arXiv subjects

Arindam Das

Publications and source records attributed to Arindam Das.

At least 37 records · Page 2Linked to original sources

arXiv2025

Hunting for heavy $Z^\prime$ with IceCube neutrinos and gravitational waves

In the minimal gauged B-L extension of the Standard Model, we demonstrate that PeV-scale dark matter (DM) and the baryon asymmetry of the Universe (BAU) can be simultaneously explained through the three right-handed neutrinos (RHNs) present in the theory. The DM candidate undergoes decay into light neutrinos, providing an explanation for the observed IceCube events, while the other two RHNs generate the BAU via leptogenesis. The breaking of gauge symmetry gives rise to detectable gravitational waves (GWs) from decaying cosmic strings (CS), making this framework testable at several future GW detectors-despite being beyond the reach of conventional collider experiments due to the extremely weak coupling. The symmetry-breaking scale establishes a connection between particle masses, couplings, and the GW spectrum, offering a unified and predictive scenario.

hep-ph↗

arXiv2025

Testing neutrino mass hierarchy under type-II seesaw scenario in $U(1)_X$ from colliders

The origin of tiny neutrino mass is a long standing unsolved puzzle of the Standard Model (SM), which allows us to consider scenarios beyond the Standard Model (BSM) in a variety of ways. One of them being a gauge extension of the SM may be realized as in the form of an anomaly free, general $U(1)_X$ extension of the SM, where an $SU(2)_L$ triplet scalar with a $U(1)_X$ charge is introduced to have Dirac Yukawa couplings with the SM lepton doublets. Once the triplet scalar developes a Vacuum Expectation Value (VEV), light neutrinos acquire their tiny Majorana masses. Hence, the decay modes of the triplet scalar has a direct connection to the neutrino oscillation data for different neutrino mass hierarchies. After the breaking of the $U(1)_X$ gauge symmetry, a neutral $U(1)_X$ gauge boson $(Z^\prime)$ acquires mass, which interacts differently with the left and right handed SM fermions. Satisfying the recent LHC bounds on the triplet scalar and $Z^\prime$ boson productions, we study the pair production of the triplet scalar at LHC, 100 TeV proton proton collider FCC, $e^-e^+$ and $μ^-μ^+$ colliders followed by its decay into dominant dilepton modes whose flavor structure depend on the neutrino mass hierarchy. Generating the SM backgrounds, we study the possible signal significance of four lepton final states from the triplet scalar pair production. We also compare our results with the purely SM gauge mediated triplet scalar pair production followed by four lepton final states, which could be significant only in $μ^- μ^+$ collider.

hep-ph↗

arXiv2025

Dewetting Dynamics of Unstable Lubricant Impregnated Surfaces in Liquid Environment

This article outlines a thorough stability analysis by means of both theoretical and experimental modeling for Omni-phobic Lubricant Impregnated Surfaces (LIS). The liquid-repellent properties, particularly with regard to water and oil, have gained substantial attention due to their numerous potential applications. The theoretical section of this study focuses on the validation of mathematical models to understand the underlying principles driving the stability of Omni-phobic LIS. Theoretical insights about the interaction of surface texture, chemical composition, impregnated, and ambient liquid properties contribute to a better understanding of the mechanisms that govern stability. A series of experiments were performed to understand better the stability of fabricated Omni-phobic LIS under cyclopentane and water environments, including viscosity and surface texture variations, especially post-spacing variation. The experimental results validate the theoretical predictions and provide valuable statistical information regarding possible model modification. The replaced oil or nucleation sites can be explained through CHNT. The analysis was further validated with experimentally observed nucleation sites. This confirms the accuracy of the nucleation predictions and supports the underlying theoretical model. According to the CLW model, the length of a liquid's penetration into a cylinder/square-shaped capillary is expressed as a square root of time. Our findings contribute to designing a stable LIS and then determining the model followed by an unstable one. The proposed MLW model validated the experimental results. In addition, these experimental data points fit the different capillary imbibition regimes such as inertial, early viscous etc. This contributes to the development of robust and durable solutions for practical applications.

cond-mat.soft↗

arXiv2025

Resonant leptogenesis in minimal $U(1)_X$ extensions of the Standard Model

We investigate a general $U(1)_X$ scenario where we introduce three generations of Standard Model (SM) singlet Right Handed Neutrinos (RHNs) to generate the light neutrino mass through the seesaw mechanism after the breaking of $U(1)_X$ and electroweak symmetries. In addition to that, a general $U(1)_X$ scenario involves an SM-singlet scalar field and due to the $U(1)_X$ symmetry breaking the mass of a neutral beyond the SM (BSM) gauge boson $Z^\prime$ is evolved. The RHNs, being charged under $U(1)_X$ scenario, can explain the origin of observed baryon asymmetry through the resonant leptogenesis process. Applying observed neutrino oscillation data we study $Z^\prime$ and BSM scalar induced processes to reproduce the observed baryon asymmetry. Hence we estimate bounds on the $U(1)_X$ gauge coupling $(g_X)$ and the mass of the $Z^\prime$ $(M_{Z^\prime})$ for different $U(1)_X$ charges and benchmark masses of RHN and SM-singlet scalar. Finally we compare our results with limits obtained from the existing limits from LEP-II and LHC. We find that depending on the $U(1)_X$ charges, the masses of RHNs and SM-singlet scalar resonant leptogenesis could provide stronger limit on $g_X$ for $M_{Z^\prime} > 5.8$ TeV which could be probed by high energy scattering experiment in future.

hep-ph↗

arXiv2025

BEVMOSNet: Multimodal Fusion for BEV Moving Object Segmentation

Accurate motion understanding of the dynamic objects within the scene in bird's-eye-view (BEV) is critical to ensure a reliable obstacle avoidance system and smooth path planning for autonomous vehicles. However, this task has received relatively limited exploration when compared to object detection and segmentation with only a few recent vision-based approaches presenting preliminary findings that significantly deteriorate in low-light, nighttime, and adverse weather conditions such as rain. Conversely, LiDAR and radar sensors remain almost unaffected in these scenarios, and radar provides key velocity information of the objects. Therefore, we introduce BEVMOSNet, to our knowledge, the first end-to-end multimodal fusion leveraging cameras, LiDAR, and radar to precisely predict the moving objects in BEV. In addition, we perform a deeper analysis to find out the optimal strategy for deformable cross-attention-guided sensor fusion for cross-sensor knowledge sharing in BEV. While evaluating BEVMOSNet on the nuScenes dataset, we show an overall improvement in IoU score of 36.59% compared to the vision-based unimodal baseline BEV-MoSeg (Sigatapu et al., 2023), and 2.35% compared to the multimodel SimpleBEV (Harley et al., 2022), extended for the motion segmentation task, establishing this method as the state-of-the-art in BEV motion segmentation.

cs.CV↗

arXiv2025

High Speed Imagery Analysis of Droplet Impact on Soft Oil Infused Surface

Droplet impact on solid liquid-infused surfaces (LIS) has been widely explored due to its significant scientific implications and industrial relevance. In most studies, the predominant impact behavior observed is complete droplet rebound. In This study we investigated the influence of octadecyltrichlorosilane (OTS) functionalization and oil coatings on the droplet impact dynamics of smooth polydimethylsiloxane (PDMS) surfaces. We conducted droplet impact experiments on smooth PDMS functionalized with OTS and subsequently coated or absorbed with two different oils, silicone oil (5cSt) and hexadecane, to create Van der Waals and non-Van der Waals SLIP surfaces. Contact angle measurements revealed that OTS functionalization reduced adhesion and increased water repellency, facilitating partial droplet rebound upon impact. Oil-coated surfaces exhibited reduced droplet spreading due to viscous resistance, while absorbed oils altered surface flexibility, influencing impact dynamics. PDMS samples absorbed with silicone oil demonstrated complete droplet rebound at all Weber numbers, whereas hexadecane-absorbed surfaces exhibited limited spreading and no rebound, highlighting the significance of oil-PDMS interactions. High-speed imaging and quantitative analysis confirmed that surface functionalization and oil interactions critically affect droplet spreading, recoil, and rebound behavior. These findings provide insights into optimizing liquid-repellent surfaces for applications such as self-cleaning coatings and droplet transport systems.

physics.flu-dyn↗

arXiv2024

Reflective Teacher: Semi-Supervised Multimodal 3D Object Detection in Bird's-Eye-View via Uncertainty Measure

Applying pseudo labeling techniques has been found to be advantageous in semi-supervised 3D object detection (SSOD) in Bird's-Eye-View (BEV) for autonomous driving, particularly where labeled data is limited. In the literature, Exponential Moving Average (EMA) has been used for adjustments of the weights of teacher network by the student network. However, the same induces catastrophic forgetting in the teacher network. In this work, we address this issue by introducing a novel concept of Reflective Teacher where the student is trained by both labeled and pseudo labeled data while its knowledge is progressively passed to the teacher through a regularizer to ensure retention of previous knowledge. Additionally, we propose Geometry Aware BEV Fusion (GA-BEVFusion) for efficient alignment of multi-modal BEV features, thus reducing the disparity between the modalities - camera and LiDAR. This helps to map the precise geometric information embedded among LiDAR points reliably with the spatial priors for extraction of semantic information from camera images. Our experiments on the nuScenes and Waymo datasets demonstrate: 1) improved performance over state-of-the-art methods in both fully supervised and semi-supervised settings; 2) Reflective Teacher achieves equivalent performance with only 25% and 22% of labeled data for nuScenes and Waymo datasets respectively, in contrast to other fully supervised methods that utilize the full labeled dataset.

cs.CV↗

arXiv2024

Probing chiral and flavored $Z^\prime$ from cosmic bursts through neutrino interactions

The origin of tiny neutrino mass is an unsolved puzzle leading to a variety of phenomenological aspects beyond the Standard Model (BSM). We consider $U(1)$ gauge extension of the Standard Model (SM) where so-called seesaw mechanism is incarnated with the help of thee generations of Majorana type right-handed neutrinos followed by the breaking of $U(1)$ and electroweak gauge symmetries providing anomaly free structure. In this framework, a neutral BSM gauge boson $Z^\prime$ is evolved. To explore the properties of its interactions we consider chiral (flavored) frameworks where $Z^\prime$ interactions depend on the handedness (generations) of the fermions. In this paper we focus on $Z^\prime-$neutrino interactions which could be probed from cosmic explosions. We consider $ν\overlineν \to e^+ e^-$ process which can energize gamma-ray burst (GRB221009A, so far the highest energy) through energy deposition. Hence estimating these rates we constrain $U(1)$ gauge coupling $(g_X)$ and $Z^\prime$ mass $(M_{Z^\prime})$ under Schwarzchild (Sc) and Hartle-Thorne (HT) scenarios. We also study $ν-$DM scattering through $Z^\prime$ to constrain $g_X-M_{Z^\prime}$ plane using IceCube data considering high energy neutrinos from cosmic blazar (TXS0506+056), active galaxy (NGC1068), the Cosmic Microwave Background (CMB) and the Lyman-$α$ data, respectively. Finally highlighting complementarity we compare our results with current and prospective bounds on $g_X-M_{Z^\prime}$ plane from scattering, beam-dump and $g-2$ experiments.

hep-ph↗

arXiv2024

MapsTP: HD Map Images Based Multimodal Trajectory Prediction for Automated Vehicles

Predicting ego vehicle trajectories remains a critical challenge, especially in urban and dense areas due to the unpredictable behaviours of other vehicles and pedestrians. Multimodal trajectory prediction enhances decision-making by considering multiple possible future trajectories based on diverse sources of environmental data. In this approach, we leverage ResNet-50 to extract image features from high-definition map data and use IMU sensor data to calculate speed, acceleration, and yaw rate. A temporal probabilistic network is employed to compute potential trajectories, selecting the most accurate and highly probable trajectory paths. This method integrates HD map data to improve the robustness and reliability of trajectory predictions for autonomous vehicles.

cs.CV↗

arXiv2024

Dark matter-electron scattering and freeze-in scenarios in the light of $Z^\prime$ mediation

We investigate dark matter (DM)-electron scattering in a minimal $U(1)_X$ extension of the Standard Model (SM), where the DM can appear as a Majorana fermion, a complex singlet scalar or a Dirac fermion. To study bounds on the $U(1)_X$ gauge coupling $(g_X)$ and new gauge boson mass $(M_{Z^\prime})$, from DM-electron scattering, we consider several direct search experiments like CDMS, DAMIC, SENSEI, PandaX-II, DarkSide-50 and XENON1T-S2 for different $U(1)_X$ charges. In this set-up we consider DM production via freeze-in both in radiation dominated and modified cosmological background to project sensitivities on $g_X-M_{Z^\prime}$ plane satisfying observed relic abundance. DM-electron scattering could provide comparable, or even stronger bounds than those obtained from the electron/ muon $(g-2)$, low energy scattering and intensity frontier experiments within 0.01 GeV $\lesssim M_{Z^\prime} \lesssim$ 0.1 GeV. Constrains from freeze-in could provide stronger sensitivities for $M_{Z^\prime}\gtrsim \mathcal{O}(1)$ GeV, however, these limits are comparable to those obtained from LHCb, LEP experiments for $\mathcal{O}(10)$ GeV $\lesssim M_{Z^\prime} \lesssim 150$ GeV. In future, electron-muon scattering (MUonE), proton (FASER, DUNE) and electron/positron (ILC) beam dump experiments could probe these parameters.

hep-ph↗

arXiv2024

Experimental Insights into Droplet Behavior on Van der Waals and Non-Van der Waals Liquid-Impregnated Surfaces

Droplet impact is a fascinating phenomenon that occurs when a liquid droplet collides with a surface. It is not only a fundamental area of scientific inquiry but also has practical implications across many industries and natural systems. The dynamics during droplet impact on liquid-impregnated surfaces are of special interest because the properties of the surface and impregnated liquid may significantly change the impact outcome. We present a detailed study of the impact and subsequent retraction of liquid droplets on a liquid-impregnated surface using high-speed imagery. Square-shaped textures with varying post-spacings of 5, 20, and 30 um on a silicon wafer were fabricated and functionalised using octadecyl trichlorosilane. Two different lubricants, silicone oil and hexadecane, were infused to investigate how their properties affect impact dynamics. Droplet impacts were investigated on these surfaces across a broad range of Weber numbers (28-495). Additionally, we measured the stability of the LIS surface by calculating spreading coefficients and contact angles. The experiments revealed that the properties of the infused oil play an insignificant role in droplet dynamics, including spreading, rebound, and unique phenomena related to oil interaction with surface textures. This study provides insights into the intricate dynamics of droplet interactions with LIS, offering valuable contributions to understanding surface-wetting phenomena.

physics.flu-dyn↗

arXiv2024

Enhancement of the Higgs decay into a $Z^\prime$ pair in models with $U(1)_X$ gauge symmetry

We discuss the Higgs phenomenology in models with a new $U(1)_X$ gauge symmetry including the $U(1)_{B-L}$ scenario, where three right-handed neutrinos are inevitably introduced due to the gauge anomaly cancellations. We find that the decay branching ratio of the discovered Higgs boson into a pair of new massive gauge bosons ($Z'$) can significantly be enhanced in the Dirac neutrino case as compared with the Majorana case for a fixed value of the new gauge coupling and the mass of $Z'$ under constraints from current experimental data. Because of such an enhancement, the Dirac case can indirectly be discriminated from the Majorana case via the Higgs decay.

hep-ph↗

arXiv2024

Freeze-in production of sterile neutrino dark matter in a gauged U$(1)^\prime$ model with inverse seesaw

We consider a general, anomaly free U$(1)^\prime$ extension of the Standard Model (SM) where the neutrino mass is generated at the tree level via the inverse seesaw mechanism. The model contains three right handed neutrinos, three additional singlet fermions, one extra complex scalar and a neutral gauge boson $(Z^\prime)$. Instead of resorting to a specific $U(1)$ extension, we consider a class of models by taking the $U(1)^\prime$ charges of the scalars to be free parameters. Here, we assign one pair of the pseudo-Dirac degenerate sterile neutrinos as Dark Matter (DM) candidates which are produced by the freeze-in mechanism. Considering different mass regimes of the DM, $Z^\prime$ and reheating temperature, we obtain constraints on the $U(1)^\prime$ charges giving the correct relic abundance. We have also obtained constraints on $Z^\prime$ mass and coupling from consideration of relic density as well as high energy collider experiments like ATLAS in case of heavy $Z^\prime$ or in intensity and lifetime frontier experiments like DUNE, FASERs, and ILC beam dump which are looking for light $Z^\prime$. Additionally, in this model, the decay of pseudo-Dirac DM into active neutrinos can explain the 511 keV line observed by the INTEGRAL satellite.

hep-ph↗

arXiv2024

$Z^\prime$ induced forward dominant processes in $μ$TRISTAN experiment

General $U(1)$ extension of the Standard Model (SM) is a well motivated beyond the Standard Model(BSM) scenario where three generations of right handed neutrinos (RHNs) are introduced to cancel gauge and mixed gauge-gravity anomalies. After the $U(1)_X$ is broken, RHNs participate in the seesaw mechanism to generate light neutrino masses satisfying neutrino oscillation data. In addition to that, a neutral gauge boson $Z^\prime$ is evolved which interacts with the left and right handed fermions differently manifesting chiral nature of the model which could be probed in future collider experiments. As a result, if we consider $μ^+ e^-$ and $μ^+ μ^+$ collisions in $μ$TRISTAN experiment $Z^\prime$ mediated $2\to2$ scattering will appear in $t-$ and $u-$channels depending on the initial and final states being accompanied by the photon and $Z$ mediated interactions. This will result well motivated resulting forward dominant scenarios giving rise to sizable left-right asymmetry. Estimating constrains on general $U(1)$ coupling from LEP-II and LHC for different $U(1)_X$ charges, we calculate differential and integrated scattering cross section and left-right asymmetry for $μ^+ e^- \to μ^+ e^-$ and $μ^+ μ^+ \to μ^+ μ^+$ processes which could be probed at $μ$TRISTAN experiment further enlightening the interaction between $Z^\prime$ and charged leptons and the $U(1)_X$ breaking scale.

hep-ph↗

arXiv2024

Probing for chiral $Z^\prime$ gauge boson through scattering measurement experiments

Motivated by the observation of tiny neutrino mass can not be explained within the framework of Standard Model (SM), we consider extra gauge extended scenarios in which tiny neutrino masses are generated through seesaw mechanism. These scenarios are equipped with beyond the standard model (BSM) neutral gauge boson called $Z^\prime$ in the general $U(1)_X$ symmetry which is a linear combination of $U(1)_Y$ and $U(1)_{B-L}$. In this case, left and right handed fermions interact differently with the $Z^\prime$. The $Z^\prime$ gives rise to different processes involving neutrino-nucleon, neutrino-electron, electron-nucleus and electron-muon scattering processes. By comparing with proton, electron beam-dump experiments data, recast data from searches for the long-lived and dark photon at BaBaR, LHCb and CMS experiments, the electron and muon $g-2$ data, and the data of the dilepton and dijet searches at the LEP experiment, we derive bounds on the gauge coupling and the corresponding gauge boson mass for different $U(1)_X$ charges and evaluate the prospective limits from the future beam-dump scenarios at DUNE, FASER(2) and ILC. We conclude that large parameter regions could be probed by scattering, beam-dump and collider experiments in future.

hep-ph↗

arXiv2024

Fisheye Camera and Ultrasonic Sensor Fusion For Near-Field Obstacle Perception in Bird's-Eye-View

Accurate obstacle identification represents a fundamental challenge within the scope of near-field perception for autonomous driving. Conventionally, fisheye cameras are frequently employed for comprehensive surround-view perception, including rear-view obstacle localization. However, the performance of such cameras can significantly deteriorate in low-light conditions, during nighttime, or when subjected to intense sun glare. Conversely, cost-effective sensors like ultrasonic sensors remain largely unaffected under these conditions. Therefore, we present, to our knowledge, the first end-to-end multimodal fusion model tailored for efficient obstacle perception in a bird's-eye-view (BEV) perspective, utilizing fisheye cameras and ultrasonic sensors. Initially, ResNeXt-50 is employed as a set of unimodal encoders to extract features specific to each modality. Subsequently, the feature space associated with the visible spectrum undergoes transformation into BEV. The fusion of these two modalities is facilitated via concatenation. At the same time, the ultrasonic spectrum-based unimodal feature maps pass through content-aware dilated convolution, applied to mitigate the sensor misalignment between two sensors in the fused feature space. Finally, the fused features are utilized by a two-stage semantic occupancy decoder to generate grid-wise predictions for precise obstacle perception. We conduct a systematic investigation to determine the optimal strategy for multimodal fusion of both sensors. We provide insights into our dataset creation procedures, annotation guidelines, and perform a thorough data analysis to ensure adequate coverage of all scenarios. When applied to our dataset, the experimental results underscore the robustness and effectiveness of our proposed multimodal fusion approach.

cs.CV↗

arXiv2023

BEVSeg2TP: Surround View Camera Bird's-Eye-View Based Joint Vehicle Segmentation and Ego Vehicle Trajectory Prediction

Trajectory prediction is, naturally, a key task for vehicle autonomy. While the number of traffic rules is limited, the combinations and uncertainties associated with each agent's behaviour in real-world scenarios are nearly impossible to encode. Consequently, there is a growing interest in learning-based trajectory prediction. The proposed method in this paper predicts trajectories by considering perception and trajectory prediction as a unified system. In considering them as unified tasks, we show that there is the potential to improve the performance of perception. To achieve these goals, we present BEVSeg2TP - a surround-view camera bird's-eye-view-based joint vehicle segmentation and ego vehicle trajectory prediction system for autonomous vehicles. The proposed system uses a network trained on multiple camera views. The images are transformed using several deep learning techniques to perform semantic segmentation of objects, including other vehicles, in the scene. The segmentation outputs are fused across the camera views to obtain a comprehensive representation of the surrounding vehicles from the bird's-eye-view perspective. The system further predicts the future trajectory of the ego vehicle using a spatiotemporal probabilistic network (STPN) to optimize trajectory prediction. This network leverages information from encoder-decoder transformers and joint vehicle segmentation.

cs.CV↗

arXiv2023

Design and Fabrication of Industrially Scalable low cost Liquid Impregnated Surfaces with extreme hydratephobic properties

The design and fabrication of extremely hydrate phobic Liquid Impregnated Surfaces (sometimes abbreviated as LIS) based on industrial material Aluminium Al6061 and industrially scalable low-cost method were carried out. A simple hydrochloric acid-based etching method and boiling water treatment were used to generate micro and nanoscale nanopetal roughness features respectably. A theoretical analysis was performed to find out the relationship between the interfacial interactions and surface roughness features to predict the stability of lubricant oil of LIS under water and oil environment. LIS with appropriate surface chemistry and textures were fabricated to experimentally validate the theoretical analysis on lubricant stability. Subsequent experimental measurements of hydrate adhesion were performed on LIS with stable lubricant layers, using a custom-made experimental setup and cantilever-based method. Cyclopentane hydrate, mimics gas hydrate forming mechanism at atmospheric pressure, and is used for the hydrate adhesion measurements. Extreme reduction of hydrate adhesion with more than four orders of magnitude was observed on LIS compared to control smooth aluminium surfaces

physics.flu-dyn↗