Incident Photon Energy Research Articles

Resonant photoemission spectroscopy of the ferromagnetic Kondo system CeAgSb2

We study the electronic structure of single crystal CeAgSb2, a low T c ferromagnetic Kondo system, using synchrotron radiation photoemission spectroscopy (PES) and x-ray absorption spectroscopy (XAS). We have carried out Ce 5s, Ce 5p, Sb 4d core level PES as well as Ce 4d–4f resonant PES of the valence band states of CeAgSb2. We also report the resonant PES behavior of Ce 5s and 5p core-levels and the simultaneous intensity suppression of Sb 4d core-level and Ag 4d valence band states across the Ce 4d–4f threshold. The Ce 4d–4f resonant valence band spectra show typical f 0 and f 1 features associated with Kondo behavior. The constant initial state spectra of the f 0 and f 1 features show maxima at different incident photon energies, arising from different relative contributions of surface and bulk character Ce 4f partial density of states. XAS across the Ce 3d–4f M-edge also shows the corresponding final state f 1 and f 2 features. The weak temperature dependence of the XAS spectra between T = 25 K and 300 K could be simulated using a full multiplet calculation combined with a simplified single-impurity Anderson model approach. The calculations confirm the Kondo screening and allows quantification of the bulk Ce 4f electron count in CeAgSb2. The Ce 5s states show an exchange splitting which reflects the local magnetic moment of Ce 4f states. The overall results characterize the bulk and surface sensitive Ce 4f states, and indicate the role of Kondo effect in forming the moderately enhanced heavy-fermion carriers in CeAgSb2.

Tunable and highly sensitive temperature sensor based on graphene photonic crystal fiber* *Project supported by the National Natural Science Foundation of China (Grant Nos. 52021006, 52025023, 51991342, and 11888101), the Key R&D Program of Guangdong Province, China (Grant Nos. 2019B010931001, 2020B010189001, and 2018B030327001), the Pearl River Talent Recruitment Program of Guangdong Province, China (Grant No. 2019ZT08C321), the Strategic Priority Research

Optical fiber temperature sensors have been widely employed in enormous areas ranging from electric power industry, medical treatment, ocean dynamics to aerospace. Recently, graphene optical fiber temperature sensors attract tremendous attention for their merits of simple structure and direct power detecting ability. However, these sensors based on transfer techniques still have limitations in the relatively low sensitivity or distortion of the transmission characteristics, due to the unsuitable Fermi level of graphene and the destruction of fiber structure, respectively. Here, we propose a tunable and highly sensitive temperature sensor based on graphene photonic crystal fiber (Gr-PCF) with the non-destructive integration of graphene into the holes of PCF. This hybrid structure promises the intact fiber structure and transmission mode, which efficiently enhances the temperature detection ability of graphene. From our simulation, we find that the temperature sensitivity can be electrically tuned over four orders of magnitude and achieve up to ∼ 3.34 × 10−3 dB/(cm⋅°C) when the graphene Fermi level is ∼ 35 meV higher than half the incident photon energy. Additionally, this sensitivity can be further improved by ∼ 10 times through optimizing the PCF structure (such as the fiber hole diameter) to enhance the light–matter interaction. Our results provide a new way for the design of the highly sensitive temperature sensors and broaden applications in all-fiber optoelectronic devices.

The response of thick (10 μm) AlInP x-ray and γ-ray detectors at up to 88 keV

The development of new x-ray and γ-ray spectrometers based on AlInP photodiodes with increased quantum detection efficiency and improved energy resolution is reported. The spectroscopic responses of two AlInP p+–i–n+ mesa photodiodes (10 μm i layer, the thickest so far reported) were investigated at photon energies from 4.95 to 88.03 keV; the detectors and preamplifier were operated at 30 °C. Energy resolutions (full width at half maximum) of 750 ± 40 eV and 850 ± 30 eV at 4.95 keV were achieved with the two detectors. The energy resolution deteriorated with increasing photon energy; this was in accordance with the increasing Fano noise with energy and suggested negligible incomplete charge collection noise across the photon energy range investigated. The measured voltage output of each spectrometer was found to be linear as a function of incident x-ray photon energy. The count rate (measured at 8.63 keV) was also found to linearly increase with incoming x-ray photon flux for the investigated spectrometers. These results, which were obtained using the thickest AlInP photodiodes produced so far, suggest that AlInP detectors are highly promising candidates for future uncooled x-ray and γ-ray spectrometers.

Electronic structure of URu2Si2 in paramagnetic phase: three-dimensional angle resolved photoelectron spectroscopy study

The three-dimensional (3D) electronic structure of the hidden order compound URu2Si2 in a paramagnetic phase was revealed using a 3D angle-resolved photoelectron spectroscopy where the electronic structure of the entire Brillouin zone is obtained by scanning both incident photon energy and detection angles of photoelectrons. The quasi-particle bands with enhanced contribution from the U 5f state were observed near E F, formed by the hybridization with the Ru 4d states. The energy dispersion of the quasi-particle band is significantly depend on k z , indicating that they inherently have a 3D nature. The band-structure calculation qualitatively explain the characteristic features of the band structure and Fermi surface although the electron correlation effect strongly renormalizes the quasi-particle bands. The 3D and strongly-correlated nature of the quasi-particle bands in URu2Si2 is an essential ingredient for modeling its hidden-order transition.

(Invited) Probing the Electronic Structure of Oxide Electrocatalysts and the Formation of Reaction Intermediates

Perovskite oxides (ABO3) are highly active for the oxygen evolution reaction (OER). Activity is observed to correlate with changes in bulk electronic structure parameters, such as metal-oxygen covalency and transition metal oxidation state. We employ spectroscopic approaches to consider such descriptors at the surface of perovskite oxides in situ, as well as their implications on the formation of surface adsorbates proposed to act as reaction intermediates during the OER.Many surface science techniques, such as X-ray photoelectron spectroscopy (XPS), collect information from inherently surface-sensitive low-energy processes, requiring operation in ultrahigh vacuum. This constraint is lifted for ambient pressure XPS, which can probe the surface in equilibrium with the gas phase at pressures up to ~a few Torr, or with thin liquid layers using a higher incident photon energy. This presentation will discuss the insights obtained with this technique regarding the electronic structure of oxide electrocatalysts in an oxidizing or humid environment, as well as the reaction intermediates of relevance to electrocatalysis.1 We will then extend the technique to probe electrocatalysts in operando,2 driving current through a thin layer of liquid electrolyte and employing a tender X-ray source.

Innovative Implementation of an Alternative Tetrathiafulvene Derivative for Flexible Indium Phthalocyanine Chloride-Based Solar Cells.

Herein, we present the photovoltaic properties of an indium phthalocyanine chloride (InClPc)-based flexible planar heterojunction device, introducing the tetrathiafulvene derivative 4,4′-Dimethyl-5,5′-diphenyltetrathiafulvalene (DMDP-TTF) as the electron donor layer. UV-vis spectroscopy is widely used to characterize the electronic behavior of the InClPc/DMDP-TTF active layer. The interactions between the DMDP-TTF and phthalocyanine are predominantly intermolecular and the result of the aggregation of InClPc. Tauc bands were obtained at 1.41 and 2.8 eV; these energy peaks can result in a charge transfer ascribed to the transition from the DMDP-TTF to π-orbitals that are associated with the phthalocyanine ring or even with the same indium metal center. Conductive carbon (CC) was used for the cathode. Finally, an indium tin oxide (ITO)/InClPc/DMDP-TTF/CC device was fabricated by high-vacuum thermal evaporation onto a flexible substrate and the photovoltaic properties were evaluated. A diode type I-V curve behavior was observed with a photovoltaic response under illumination. A generated photocurrent of 2.25 × 10−2 A/cm2 was measured. A conductivity reduction with the incident photon energy from 1.61 × 10−7 S/cm to 1.43 × 10−7 S/cm is observed. The diode resistance presents two different behaviors with the applied voltage. A VTFL of 5.39 V, trap concentration of 7.74 × 1016 cm−3, and carrier mobility values of ~10−6 cm2/V s were calculated, showing improved characteristics via the innovative implementation of an alternative TTF-derivative, indicating that the DMDP-TTF has a strong interaction at the junction where free available states are increased, thus inducing higher mobilities due to the large number of π-orbitals, which indicates the feasibility of its use in solar cells technology.

Modeling photon-induced reactions on U233–238 actinide targets

Comprehensive calculations of cross sections of photon induced reactions on $^{233-238}$U targets for incident photon energies from 3 up to 30 MeV are undertaken with the statistical model code EMPIRE-3.2 Malta. Results are compared with the experimental data from EXFOR and with the current evaluations. The differences and the similarities between the models and parameters used in calculations of photon- and neutron-induced reactions on the same nuclei are discussed with focus on fission. The role of the extended optical model for fission in improving the description of the measured data and in determining consistent sets of barrier parameters is pointed out.

Studyof the Spin-Orbit Interaction Effects on Energy Levels and the Absorption Coefficients of Spherical Quantum Dotand Quantum Anti-Dotunderthe Magnetic Field

In this study, the energy levels of spherical quantum dot (QD) and spherical quantum anti-dot (QAD) with hydrogenic impurity in the center, in the presence of spin-orbit interaction (SOI) and weak external magnetic field have been studied. To this aim, solving the Schrodinger equation for the discussed systems by using the finite difference method, the wave functions and energies of these systems are calculated. Then the effect of the external magnetic field, system radius size and height of potential barrier on the energy levels and also the linear, nonlinear and total absorption coefficients, (ACs), of the mentioned systems are studied. Numerical results show that the SOI in both models causes a split of 2p level into two sub-levels of 2p_(1/2)and 2p_(3/2) where the low index indicates the total angular momentum J. Also, considering the electron spin, under an applied magnetic field, the 1s and 2p levels split into two sub-levels and six sub-levels, respectively. Furthermore, in this research, it is proved that energy changes are significantly different as a function of radius size and height of the potential barrier in QD and QAD models and the ACs of these systems behave differently according to the incident photon energy at the same condition.

SYNTHESIS AND CHARACTERIZATION OF (ZNO)–(CO3O4) NANOCOMPOSITE VIA SPRAY PYROLYSIS PROCESS: THE USE OF THE BRUGGEMAN MODEL ON OPTICAL PROPERTIES PREVISION

In the present paper, (ZnO)–(Co3O4) nanocomposite thin films have been prepared by using spray pyrolysis deposition on a glass substrate at 350∘C. After that, the as-obtained films have been characterized and analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and the double beam UV-visible (UV-vis) spectrophotometer. Furthermore, the Bruggeman model is used to predict the evolution of the optical dielectric constant (real and imaginary parts: [Formula: see text] and [Formula: see text] to compare them with those obtained from the experimental results. The XRD pattern reveals that the nanocomposite film has diffraction peaks 2[Formula: see text], 36.95∘ corresponding respectively to the (220), (311) planes of cubic Co3O4 and another about of 2[Formula: see text] corresponding to the (101) plane of Wurtzite ZnO. Using the Debye Scherrer formula, the crystallite size of (ZnO)[Formula: see text]–(Co3O[Formula: see text] nanocomposite is found about 32[Formula: see text]nm, while the obtained thickness of this nanocomposite is about 780[Formula: see text]nm using the DekTak Stylus profilometer. Besides, the morphology analysis shows that the nanocomposite sample is well covered without holes and/or cracks and it has uniform dense grains. The evaluation of the transmittance, reflectance, refraction index, extinction coefficient, real and imaginary parts of dielectric constant as function of wavelength illustrates that the optical response of nanocomposite thin film (ZnO)[Formula: see text]–(Co3O[Formula: see text] depends on the influence of two mediums of pure materials ZnO and Co3O4 and their interaction. In addition, the direct band gap vs incident photon energy obtained from the Tauc plot equation shows that this nanocomposite has three values of band gap energy which are [Formula: see text][Formula: see text]eV, [Formula: see text][Formula: see text]eV (correspond to pure Co3O4 film) and [Formula: see text][Formula: see text]eV (correspond to pure ZnO film). Besides, the application of the Bruggeman equation indicates that the influence of the values of volume concentration and optical dielectric constant of the ingredient nanomaterials (ZnO and Co3O[Formula: see text] is significant on the value of the effective dielectric constant of nanocomposite thin film. The specific result of this study is the similarity between the spectra obtained from the Bruggeman model and the measured one, which proves that the application of this model is useful for the prediction of the optical properties of the composite.

Three cobalt(II) porphyrins ligated with pyridyl-containing nanocarbon/gold(III) porphyrin for solar cells: Synthesis and characterization

Three new donor–acceptor systems, synthesized by axial coordination of 1-N-methyl-2-(pyridin-4-yl)-3,4-fullero[60]pyrrolidine (PyC60)/2,5-di-(pyridin-2-yl)-3,4-fullero[70]pyrrolidine (Py2C70) and meso-tetra(4-pyridyl)porphyrinato)gold(III) chloride (ClAuP) with (meso-tetra(4-octyloxyphenyl)porphyrinato)cobalt(II) (CoP) were observed. In order to optimize the reaction conditions, the formation mechanism and composition of the complexes dependent on the structure of axial molecular ligand were explored. The triad, (PyC60)2CoP/(Py2C70)2CoP, and dyad, (ClAuP)CoP, were formed respectively in the two-stage and one-stage process. The confirmation of their chemical structure and determination of stability constants was performed using the UV–vis, IR, 1H NMR, MS (MALDI-TOF) spectrometry and chemical thermodynamics/kinetics, respectively. Photoelectrochemical studies of the porphyrin-fullerene/porphyrin-porphyrin systems were carried out compared with corresponding precursors by the amperometry methods. The high values of the photocurrent density and incident photon energy conversion to current (IPCE365nm) of the titanium electrode modified by (PyC60)2CoP/(Py2C70)2CoP/(ClAuP)CoP were demonstrated, which points to good perspectives in the application of the coordination complexes synthesized as a photoactive molecular material for solar cells.

Tuning Optoelectronic Properties of Double Quantum Dot Structure Using Tight-Binding Model for Photo-Electric Applications

In electronics field, researchers and industries have been working to fabricate low-cost optoelectronic devices by using less materials in the fabrication process. Thus, miniaturization concept has been used in the design and synthesis of the fabricated materials and devices based on nano-dimension. However, reducing the used materials would affects the overall performance of the devices and new building blocks materials are needed to pass the performance capacity limits of current silicon-based materials. Quantum Dots DQs have been introduced and attracted much attention among researchers because of their unique characteristics that are necessary for many potential applications by using nano-dimensions structures. These properties include size-tunable optical and other electronic characteristics that are not found in the current bulk materials. Although there has been interested QDs experimental studied that have been already carried out, different theoretical efforts must be introduced in order to provide good understanding of the possible and different QDs applications. In this work, therefore, optoelectronic properties of Double Quantum Dots DQDs system were studied theoretically to provide important information about the possibility of using this system in photoelectric applications. A tight-binding framework was adopted to describe the system, and all the calculations were carried out based on the steady state formalism. The proposed DQD structure was connected to metallic leads and studied to investigate the QD size dependent. The transmission calculation presented first through the electron transport mechanism. Tunneling current and conductance were then presented to provide general understanding about the behavior of the proposed system. A correlation of transmission, current and conductance results with QD radius R, incident photon energy Eph, Temperature and bias voltage have been identified. Therefore, this correlation is strongly supporting the proposal of using DQD system in fabricating nanoscale photovoltaic devices, particularly, solar cells.

Simulation of the interaction of intense ultrashort X-ray laser pulses with micro-sized Al targets

We study the interaction of extremely short and high-intensity X-ray pulses with a 1.0μm thick Al foil. Four pulse lengths – 100 fs, 200 fs, 300 fs, and 400 fs – are considered. The photon energy is 1830 eV and the pulse intensity is 1017W/cm2. The interaction dynamics are calculated via a radiation hydrodynamic code. The X-ray laser pulse heats the target isochorically. It generates a homogeneous hot dense matter; electrons are hotter than ions. The simulation of the interaction of pump and probe pulses with a delay time in the fs scale provides that the probe pulse heats the target significantly. A Monte-Carlo method is used to provide a microscopic description; the electron distribution function shows a two-temperature system. The electron distribution has spikes at the energy difference between the k-edges of Al ions and the energy of incident photons. The energies of these spikes depend on the considered ionization depression model. The Chihara formula and the non-equilibrium random phase approximation are utilized to calculate the X-ray Thomson scattering spectrum (XRTS). For collective scattering, the plasmon peaks are a function of the pulse lengths and the electron distribution function. Therefore, when XRTS is fitted to a measured spectrum may give the target density, the target temperature, and the microscopic electron distribution function.

Electric field to control light scattering on semiconductor QWW

In this work, the study of an external electric field to control the electron Raman scattering in a semiconductor quantum well wire with a cylindrical symmetry grown in a GaAs/Al0.35Ga0.65As matrix is presented. In our model we considered an transversal electric field to the axis of the system. To illustrate our calculations a single electron in the conduction band, that is parabolic and unfolds in a system of sub-bands due to confinement is considered. This approach assumed the results previously obtained by our group where the behavior of the electron states energy, εr, as a function of the electric field and the confinement radius was demonstrated. The unfolding of the electron states, the selection rules elimination, and the positions of the singularities with the change of the electric field for a fixed confinement radius were visible in the emission spectra. Finally, the quantum efficiency and the characteristics of a secondary radiation source based on electron Raman scattering process in a semiconductor quantum well wire with fixed confinement radius, electric field intensity, and incident photon energy to operate properly with the best efficiency, are established.

Study on the series resistance of crystal violet dye-based organic photovoltaic device in presence of single walled carbon nanotubes

The series resistance (Rs) of any organic photovoltaic device (OPV) plays an important role on the device performance. Generally, the electrode and the presence of traps at the interface contribute the high Rs. In this present work, we have studied the Rs of crystal violet dye-based OPV device and its variation in the presence of single walled carbon nanotubes (SWCNT). From the dark current voltage (I–V) characteristics, we have extracted Rs by using the Cheung–Cheung method. It is observed that the trap energy (Ec) and the value of Rs are decreased in the presence of SWCNT. The values of Rs and Ec are about 0.246 MΩ and 0.085 eV in the absence of SWCNT and these values change to 0.124 MΩ and 0.060 eV, respectively, in the presence of SWCNT. The light I–V characteristics of the devices have also been studied to find out the Rs of the device under illumination. Under illumination, the charge transport process is governed by the incident photon energy (Em) which is absorbed by the OPV device. So we have extracted the Em from the light I–V characteristics and estimated the Rs by using area method under light illumination in the absence and presence of SWCNT. It is observed that the extracted values of Rs under illumination are low compared to the values of Rs measured from dark I-V characteristics.

Structural and optoelectronic properties of cubic Zn1-x-yBexMgySe quaternary alloys nearly lattice matched to GaAs substrate: A density functional investigation

Density functional calculations of structural and optoelectronic properties of cubic Zn1-x-yBexMgySe quaternary alloys are carried out considering their nearly lattice matching to GaAs substrate. Calculations ensure that each quaternary alloy is a direct band gap (Γ−Γ) semiconductor. The mBJ-GGA based computed minimum band gap of each alloy is larger that with EV-GGA scheme. Enhancement in beryllium or magnesium composition nonlinearly reduces the lattice constant, but enhances the bulk modulus and minimum band gap of quaternary alloys. Lower effective mass of electrons compared to holes confirms dominant role of electrons in carrier transportation in each specimen. Electronic transitions from occupied Se-4p state of valence band to unoccupied Zn-5s, Mg-3p, Mg-4s, Be-2p and Be-3s states of conduction band collectively contribute intense peaks in ε2(ω) spectra of each quaternary alloy. Quaternary semiconductor with higher band gap possesses lower value of zero-frequency limits in ε1(ω), n(ω) and R(ω) spectra, but requires higher critical point energies in ε2(ω), k(ω), σ(ω) and α(ω) spectra and vice versa. Computed oscillator strength of each quaternary alloy confirms the presence of sufficient number (>200) of electrons in the unoccupied states of conduction band above 27.0 eV of incident photon energy during any optical excitation.

Harmonic generation predominantly from a single spin channel in a half metal

Harmonic generation in atoms and molecules has reshaped our understanding of ultrafast phenomena beyond the traditional nonlinear optics and has launched attosecond physics. Harmonics from solids represent a new frontier, where both majority and minority spin channels contribute to the harmonics. This is true even in a ferromagnet whose electronic states are equally available to optical excitation. Here, we demonstrate that harmonics can be generated mostly from a single spin channel in half-metallic chromium dioxide. An energy gap in the minority channel greatly reduces the harmonic generation, so the harmonics predominantly emit from the majority channel, with a small contribution from the minority channel. However, this is only possible when the incident photon energy is well below the energy gap in the minority channel, so all the transitions in the minority channel are virtual. The onset of the photon energy is determined by the transition energy between the dipole-allowed transition between the $\mathrm{O}\text{\ensuremath{-}}2p$ and $\mathrm{Cr}\text{\ensuremath{-}}3d$ states. The harmonics mainly from a single spin channel can be detected, regardless of laser field strength, as long as the photon energy is below the minority band energy gap. This prediction should be tested experimentally.

First measurement of the asymmetry and the Gerasimov-Drell-Hearn integrand from the He3⃗(γ⃗,p)H2 reaction at an incident photon energy of 29 MeV

The first measurement of the $\vec{^3He}(\vec{\gamma},p)d$ process was performed at the High Intensity $\gamma$-ray Source (HI$\gamma$S) facility at Triangle Universities Nuclear Laboratory (TUNL) using a circularly polarized, monoenergetic $\gamma$-ray beam and a longitudinally polarized $^3$He target. The spin-dependent asymmetry and the contribution from the two-body photodisintegration to the $^3$He Gerasimov-Drell-Hearn integrand are extracted and compared with state-of-the-art three-nucleon system calculations at the incident photon energy of 29.0 MeV. The data are in general agreement with the various theoretical predictions based on the Siegert theorem or on explicit inclusion of meson-exchange currents.

Theoretical Determination of High-Energy Photon Attenuation and Recommended Protective Filler Contents for Flexible and Enhanced Dimensionally Stable Wood/NR and NR Composites.

This work aimed to theoretically determine the high-energy-photon-shielding properties of flexible wood/natural rubber (NR) and NR composites containing photon protective fillers, namely Pb, Bi2O3, or Bi2S3, using XCOM. The properties investigated were the mass attenuation coefficient (µm), linear attenuation coefficient (µ), and half value layer (HVL) of the composites, determined at varying photon energies of 0.001–5 MeV and varying filler contents of 0–1000 parts per hundred parts of rubber by weight (phr). The simulated results, which were in good agreement with previously reported experimental values (average difference was 5.3%), indicated that overall shielding properties increased with increasing filler contents but decreased with increasing incident photon energies. The results implied the potential of bismuth compounds, especially Bi2O3, to replace effective but highly toxic Pb as a safer high-energy-photon protective filler, evidenced by just a slight reduction in µm values compared with Pb fillers at the same filler content and photon energy. Furthermore, the results suggested that the addition of 20 phr wood particles, primarily aimed to enhance the rigidity and dimensional stability of Pb/NR, Bi2O3/NR, and Bi2S3/NR composites, did not greatly reduce shielding abilities; hence, they could be used as dimensional reinforcers for NR composites. Lastly, this work also reported the optimum Pb, Bi2O3, or Bi2S3 contents in NR and wood/NR composites at photon energies of 0.1, 0.5, 1, and 5 MeV, with 316–624 phr of filler being the recommended contents, of which the values depended on filler type and photon energy of interest.

Optical Tuning of Resistance Switching in Polycrystalline Gallium Phosphide Thin Films.

The nanoscale resistive switching characteristics of gallium phosphide (GaP) thin films directly grown on Si are investigated as a function of incident light. The formation of conductive channels along the grain boundaries is attributed to the presence of point defects and structural disorder, which provide the ideal environment to enable the filamentary switching process. Both first-principles calculations and UV-vis and photoluminescence spectroscopy strongly point to the possibility of mid-gap electronic states in the polycrystalline GaP film due to such defects. To study the photonic excitation, photoconductive atomic force microscopy (phAFM) measurement is conducted. We observe photocurrents even for incident photon energies lower than the band gap, consistent with the presence of mid-gap electronic states; the photocurrents increase in direct proportion to the incident photon energy with a concomitant decrease in the filament resistance. This demonstrates GaP directly integrated on Si can be a promising photonic resistive switching materials system.

Theoretical angular dependence of L3 sub-shell X-rays following photoionization

Angular distribution studies are made for L3 sub-shell X-rays of high Z elements; W, Pt, Hg, Pb, and U in the angular span 0°–180° at incident photon energies; near L3 edge, where considerable anisotropy is anticipated and at 60 keV, the energy of experimental interest from standard laboratory source Am-241. Angular distribution of X-rays originating from L3 sub-shell vacancies for each element is derived from theoretical alignment parameter already evaluated under non-relativistic dipole approximation (NDA) in a point Coulomb potential (A20) and in a screened Coulomb potential (A20*) that accommodates the effect of screened nuclear drag on electron wave function, and analytical perturbation theory (A20**). The normalized Lℓ and Lα intensity distributions show more anisotropy at L3 threshold than at 60 keV for all the elements and under all theoretical models. Besides this, the anisotropy for Lℓ is larger than Lα which comprises the unresolved Lα1 and Lα2 lines with opposite anisotropy. The angular distribution trends are almost similar for all the elements. The anisotropy values at L3 threshold energy are assuredly greater than the reported experimental uncertainties (5–8 %) of X-ray intensities. Anisotropy magnitude is found sensitive to the theoretical models. The present anisotropy trends resemble the results of Zhang et al (Journal of Quantitative Spectroscopy and Radiative Transfer, 244 (2020) 106844), however, the values are not quite same.