X-ray Physics

After passage through matter, the energy spectrum of a polychromatic beam of x-rays contains valuable information about the elemental composition of the absorber. Conventional x-ray systems or x-ray computed tomography (CT) systems, equipped with scintillator detectors operated in the integrating mode, are largely insensitive to this type of spectral information, since the detector output is proportional to the energy fluence integrated over the whole spectrum. The main purpose of this paper is to investigate to which extent energysensitive photon counting devices, operated in the pulse-mode, are capable of revealing quantitative information about the elemental composition of the absorber. We focus on the detection of element-specific, K-edge discontinuities of the photo-electric cross-section. To be specific, we address the question of measuring and imaging the local density of a gadolinium-based contrast agent, in the framework of a generalized dual-energy pre-processing. Our results are very promising and seem to open up new possibilities for the imaging of the distribution of elements with a high atomic number Z in the human body using x-ray attenuation measurements. To demonstrate the usefulness of the detection and the appropriate processing of the spectral information, we present simulated images of an artherosclerotic coronary vessel filled with gadolinium-based contrast agent. While conventional systems, equipped with integrating detectors, often fail to differentiate between contrast filled lumen and artherosclerotic plaque, the use of an energy-selective detection system based on the counting of individual photons reveals a strong contrast between plaque and contrast agent.

The scientific objective of the X-ray Advanced Concepts Testbed (XACT) is to measure the X-ray polarization properties of the Crab Nebula, the Crab pulsar, and the accreting binary Her X-1. Polarimetry is a powerful tool for astrophysical investigation that has yet to be exploited in the X-ray band, where it promises unique insights into neutron stars, black holes, and other extreme-physics environments. With powerful new enabling technologies, XACT will demonstrate X-ray polarimetry as a practical and flight-ready astronomical technique. Additional technologies that XACT will bring to flight readiness will also provide new X-ray optics and calibration capabilities for NASA missions that pursue space-based X-ray spectroscopy, timing, and photometry.

A superluminal quantum-vortex model of the electron and the positron is produced from a superluminal double-helix model of the photon during electron-positron pair production. The two oppositely-charged (with Q = ±e sqrt (2/α) = 16.6e) open-helix spin-½ half-photons compose the double-helix photon. These half-photons separate and curl up their separated superluminal single-helical trajectories to form an electrically-charged superluminal closed-helix spin-½ quantum-vortex electron model and a corresponding positron model. The helical radius and the Dirac equation's zitterbewegung angular frequency of the quantum vortex electron and positron models equal the helical radius and zitterbewegung angular frequency of the two spin-½ half-photons, each of energy E = mc^2 , that composed the double-helix photon model of energy E = 2mc^2 from which the electron and positron models were produced. The photon and electron models are also compatible when a photon of energy E > 2mc^2 produces a relativistic electron-positron pair. Implications of the quantum vortex electron model for electron stability are discussed.

The Voynich manuscript is the book dated as fifteen century, written using specific and smart coding methods. This article describes the methods how it was analyzed and how coding keys were found. The last manuscript page decoding. Correlation of the last page content with John Dee notes. The proof that the Voynich manuscript and the "Book of Dunstan" - the same manuscripts. This article contains Engish (pages 1-81) and equal Russian (pages 82 - 170) versions.

X-ray is being used widely in medical and in other fields of science, engineering, and technology since its invention in the year 1895. Globally, the growing number of general population and the high prevalence of various critical diseases are augmenting the need for X-ray imaging equipment for an accurate diagnosis. Although X-ray tube technology (Coolidge tube) is about 106 years old, it has been still used widely today for medical diagnostic imaging. Various types of X-ray tubes are classified. The indicative list for the standards pertaining to performance and safety of medical electrical equipment and diagnostic X-ray tube assembly includes the following: IEC 60601-1-2/IS 13450-1-2, IEC 60601-
1-3/IS 13450-1-3, IEC 60601-1-6, IEC 60601-1-8, IEC 60601-1-9, IEC 60601-2-28, IEC 60601-2-54, IEC 60522, IEC 60806, IEC 60336, IEC 61267, IEC 61674, IEC 61676, IEC 60613, IEC 60526, IEC 62304, IEC 62366, ISO 13485, ISO 14000, ISO 14971, and ISO 10993-1. The manufacturing processes of the X-ray tube assembly are listed as follows: (step 1) X-ray tube insert parts processing and cleaning; (step 2) X-ray tube insert parts (anode and cathode) assembly processing; (step 3) glass or metal-ceramic envelope processing; (step 4) degassing of X-ray tube insert; (step 5) seasoning of X-ray tube insert; (step 6) X-ray tube assembly processing; (step 7) final testing of X-ray tube assembly; and (step 8) quality control of X-ray tube assembly. As per the recommendations of Atomic Energy Regulatory Board (AERB), Government of India, the accuracy of the applied X-ray tube potential of the general radiography and fluoroscopy, computed tomography, mammography, and dental X-ray machine should be within +/-5, +/-2, +/-1, and +/-5, respectively, of the corresponding measured values.
Linearity of the X-ray tube current (mA or mAs) loading stations (coefficient of linearity (CoL)) of the general radiography and fluoroscopy, computed tomography, mammography, and dental X-ray machine should be within <0.1, +/-0.1, +/-0.1, and <0.1, respectively. The most common causes for the X-ray tube failures include the following: (i) cathode filament burnout, (ii) target micro-cracking, (iii) tube arcing, (iv) slow leaks in the tube, and (v) bearings of rotating anode. Globally, more than 20,000 patents have been filed so far on the innovations of X-ray tube technology

Raja Ramanna Centre For Advanced Technology, Indore,(M.P) 2 | P a g e DECLARATION I, Divya Aggarwal student of M.Sc. hereby declare that the Major Project dissertation titled "Frequency Analysis Of X-Ray reflectivity data by FFT" Which is submitted by me A4450014016 3 | P a g e CERTIFICATE On the basis of declaration submitted by Divya Aggarwal, student of M.Sc (Applied Physics)., I hereby certify that the Dissertation titled "Frequency Analysis Of X-Ray reflectivity data by FFT" which is submitted to Department of, Amity Institute of Applied Sciences, Amity University, Uttar Pradesh, Noida, in partial fulfillment of requirement for the award of the degree of M.Sc (Applied Physics)., is an original contribution with existing knowledge and faithful record of work carried out by her under my guidance and supervision.

Pesawat Radiologi Sinar-X lazim disebut Pesawat Röntgen. Pesawat Röntgen adalah pesawat medik yang dapat menghasilkan sinar-X/sinar Röntgen baik untuk keperluan diagnostik maupun terapi. Pesawat ini bekerjanya sangat ditentukan oleh adanya pasokan listrik dari PLN. Jika PLN padam, artinya aliran listrik mati maka Pesawat Röntgen tidak bisa memproduksi sinar-X.
Ditinjau dari teknologi dan cara kerjanya, Pesawat Röntgen  dibagi menjadi 4 jenis yaitu: 1) Pesawat Röntgen Konvensional/Pesawat Röntgen Dasar; 2) Pesawat Röntgen Kondensator Discharge; 3) Pesawat Röntgen Frekuensi Tinggi; dan 4) Pesawat Röntgen Kondensator Discharge Berdaya Baterai.
Sedangkan ditinjau dari segi fisik pesawat ini dibedakan menjadi Pertama Pesawat Röntgen Mobil yaitu pesawat Röntgen yang bisa dibawa ke mana-mana sehingga bisa melayani pasien yang berada diruang perawatan dan Kedua Pesawat Röntgen Stasioner, yaitu Pesawat Röntgen yang dipasang menetap  di ruang Unit Pelayanan Radiologi. 
Khusus untuk pesawat Röntgen kondensator Discharge Berdaya Baterai, tegangan listrik bolak-balik dari PLN digunakan untuk mengisi baterai. Selanjutnya tegangan DC dari baterai berfungsi sebagai energi pembangkit sinar-X.

Tutankhamun's golden mask and throne were investigated by an improved XRDF setup, which was specially designed for this study. XRD pattern and XRF data were taken non-destructively from one small site (2mmtD) in air under contact free condition.
Golden sheets forming the golden mask were confirmed tobe23 K, and the surface of the sheet, used for shaping its face, was coated with a very thin layer of 18 K (28 nm) white gold. The mask and throne were decorated with artificial glass,v materials in many shades of blue, and with precious stones such as obsidian, magnesite, carnelian, lapis lazuli, amazonite and alabaster.
Eighteen K gold alloy and dark blue glass were prepared successfullv for reproducing two individual colors on the golden mask, i.e. white gold on the face, and dark blue on the Nemes (headdress).

The Search for Extra-Terrestrial Intelligence (SETI) has so far been unsuccessful and demands additional methods. To achieve this, we introduce a two-dimensional metric for civilizational development, using the Kardashev scale of energy use and the Barrow scale of inward manipulation. We advance energetic, societal, scientific, computational, and philosophical arguments that black holes are attractors for intelligence. An application of the two-dimensional metric leads to a simple, consistent and observable hypothesis to test the existence of very advanced civilizations. We suggest that some already observed X-Ray Binaries may be unnoticed advanced civilizations, scoring high on both the Kardashev and Barrow scales. The appendix provides an argumentative map of the paper's main thesis.

Keywords: SETI, black holes, Kardashev scale, Barrow scale, star lifting, XRB

Correction: This statement "Freeman Dyson proposed in his landmark (1979) paper that a civilization could [...] exploit the time dilation effects generated by black holes to survive forever" is wrong, his argument had not to do with dilation effects.

More info: Vidal, C. 2011 Black Holes: Attractors for Intelligence? Kavli Royal Society International Centre, "Towards a scientific and societal agenda on extra-terrestrial life", 4-5 Oct 2010.http://arxiv.org/abs/1104.4362 http://student.vub.ac.be/~clvidal/writings/Vidal-Black-Holes-Intelligence.pdf

More fascinating open questions at: http://evodevouniverse.com/wiki/Research_on_SETI,_black_holes,_XRB_and_star_lifting

News report at: http://news.discovery.com/space/super-civilizations-might-live-off-black-holes-110430.html

Este trabalho teve como objetivo constatar a eficácia do programa de garantia da qualidade dos serviços de radiologia em dois estabelecimentos assistenciais de saúde (EAS) pertencentes à esfera administrativa municipal do município de Caldas Novas – GO, por meio de auditorias da qualidade. Foram inspecionadas exigências da Portaria Federal SVS/MS nº 453 de 1998, que estabelece as diretrizes básicas de proteção radiológica em radiodiagnóstico médico e odontológico. As informações foram coletadas por entrevistas com funcionários, análise critica de documentos, observações das atividades do ambiente e de condições de trabalho circunvizinho, onde se investigou os seguintes aspectos: formação profissional, jornada de trabalho, documentação dos serviços, estrutura física do serviço como um todo, salas para exames radiográficos, equipamentos de proteção individual, equipamentos de raios-x, câmaras escuras, salas de laudos, procedimentos com pacientes, procedimentos com filmes e revelação e protocolos dos serviços. As evidencias obtidas indicaram a ocorrência de elevado número de não conformidades dos itens auditados em ambos os serviços de radiodiagnóstico dos EAS, especialmente o descumprimento de alguns protocolos de segurança. A não realização de manutenções preventivas nos equipamentos e a falta de investimentos em treinamentos de atualização profissional foram às principais causas das não conformidades evidenciadas. As ações corretivas devem ser implementadas e monitoradas para que os setores de radiologia prestem um serviço de qualidade para a população.

Abetract—The scattering of X-rays and v-rays are events that have strong dependencies on the polarization ofthe incident and scattered photons. Because of this, scattering problems that can be solved without explicit reference to the state of polarization of the incident and scattered radiation are exceptional. This article reviews available information on polarizationeffects arising when photons in the X-ray and v-ray regime undergo photoelectric effect, coherent (Rayleigh) scattering and incoherent (Compton) scattering by atomic electrons. In addition to descriptions and discussion of these effects, we study the backscattering of y-rays from an infinite thickness target excited with a plane slant monodirec-tional and monochromatic source, using the Boltzmann transport theory and the mathematical representation ofpolarization introduced by Stokes. Results from this model, for both unpolarized and polarized y-ray sources, are compared with computations performed neglecting or averaging polarization effects, showing the limitations of such approximations.

Fisika klasik adalah ilmu fisika yang berkembang pada abad ke 17 – 18 dan diprakarsai oleh Sir Issac Newton dikarenakan kesuksesannya didalam merumuskan tiga hukum dasar mengenai gerak. Pada era abad ke 19, ada sebuah fenomena baru dimana fisika klasik tersebut tidak mampu menjelaskan. Fenomena baru tersebut adalah fenomena radiasi benda hitam. Untuk mampu menjelaskannya, maka para Fisikawan mulai menggagas teori – teori baru yaitu teori Fisika Modern. Didalam Fisika Modern, kajian radiasi benda hitam dibahas terlebih dahulu. Dimana pembahasanya dimulai dari stefan – boltzmann. Menurut Stefan – boltzmann intensitas radiasi benda hitam sempurna adalah sebanding dengan pangkat empat suhu mutlaknya, akan tetapi saat dikaji secara eksperimental benda hitam tidak ada yang sempurna, jadi suatu benda yang menerima kalor belum tentu memancarkan seluruh kalor yang didapatkannya. Oleh karena itu didalam intensitas radiasi benda hitam oleh stefan – boltzmann diperkenalkan sebuah koefisien yang disebut emisivitas yang memiliki makna fisis yaitu berapakah kali dari  benda hitam ideal kah kalor yang dipancarkan oleh benda hitam didalam dunia nyata dan koefisien emisivitas ini akan selalu berbeda untuk tiap material.

Studies on radiative transfer lead to a clean formulation of polarised photon transport in terms of the vector Boltzmann equation whose solution gives the four Stokes components of the ¯ux, from which the full polarisation state of the photons can be determined at any given position, wavelength (energy) and solid angle. One of the relevant results observed during the formulation of the vector transport equation is the partial coverage of the wave properties of the photons with this model. In fact, even if the Boltzmann vector equation is an important step forward for the description of radiative transfer with respect to the scalar approach used to describè`particle''-like photons, it is still insucient to provide a whole description of an important phase-related property like coherence. In this sense, the above vector equation seems to be appropriate for describing photon beams which add incoherently among them, but not for describing coherent interference. Up to now, coherence has been described independently to the transport equation, as an additive term to the vector solution valid for di€use incoherent radiation. New approaches are being investigated in order to include the concept of coherence into the vector transport equation. In this article, a summary view of the evolution of the Boltzmann transport equation will be provided, ®rst from scalar to vector, to take care of the description of the evolution of the polarization state. Secondly the present state of the treatment of coherence will be considered. Finally, the state-of-the-art description of multiple scattering involving Rayleigh scattering will be discussed, in the framework of both re¯ection and transmission experiments. #

Berkembangnya ilmu pengetahuan dan teknologi, menuntut penggunaan suatu materialsecara tapt dan pasti.untuk dapat menggunakan material yang akan digunakan dengan tepat, maka harus dikenali dengan baik dari segi sifat – sifat material yang akan dipilih untuk dipergunakan sesuai kebutuhan. Sifat – sifat ini tentunya sangat beragam macamnya, karena sifat – sifat tersebut dalam penentuannya dapat ditinjau dari berbagai idang keilmuan. Proses pemilihan mateial ini sangat mempertimbangkan sifat tahan korosi, karena hal ini salah satu hal yang sangat penting. Korosi merupakan masalah yang sangat penting dan masalah yang sangat serius dalam dunia material, karena apabila tidak diperhatikan, akan menimbulkan beberapa kerugian – kerugian yang lebih besar, antara lain, : robohnya suatu kontruksi, menimbulkan kebocoran, meledaknya suatu pipa bertekanan, mengaikbatkan berkurangnya kekuatan dan bisa menyebabkan suatu pencemaran pada suatu produk.erkaitan dengan hal tersebut,maka dalam menentukan laju suatu material diperlukan suatu cara. Sehingga daya tahan terhadap korosi pada suatu material dapat diketahui.

Deciphering the internal structure of prehistoric artefacts can provide spectacular insights that might help us understand the people who made them. In order to preserve the integrity of these relics of past civilisations, it is desirable to make such investigations using non-destructive techniques. Recent decades have witnessed a growth in the X-ray computed tomography (CT) applications in the study of cultural heritage objects. This paper presents and discusses tomographic investigations of two Cucuteni ceramic statuettes discovered in Romania. The study was made with a CT device specially designed for archaeometric applications.

The structure adopted by lead sulfide nanoparticles changes surprisingly often as they assemble to form ordered superlattices. [37] Researchers have demonstrated a new high-resolution X-ray imaging technique that can capture the motion of rapidly moving objects and quickly changing dynamics. [36] In a new study published Aug. 17 in Nature Communications, Nemsak, Fadley, Schneider and colleagues demonstrate the use of new techniques in X-ray spectroscopy to illuminate the internal structure of manganese-doped gallium arsenide. [35] With the publication of the first experimental measurements performed at the facility, the European X-ray Free-Electron Laser (EuXFEL) has passed another critical milestone since its launch in September 2017. [34] Purdue University researchers are developing a novel biomedical imaging system that combines optical and ultrasound technology to improve diagnosis of life-threatening diseases. [33] Heart scans for patients with chest pains could save thousands of lives in the UK, research suggests. [32] Unnecessary heart procedures can be avoided with a non-invasive test, according to late breaking research presented today at ESC Congress 2018 and published in Journal of the American College of Cardiology. [31] Now, Columbia University researchers report a new way to zoom in at the tiniest scales to track changes within individual cells. [30] One of the main challenges in tissue engineering today is to create a complete network of blood vessels and capillaries throughout an artificial tissue. [29] Scientists from the University of Freiburg have developed materials systems that are composed of biological components and polymer materials and are capable of perceiving and processing information. [28] Nanotechnology may provide an effective treatment for Parkinson's disease, a team of researchers suggests. [27]

Precipitation strengthening is a highly complex phenomenon on the nanoscale, responsible for providing strength in Al-Cu, Al-Mg-Cu, Al-Mg-Zn and Al-Mg-Si alloys. Advances in methodology, especially high-angle annular dark-field transmission electron microscopy and atomistic calculations provide fundamental insights into the mechanisms behind precipitation. We are beginning to understand how solute elements form precipitates from the Al matrix and how structures relate. Examples are Ω, η' and η-phases of Al-Cu and Al-Mg-Zn, where solute organizes in similar supercells in the aluminium lattice. In Al-Mg-Si and Al-Mg-Cu, discovery of 1D Guinier-Preston zone aids understanding of precipitation and growth in the two systems.

Aluminum oxide (Al 2 O 3) is an emerging material in integrated photonics. It exhibits a very broad transparency window from the UV to the mid-IR, very low propagation losses and a high solubility for rare-earth ions leading to optical gain in different spectral ranges. Al 2 O 3 can be deposited by different wafer-level deposition techniques, including atomic layer deposition and reactive magnetron sputtering, being compatible with the monolithic integration onto passive integrated photonics platforms, such as Si 3 N 4 , to which it provides optical amplification and lasing. When deposited at low temperatures, it is also compatible with integration onto CMOS chips. In this review, the state-of-the-art on the deposition, integration and device development in this photonic platform is described.

We report the generation of ultrahigh brightness X-ray pulses using the Fresh Bunch Self-Seeding (FBSS) method in an X-ray Free Electron Laser (XFEL). The FBSS method uses two different electron slices or bunches, one to generate the seed and the other to amplify it after the monochromator. This method circumvents the trade-off between the seed power and electron slice energy spread, which limits the efficiency of regular self-seeded FELs. The experiment, the performance of which is limited by existing hardware, shows FBSS feasibility, generating 5.5 keV photon pulses which are 9 fs long and of 7.3 ×10−5×10−5 bandwidth and 50 GW power. FBSS performance is compared with Self Amplified Spontaneous Emission/self-seeding performance, measuring a brightness increase of twelve/two times, respectively. In an optimized XFEL, FBSS can increase the peak power a hundred times more than state-of-the-art to multi-TW, opening new research areas for nonlinear science and single molecule imaging.

Many studies have been conducted on the environmental impacts of combustion generated aerosols. Due to their complex composition and morphology, their chemical reactivity is not well understood and new developments of analysis methods are needed. We report the first demonstration of in-flight X-ray based characterizations of freshly emitted soot particles, which is of paramount importance for understanding the role of one of the main anthropogenic particulate contributors to global climate change. Soot particles, produced by a burner for several air-to-fuel ratios, were injected through an aerodynamic lens, focusing them to a region where they interacted with synchrotron radiation. X-ray photoelectron spectroscopy and carbon K-edge near-edge X-ray absorption spectroscopy were performed and compared to those obtained for supported samples. A good agreement is found between these samples, although slight oxidation is observed for supported samples. Our experiments demonstrate that NEXAFS characterization of supported samples provides relevant information on soot composition, with limited effects of contamination or ageing under ambient storage conditions. The highly surface sensitive XPS experiments of airborne soot indicate that the oxidation is different at the surface as compared to the bulk probed by NEXAFS. We also report changes in soot's work function obtained at different combustion conditions. The impact of combustion aerosols on the earth's climate is a still poorly understood subject. All recent reports agree that they have a significant radiative contribution to global warming, yet the quantitative estimations contain large uncertainties 1. The interactions of soot aerosols with the environment and most importantly their reactions with atmospheric water are assumed to be controlled by their surface reactivity (oxidation, adsorp-tion of water molecules), which might depend on the initial fuel composition and the combustion conditions. Considerable efforts have been conducted to study the evolution of size, morphology and chemical composition of aerosol soot particles during atmospheric ageing 2–4. Similar investigations have been carried out in order to describe the evolution of soot microstructure 5,6 , morphology or size distribution 7,8 during high temperature oxidation. The characterization of soot is also essential for predicting the behaviour of filtration systems under

In this paper a practical solution to perform spectral analysis of diagnostic X-ray beams is described, based on a miniaturized Compton selection chamber (CSC) using a Si-PIN detector. Results are compared with those obtained with a first prototype of CSC based on nitrogen cooled high purity germanium (HPGe) detector. With this method, the direct X-ray spectrum is Compton scattered inside the CSC, collected by a solid-state detector and reconstructed using a simplified scattering matrix experimentally determined. The results obtained will be compared with a reference standard, represented by direct spectra acquired with an HPGe detector in a laboratory facility, not applicable for on-field measurements.

Polycrystalline diamond detector prototypes suitable for x-ray spectroscopy were realized and tested. Thick diamond specimens, mechanically polished to reduce the surface roughness, were selected for prototypes development. Noble metal contacts were deposited on both faces, whereas multistrip structures were defined by photolithography on the growth face only with the aim of reducing the coupling capacitances and to allow characterization tests either in planar or sandwich configuration. Leakage currents as low as 20 pA at 500 V were measured on a 270µm thick device. The x-ray sensitivity was tested monitoring the photocurrent as a function of the applied voltage under continuous 8.05 keV Cu Kα irradiation. Studies in pulsed mode were also performed by using a commercial miniature xray source. Pulse height distributions were carried out with a system composed of a charge-sensitive preamplifier and a digital pulse processor multi-channel analyzer. Analysis was carried out around Ta Lα and Cu Κα characteristic lines. Realized prototypes were able to resolve such two characteristic lines only 90 eV apart. Energy resolutions better than 3% have been evaluated for one of the prototype at 8.14 keV. Such features address very good energy resolving capabilities and the suitability of polished polycrystalline diamond in x-ray spectroscopy.

This paper introduces the perfect complementary relationship between the 3-4-5 Pythagorean triangle and the 1:2: √5 right-angled triangle. The classical geometric intimacy between these two right triangles not only provides for the ultimate geometric substantiation of Golden Ratio, but it also reveals the fundamental Pi: Phi correlation (π: φ), with an extreme level of precision, and which is firmly based upon the classical geometric principles.

We present the first results on experimentally measured ultrafast X-ray scattering of strongly driven molecular Iodine and analysis of high-order anisotropic components of the scattering signal. We discuss the technical details of retrieving high fidelity high-order anisotropy components from measured scattering data and outline a method to analyze such signals using Legendre decomposition. We describe how anisotropic motions can be extracted from the various Legendre orders using simulated anisotropic scattering signals and Fourier analysis. We implement the method on the measured signal and observe a multitude of dissociation and vibration motions simultaneously arising from various multiphoton transitions occurring in the sample. We use the anisotropic scattering information to disentangle the different processes and assign their dissociation velocities on the Angstrom and femtosecond scales de-novo. Capturing motions in space and time at the atomic scale is fundamental to the understanding of chemical reactions and structural dynamics of molecules of different complexities. Some of the emerging tools that allow such studies are ultrafast scattering modalities, primarily by X-rays and relativistic electrons, that were made feasible in recent years. In these studies, the motions from excited molecules are captured in a pump-probe scheme, where the excitation pump pulse is often an ultra-short linearly polarized optical laser pulse with a duration shorter than the typical timescales of motion of interest, as illustrated in Fig 1. The scattering signal is then usually integrated over angle for improved fidelity and subtracted from the scattering signal of the unexcited system, to allow tracing changes of signal positions and infer structural dynamics 1. This approach was used successfully to demonstrate coherent motions and dynamics in molecules in the gas phase 2,3 , as well as structural changes in molecules in solution after the electronic excitation 4-6. In these experiments, the optical pulse parameters were carefully chosen to ensure that only single-photon absorption is taking place and that the molecular system is photoexcited to a specific electronic state. This is often done by varying the pump intensity in the pump-probe setup and finding conditions where linearity of the excitation, as manifested by the scattering signal is achieved. The motion is inferred by measuring the scattering difference as a function of delay and applying modeling and simulations. Using angle integrated scattering signal is well justified as it captures all types of motions that take place in the photoexcited system. However , angle-dependent signals can be dramatically attenuated if only the isotropic component is being analyzed. In many cases, there is an inherent anisotropy in the scattering signal when a sample is excited by linearly polarized light due to an optically induced dipole moment transition. This interaction creates geometric alignment in the ensemble, and can be used to filter and enhance the specific processes under study, such as in the case of a single-photon absorption process 7-9 , as well as perturbative two-photon excitation 10,11. Higher orders of anisotropy play a significant role in understanding and probing cases where the molecular system is in the presence of multi-photon absorption and strong laser fields, such as dissociation due to bond softening 12 , above-threshold dissoci-ation 13 , quantum coherent control 14 , and light-induced conical intersections 15. In addition, the interaction of ultrashort pulses with molecules with anisotropic polarizability will generate non-adiabatic (or impulsive) alignment 16. The broad bandwidth of an ultrashort pulse creates rotational wavepackets that evolve and rephase at periodic time delays, forming molecular alignment, manifested by high order anisotropy in the sample under field-free conditions. Molecular alignment is often used to probe diverse phenomena in the molecular frame, such as, polyatomic J o u r n a l N a me , [ y e a r ] , [ v o l. ] ,1-9 | 1

Analytical expressions describing double-scattering intensities of the Compton and Rayleigh effects (Compton-Compton, Compton-Rayleigh, Rayleigh-Compton, and Rayleigh-Rayleigh contributions), are deduced in the framework of the transport theory for an infinitely thick sample irradiated with collimat-ed monochromatic radiation. An orders-of-interaction solution of the integro-differential Boltzmann equation for unpolarized photons is used to separate the multiple-order terms. Interaction kernels for coherent and incoherent scattering include atomic form factors describing the effect of the electronic distribution in multielectron atoms. The total attenuation coefficient of the target takes into account, besides the mentioned scattering processes, the photoelectric effect, important in the x-ray regime. First-order Compton and Rayleigh interactions give monochromatic peaks according to the theoretical model that neglects electron motion. In contrast, Compton-Compton, Compton-Rayleigh, and Rayleigh-Compton contribute asymmetric continuous spectra whose wavelength breadths are the DuMond width and 2A, z (A, ~ is the Compton wavelength), respectively. Single-and double-scattering intensities of the Rayleigh and Compton effects are computed for pure and composite materials as a function of the exci-tation energy and the angular orientations of the incident and takeoff beams. Since absorption in the target is considered, computations can be straightforwardly compared with experimental data and with realistic Monte Carlo simulations. The agreement is good for low excitation energies because the second-order term remains dominant in multiple scattering and bremsstrahlung emission is weaker. However, for higher excitation energies the probability of higher orders of multiple scattering increases, and they cannot be neglected. Although analytical calculations are performed up to the second order in this work, a Monte Carlo simulation is used to show the importance of higher orders in light elements.

Even though already in the seventies, right after the invention of the quantum cascade laser (QCL) concept, it was argued that this device could be operated in the THz (far-infrared) range of the electromagnetic spectrum, it was only in 2002 that the first working THz QCL was demonstrated. Soon afterwards, the progress was very rapid; in the space of 2-3 years, operating temperatures were raised, single-mode DFB devices were produced, applications as local oscillators in heterodyne transceivers were implemented, frequency coverage was extended to the whole 1-5 THz region. In the last few years, technological advancement has continued to improve performances: the maximum operating temperature has now reached about 250 K and about 1 W peak output power has been demonstrated. Several beam engineering techniques have been implemented, with the scope of enhancing spectral purity, improving beam quality and achieving vertical emission. In parallel, various approaches have been devised that allow frequency tunability of the emitted light, with the most efficient schemes achieving a tuning range of about 10% of the central emission frequency. Even the generation of frequency combs directly from THz QCLs has been obtained, by employing dispersion compensated waveguides and an intrinsic material non-linearity. This manuscript reviews the physics underlying the operation of THz QCLs, the technology developed to advance laser performances, and highlights the latest most promising progresses in this fascinating area of opto-electronics.

Purpose Cerebrospinal fluid shunt valves are important tools in hydrocephalus treatment. Adjustable valves, sensitive to MRI, are onerous. They need be controlled; in case of re-settings. The vendor give advices for the radiographic procedure; however, hospitals use variations. The purpose was to investigate the different variations. Method Eight images consisting combinations of protocol features, were subjectively and anonymous rated for image quality. The panel consisted of 60 professionals; 50 radiographers and 10 radiologists, from two hospitals doing neurosurgery services. Signal-to-noise ratio compared the level of desired signal to the level of background noise. Results 348 scores were distributed onto all eight images, revealing the image quality difference was within acceptance. Options as valve on the head side near to the detector versus far to; differing geometry, use of head bowl versus not use, air-gap versus grids, were favored by both professional groups and at both hospitals in a clear priority image, given 2.5 times scores over average (108/43). Noise, revealed being the strongest indicator for priority of the best image for shunt evaluation. Conclusions It is a potential to improve image optimization in shunt radiography.

The enhancement of XRF intensity due to Rayleigh and Compton scattering in the target (which may occur after or before the photoelectric interaction) is commonly neglected in XRF spectrometry. However, this contribution can modify the XRF intensities to an appreciable extent, becoming a source of uncertainty for the computational methods of quantitative analysis. Analytical expressions are presented to describe the intensities of the corresponding four double interactions (which mix the photoelectric effect with the dominant types of scattering) that enhance the XRF intensity: Rayleigh-photoelectric, Compton-photoelectric, photoelectric-Rayleigh and photoelectric-Compton. These relationships are obtained by using an iterative solution of the Boltzmann transport equation for photons, suitable for the study of multiple scattering processes. It is shown that the first three chains contribute with discrete enhancements of the same energy of the XRF line. The last, in contrast, contributes with a short-range continuous spectrum that overlaps the low-energy tail of the peaks. This contribution can modify the line shape in a non-symmetric way, making the unfolding of peaks from energy-dispersive spectra more imprecise.
The corrective terms to the XRF intensity are computed for both pure and composite materials. A common property to all of them is their azimuthal symmetry, a consequence of the isotropic behaviour of the photoelectric effect. As a rule, the chains with Rayleigh scattering predominate in the low-energy regime and contribute between 1 and 10% of the primary XRF line. The chains with Compton scattering prevail at higher energy and their extent may exceed several tens percent. All the corrections show a broad range of variation depending on the incident energy, the composition of the target, which defines its attenuation properties for all the energies, and the incidence and take-off angles.

We present the results of the uniform analysis of 46 XMM-Newton observations of six BAL and seven mini-BAL QSOs belonging to the Palomar-Green Quasar catalogue. Moderate-quality X-ray spectroscopy was performed with the EPIC-pn, and allowed to characterise the general source spectral shape to be complex, significantly deviating from a power law emission. A simple power law analysis in different energy bands strongly suggests absorption to be more significant than reflection in shaping the spectra. If allowing for the absorbing gas to be either partially covering the continuum emission source or to be ionised, large column densities of the order of 1e(22−24) cm^{−2} are inferred. When the statistics was high enough, virtually every source was found to vary in spectral shape on various time scales, from years to hours. All in all these observational results are compatible with radiation driven accretion disk winds shaping the spectra of these intriguing cosmic sources.

Deciphering the internal structure of prehistoric artefacts can provide spectacular insights that might help us understand the people who made them. In order to preserve the integrity of these relics of past civilisations, it is desirable to make such investigations using non-destructive techniques. Recent decades have witnessed a growth in the X-ray computed tomography (CT) applications in the study of cultural heritage objects. This paper presents and discusses tomographic investigations of two Cucuteni ceramic statuettes discovered in Romania. The study was made with a CT device specially designed for archaeometric applications.

NGC 2617 is a nearby (z ∼ 0.01) active galaxy that recently switched from being a Seyfert 1.8 to be a Seyfert 1.0. At the same time, it underwent a strong increase of X-ray flux by one order of magnitude with respect to archival measurements. We characterize the X-ray spectral and timing properties of NGC 2617 with the aim of studying the physics of a changing-look active galactic nucleus (AGN). We performed a comprehensive timing and spectral analysis of two XMM-Newton pointed observations spaced by one month, complemented by archival quasi-simultaneous INTEGRAL observations. We found that, to the first order, NGC 2617 looks like a type 1 AGN in the X-ray band and, with the addition of a modest reflection component, its continuum can be modeled well either with a power law plus a phenomenological blackbody, a partially covered power law, or a double Comptonisation model. Independent of the continuum adopted, in all three cases a column density of a few 10 23 cm −2 of neutral gas covering 20-40% of the continuum source is required by the data. Most interestingly, absorption structures due to highly ionized iron have been detected in both observations with a redshift of about 0.1c with respect to the systemic redshift of the host galaxy. The redshifted absorber can be ascribed to a failed wind/aborted jets component, to gravitational redshift effects, and/or to matter directly falling towards the central supermassive black hole. In either case, we are probing the innermost accretion flow around the central supermassive black hole of NGC 2617 and might be even watching matter in a direct inflow towards the black hole itself.

Absolute cross sections for the single and double K-shell photoionization of carbonlike O2+ and nitrogenlike
O+ ions were measured in the 526–620-eV photon energy range by employing the ion-photon merged-beam
technique at the SOLEIL synchrotron radiation facility. High-resolution spectroscopy up to E/E ≈ 5300
was achieved. Rich resonance structures observed in the experimental spectra are analyzed and identified with
the aid of R-matrix and multiconfiguration Dirac-Fock (MCDF) methods. For these two atomic oxygen ions
of particular astrophysical interest we characterized the strong 1s → 2p and the weaker 1s → np (n > 2)
resonances observed. A detailed comparison of the energies of the 1s → 2p resonances in the first members of
the oxygen isonuclear sequencemeasured by synchrotron based experiments and the Chandra and XMM-Newton
x-ray satellites is presented

Sadržaj-Kako napreduje razvoj informaciono-komunikacionih tehnologija, tako raste potražnja i interesovanje za uređajima iz ove oblasti. Sistemi za pametne kuće ne pretstavljaju više luksuz već postaju potreba pristupačna svakom čoveku. HiH (House in Hand) ili kuća na dlanu je jedan takav sistem koji omogućava ljudima da sa bilo kog mesta na svetu imaju pregled svojih uređaja kao i mogućnost njihovog upravljanja, Sistem se sastoji od bazne stanice, priključaka, klijentskog softvera i servisa za kontrolu i nadgledanje. Osnovni uređaji i tehnologije koje čine ovaj system su: Arduino razvojno okruženje, nRF24L01+ primopredajnik, Windows Azure cloud platforma i ASP.NET web tehnologija. Realizovan je osnovni prototip ovog sistema kao rezultat istraživanja i rada u oblasti sistema za pametne kuće.

XRF and micro-Raman stratigraphic microanalyses of fragments of some mural paintings, belonging to the Archaeological Site of Oplonti (Napoli) and the Vigna Barberini site in the Palatino (Roma), were performed. In order to collimate the fluorescence X-rays emitted by the samples, an X-ray polycapillary conic collimator (PCC) has been used in front of the detector. This device arrangement is compact, versatile, and portable. The nature of the pigments, the compositional elements, and the thickness of the fragment layers have been studied. The stratigraphic analysis partially confirms the preparation techniques described by Plinius and Vitruvius; moreover it confirms the hypothesis that the artifacts are not fresco paintings. This work has been conducted within the context of a wider research on the Roman age mural paintings.

In the post year 2000 era the technologies that facilitate human communication have rapidly multiplied. While the adoption of these technologies has hugely impacted the behaviour and sociality of people, specifically in urban but also in rural environments, their 'digital footprints' on different data bases have become an active area of research. The existence and accessibility of such large population-level datasets, has allowed scientists to study and model innate human tendencies and social patterns in an unprecedented way that complements traditional research approaches like questionnaire studies. In this review, we focus on data analytics and modelling researchalong the lines of Social Physicsas it has been carried out using the mobile phone datasets to get insight into the various aspects of human sociality, burstiness in communication, mobility patterns, and daily rhythms.

This paper describes the use of Optical Emission Spectroscopy (OES) to measure electron densities and temperatures in nonequilibrium plasmas. The ways to interpret relative lineintensities of neutral argon atoms are evaluated based upon a collisional-radiative model including atomic collisional processes. A conversion from an excitation temperature determined from relative line intensities assuming a Boltzmann population distribution to the thermal electron temperature in the electron temperature range 1-4 eV and electron density range 10 10-10 12 cm-3 is given. Procedures to obtain electron temperature T e and density N e of non-equilibrium argon plasma by OES measurement with collisional radiative model.

It has been developed a model of the DNA in MATLAB, where it has been taken into account each one of the component atoms. It is possible to have a sequence length of even 10000 basis pairs with the possibility for introducing all types of sequences. It was studied the DNA damage in a single strain and in double strain, SSB and DSB respectively as a product of ionising radiation from X-rays when interacting with the DNA immersed in water. This is a theoretical and experimental study in-vitro that quantifies the SSB and DSB with respect to different Gy's of radiation, this allows the understanding and prediction about the exact risks of the exposition. It has been developed for energies corresponding to the 17.6 KeV however the energy parameters are also variable which allows the simulation of all type of ionising radiation. For this simulation it is also taken into account the indirect damage as a product of the free electrons and radicals from the water effects. The information of the spatial distribution of the electrones is obtained form Geant4 and afterwards it is implemented in Matlab where rays are created with tri-dimensional random trajec-tories through Monte Carlo simulations. The experimental confirmation was developed by radiating DNA samples immersed in water with a X-rays unit with Molibdeno target and it is observed and quantified the damage level through Atomic Force Microscopy (AFM). It was obtained a direct relation between the damage and the radiation dose in the experiment and in the model and it is concluded that for 17.6 KeV the deterioration for interaction is observed very low doses but the mutagenic damage only appears until the 17 Gy.