arXiv subjects

Poshak Gandhi

Publications and source records attributed to Poshak Gandhi.

At least 19 recordsLinked to original sources

arXiv2026

GATOS XV: A JWST/MIRI survey of extended circumnuclear dust emission in nearby Seyfert galaxies

The subarcsecond angular resolution and stable background of JWST has given us the first high-fidelity images of the arcsecond-scale environment around Active Galactic Nuclei (AGNs) in the nearby Universe. With mid-infrared (MIR) surface brightness sensitivities that are much deeper than the best ground-based instruments, the Mid-InfraRed Instrument imager (MIRIM) now allows us to understand the structure and thermal properties of dust using information over wavelengths of $5$-$25$ $μ$m, almost all of the MIR range. We present a Cycle 1 JWST MIRIM survey of Seyfert galaxies with the express aim of characterising AGN-heated dust in the central few 100 pcs, and searching for signatures of dust-laden nuclear outflows. This paper outlines the motivation behind the programme, the data reduction and analysis techniques used to isolate the nuclear and extended emission, and a comparison of the observed MIR structures with those seen in other phases (stars, ionised and molecular gas, absorbing dust). In concert with earlier studies that used these data, we conclude that resolved AGN-heated dust is widespread in the Seyfert population, extending out to a few hundred pcs from the nucleus and often displaying a higher surface-brightness compared to the more widespread star-forming dusty circumnuclear disk. Even after accounting for contamination from emission lines in the MIRI filters, we find strong spatial correlations between MIR dust emission and the AGN-ionised gas in the narrow-line region (NLR).

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arXiv2026

Galactic Science with Ultra-High Angular Resolution X-ray Imaging

Milli- to micro-arcsecond X-ray imaging will open a new observational regime for Galactic astrophysics by resolving physical scales that are inaccessible to current X-ray observatories. This white paper highlights the science enabled by such capabilities across four broad questions: how particles are accelerated, how stars die, how accretion is fueled, and what populations of X-ray sources inhabit the Galaxy. Ultra-high angular resolution will enable many new studies, such as resolving shocks and jets, measuring proper motions, parallaxes, and binary orbits, and providing secure multiwavelength counterpart identifications in crowded environments such as the Galactic Center and globular clusters. Combined with high-time-resolution observations, these measurements will connect variability and transient events to the physical structures in which they originate, while coordination with gravitational-wave, neutrino, $γ$-ray, radio, optical, and infrared facilities will provide spatial information needed to identify and characterize multi-messenger sources. In addition to defining the science cases, this paper presents a curated list of compelling targets spanning various angular resolutions and outlines the complementary specifications necessary to maximize the scientific outcome. Accomplishing these science goals will require an instrument with high angular resolution, precise astrometry, substantial collecting area, sufficient spectral and timing resolution, and high dynamic range imaging capabilities.

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arXiv2026

XRISM Resolves the Circum-nuclear Environment of NGC 4945

Compton-thick Active Galactic Nuclei (AGN) represent one of the most elusive phases of massive black hole growth, yet are expected to contribute substantially to the Cosmic X-ray Background and the integrated growth of massive black holes. NGC 4945 is the closest Compton-thick AGN and amongst the brightest AGN in the hard X-ray sky, making it an important benchmark for more distant Compton-thick AGN. We present the first high-resolution X-ray spectral analysis of NGC 4945 using XRISM/Resolve. The entire 4-15 keV Resolve spectrum, including a strong Fe K$α$ doublet and weak Compton Shoulder, is well described by a de-coupled dual-obscurer model. The model features a low-covering-factor Compton-thick primary obscurer intersecting the line-of-sight that permits the rapidly variable, direct transmitted coronal continuum to dominate above 10 keV. A Compton-thin secondary reprocessor with a high covering factor dominates the reprocessed emission between $\sim$4-10 keV. Assuming that virial motion accounts for line broadening, the secondary reprocessor can exist at $\sim$0.12 pc, and could help explain the weak high-ionisation optical and infrared emission lines observed in NGC 4945. If such obscuration geometries are common among more distant and/or fainter Compton-thick AGN, our results suggest that simpler coupled X-ray spectral modelling could substantially over-estimate Compton-thick covering factors and under-estimate intrinsic X-ray luminosities.

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arXiv2026

Energy-dependent Optical/Near-infrared and X-ray Correlations in Swift J1727.8-1613

We present a timing analysis of the black hole transient Swift J1727.8-1613 during its intermediate state. We use coordinated broadband X-ray observations from Insight-HXMT (2-150 keV), together with optical data from ULTRACAM (g_s and i_s bands) and near-infrared data from HAWK-I (K_s band), obtained on 2023 September 9. As shown by previous studies, the Fourier power spectrum shows a strong quasi-periodic oscillation (QPO) in the K_s, i_s and X-ray bands. Cross-correlation analysis reveals a complex coupling between the optical/near-infrared (OIR) and X-ray emission, including a delayed optical anti-correlation, a strong infrared correlation, and a pronounced dependence of these features on X-ray energy, suggesting multiple Comptonisation regions. In contrast, the lag properties do not change at the QPO frequency, displaying an OIR lag of ~60-80 ms up to 150 keV. We discuss these results in the context of small-scale jet and hot accretion flow scenarios.

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arXiv2026

Optical Counterparts to X-ray sources in LSST DP1

We present a crossmatch between a combined catalog of X-ray sources and the Vera C. Rubin Observatory Data Preview 1 (DP1) to identify optical counterparts. The six fields targeted as part of DP1 include the Extended Chandra Deep Field South (E-CDF-S), the Euclid Deep Field South (EDF-S), the Fornax Dwarf Spheroidal Galaxy (Fornax dSph), 47 Tucanae (47 Tuc) and science validation fields with low galactic and ecliptic latitude (SV\_95\_-25 and SV\_38\_7, respectively). We find matches to 2314 of 3830 X-ray sources. We also compare our crossmatch to DP1 in the E-CDF-S field to previous efforts to identify optical counterparts. The probability of a chance coincidence match varies across each DP1 field, with overall high reliability in the E-CDF-S field, and lower proportion of high-reliability matches in the other fields. The majority of previously known sources that we detect are, unsurprisingly, active galaxies. We plot the X-ray-to-optical flux ratio against optical magnitude and color in an effort to identify Galactic accreting compact objects using a {\em Gaia} color threshold transformed to LSST $g$--$i$, but do not find any strong candidates in these primarily extragalactic counterparts. The DP1 dataset contains high-cadence photometry collected over a number of nights. We calculate the Stetson $ J $ variability index for each object under the hypothesis that X-ray counterparts tend to exhibit higher optical variability; however, the evidence is inconclusive whether our sample is more variable over DP1 timescales when compared to field objects.

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arXiv2026

An intrinsic decline of accretion activity in GRS 1915+105

The canonical microquasar GRS 1915+105 is exhibiting unprecedented changes in its multiwavelength properties since 2018. Recent pointed observations with NuSTAR in November 2025 have failed to detect the source at flux limits several orders of magnitude deeper than historical X-ray levels. Under an enhanced obscuration scenario, the absence of hard X-rays requires that any obscuring cocoon must be deeply Compton-thick and fully sky covering, with a stringent limit on scattering fractions being less than 1 part in >~10^4, if intrinsic accretion activity continues unabated. An ionised cocoon could also account for a deep radio non-detection in June 2026. But such an interpretation is in conflict with mid-infrared fading of the source observed with SPHEREx in September 2025 and then again in April/May 2026. These facts, together with the source location in the infrared vs. X-ray plane, are consistent with an intrinsic weakening of accretion activity around November 2025 or earlier. We propose that outflows witnessed during intense multiwavelength flaring in 2023-2024 have progressively expelled fueling material from the inner disc, resulting in a significant drop in accretion activity. If correct, the current state gives unique insight into ongoing dramatic secular accretion changes on human timescales. High-frequency resolved radio observations and sensitive infrared or sub-mm observations could test this scenario, and characterise any gaseous cocoon still veiling the source.

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arXiv2026

GATOS XIV: The first direct kinematic evidence of dusty outflows from AGN via PAH kinematics of local Seyfert galaxies with JWST

We present the first spatially resolved kinematic evidence for dust in the outflows of Active Galactic Nuclei (AGN). We utilise observations from JWST with NIRSpec IFU and MIRI MRS data of 10 local Seyferts and use Principal Component Analysis (PCA) tomography to extract the kinematics of Polycyclic Aromatic Hydrocarbon (PAH) features. PAHs comprise the smallest carbonaceous dust molecules in the Interstellar Medium (ISM), and produce emission features in the infrared providing the potential to measure kinematics. This is however challenging due to their broad shapes and variations in their intrinsic profile, prompting the need for techniques such as PCA tomography. We find that the velocity of the PAHs is similar to the molecular gas as traced by the rotational transitions of H$_2$, where for NGC 5728 and NGC 7582, both disk and outflow are present. We detect the outflow in the kinematics of large and neutral PAHs, namely the 11.3 $μ$m and 17 $μ$m PAH features, where after subtracting the disk, the velocity field matches that of high-ionisation potential lines such as [NeVI] (7.65 $μ$m, IP = 158 eV). Finally, we fail to detect kinematics of the 6.2 $μ$m PAH due to an altered intrinsic profile while the the 3.3 $μ$m PAH kinematics purely trace the circumnuclear disk. This suggests the PAHs in the outflow are more neutral and larger than in star-forming regions, consistent with PAH band ratios in previous studies of AGN.

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arXiv2026

GATOS XI : Excess dust heating in the Narrow Line Regions of nearby AGN revealed with JWST/MIRI

We present JWST/MIRI imaging of eight nearby Active Galactic Nuclei (AGN) from the GATOS survey to investigate the physical conditions of extended dust in their narrow line regions (NLRs). In four galaxies (ESO 428-G14, NGC 4388, NGC 3081, and NGC 5728), we detect spatially resolved dust structures extending ~100-200 pc along the NLR. In these systems, we find a strong link between the morphology of the dust, the radio ejecta, and the coronal [Si VI] emission, implying that dust carries imprints of the processes shaping the NLR. Using spatially resolved spectral energy distributions, we show that dust in the NLR has systematically steeper slopes than star forming clumps. This dust emits at temperatures in the range 150 - 220 K, at a distance of ~150 pc from the nucleus. Using simple models, we show that, even under optimistic assumptions of grain size and AGN luminosity, the excess MIR emission cannot be explained by AGN illumination alone. We interpret this excess heating as in-situ. We show that shocks with velocities of $v_{\rm shock} \sim 200- 400 \, \rm km/s$ in dense gas can close this gap, and in some cases even account for the total observed emission. This, combined with multiple lines of evidence for shocks in these regions, supports a scenario in which shocks not only coexist with dust but may be playing a key role in heating it. Our findings reveal shocks may be an important and previously overlooked driver of extended dust emission in the central hundreds of parsecs in AGN.

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arXiv2026

A comprehensive search for high-velocity X-ray sources: New compact object binary candidates in the Gaia era

We perform a comprehensive search for high-velocity X-ray sources with large X-ray/optical flux ratios ($F_\mathrm{X}/F_\mathrm{G}$), identifying candidates for interacting black hole or neutron star binaries potentially accelerated by supernova natal kicks. We cross-match X-ray points sources from a variety of catalogues (Chandra, XMM-Newton, Swift and eROSITA) with Gaia DR3. Using Gaia coordinates, parallaxes, and proper motions, we compute peculiar velocities ($\upsilon_\mathrm{pec}$) relative to Galactic disc rotation. Remaining agnostic about radial velocities (RVs), we vary RVs to find the minimum possible $\upsilon_\mathrm{pec}$ values ($\upsilon_\mathrm{pec, min}$). Uncertainties on $\upsilon_\mathrm{pec, min}$ are estimated via Monte Carlo resampling, and we select X-ray sources that have $1\,σ$ lower limits on $\upsilon_\mathrm{pec, min}\geq 200\,\mathrm{km~s^{-1}}$ and high $F_\mathrm{X}/F_\mathrm{G}$ values. We show that this velocity threshold excludes most contaminants (e.g., cataclysmic variables and active binaries) while retaining a sensible fraction of compact object binaries, demonstrating that $\upsilon_\mathrm{pec}$ could serve as an effective indicator for the presence of a neutron star or black hole companion. Our selection yields a sample of 2372 sources, from which we construct a gold sample of 7 sources that have relatively well-constrained astrometry and confident optical counterparts. Follow-up is necessary to confirm and characterise their high-energy emission, as well as a Galactic disc vs. halo origin.

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arXiv2025

XRISM Spectroscopy of the Stellar-mass Black Hole GRS 1915+105

GRS 1915$+$105 was the stellar-mass black hole that best reproduced key phenomena that are also observed in Type-1 active galactic nuclei. In recent years, however, it has evolved to resemble a Type-2 or Compton-thick AGN. Herein, we report on the first XRISM observation of GRS 1915$+$105. The high-resolution Resolve calorimeter spectrum reveals that a sub-Eddington central engine is covered by a layer of warm, Compton-thick gas. With the obscuration acting as a coronagraph, numerous strong, narrow emission lines from He-like and H-like charge states of Si, S, Ar, Ca, Cr, Mn, Fe, and Ni dominate the spectrum. Radiative recombination continuum (RRC) features are also observed, signaling that much of the emitting gas is photoionized. The line spectrum can be fit by three photoionized emission zones, with broadening and bulk velocities suggestive of an origin in the outer disk atmosphere and/or a slow wind at $r \simeq 10^{6}~GM/c^{2}$. The Fe XXV He-$α$ and Fe XXVI Ly-$α$ lines have a broad base that may indicate some emission from $r \sim 3\times 10^{3}~GM/c^{2}$. These results broadly support a picture wherein the current state in GRS 1915$+$105 is due to obscuration by the irradiated outer disk. This could arise through disk thickening if the Eddington fraction is higher than inferred, but it is more likely due to a warped, precessing disk that has brought the outer disk into the line of sight. We discuss the strengths and weaknesses of this interpretation and our modeling, and possible explanations of some potentially novel spectral features.

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arXiv2025

GATOS. VIII. On the physical origin of the extended MIR emission in AGN

The polar mid-infrared (MIR) emission detected within 10-100s pcs in some active galactic nuclei (AGN) has been associated with dusty winds driven away by radiation pressure. The physical characterization of this extended polar emission remains uncertain. Here we combine 10-21 $μ$m JWST/MIRI imaging observations with 7-25 $μ$m JWST/MRS integral field spectroscopic observations of 6 nearby, $\bar{D}=35.4\pm4.6$ Mpc, AGN from the GATOS Survey to quantify the nature of the extended MIR emission at ~75 pc resolution at 21 $μ$m. These AGN have similar bolometric luminosities, $\log_{10}(\bar{L}_{bol}\,[erg\,s^{-1}])=44.0\pm0.3$, span a wide range of optical outflow rates, $\dot{M}=0.003-0.21$ M$_{\odot}$ yr$^{-1}$, column densities, $\log_{10}(N_{H}^{X-ray}[cm^{-2}])=22.2-24.3$, and Eddington ratios, $λ_{Edd}=0.005-0.06$. We cross-correlate the line-only and continuum-only images and find a poor correlation, which indicates that the extended MIR continuum emission is spatially uncorrelated with the warm outflows associated with narrow emission lines within 10-15 $μ$m. Line emission is resolved along the jet axis, while dust emission is perpendicular to it. The 75-450 pc continuum emission has a fairly constant dust temperature, $T_{d}=132^{+7}_{-7}$ K, and mass, $M_{d}=728^{+29}_{-27}$ M$_{\odot}$. Using the conditions of energy balance between radiation-pressure and gravity ($λ_{Edd}$ vs. N$_{H}$), we find that our AGN sample is in the gravitationally bounded regime consistent with no detection of dusty winds. At 10 $μ$m, the level of extended line emission contribution is correlated with the outflow kinetic energy and mass outflow rates. We find no correlation with the AGN properties. These results indicate that the radio jet may be triggering the gas outflow and line emission, while the extended dust emission is distributed in molecular clouds and/or shocked regions.

astro-ph.GA↗

arXiv2025

Further evidence for natal kick segregation by spectral type in high-mass X-ray binaries

High-mass X-ray binaries (HMXBs) are systems in which a neutron star or black hole accretes material from a massive companion. HMXBs are expected to have experienced a supernova in their evolution. The impulsive kick associated with this event should affect the space velocity of the system in a way that depends on the nature and state of the progenitor binary. Here, we test whether the different evolutionary histories of HMXBs have left a detectable imprint on their peculiar velocities ($V_{\rm pec}$). Using data from Gaia Data Release 3 (Gaia DR3), we first calculate the $V_{\rm pec}$ values for 63 well-known HMXBs hosting a black hole or neutron star and estimate the associated uncertainties via Monte Carlo re-sampling. We then analyse their distribution and check for differences between classes. Overall, $V_{\rm pec}$ estimates extend up to 100 km s$^{-1}$, but with Be/X-ray binaries (BeXRBs) favouring $V_{\rm pec}$ $\lesssim 40$ km s$^{-1}$ and supergiant X-ray binaries (SgXRBs) favouring $V_{\rm pec}$ $\gtrsim 40$ km s$^{-1}$. Based on a Kolmogorov-Smirnov (K-S) test, the null hypothesis that the peculiar velocities of both classes are drawn from the same parent distribution can be robustly rejected, irrespective of the background stellar velocity dispersion. Tests with binary population synthesis demonstrate that SgXRBs typically have shorter orbital periods and higher fractional mass loss than BeXRBs at supernova. We argue that the magnitude of $V_{\rm pec}$ could be used as a complementary feature to distinguish between Be and supergiant systems. These findings extend previous inferences based on two-dimensional kinematics from Hipparcos, and may be explained by the differing nature of the respective progenitors systems between the source classes at the instant of supernova.

astro-ph.HE↗

arXiv2025

Comprehensive Radio Monitoring of the Black Hole X-ray Binary Swift J1727.8$-$1613 during its 2023$-$2024 Outburst

This work presents comprehensive multi-frequency radio monitoring of the black hole low-mass X-ray binary Swift J1727.8$-$1613, which underwent its first recorded outburst after its discovery in August 2023. Through a considerable community effort, we have coalesced the data from multiple, distinct observing programs; the light curves include ${\sim} 10$ months and 197 epochs of monitoring from 7 radio facilities with observing frequencies ranging from (approximately) 0.3$-$230GHz. The primary purpose of this work is to provide the broader astronomical community with these light curves to assist with the interpretation of other observing campaigns, particularly non-radio observing frequencies. We discuss the phenomenological evolution of the source, which included: (i) multiple radio flares consistent with the launching of discrete jet ejections, the brightest of which reached $\sim$ 1 Jy; (ii) temporally evolving radio spectral indices ($α$), reaching values steeper than expected for optically-thin synchrotron emission ($α{<} -1$) and emission with significant radiative cooling ($α< -1.5$). We have published a digital copy of the data and intend for this work to set a precedent for the community to continue releasing comprehensive radio light curves of future low-mass X-ray binary outbursts.

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arXiv2025

Gone with the Wind: JWST-MIRI Unveils a Strong Outflow from the Quiescent Stellar-Mass Black Hole A0620-00

We present new observations of the black hole X-ray binary A0620-00 using the Mid-Infrared Instrument on the James Webb Space Telescope, during a state where the X-ray luminosity is 9 orders of magnitude below Eddington, and coordinated with radio, near-infrared and optical observations. The goal is to understand the nature of the excess mid-infrared (MIR) emission originally detected by Spitzer red-ward of 8 $μ$m. The stellar-subtracted MIR spectrum is well-modeled by a power law with a spectral index of $α=0.72\pm0.01$, where the flux density scales with frequency as $F_ν\propto ν^α$. The spectral characteristics, along with rapid variability--a 40% flux flare at 15$μ$m and 25% achromatic variability in the 5-12 $μ$m range--rule out a circumbinary disk as the source of the MIR excess. The Low Resolution Spectrometer reveals a prominent emission feature at 7.5 $μ$m, resulting from the blend of three hydrogen recombination lines. While the contribution from partially self-absorbed synchrotron radiation cannot be ruled out, we argue that thermal bremsstrahlung from a warm (a few $10^4$ K) wind accounts for the MIR excess; the same outflow is responsible for the emission lines. The inferred mass outflow rate indicates that the system's low luminosity is due to a substantial fraction of the mass supplied by the donor star being expelled through a wind rather than accreted onto the black hole.

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arXiv2025

The very high X-ray polarisation of accreting black hole IGRJ17091-3624 in the hard state

We report the first detection of the X-ray polarisation of the transient black hole X-ray binary IGRJ17091-3624 taken with the Imaging X-ray polarimetry Explorer (IXPE) in March 2025, and present the results of an X-ray spectro-polarimetric analysis. The polarisation was measured in the 2--8 keV band with 5.2$σ$ statistical confidence. We report a polarisation degree (PD) of $9.1\pm1.6$ per cent and a polarisation angle of $83^{\circ} \pm 5^{\circ}$ (errors are $1σ$ confidence). There is a hint of a positive correlation of PD with energy that is not statistically significant. We report that the source is in the corona-dominated hard state, which is confirmed by a hard power-law dominated spectrum with weak reflection features and the presence of a Type-C quasi-periodic oscillation at $\sim0.2$~Hz. The orientation of the emitted radio jet is not known, and so we are unable to compare it with the direction of X-ray polarization, but we predict the two to be parallel if the geometry is similar to that in Cygnus X-1 and Swift J1727.8-1613, the two hard state black hole binaries previously observed by IXPE. In the Comptonisation scenario, the high observed PD requires a very favourable geometry of the corona, a high inclination angle (supported by the presence of a dip in the light curve) and possibly a mildly relativistic outflow and/or scattering in an optically thick wind.

astro-ph.HE↗

arXiv2025

Rapid far-infrared spectral timing of X-ray binaries with PRIMA

The most powerful cosmic engines in our universe are fueled by compact objects. These objects accrete large amounts of material and eject matter in the form of jets. Recent groundbreaking discoveries of gravitational waves from merging compact objects and the direct imaging of the black hole shadows with the Event Horizon Telescope represent major steps forward in our understanding of such systems. However, there exists a large population of stellar-mass compact objects in our own Galaxy, present in X-ray binaries (XRBs), which provide better laboratories with which to study the processes of accretion and ejection. XRBs produce highly variable emissions on timescales ranging from milliseconds (for light-travel time in the region close to the compact object) to weeks (governing the mass-inflow process). Therefore, high-time resolution observations can be a powerful tool to study these systems. However, as XRBs emit across the electromagnetic spectrum, a suite of facilities is needed to take full advantage of these techniques. The PRIMA Observatory (PRobe far-Infrared Mission for Astrophysics) will provide unique access to a wavelength range that has not been sampled in XRBs, representing an exciting new possibility for characterizing rapid time-domain phenomena of XRBs (and potentially other transient sources) in the far-infrared regime.

astro-ph.HE↗

arXiv2025

Ultraviolet spectroscopy of the black hole X-ray binary MAXI J1820+070 across a state transition

We present ultraviolet (UV) spectroscopic observations covering three distinct accretion states of the low-mass X-ray binary (LMXB) MAXI J1820+070: the luminous hard state, a hard-intermediate state and the soft state. Our observations were obtained during the 2018 eruption of MAXI J1820+070 with the Hubble Space Telescope (HST) and AstroSat observatory. The extinction towards the source turns out to be low - $\rm E_{B-V} = 0.2 \pm 0.05$ - making it one of the best UV accretion laboratories among LMXBs. Remarkably, we observe only moderate differences between all three states, with all spectra displaying similar continuum shapes and emission lines. Moreover, the continua are not well-described by physically plausible irradiated disc models. All of this challenges the standard reprocessing picture for UV emission from erupting LMXBs. The UV emission lines are double-peaked, with high-ionization lines displaying higher peak-to-peak velocities. None of the lines display obvious outflow signatures, even though blue-shifted absorption features have been seen in optical and near-infrared lines during the hard state. The emission line ratios are consistent with normal abundances, suggesting that the donor mass at birth was low enough to avoid CNO processing ($\rm M_{2,i} \lesssim 1.0 - 1.5 {\mathrm M_{\odot}}$). Finally, we study the evolution of UV variability in our time-resolved HST observations (hard and hard-intermediate states). All UV power spectra can be modelled with a broken power-law, superposed on which we tentatively detect the $\simeq 18$s quasi-periodic oscillation (QPO) that has been seen in other spectral bands.

astro-ph.HE↗

arXiv2025

Characterisation of H$β$ spectra from EXO 051910+3737.7 X-rays binaries

We investigate the spectral characteristics of the Be/X-ray binary system, EXO 051910+3737.7, in which Be/X-ray systems are the largest sub-class of high-mass X-ray binaries. Spectroscopic observations are taken by the Thai National Telescope (TNT) with a Medium-RESolution spectrograph (MRES) instrument for seven nights spanning from 2020 to 2021. Our primary focus is directed towards the analysis of two Balmer lines, namely H$α$ and H$β$, given that Be stars typically exhibit emission features in at least one of these hydrogen Balmer lines during certain phases. Our observations reveal split Balmer emission lines throughout the entire duration of our monitoring. Double Gaussian profiles were employed for line fitting to characterize these lines. The presence of double peaks in the Balmer lines indicates the presence of asymmetries within the circumstellar disc. We then analyze V/R variations and the changes in H$β$ spectra. Our analysis of V/R variation which Violet (V) and Red (R) peak intensity components, revealed rapid fluctuations occurring within a single day, although determining the precise periodicity was constrained by instrumental limitations and the duration of observability. Furthermore, employing observed the wavelength differences ($Δλ$) in conjunction with typical Be star parameters allowed us to estimate the radius ($r_β$) of the H$β$ emitting envelope. The average value was calculated to be 2.585$r_*$, with a standard deviation of 0.050$r_*$.

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