diffract incident multiline laser light into a beam which contained four different wavelengths. This multiwavelength beam was then used to excite the sample, and the corresponding thermal lens signal was measured by a He-Ne probe laser. Compared with other multiwavelength thermal lens instruments, this all-solid-state thermal lens spectrophotometer has advantages that include its ability to simultaneously analyze multicomponent samples in microsecond times scale, without the need for any prior sample preparation. With this apparatus and with the use of a 12-mW multiwavelength excitation beam, the limit of detection for four-component (lanthanide ions) samples is estimated to be 10−6 cm−1, which is similar to the detection limit obtained for one-component samples with the use of a single-wavelength system.

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32

Xi, Xiaobing, and Edward S. Yeung. "Axial-Beam Absorption Detection for Capillary Electrophoresis with a Conventional Light Source." Applied Spectroscopy 45, no. 7 (August 1991): 1199–203. http://dx.doi.org/10.1366/0003702914335931.

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33

Galynskii, M. V., and F. I. Fedorov. "Transformation of the beam tensor during a light-medium interaction." Journal of Applied Spectroscopy 44, no. 2 (February 1986): 200–203. http://dx.doi.org/10.1007/bf00660366.

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Romanov, O. G., and A. L. Tolstik. "Transformation of singular light beam transverse structure in resonant media." Journal of Applied Spectroscopy 75, no. 4 (July 2008): 532–38. http://dx.doi.org/10.1007/s10812-008-9080-z.

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35

Adel, M., R. Kalish, and V. Richter. "Light-ion-beam-induced annealing of implantation damage in diamond." Journal of Materials Research 1, no. 3 (June 1986): 503–9. http://dx.doi.org/10.1557/jmr.1986.0503.

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The removal of defects in diamond by light-ion bombardment has been studied by means of Rutherford backscattering spectroscopy (RBS) channeling techniques. The damage produced by 1 × 1014 Sb ions cm−2 at 300 keV (below the critical dose for graphitization) was observed to diminish by as much as 50% under bombardment with H and He ions. The ion-beam-induced annealing has been studied as a function of ion dose and incident angle (channeling and random). Although the data sets differ markedly, they nearly coincide when the dose is normalized to the energy deposited by elastic collisions in the damaged region. This may indicate that nuclear and not electronic collisions contribute primarily to the in situ annealing in a reasonably good insulator such as diamond.

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36

Wang, Shuchao, Ali K. Yetisen, Kun Wang, Martin Jakobi, and Alexander W. Koch. "Dependence of the Michelson Interferometer-Based Membrane-Less Optical Microphone–Photoacoustic Spectroscopy Gas-Sensing Method on the Fundamental Parameters of a Photoacoustic Gas Cell." Photonics 10, no. 8 (August 1, 2023): 888. http://dx.doi.org/10.3390/photonics10080888.

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This article presents a mathematical model of the Michelson interferometer (MI)-based membrane-less optical microphone (MeoM)–photoacoustic spectroscopy (MeoM–PAS) method, which is also referred to as MI-based photoacoustic interferometry (PAI), for gas-sensing applications in complex and adverse environments, as it offers a completely static measurement system and the separation of a photoacoustic (PA) gas cell from the measuring system. It also investigates the dependence of this method on the fundamental parameters of a cubical PA gas cell using axial PA signals. The results indicate that the phase of the method is a sine function of the distance between the two light beams and a power exponent of the cell length, the cell height, and the distance between the excitation source and the nearest light beam, under the condition that the PA gas cell is resonant and that the excitation source is at the position of the peak or valley of the PA signals. It is at its maximum when the distance between the two light beams is approximately half the wavelength of the PA signals under the same conditions. In addition, the dependence of a PA gas cell using non-axial PA signals is described under the conditions that the PA gas cell is resonant, which is consistent with the changing aforementioned parameters for the distance between the two light beams, the cell length and height, and the distance between the excitation source and the nearest light beam. Furthermore, the selection of five common materials (aluminum, brass, glass, quartz, and stainless steel) for the PA gas cell is discussed under the influence of temperature fluctuations outside the PA gas cell, noise inside and outside the PA gas cell, as well as thermal and viscous losses inside the PA gas cell. The results indicate that quartz and stainless steel are promising options. Finally, the parameters related to the sensitivity enhancement of the method are analyzed using mathematical models, where the sensitivity of the method can be theoretically enhanced by reducing the dimensions of the PA gas cell.

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Balerna, Antonella. "DAFNE-Light DXR1 Soft X-Ray Synchrotron Radiation Beamline: Characteristics and XAFS Applications." Condensed Matter 4, no. 1 (January 8, 2019): 7. http://dx.doi.org/10.3390/condmat4010007.

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X-ray Absorption Fine Structure Spectroscopy (XAFS) is a powerful technique to investigate the local atomic geometry and the chemical state of atoms in different types of materials, especially if lacking a long-range order, such as nanomaterials, liquids, amorphous and highly disordered systems, and polymers containing metallic atoms. The INFN-LNF DAΦNE-Light DXR1 beam line is mainly dedicated to soft X-ray absorption spectroscopy; it collects the radiation of a wiggler insertion device and covers the energy range from 0.9 to 3.0 keV or the range going from the K-edge of Na through to the K-edge of Cl. The characteristics of the beamline are reported here together with the XAFS spectra of reference compounds, in order to show some of the information achievable with this X-ray spectroscopy. Additionally, some examples of XAFS spectroscopy applications are also reported.

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Reddy, Pulagam Sai Kumar, Darapu Mahesh, C. Uday Teja, Muthuluri Janaki, and Kiran Mannem. "Non-Invasive Glucose Monitoring Using NIR Spectroscopy." Journal of Physics: Conference Series 2325, no. 1 (August 1, 2022): 012021. http://dx.doi.org/10.1088/1742-6596/2325/1/012021.

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Abstract Diabetes Mellitus (DM), a metabolic condition, can lead to major health problems if it is not adequately treated. Traditional blood glucose monitors are intrusive and give people pain and irritation. As a result, the study’s goal was to find a non-invasive way to measure blood glucose. To determine blood glucose parameters, this system uses an NIR Spectroscopy-based system with a light source of wavelength 950nm. The light source illuminates the skin of the wrist, and a photodiode receiver captures the reflected beam. An Arduino UNO microcontroller receives the conditioned signal and digitalizes it. The spectrum is calculated by the Arduino board based on the subject’s blood glucose levels. Pre-processing and segmenting the raw waveforms are required to obtain the peaks of the NIR spectrum and to compute the regression model.

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Schmidt, Werner. "A Novel, Rapid Scan Spectrophotometer for near Infrared Spectroscopy." Journal of Near Infrared Spectroscopy 6, A (January 1998): A159—A162. http://dx.doi.org/10.1255/jnirs.187.

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An innovative rapid scan monochromator so far routinely utilized in the visible wavelength range has been shown to be adaptable to the near infrared spectral region, as well. The number of optical and mechanical components is reduced to a minimum resulting in excellent light-throughput, a low stray-light level, low cost, compactness and rigidity. The spectrometer has been designed to allow all kinds of spectral measurements such as absorption, transmission, fluorescence and reflection in a single beam mode. A computer-program allowing data acquisition, control and calibration functions as well as real time averaging and life display of spectra on the computer screen has been developed.

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40

Tsuchikawa, Satoru, and Shigeaki Tsutsumi. "Analytical Characterization of Reflected and Transmitted Light from Cellular Structural Material for the Parallel Beam of NIR Incident Light." Applied Spectroscopy 53, no. 9 (September 1999): 1033–39. http://dx.doi.org/10.1366/0003702991948026.

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41

Ozawa, Kenichi, Yoshihiro Aiura, Daisuke Wakabayashi, Hirokazu Tanaka, Takashi Kikuchi, Akio Toyoshima, and Kazuhiko Mase. "Beamline commissioning for microscopic measurements with ultraviolet and soft X-ray beam at the upgraded beamline BL-13B of the Photon Factory." Journal of Synchrotron Radiation 29, no. 2 (February 16, 2022): 400–408. http://dx.doi.org/10.1107/s160057752200090x.

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Beamline 13 of the Photon Factory has been in operation since 2010 as a vacuum ultraviolet and soft X-ray undulator beamline for X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), and angle-resolved photoelectron spectroscopy (ARPES) experiments. The beamline and the end-station at branch B have been recently upgraded, enabling microscopic XPS, XAS, and ARPES measurements to be performed. In 2015, a planar undulator insertion device was replaced with an APPLE-II (advanced planar polarized light emitter II) undulator. This replacement allows use of linear, circular, and elliptical polarized light between 48 and 2000 eV with photon intensities of 109–1013 photons s−1. For microscopic measurements, a toroidal post-mirror was renewed to have more focused beam with profile sizes of 78 µm (horizontal) × 15 µm (vertical) and 84 µm × 11 µm at photon energies of 100 and 400 eV, respectively. A high-precision sample manipulator composed of an XYZ translator, a rotary feedthrough, and a newly developed goniometer, which is essential for microscopic measurements, has been used to control a sample specimen in six degrees of freedom, i.e. translation in the X, Y, and Z directions and rotation in the polar, azimuthal, and tilt directions. To demonstrate the performance of the focused beams, one- and two-dimensional XPS and XAS scan measurements of a copper grid have been performed. It was indicated from analysis of XPS and XAS intensity maps that the actual spatial resolution can be determined by the beam size.

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42

Kryzhkov, D. I. "Light-Emitting Si:Er Structures Produced by Molecular-Beam Epitaxy: High-Resolution Photoluminescence Spectroscopy." Semiconductors 39, no. 12 (2005): 1399. http://dx.doi.org/10.1134/1.2140312.

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43

Power, J. F., and S. W. Fu. "Dual Beam Light Profile Microscopy: A New Technique for Optical Absorption Depth Profilometry." Applied Spectroscopy 58, no. 2 (February 2004): 166–78. http://dx.doi.org/10.1366/000370204322842896.

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44

Druetta, M., T. Bouchama, S. Martin, and J. Désesquelles. "VUV Spectroscopy of Ar9+ and Kr9+ Low Energy Collision with H2." International Astronomical Union Colloquium 102 (1988): 365–68. http://dx.doi.org/10.1017/s0252921100108103.

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Photon spectroscopy of low energy collisions between multicharged ions and neutrals has opened new possibilities of wavelength and energy level determination since recent multicharged ion sources like the E.C.R. source, giving μA electric current of highly multicharged ions, are available.The experimental set-up has been already described (1.2) The ion beam is produced by an E.C.R. ion source. Light emitted as a result of the collision is observed at 25* to the beam axis with a 3m grazing incidence (82*) spectrometer equipped with a 300 or 600 lines/mm grating blazed at 55.2 or 27.6 nm respectively. The detection is realised by micro-channel plates (MCP). Typical beam currents are 0.45 and 0.40 μA for Kr9+and Ar9+respectively, through the 8 mm diameter entrance hole of the gas cell. The gas pressure was kept at 5 × 10−5mbar. The emission cross sections of all the new observed lines have been mesured. Taking into account the statistics; the error on the beam intensity due to double collisions; the errors on the pressure, on the relative efficiency curve of the spectrometer and on the absolute calibration; we may estimate the error bar to ± 30%.

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45

Klysubun, Wantana, Pinit Kidkhunthod, Pongjakr Tarawarakarn, Panidtha Sombunchoo, Chanapa Kongmark, Sukit Limpijumnong, Saroj Rujirawat, Rattikorn Yimnirun, Gamolwan Tumcharern, and Kajornsak Faungnawakij. "SUT-NANOTEC-SLRI beamline for X-ray absorption spectroscopy." Journal of Synchrotron Radiation 24, no. 3 (April 4, 2017): 707–16. http://dx.doi.org/10.1107/s1600577517004830.

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The SUT-NANOTEC-SLRI beamline was constructed in 2012 as the flagship of the SUT-NANOTEC-SLRI Joint Research Facility for Synchrotron Utilization, co-established by Suranaree University of Technology (SUT), National Nanotechnology Center (NANOTEC) and Synchrotron Light Research Institute (SLRI). It is an intermediate-energy X-ray absorption spectroscopy (XAS) beamline at SLRI. The beamline delivers an unfocused monochromatic X-ray beam of tunable photon energy (1.25–10 keV). The maximum normal incident beam size is 13 mm (width) × 1 mm (height) with a photon flux of 3 × 108to 2 × 1010 photons s−1(100 mA)−1varying across photon energies. Details of the beamline and XAS instrumentation are described. To demonstrate the beamline performance,K-edge XANES spectra of MgO, Al2O3, S8, FeS, FeSO4, Cu, Cu2O and CuO, and EXAFS spectra of Cu and CuO are presented.

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46

Renn, Curtiss N., and Robert E. Synovec. "Pointing-Stability-Limited Dual-Beam Absorbance Measurements by Position-Sensitive Detection." Applied Spectroscopy 43, no. 8 (November 1989): 1393–98. http://dx.doi.org/10.1366/0003702894204380.

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A HeCd laser was examined as a light source for dual-beam absorbance neasurements by position-sensitive detection. The measurement was limited by the laser point stability and, also, unspecified laser radiation that was effectively reduced by a spatial and spectral filter combination. An absorbance detection limit of 5 × 10−4 AU (3 × rms baseline noise) was predicted from an experimental optimization procedure. The detection limit was supported by microbore high-performance liquid chronatography of a B-2 vitamin sample, detecting riboflavin absorbance at 325 nm. Issues regarding the improvement of dual-beam absorbance measurements by position-sensitive detection are addressed.

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47

Watanabe, Takeshi, Yoshinori Iketaki, Takashige Omatsu, Kimihisa Yamamoto, and Masaaki Fujii. "Two-Point Separation in Far-Field Super-Resolution Fluorescence Microscopy Based on Two-Color Fluorescence Dip Spectroscopy, Part I: Experimental Evaluation." Applied Spectroscopy 59, no. 7 (July 2005): 868–72. http://dx.doi.org/10.1366/0003702054411562.

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The two-point resolution of a novel two-color far-field super-resolution fluorescence microscopy was evaluated by measuring fluorescent beads 100 nm in diameter. This microscopy is based on a combination of two-color fluorescence dip spectroscopy and a phase-modulation technique for a laser beam. By simply introducing two-color laser light, the size of the fluorescent image of a bead was shrunk down to a diameter of 250 nm from the diffraction-limited image with a diameter of 360 nm. For two closely adjacent fluorescent beads with a separation distance of 350 nm, the two-color microscope clearly gave separated fluorescence images, while the conventional one-color fluorescence microscope could not resolve them. It has been proved that our technique breaks Rayleigh's diffraction limit.

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48

Rein, Alan J. "A New Capability for Light Microscopes: Mid infrared Molecular Analysis." Microscopy Today 11, no. 4 (August 2003): 16–21. http://dx.doi.org/10.1017/s1551929500053013.

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The merger of molecular spectroscopy with microscopy is certainly not a new concept. Microscope attachments for FT-IR spectrometers have been available for nearly two decades and there are literally thousands of FT-IR spectrometers with these devices currently installed. The vast majority of them are applied to contaminant or forensic oriented problems. As such, the microscopes are often used as sophisticated beam condensers, enabling the spectrometer to focus infrared radiation on the samples that are typically larger than 10 microns.

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49

Gardiner, Derek J., and Michael Bowden. "Raman mapping and imaging using microline focus spectromety (MiFS)." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 2 (August 1992): 1510–11. http://dx.doi.org/10.1017/s0424820100132182.

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Early attempts to obtain Raman images relied upon illuminating the whole field of view with laser light, wavelength selecting the scattered light and imaging it onto a vidicon type TV detector. This method had several limitations, principally with sensitivity and inability to deal with fluorescence interference. Improvements have been made to this general approach, by the use of interference filters to select the required portion of the Raman spectrum for specific images and the possibilities of using Hadamard transform spectroscopy to produce micro-Raman images have been explored. Alternatively, the advantages of the single point micro Raman instrument can be retained and the sample moved under the focussed beam, either manually or by computer control, and the resulting spectroscopic data processed to generate the required map, image or profile.The development of cooled, slow scan, charge coupled device (ccd) detectors offers the possibility of using a line focus arrangement to reduce greatly the data collection times. Raman Microline Focus Spectroscopy (MiFS) utilises a line focussed Raman microscope coupled to a non-astigmatic spectrograph operating with a slow scanned ccd detector.

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Oura, M., T. M. Kojima, Y. Awaya, Y. Itoh, K. Kawatsura, M. Kimura, T. Koizumi, T. Sekioka, H. Yamaoka, and M. Cox. "Experimental apparatus for the study of photoabsorption processes of multiply charged ions by synchrotron radiation." Journal of Synchrotron Radiation 5, no. 3 (May 1, 1998): 1058–60. http://dx.doi.org/10.1107/s0909049597015379.

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Photon–ion merged-beam apparatus using a compact ECR ion source and a high-brilliance light source has been designed for the study of photoabsorption processes of multiply charged ions. Photoion spectroscopy will be performed along isoelectronic, isonuclear and isoionic sequences. The main features of this apparatus are described.

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Journal articles on the topic 'Light beam spectroscopy'

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