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The use of parallel manipulators in aerospace engineering has gained significant attention due to their ability to provide improved stability and precision. This paper presents the design, control, and analysis of 'STEWIE', which is a three-degree-of-freedom (DoF) parallel manipulator robot developed by members of the thrustMIT rocketry team, as a payload stabilization mechanism for their sounding rocket, 'Altair'. The goal of the robot was to demonstrate the attitude control of the parallel plate against the continuous change in orientation experienced by the rocket during its flight, stabilizing the payloads. At the same time, the high gravitational forces (G-forces) and vibrations experienced by the sounding rocket are counteracted. A novel design of the mechanism, inspired by a standard Stewart platform, is proposed which was down-scaled to fit inside a 4U CubeSat within its space constraints. The robot uses three micro servo motors to actuate the links that control the alignment of the parallel plate. In addition to the actuation mechanism, a robust control system for its manipulation was developed for the robot. The robot represents a significant advancement in the field of space robotics in the aerospace industry by demonstrating the successful implementation of complex robotic mechanisms in small, confined spaces such as CubeSats, which are standard form factors for large payloads in the aerospace industry., Comment: For code and design files, refer to https://github.com/utkarshanand140/Stewie-Robot

We present a search for long-lived particles (LLPs) produced from kaon decay that decay to two muons inside the ICARUS neutrino detector. This channel would be a signal of hidden sector models that can address outstanding issues in particle physics such as the strong CP problem and the microphysical origin of dark matter. The search is performed with data collected in the Neutrinos at the Main Injector (NuMI) beam at Fermilab corresponding to $2.41\times 10^{20}$ protons-on-target. No new physics signal is observed, and we set world-leading limits on heavy QCD axions, as well as for the Higgs portal scalar among dedicated searches. Limits are also presented in a model-independent way applicable to any new physics model predicting the process $K\to \pi+S(\to\mu\mu)$, for a long-lived particle S. This result is the first search for new physics performed with the ICARUS detector at Fermilab. It paves the way for the future program of long-lived particle searches at ICARUS.

We report results of magnetization and $^{19}$F NMR measurements in the normal state of as-grown LaO$_{0.5}$F$_{0.5}$BiS$_2$. The magnetization is dominated by a temperature-independent diamagnetic component and a field- and temperature-dependent paramagnetic contribution $M_\mu(H,T)$ from a $\sim$1000~ppm concentration of local moments, an order of magnitude higher than can be accounted for by measured rare-earth impurity concentrations. $M_\mu(H,T)$ can be fit by the Brillouin function $B_J(x)$ or, perhaps more realistically, a two-level $\tanh(x)$ model for magnetic Bi $6p$ ions in defect crystal fields. Both fits require a phenomenological Curie-Weiss argument $x = \mu_\mathrm{eff}H/(T + T_W)$, $T_W \approx 1.7$ K. There is no evidence for magnetic order down to 2 K, and the origin of $T_W$ is not clear. $^{19}$F frequency shifts, linewidths, and spin-lattice relaxation rates are consistent with purely dipolar $^{19}$F/defect-spin interactions. The defect-spin correlation time $\tau_c(T)$ obtained from $^{19}$F spin-lattice relaxation rates obeys the Korringa relation $\tau_cT = \text{const.}$, indicating the relaxation is dominated by conduction-band fluctuations., Comment: Corrected citations, 15 pages, 15 figures, 6 tables, 69 references, corresponding author O. O. Bernal: obernal@calstatela.edu

Recent Angle-Resolved Photo-emission Spectroscopy (ARPES) experiments [Phys. Rev. Lett. 130, 046402 (2023)] on PdTe, a 3D-Dirac semimetal and a superconductor with the transition temperature Tc ~ 4.3 K, have revealed compelling evidence of the presence of bulk nodes in the superconducting order parameter. To investigate the validity of this proposition, here we present a detailed investigation of the magnetic field dependence of the specific heat of PdTe down to temperatures ~ 58 mK. We observed that the low temperature specific heat of PdTe with an externally applied magnetic field exhibits a power-law field dependence, a characteristic of unconventional superconductivity. Furthermore, the zero-field low-temperature electronic specific heat follows a cubic temperature dependence, which is a signature of the presence of bulk point nodes in PdTe. These intriguing observations suggest that PdTe is a rare and fascinating topological material that exhibits both Dirac semimetallic properties and superconductivity with point nodal gap symmetry., Comment: 7 pages, 3 figures

We report on the origin of spin freezing in the disordered fluorite Ho$_2$Zr$_2$O$_7$. The system is investigated by low-temperature heat capacity as well as by DC and AC magnetization. While the system does not show a long-range magnetic order down to at least $T = 280$~mK, we observe signatures of slow spin dynamics, magnetic field induced relaxation processes at relatively high temperatures, and a spin-frozen state below $T = 0.6$~K. Our results suggest that similar to the canonical spin ice systems Ho$_2$Ti$_2$O$_7$ [Ehlers 2004] and Dy$_2$Ti$_2$O$_7$ [Snyder 2001], spin freezing in Ho$_2$Zr$_2$O$_7$ is preceded by two slow spin relaxation processes; the first forms a field-induced region extending to at least 18~K and the second is rather field-independent and appears at $T_{\mathrm g2} = 1$~K [Ramon 2020].

We explore the magnetotransport and thermoelectric (Seebeck and Nernst coefficients) properties of Mn3SnC an antiperovskite magnetic Nodal line semimetal. Mn3SnC shows paramagnetic (PM) to concurrent antiferromagnetic (AFM)/ferromagnetic (FM) transition at 286 K. The electrical resistivity and Seebeck coefficient indicate the importance of electron magnon scattering in the concurrent AFM/FM regime. We observed a large positive magnetoresistance (MR) of 8.2 at 8 T field near magnetic transition, in the otherwise negative MR behaviour for low temperatures. The electrical resistivity and MR show a weak thermal hysteresis around the boundary of transition temperature and the width of hysteresis decreases as magnetic field increases. Interestingly the Hall and Seebeck coefficients change sign from positive to negative below the transition temperature, highlighting the different scattering for holes and electrons in this multi-band system. The Seebeck and Nernst signal exhibit two sharp anomalies; one at the transition temperature and another at 50 K. The anomaly at magnetic transition in the Nernst signal disappear at 8 T magnetic field, owing to the reduction of magnetic fluctuation. A pseudo-gap near the Fermi level produces an upturn with a broad minimum in the Seebeck signal., Comment: 8 Pages, 5 figures

SBND is the near detector of the Short-Baseline Neutrino program at Fermilab. Its location near to the Booster Neutrino Beam source and relatively large mass will allow the study of neutrino interactions on argon with unprecedented statistics. This paper describes the expected performance of the SBND photon detection system, using a simulated sample of beam neutrinos and cosmogenic particles. Its design is a dual readout concept combining a system of 120 photomultiplier tubes, used for triggering, with a system of 192 X-ARAPUCA devices, located behind the anode wire planes. Furthermore, covering the cathode plane with highly-reflective panels coated with a wavelength-shifting compound recovers part of the light emitted towards the cathode, where no optical detectors exist. We show how this new design provides a high light yield and a more uniform detection efficiency, an excellent timing resolution and an independent 3D-position reconstruction using only the scintillation light. Finally, the whole reconstruction chain is applied to recover the temporal structure of the beam spill, which is resolved with a resolution on the order of nanoseconds., Comment: 21 pages, 17 figures

1T-VSe$_2$ is a narrow band transition metal chalcogenide that shows charge density wave (CDW) state below $T_{CDW}$ = 110 K. Here, we have explored the relevance of Kohler's rule and the thermal transport properties of VSe$_2$ across the CDW state. The magnetoresistance (MR) follows Kohler's rule above $T_{CDW}$, while an extended Kohler's rule is employed below $T_{CDW}$. Interestingly, we observed an anomaly in MR at T = 20 K, below which MR value decreases on lowering temperature. This anomaly is also reflected in the slope ($\kappa$) of Kohler's plots and the relative change in the thermal excitation induced carrier density ($n_T$) also. The $T_{CDW}$ remains largely unaffected in both electrical resistivity ($\rho(T)$) and longitudinal Seebeck coefficient ($\it{S_{xx}}$) even under a strong magnetic field of 14 Tesla. However, the application of magnetic field enhances the peak intensity of $\it{S_{xx}}$ at T $\sim$ 60 K. Additionally, $\it{S_{xx}(T)}$ curves measured at different fields exhibit a crossover at T = 20 K, which suggest the existence of unique feature in the CDW state of VSe$_2$ \textit{i.e.} a locally exact isosbestic point., Comment: 10 pages, 5 figures

We report simultaneous detection of twin kHz and $\sim 40$ Hz quasi-periodic oscillations (QPOs) in the time-resolved analysis of the AstroSat/LAXPC observation of the neutron star low mass X-ray binary, 4U 1728-34. The frequencies of the multiple sets of triplets are correlated with each other and are consistent with their identification as the orbital, periastron and twice the nodal precessions frequencies. The observed relations, along with the known spin of the neutron star, put constraints on the mass and the ratio of moment of inertia to the mass of the neutron star to be $M^*_\odot = 1.92\pm 0.01$ and $I_{45}/M^*_\odot = 1.07\pm 0.01$ under the simplistic assumption that the metric is a Kerr one. We crudely estimate that the mass and moment of inertia values obtained may differ by about 1 % and 5 %, respectively, if a self-consistent metric is invoked. Using the TOV equations for computing the moment of inertia of a neutron star in slow rotation approximation, having different equations of state, we find that the predicted values of neutron star parameters favor stiffer equations of state. We expect more stringent constraints would be obtained using a more detailed treatment, where the EOS-dependent metric is used to compute the expected frequencies rather than the Kerr metric used here. The results provide insight into both the nature of these QPOs and the neutron star interior., Comment: 12 pages, 9 figures, accepted for publication in ApJ

We conducted a photometric and kinematic analysis of the young open cluster NGC 2345 using CCD \emph{UBV} data from 2-m Himalayan Chandra Telescope (HCT), \emph{Gaia} Data Release 3 (DR3), 2MASS, and the APASS datasets. We found 1732 most probable cluster members with membership probability higher than 70$\%$. The fundamental and structural parameters of the cluster are determined based on the cluster members. The mean proper motion of the cluster is estimated to be $\mu_{\alpha}cos\delta$ = ${-1.34}\pm0.20$ and $\mu_{\delta}$= $1.35\pm 0.21$ mas $yr^{-1}$. Based on the radial density profile, the estimated radius is $\sim$ 12.8 arcmin (10.37 pc). Using color-color and color-magnitude diagrams, we estimate the reddening, age, and distance to be $0.63\pm0.04$ mag, 63 $\pm$ 8 Myr, and 2.78 $\pm$ 0.78 kpc, respectively. The mass function slope for main-sequence stars is determined as $1.2\pm 0.1$. The mass function slope in the core, halo, and overall region indicates a possible hint of mass segregation. The cluster's dynamical relaxation time is 177.6 Myr, meaning ongoing mass segregation, with complete equilibrium expected in 100-110 Myr. Apex coordinates are determined as $-40^{\circ}.89 \pm 0.12, -44^{\circ}.99 \pm 0.15$. The cluster's orbit in the Galaxy suggests early dissociation in field stars due to its close proximity to the Galactic disk., Comment: Accepted for publication in A&A and 21 pages, 22 Figures

We present the study of four FUV stars in the field of open cluster NGC 2420 using the Ultra Violet Imaging Telescope (UVIT) mounted on AstroSat. The three stars 525, 527, and 560 are members, while star 646 is a non-member of the cluster. To characterize and determine the parameters of these stars, multi-wavelength spectral energy distributions (SEDs) are analyzed using UV, optical, and IR data sets. For all four FUV bright stars, a two-component SED model fits well. Our findings indicate that two stars, 525 and 560, are binary BSS systems. These binary BSS systems may have formed in a tertiary system due to mass transfer from an evolved outer tertiary companion. Star 527 is a binary system of a BSS and an extremely low-mass (ELM) white dwarf, while Star 646 is a binary system of a horizontal branch star and an ELM white dwarf. The effective temperatures, radii, luminosities and masses of the two ELMs are (10250, 11500) K, (0.42, 0.12) Rsun, (1.61, 0.23) Lsun, and (0.186, 0.170) Msun, respectively. The star 527 could be a post-mass transfer system and may have originated through the Case A/B mass transfer process in a low-density environment. The cooling age of the ELMs is < 1 Myr, indicating that they have only recently formed., Comment: Accepted in ApJ, 9 pages, 4 figures, 1 table

Background and Objective: In an in-vivo situation, the tissue near the blood vessels is rich in oxygen supply compared to the one far from blood vessels. Hence, non-uniform oxygen distribution is observed in biological tissues. Our objective is to explore the influence of non-uniform oxygen supply in the development of necrotic core and, also to examine the effects of necrotic core on tumor growth. Methods: The research is processed through a mathematical approach based on the multiphase mathematical model. To simulate the model, a finite difference numerical method based on the Semi-Implicit Method for Pressure-Linked Equations (SIMPLE) algorithm is adopted. Results: The necrotic core starts to form at the boundary of the tumor with lower oxygen concentration from the initial time. Investigations reveal that the position of the necrotic core varies depending on the oxygen supply through the tumor boundary. The results predict asymmetrical tumor growth under unequal oxygen supply at tumor boundaries. Also, it is hinted that a tumor with a larger size of necrotic core grows slowly as compared to a tumor containing a smaller size of necrotic core. Conclusions: The formulated model has the potential to cast the situation of the tumor growth in an in-vivo and in-vitro situations. This study provides an idea about the location and shape of the necrotic core and the impact of the necrotic core on tumor growth. This information will be beneficial to the clinicians and medical practitioners in predicting the stage of the disease.