Azimuthal Width Research Articles

Determining the Relationship between the Crescent Visibility Factors and the Coordinates of the Sun and Moon

The study of the relationship between the coordinates of the sun and the moon with the crescent visibility factors has not been previously treated in a detailed and accurate way in research and previous studies, despite its religious importance. Accordingly, this paper aims to study the relationship between the crescent visibility factors (age, lag time, elongation (ARCL), arc of vision or relative altitude (ARCV), relative azimuth (DAZ), and crescent width (W), with coordinates of the sun and the moon), and how it varies during the day of the crescent's observation. In this paper, Matlab programs were designed to calculate the ecliptic sun and moon coordinates (λ, β) and in the presence of all perturbation impacts (planets), then convert these coordinates to the equatorial (α, δ) and horizontal coordinates (A, a). The results were compared with other programs in this field and references such as the ephemeris, accurate times, and astronomical programs. The variation of the sun and moon coordinates (ecliptic, equatorial, and horizontal) was studied with time, and the relationship of those coordinates was explained with visibility crescent factors during the day of the crescent's observation. Finally, the relationship of those factors with each other was studied. The results indicated that there was a relationship between the sun and the moon coordinates with some factors of crescent visibility in critical and standard observations, where the critical observations of the moon (age, lag time, elongation) were increased when the sun and the moon coordinates approach from two equinox points (spring and autumn), while the other factors, such as the relative azimuth and relative altitude, were independent on the change of the coordinates through the year. Also, a relationship was found between the visibility factors with each other, this led to a direct relationship between increasing the elongation with the crescent width. The values of the relative altitude were also increased with the increase in the lag time. Lastly, there was a direct relationship between the increase in the relative azimuth and the relative altitude.

Sb2S3/AlGaAs-based reconfigurable metasurface for dynamic polarization and directionality control of quantum emitter emission.

In this article, we report, to the best of our knowledge, for the first time, phase change material (PCM)-based reconfigurable metasurfaces for tailoring different degrees of freedom (DoF) of the quantum emitter (QE) emission, namely polarization and directionality, two key controlling factors in applications such as quantum computing, communication, and chiral optics. We have used a hybrid plasmon-QE coupled bullseye grating system utilizing the unexplored concept of composite nano-antennas in quantum photonics as the basic building block of the structures. Carefully engineered azimuthal width profile of the Sb2S3/AlGaAs composite ridge and selectively controlled transition of PCM (Sb2S3) states provide dynamic control over the amplitude and phase of the scattered radiation. Based on this methodology, we have designed five different metasurfaces for on-demand switching of target DoFs of QE emission, ensuring high collection efficiency due to the near-field coupling scheme. The first two metasurfaces switch the majority of the outgoing radiation from radially polarized to circularly polarized, whereas the next two switch the direction of circularly polarized outgoing radiation by a maximum of 9.23° while maintaining the spin state (or polarization chirality) in the simulation environment. The third metasurface category is capable of on-demand generation and separation of opposite spin states of outgoing radiation by 11.48° utilizing the selectively controlled phase transition of Sb2S3. Such reconfigurable multi-dimensional manipulation of QE radiation has not been investigated previously. This work proves the vast potential of active metasurfaces to modify the DoFs of QE emission, paving the way for high-dimensional quantum sources for high-speed quantum communication, higher dimensional quantum processing, and switchable chiral optics.

Planet-driven spirals in protoplanetary discs: Limitations of the semi-analytical theory for observations

Context. Detecting protoplanets during their formation stage is an important but elusive goal of modern astronomy. Kinematic detections via the spiral wakes in the gaseous disc are a promising avenue to achieve this goal. Aims. We aim to test the applicability of a commonly used semi-analytical model for planet-induced spiral waves to observations in the low and intermediate planet mass regimes. In contrast to previous works that proposed using the semi-analytical model to interpret observations, in this study we analyse for the first time both the structure of the velocity and density perturbations. Methods. We ran a set of FARGO3D hydrodynamic simulations and compared them with the output of the semi-analytic model in the code WAKEFLOW. We divided the disc into two regions. We used the density and velocity fields from the simulation in the linear region, where density waves are excited. In the non-linear region, where density waves propagate through the disc, we then solved Burgers’ equation to obtain the density field, from which we computed the velocity field. Results. We find that the velocity field derived from the analytic theory is discontinuous at the interface between the linear and nonlinear regions. After ~0.2 rp from the planet, the behaviour of the velocity field closely follows that of the density perturbations. In the low mass limit, the analytical model is in qualitative agreement with the simulations, although it underestimates the azimuthal width and the amplitude of the perturbations, predicting a stronger decay but a slower azimuthal advance of the shock fronts. In the intermediate regime, the discrepancy increases, resulting in a different pitch angle between the spirals of the simulations and the analytic model. Conclusions. The implementation of a fitting procedure based on the minimisation of intensity residuals is bound to fail due to the deviation in pitch angle between the analytic model and the simulations. In order to apply this model to observations, it needs to be revisited so that it can also account for higher planet masses.

A novel optimization method for attenuating multi‐interferences in satellite communication earth station

SummaryThe study of multi‐interferences plays a pivotal role in advancing the development of next‐generation, high‐performance communication devices. In this paper, we propose a design approach for auxiliary antennas aimed at mitigating multi‐interference challenges within satellite communication earth stations. We introduce an eight‐element auxiliary antenna with an elliptical beam comprising dual radiation patches and a T‐shaped power divider, to attenuate interferences originating from three distinct directions. To enhance the azimuthal beamwidth, we adjust the dimensions of the ground plane and extend the substrate. At a frequency of 12.5 GHz, the antenna exhibits a 3‐dB beam spacing of 38° and an azimuthal width of 162°, with a maximum gain of 7.9 dBi. We employ a sidelobe canceller to optimize the antenna's performance, and both simulations and measurements affirm that the auxiliary antenna achieves an extinction interference cancelation ratio exceeding 27 dB under all circumstances.

Relationship of Rock Geomechanics and Coal Mine Slope Safety Factor in South Sumatra Region, Indonesia

The research location is in the coal mine area South Sumatera region, Indonesia. This study aims to determine the geomechanics relationship of the rock which includes the physical properties of the rock: bulk density, and mechanical properties of the rock (shear strength), cohesion and internal shear angle to the safety factor of the coal mine slopes in the study area. Field research is carried out by observing and measuring directly in the field in the following ways: (a) Measuring slope azimuth, slope, dip direction and slope height and width using a measuring tape and geological compass. (b) Rock description based on physical characteristics (megascopic) and rock sampling for testing the physical and mechanical properties of the rock in the laboratory. (c) Observing the general condition of water from rock slopes (dry, moist, watery, wet or flowing) and slope vegetation. 2. Cohesion values and internal shear angles are secondary data obtained from PT. X which has been analyzed in the laboratory. 3. Slope modeling was carried out using Rocscience Slide software. This shows that the smaller the rock density value, the greater the rock cohesion value. The greater the cohesion value of the rock, the smaller the value of the shear angle on the rock. The smaller the value of the shear angle in the rock, the greater the value of the safety factor of the rock slope.

Non-perturbative investigation of low-eccentricity exterior mean motion resonances

ABSTRACT Mean motion resonances are important in the analysis and understanding of the dynamics of planetary systems. While perturbative approaches have been dominant in many previous studies, recent non-perturbative approaches have revealed novel properties in the low-eccentricity regime for interior mean motion resonances of Jupiter in the fundamental model of the circular planar restricted three-body model. Here, we extend the non-perturbative investigation to exterior mean motion resonances in the low-eccentricity regime (up to about 0.1) and for perturber mass in the range of ∼5 × 10−5 to 1 × 10−3 (in units of the central mass). Our results demonstrate that first-order exterior resonances have two branches at low eccentricity as well as low-eccentricity bridges connecting neighbouring first-order resonances. With increasing perturber mass, higher order resonances dissolve into chaos, whereas low-order resonances persist with larger widths in their radial extent but smaller azimuthal widths. For low-order resonances, we also detect secondary resonances arising from small-integer commensurabilities between resonant librations and the synodic frequency. These secondary resonances contribute significantly to generating the chaotic sea that typically occurs near mean motion resonances of higher mass perturbers.

Research on two-dimensional laser warning integrated detection technology

Laser weapons are playing an increasingly important role in modern warfare. To address the growing laser threat, it is necessary to study high-performance two-dimensional laser warning integrated detection technology to achieve simultaneous measurement of two-dimensional directional angle, wavelength and pulse width of incoming laser. This is of great importance for rapid response to security threats. To this end, the paper investigates a two-dimensional laser warning integrated detection system. The measurement principle of the system is as follows: under the condition that the optical system is known, the incidence angle and wavelength of the incoming laser can be judged by the position of the zero-level and first-level diffraction spots, and the mathematical relationship is theoretically derived, so that the principle of laser pulse width measurement based on time-to-digital conversion can be analyzed. For this purpose, firstly, the pulsed laser detection system was designed, the photoelectric conversion of the pulsed laser signal and the time interval measurement were completed, and the pulse width measurement and control unit were experimentally verified. Secondly, the imaging control system of the surface array detector was designed and the imaging effect was verified, and the spot images of lasers with different central wavelengths incident from different angles were collected and the extracted spot center coordinate data were analyzed. Thirdly, the assembly and testing of the two-dimensional laser warning integrated detection system were completed, and the measured wavelength, azimuth, pitch angle and pulse width multi-parameters were tested, and the measurement results were analyzed. The test results show that the system has an azimuth angle of 95°, a pitch angle of 75°, an angular measurement resolution of ≤ 0.5°, a spectral measurement range of 400–1700 nm, and a minimum measurement pulse width of 5 ns, and the two-dimensional laser warning integrated detection system can meet the practical application requirements.

Bioapatite in shark centra studied by wide-angle and by small-angle X-ray scattering.

Members of subclass Elasmobranchii possess cartilage skeletons; the centra of many species are mineralized with a bioapatite, but virtually nothing is known about the mineral's organization. This study employed high-energy, small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS, i.e. X-ray diffraction) to investigate the bioapatite crystallography within blocks cut from centra of four species (two carcharhiniform families, one lamniform family and 1-ID of the Advanced Photon Source). All species' crystallographic quantities closely matched and indicated a bioapatite closely related to that in bone. The centra's lattice parameters a and c were somewhat smaller and somewhat larger, respectively, than in bone. Nanocrystallite sizes (WAXS peak widths) in shark centra were larger than typical of bone, and little microstrain was observed. Compared with bone, shark centra exhibited SAXS D-period peaks with larger D magnitudes, and D-period arcs with narrower azimuthal widths. The shark mineral phase, therefore, is closely related to that in bone but does possess real differences which probably affect mechanical property and which are worth further study.

General balance functions of identified charged hadron pairs of (π,K,p) in Pb–Pb collisions at [formula omitted] 2.76 TeV

First measurements of balance functions (BFs) of all combinations of identified charged hadron (π,K,p) pairs in Pb–Pb collisions at sNN=2.76 TeV recorded by the ALICE detector are presented. The BF measurements are carried out as two-dimensional differential correlators versus the relative rapidity (Δy) and azimuthal angle (Δφ) of hadron pairs, and studied as a function of collision centrality. The Δφ dependence of BFs is expected to be sensitive to the light quark diffusivity in the quark–gluon plasma. While the BF azimuthal widths of all pairs substantially decrease from peripheral to central collisions, the longitudinal widths exhibit mixed behaviors: BFs of ππ and cross-species pairs narrow significantly in more central collisions, whereas those of KK and pp are found to be independent of collision centrality. This dichotomy is qualitatively consistent with the presence of strong radial flow effects and the existence of two stages of quark production in relativistic heavy-ion collisions. Finally, the first measurements of the collision centrality evolution of BF integrals are presented, with the observation that charge balancing fractions are nearly independent of collision centrality in Pb–Pb collisions. Overall, the results presented provide new and challenging constraints for theoretical models of hadron production and transport in relativistic heavy-ion collisions.

Current-driven spiral domain wall in a ferrimagnet near the magnetization compensation point

A spiral domain wall emerges when the Dzyaloshinskii-Moriya vector is along the easy axis. While the ferromagnetic spiral wall has been well studied, its ferrimagnetic counterpart has nevertheless not been explored. Here, using the collective variable approach, we derive the spiral domain-wall solutions in a ferrimagnetic nanostrip with a longitudinal easy axis and a bulk Dzyaloshinskii-Moriya interaction. At the magnetization compensation point, the wall rotates and propagates steadily in a wide current range. The (angular) velocity of this wall increases almost linearly with the experimentally feasible currents. Also, the wall exhibits a relativistic-like contraction with increasing velocity. Near this point, the wall moves smoothly with its velocity linearly depending on the current below the Walker breakdown. Above this critical current, all the internal parameters of the wall, such as the azimuthal angle, width, and spiral pitch, as well as their rates of change, oscillate periodically. The wall moves forward with its velocity varying periodically. These different behaviors at or near the compensation point are ascribed to the tunable demagnetization effect. The adjustability of FiM parameters, combining with the twist induced by the Dzyaloshinskii-Moriya interaction, can effectively change the DW's propagation and rotation.

Mesoscopic scale rearrangements of graphite nanoflake open edges under mild annealing treatments

The paper presents an effect of mild annealing treatments on structural ordering and open edge morphology of graphite nanoflakes (GNF). Thin graphite flakes were obtained from the bulk highly oriented pyrolytic graphite by a prolonged grinding in a pure argon atmosphere and were annealed at T = 670 K for 24 h either in vacuum or in the air. Modification of GNF open edges was studied with high-resolution transmission electron microscopy (HRTEM) and 2D-Fourier analysis of the open edge area HRTEM-images. The morphology of the GNF edges evolve differently under annealing, revealing itself in the azimuthal width of the two-dimensional fast-Fourier transform (2D-FFT) maxima. After annealing in the air, the width decreased, while the vacuum treatment lead to its growth. We relate the former to the open edge flattening via removal of the edge defects by transformation to the gaseous carbon oxides, the latter – to the opposite process of defect accumulation in vacuum with the transformation of the near-edge structure to the less ordered one. The correlation is found between the intensity of the (101) powder X-ray diffraction maximum and the azimuthal width of the FFT-peaks indicating the direct relation of these quantities.

Economy, energy, exergy and mechanical study of co-axial ring shape configuration of legs as a novel structure for cylindrical thermoelectric generator

The n-type and p-type leg structure of any conventional thermoelectric module are in the form of filled rectangular shape which are placed next to the each other (see graphical abstract). In this paper, hollow cylindrical configuration is investigated as a novel leg structure for thermoelectric module in which the n-type and p-type legs are placed co-axial inside each other. A validated 3D numerical simulation was employed to investigate the proposed structure from thermal, economic, exergetic and mechanical viewpoints. The cylindrical ring-shape co-axial configuration can be made in different azimuthal angle, slant angle and width ratio all of which are probed in this research under different boundary conditions. The ring shape structure is able to reduce the thermal-stresses level without the reduction of thermal efficiency. Results indicate that the increment of hot side temperature can improve the output power and conversion efficiency of the cylindrical thermoelectric generator (CTEG) device but reduces the mechanical reliability of the system. It addition, with increment of slant angle of thermoelectric legs, the maximum Von Mises stress in the legs increases and power output of the CTEG is improved. The increase of the width ratio leads to the improvement of the output power and reduction of conversion and exergy efficiencies. Moreover, it is proved that the azimuthal angle of CTEG device has minor impact on the conversion and exergy efficiencies. It is found that the Von Mises stress attains the peak values in the contact regions between wielding layers and hot sides of the legs.

Visual acuity in the flying snake, Chrysopelea paradisi.

Visual control during high-speed aerial locomotion requires a visual system adapted for such behaviors. Flying snakes (genus: Chrysopelea) are capable of gliding at speeds up to 11 m s-1 and perform visual assessments before take-off. Determining nuances of control requires a closed-loop experimental system, such as immersive virtual arenas. To characterize vision in the flying snake Chrysopelea paradisi, we used digitally reconstructed models of the head to determine a 3D field of vision. We also used optokinetic drum experiments and compared slowphase optokinetic nystagmus (OKN) speeds to calculate visual acuity and conducted preliminary experiments to determine whether snakes would respond to closed-loop virtual stimuli. Visual characterization showed that C. paradisi likely has a large field of view (308.5 ± 6.5° azimuthal range), with a considerable binocular region (33.0 ± 11.0° azimuthal width) that extends overhead. Their visual systems are broadly tuned and motion-sensitive, with peak OKN response gains of 0.50 ± 0.11 seen at 46.06 ± 11.08 Hz, and a low spatial acuity, with peak gain of 0.92 ± 0.41 seen at 2.89 ± 0.16 cpd (cycles per degree). These characteristics were used to inform settings in an immersive virtual arena, including framerate, brightness, and stimulus size. In turn, the immersive virtual arena was used to reproduce the optokinetic drum experiments. We elicited OKN in open-loop experiments, with a mean gain of 0.21 ± 0.9 seen at 0.019 ± 6x10-5 cpd and 1.79 ± 0.01 Hz. In closed-loop experiments, snakes did not exhibit OKN, but held the image fixed, indicating visual stabilization. These results demonstrate for that C. paradisi responds to visual stimuli in a digital virtual arena. The accessibility and adaptability of the virtual setup make it suitable for future studies of visual control in snakes and other animals in an unconstrained setting.

Determination of the Surface Facets of Gold Nanorods in Wet‐Coated Thin Films with Grazing‐Incidence Wide Angle X‐Ray Scattering

AbstractThis work studies the surface facets of gold nanorods (AuNRs) in wet‐coated nanoparticle thin films with synchrotron‐light‐based grazing‐incidence wide angle X‐ray scattering (GIWAXS), which provides statistically relevant results on many nanoparticles. Air‐brush spraying deposits the monodisperse AuNRs into sparse monolayers where the long axis of rods is parallel to the substrate surface. It is found that the crystalline facets of individual AuNRs in the sparse monolayer are all in the same orientation, as indicated by narrow azimuthal widths of (200) reflections, over a macroscopic scale comparable to the substrate. This alignment is probably due to the rods' sitting on high‐index surface facets such as (520) and (250). A quantitative analysis of the angles between bulk facets and the surface facets leads to a “nested‐octagon” model for the cross sections of AuNRs: shell octagon with high‐index crystalline facets (520), (5‐20), (2‐50), (‐2‐50), (‐5‐20), (‐520), (‐250), and (250), and core octagon consisting of low‐index crystalline facets (100), (1‐10), (0‐10), (‐1‐10), (‐100), (‐110), (010), and (110).

Electron Energization by Parallel Electric Fields in Poloidal Standing Waves

AbstractA hybrid gyrofluid‐kinetic electron model is adapted and used to simulate poloidal standing modes for different electron temperatures and azimuthal mode numbers. As in previous studies of toroidal standing modes, mirror force effects lead to increased parallel potential drops, monoenergetic electron energization, and wave energy dissipation as the ambient electron temperature is increased. A similar trend is also observed when the electron temperature is held fixed and the azimuthal mode number increased—owing to the narrowing of the azimuthal flux tube width, which necessitates more electron energization to carry the increased parallel current density. In both cases, the increase in electron energization eventually leads to more rapid decreases in the parallel current with time because of the dissipation of wave energy.

Balance functions of (un)identified hadrons in Pb–Pb, p–Pb, and pp collisions at the LHC

In ultrarelativistic heavy-ion collisions, correlations of particles with opposite quantum numbers provide insight into quark production mechanisms and time scales, collective motion, and re-scattering in the hadronic phase. The longitudinal and azimuthal widths of balance functions for charged kaons and charged pions are used to examine the two-wave quark production model proposed to explain quark-antiquark production within the QGP, which predicts a large increase in up and down quark pairs relative to strange quark pairs around the time of hadronization. Balance functions are also analyzed in small collision systems such as p–Pb and pp to study fragmentation effects and possible collective effects in high-multiplicity events. A comprehensive set of balance functions has been measured using the ALICE detector, including results for unidentified hadrons in Pb–Pb and p–Pb collisions at sNN=5.02TeV, for charged pions in Pb–Pb collisions at sNN=2.76TeV, p–Pb collisions at sNN=5.02TeV and pp collisions at s=7TeV, and for charged kaons in Pb–Pb collisions at sNN=2.76TeV. The first balance function yield results are also presented.

Research on the effect of magnet parameters on the isochronous field of a superconducting cyclotron

It is a complicated task to obtain an isochronous field of a cyclotron magnet. Due to non-linear property of iron, iterated simulation of magnet design takes a long time to get an isochronous field. As an example, for a magnet design of a 240 MeV (SC240) superconducting cyclotron, the effect of main parameters of a magnet system on the magnetic field was studied, among them the azimuthal sector width, the spiral sector angle, the gap between sectors, the depth of valley region, the position of the coil, the shape of the coil and the excited current of the superconducting coil. It was found that the azimuthal average magnetic field can be increased by any of the following methods, including enlarging azimuthal width, increasing excited current of the superconducting coil, narrowing of the gap between sectors, reducing the depth of the valley region or decreasing the distance between the coil and the mid-plane. In addition, axial oscillation frequency can be improved by increasing the spiral angle, the depth of the valley region, or decreasing the gap between sectors.

On Resonance Contribution to Balance Functions

It is known that resonance decays influence the shape of the charge-balance functions measured in hadronic collisions. That is reflected in their rapidity and azimuthal widths and the integral, and therefore has consequences for different model interpretations. In this paper, we show that the contribution from neutral resonance decays can be removed from the balance function in an analytical way, and test the performance of the removal procedure with PYTHIA events. Prospects for applications of the procedure to real data analysis of balance functions are also discussed.

Cm-wavelength observations of MWC 758: resolved dust trapping in a vortex

The large crescents imaged by ALMA in transition disks suggest that azimuthal dust trapping concentrates the larger grains, but centimetre-wavelengths continuum observations are required to map the distribution of the largest observable grains. A previous detection at ~1cm of an unresolved clump along the outer ring of MWC758 (Clump1), and buried inside more extended sub-mm continuum, motivates followup VLA observations. Deep multiconfiguration integrations reveal the morphology of Clump 1 and additional cm-wave components which we characterize via comparison with a deconvolution of recent 342GHz data (~1mm). Clump1, which concentrates ~1/3 of the whole disk flux density at ~1cm, is resolved as a narrow arc with a deprojected aspect ratio Chi>5.6, and with half the azimuthal width than at 342 GHz. The spectral trends in the morphology of Clump1 are quantitatively consistent with the Lyra-Lin prescriptions for dust trapping in an anticyclonic vortex, provided with porous grains (f~0.2+-0.2) in a very elongated (Chi~14+-3) and cold (T~23+-2K) vortex. The same prescriptions constrain the turbulence parameter alpha and the gas surface density Sigma_g through log10( alpha x Sigma_g /g/cm2)~-2.3+-0.4, thus requiring values for Sigma_g larger than a factor of a few compared to that reported in the literature from the CO isotopologues, if alpha <~ 1E-3. Such physical conditions imply an appreciably optically thick continuum even at cm-wavelengths (tau(33GHz)~0.2). A secondary and shallower peak at 342GHz is about twice fainter relative to Clump1 at 33GHz. Clump2 appears to be less efficient at trapping large grains.

Evidence for a massive dust-trapping vortex connected to spirals

Context. Spiral arms, rings and large scale asymmetries are structures observed in high resolution observations of protoplanetary disks, and it appears that some of the disks showing spiral arms in scattered light also show asymmetries in millimeter-sized dust. HD 135344B is one such disk. Planets are invoked as the origin of these structures, but no planet has been observed so far and upper limits are becoming more stringent with time. Aims. We want to investigate the nature of the asymmetric structure in the HD 135344B disk in order to understand the origin of the spirals and of the asymmetry seen in this disk. Ultimately, we aim to understand whether or not one or more planets are needed to explain such structures. Methods. We present new ALMA sub-0.1′′ resolution observations at optically thin wavelengths (λ = 2.8 and 1.9 mm) of the HD 135344B disk. The high spatial resolution allows us to unambiguously characterize the mm-dust morphology of the disk. The low optical depth of continuum emission probes the bulk of the dust content of the vortex. Moreover, we have combined the new observations with archival data at shorter wavelengths to perform a multi-wavelength analysis and to obtain information about the dust distribution and properties inside the observed asymmetry. Results. We resolve the asymmetric disk into a symmetric ring + asymmetric crescent, and observe that (1) the spectral index strongly decreases at the centre of the vortex, consistent with the presence of large grains; (2) for the first time, an azimuthal shift of the peak of the vortex with wavelength is observed; (3) the azimuthal width of the vortex decreases at longer wavelengths, as expected for dust traps. These features allow confirming the nature of the asymmetry as a vortex. Finally, under the assumption of optically thin emission, a lower limit to the total mass of the vortex is 0.3MJupiter. Considering the uncertainties involved in this estimate, it is possible that the actual mass of the vortex is higher and possibly within the required values (~4 MJupiter) to launch spiral arms similar to those observed in scattered light. If this is the case, then explaining the morphology does not require an outer planet.