Publications (101)
Investigating the observational properties of Type Ib supernova SN 2017iro
Brajesh Kumar, Avinash Singh, D. K. Sahu +1
We report results of optical imaging and low-resolution spectroscopic monitoring of supernova (SN) 2017iro that occurred in the nearby (\,31 Mpc) galaxy NGC 5480. The \ion{He…
GROWTH on S190426c II: GROWTH-India Telescope search for an optical counterpart with a custom image reduction and candidate vetting pipeline
Harsh Kumar, Varun Bhalerao, G. C. Anupama +17
S190426c / GW190426_152155 was the first probable neutron star - black hole merger candidate detected by the LIGO-Virgo Collaboration. We undertook a tiled search for optical count…
Observation of mulitply imaged quasars with the 4-m ILMT
Talat Akhunov, Bhavya Ailawadhi, Ermanno Borra +12
Gravitationally lensed quasars (GLQs) are known to potentially provide an independent way of determining the value of the Hubble-Lemaître parameter , to probe the dark matt…
Intermediate Luminosity Type Iax SN 2019muj With Narrow Absorption Lines: Long-Lasting Radiation Associated With a Possible Bound Remnant Predicted by the Weak Deflagration Model
Miho Kawabata, Keiichi Maeda, Masayuki Yamanaka +23
We present comprehensive spectroscopic and photometric analyses of the intermediate luminosity Type Iax supernova (SN Iax) 2019muj based on multi-band datasets observed through the…
Light curve and spectral evolution of the Type IIb SN 2011fu
Brajesh Kumar, S. B. Pandey, D. K. Sahu +13
We present the low-resolution spectroscopic and UBVRI broad-band photometric investigations of the Type IIb supernova 2011fu, discovered in UGC 01626. The photometric follow-up of…
On the line profile changes observed during the X2.2 class flare in the active region NOAA 11158
A. Raja Bayanna, Brajesh Kumar, P. Venkatakrishnan +4
The solar active region NOAA 11158 produced a series of flares during its passage through the solar disk. The first major flare (of class X2.2) of the current solar cycle occurred…
On the flare induced seismicity in the active region NOAA 10930 and related enhancement of global waves in the sun
Brajesh Kumar, P. Venkatakrishnan, Savita Mathur +2
A major flare (of class X3.4) occurred on 13 December 2006 in the active region NOAA 10930. The energy released during flares is also known to induce acoustic oscillations in the S…
Surface Brightness Properties of LSB Galaxies with the International Liquid Mirror Telescope
Jiuyang Fu, Bhavya Ailawadhi, Talat Akhunov +11
Low surface brightness (LSB) galaxies make up a significant fraction of the luminosity density of the local universe. Their low surface brightness suggests a different formation an…
Multiband Simultaneous Photometry of Type II SN 2023ixf with Mephisto and the Twin 50-cm Telescopes
Yuan-Pei Yang, Xiangkun Liu, Yu Pan +13
SN 2023ixf, recently reported in the nearby galaxy M101 at a distance of , was one of the closest and brightest core-collapse supernovae (CCSNe) in the last decade.…
A study of the propagation of magnetoacoustic waves in small-scale magnetic fields using solar photospheric and chromospheric Dopplergrams: HMI/SDO and MAST observations
Hirdesh Kumar, Brajesh Kumar, S. P. Rajaguru +2
In this work, we present a study of the propagation of low-frequency magneto-acoustic waves into the solar chromosphere within small-scale inclined magnetic fields over a quiet-mag…
SN 2017hpa: A carbon-rich type Ia supernova
Anirban Dutta, Avinash Singh, G. C. Anupama +2
We present the optical (UBVRI) and ultraviolet (Swift-UVOT) photometry, and optical spectroscopy of Type Ia supernova SN 2017hpa. We study broadband UV+optical light curves and low…
ASASSN-16fp (SN 2016coi): A transitional supernova between Type Ic and broad-lined Ic
Brajesh Kumar, A. Singh, S. Srivastav +2
We present results based on a well sampled optical () and ultraviolet ({\it Swift}/UVOT) imaging, and low-resolution optical spectroscopic follow-up observations of the near…
Astrometric and photometric calibrators for the 4-m International Liquid Mirror Telescope
Naveen Dukiya, Bhavya Ailawadhi, Talat Akhunov +11
The International Liquid Mirror Telescope (ILMT) is a 4-meter class survey telescope. It achieved its first light on 29 April 2022 and is now undergoing the commissionin…
Revealing nature of GRB 210205A, ZTF21aaeyldq (AT2021any), and follow-up observations with the 4K4K CCD Imager+3.6m DOT
Rahul Gupta, Amit Kumar, Shashi Bhushan Pandey +14
Optical follow-up observations of optical afterglows of gamma-ray bursts are crucial to probe the geometry of outflows, emission mechanisms, energetics, and burst environments. We…
On the seismic emission in sunspots associated with Lorentz force changes accompanying major solar flares
Hirdesh Kumar, Brajesh Kumar
Solar flares are known to generate seismic waves in the Sun. We present a detailed analysis of seismic emission in sunspots accompanying M- and X-class solar flares. For this purpo…
SN 2007uy - metamorphosis of an aspheric Type Ib explosion
Rupak Roy, Brijesh Kumar, Justyn R. Maund +13
The supernovae of Type Ibc are rare and the detailed characteristics of these explosions have been studied only for a few events. Unlike Type II SNe, the progenitors of Type Ibc ha…
SN 2017gmr: An energetic Type II-P supernova with asymmetries
Jennifer E. Andrews, D. J. Sand, S. Valenti +77
We present high-cadence ultraviolet (UV), optical, and near-infrared (NIR) data on the luminous Type II-P supernova SN 2017gmr from hours after discovery through the first 180 days…
SN 2015as: A low luminosity Type IIb supernova without an early light curve peak
Anjasha Gangopadhyay, Kuntal Misra, A. Pastorello +14
We present results of the photometric (from 3 to 509 days past explosion) and spectroscopic (up to 230 days past explosion) monitoring campaign of the He-rich Type IIb supernova (S…
Study of Faint Galaxies in the Field of GRB 021004
Yu. V. Baryshev, I. V. Sokolov, A. S. Moskvitin +3
We present an analysis of BVRcIc observations of the field sized around 4' x 4' centered at the host galaxy of the gamma-ray burst GRB 021004 with the 6-m BTA telescope of the Spec…
Sn 2008in - bridging the gap between normal and faint supernovae of type IIP
Rupak Roy, Brijesh Kumar, Stefano Benetti +18
We present optical photometric and low-resolution spectroscopic observations of the Type II plateau supernova (SN) 2008in, which occurred in the outskirts of the nearly face-on spi…
Detection and Identification of Asteroids with the 4-m ILMT
Anna Pospieszalska-Surdej, Bhavya Ailawadhi, Talat Akhunov +12
A very unique strength of the Devasthal Observatory is its capability of detecting optical transients with the 4-m International Liquid Mirror Telescope (ILMT) and to rapidly follo…
On the propagation of gravity waves in the lower solar atmosphere in different magnetic configurations
Hirdesh Kumar, Brajesh Kumar, S. P. Rajaguru
Gravity waves are generated by turbulent subsurface convection overshooting or penetrating locally into a stably stratified medium. While propagating energy upwards, their characte…
Can major solar flares excite high-frequency global waves in the Sun ?
Brajesh Kumar, Savita Mathur, R. A. Garcia +1
The study of low-degree high-frequency waves in the Sun can provide new insight into the dynamics of the deeper layers of the Sun. Here, we present the analysis of the velocity obs…
The 4m International Liquid Mirror Telescope project
Jean Surdej, Bhavya Ailawadhi, Talat Akhunov +12
The International Liquid Mirror Telescope (ILMT) project is a scientific collaboration in observational astrophysics between the Li{è}ge Institute of Astrophysics and Geophysics (…
Accessibility of the ILMT survey data
Kuntal Misra, Bhavya Ailawadhi, Talat Akhunov +11
The 4m International Liquid Mirror Telescope (ILMT) continuously scans a 22 wide strip of the zenithal sky and records the images in three broadband filters (g', r' and i') usin…
The optical photometric and spectroscopic investigation of Type IIP supernova 2012A
Rupak Roy, Firoza Sutaria, Subhash Bose +11
Supernova 2012A was discovered on 7.39UT, January, 2012 in the nearby galaxy NGC 3239 at an unfiltered magnitude of 14.6 and classified spectroscopically as a Type IIP event. Here,…
Supernova 2012aw - a high-energy clone of archetypal type IIP SN 1999em
Subhash Bose, Brijesh Kumar, Firoza Sutaria +8
We present densely-sampled UBVRI/griz photometric and low-resolution (6-10A) optical spectroscopic observations from 4 to 270 days after explosion of a newly discovered type II SN…
Survey of Variables with the ILMT
Baldeep Grewal, Bhavya Ailawadhi, Talat Akhunov +11
Nestled in the mountains of Northern India, is a 4-metre rotating dish of liquid mercury. Over a 10-year period, the International Liquid Mirror Telescope (ILMT) will survey 117 sq…
Automated transient detection in the context of the 4m ILMT
Kumar Pranshu, Bhavya Ailawadhi, Talat Akhunov +11
In the era of sky surveys like Palomar Transient Factory (PTF), Zwicky Transient Facility (ZTF) and the upcoming Vera Rubin Observatory (VRO) and ILMT, a plethora of image data wil…
Early-phase simultaneous multiband observations of the Type II supernova SN 2024ggi with Mephisto
Xinlei Chen, Brajesh Kumar, Xinzhong Er +24
We present early-phase good-cadence (hour-to-day) simultaneous multiband ( and bands) imaging of the nearby supernova SN~2024ggi, which exploded in the nearby galaxy, NG…
Astrometric and photometric standard candidates for the upcoming 4-m ILMT survey
Naveen Dukiya, Kuntal Misra, Bikram Pradhan +5
The International Liquid Mirror Telescope (ILMT) is a 4-meter class survey telescope that has recently achieved first light and is expected to swing into full operations by 1st Jan…
First Lunar Occultation Results with the TIRCAM2 Near-Infrared Imager at the Devasthal 3.6-m Telescope
Saurabh Sharma, Andrea Richichi, Devendra K. Ojha +7
TIRCAM2 is the facility near-infrared Imager at the Devasthal 3.6-m telescope in northern India, equipped with an Aladdin III InSb array detector. We have pioneered the use of TIRC…
First light preparations of the 4m ILMT
Brajesh Kumar, Hitesh Kumar, Khushal Singh Dangwal +8
The 4m International Liquid Mirror Telescope (ILMT) is a zenith-pointing optical observing facility at ARIES Devasthal observatory (Uttarakhand, India). The first light preparatory…
Follow-up strategy of ILMT discovered supernovae
Brajesh Kumar, Bhavya Ailawadhi, Talat Akhunov +11
The 4m International Liquid Mirror Telescope (ILMT) facility continuously scans the same sky strip (22 wide) on each night with a fixed pointing towards the zenith d…
MUSSES2020J: The Earliest Discovery of a Fast Blue Ultraluminous Transient at Redshift 1.063
Ji-an Jiang, Naoki Yasuda, Keiichi Maeda +22
In this Letter, we report the discovery of an ultraluminous fast-evolving transient in rest-frame UV wavelengths, MUSSES2020J, soon after its occurrence by using the Hyper Suprime-…
Photometric, polarimetric, and spectroscopic studies of the luminous, slow-decaying Type Ib SN 2012au
S. B. Pandey, Amit Kumar, Brajesh Kumar +15
Optical, near-infrared (NIR) photometric and spectroscopic studies, along with the optical imaging polarimetric results for SN 2012au, are presented in this article to constrain th…
A Study of the relation between intensity oscillations and magnetic field parameters in a Sunspot: Hinode Observations
Ankala Raja Bayanna, Shibu K Mathew, Brajesh Kumar +2
We present properties of intensity oscillations of a sunspot in the photosphere and chromosphere using G~band and CaIIH filtergrams from Hinode. Intensity power maps as function of…
On the observational behaviour of the highly polarized Type IIn supernova SN 2017hcc
Brajesh Kumar, Chakali Eswaraiah, Avinash Singh +10
We present the results based on photometric ( UVOT), broad-band polarimetric ( and -band) and optical spectroscopic observations of the Type IIn supernova (SN) 2017hcc…
Intranight optical variability of γ-ray loud Narrow Line Seyfert 1 galaxies
Vaidehi S. Paliya, C. S. Stalin, Brijesh Kumar +4
The Large Area Telescope (LAT) onboard the {\it Fermi} Gamma Ray Space Telescope has detected γ-ray emission from some Narrow Line Seyfert 1(NLSy1) galaxies. This indicates the pr…
The 4m International Liquid Mirror Telescope: Construction, operation, and science
Jean Surdej, Paul Hickson, Kuntal Misra +26
The International Liquid Mirror Telescope (ILMT) project was motivated by the need for an inexpensive 4 metre diameter optical telescope that could be devoted entirely to astronomi…
SunPhot: Preparations for an upcoming quasar variability survey with the International Liquid Mirror Telescope
Ethen Sun, Bhavya Ailawadhi, Talat Akhunov +11
Recent research suggests a correlation between the variability and intrinsic brightness of quasars. If calibrated, this could lead to the use of quasars on the cosmic distance ladd…
Investigation of the stellar content in the western part of the Carina nebula
Brajesh Kumar, Saurabh Sharma, Jean Manfroid +4
We obtained deep H photometric data of the field situated to the west of the main Carina nebula and centered on WR~22. Medium-resolution optical spectroscopy of a subsa…
The Pre-explosion Environments and The Progenitor of SN 2023ixf from the Hobby Eberly Telescope Dark Energy Experiment (HETDEX)
Chenxu Liu, Xinlei Chen, Xinzhong Er +20
Supernova (SN) 2023ixf was discovered on May 19th, 2023. The host galaxy, M101, was observed by the Hobby Eberly Telescope Dark Energy Experiment (HETDEX) collaboration over the pe…
Serendipitous Detection of Orbital Debris by the International Liquid Mirror Telescope: First Results
Paul Hickson, Bhavya Ailawadhi, Talat Akhunov +11
Orbital debris presents a growing risk to space operations, and is becoming a significant source of contamination of astronomical images. Much of the debris population is uncatalog…
PyLMT: A transient detection pipeline for the 4-m International Liquid Mirror Telescope
Kumar Pranshu, Kuntal Misra, Bhavya Ailawadhi +7
The International Liquid Mirror Telescope (ILMT) is a 4-m aperture, zenith-pointing telescope with a field-of-view of 22', situated in the foothills of the Himalayas. The telescope…
ASASSN-14dq: A fast-declining type II-P Supernova in a low-luminosity host galaxy
Avinash Singh, S. Srivastav, Brajesh Kumar +2
Optical broadband (UBVRI) photometric and low-resolution spectroscopic observations of the type II-P supernova (SN) ASASSN-14dq are presented. ASASSN-14dq exploded in a low-luminos…
SN 2008gz - most likely a normal type IIP event
Rupak Roy, Brijesh Kumar, Alexander S. Moskvitin +10
We present BV RI photometric and low-resolution spectroscopic investigation of a type II core-collapse supernova (SN) 2008gz, which occurred in a star forming arm and within a half…
Performance of the 4-m International Liquid Mirror Telescope tested in two fields at high and low ecliptic and galactic latitudes
Sara Filali, Kumar Pranshu, Jean Surdej +10
The 4-m International Liquid Mirror Telescope (ILMT) offers a unique opportunity to detect transients in a narrow strip of sky. We explore ILMT's potential to detect astrometric an…
Variation of Acoustic Power with Magnetic Field as seen in Gong+ Data
P. Venkatakrishnan, Brajesh Kumar, S. C. Tripathy
The acoustic spectra in sunspots are known to be richer in higher frequency power. We have attempted a generalized study of the effect of magnetic fields on the shape of the acoust…
Early Near-Infrared Excess and Rapid Disk-Corona Evolution in the Tidal Disruption Event 2024aepd
Yongxin Wu, Yanan Wang, Thomas M. Reynolds +38
The paper reports multi-wavelength observations of tidal disruption event 2024aepd, revealing an early near‑infrared excess and a rapid transition from a thermal X‑ray disk to a ha…
Necessity of a TDI optical corrector for ILMT observations
Vibhore Negi, Bhavya Ailawadhi, Talat Akhunov +11
The International Liquid Mirror Telescope (ILMT) has recently become operational at the Devasthal Observatory of ARIES, Nainital, India. The ILMT observes in the Time delay integra…
SN 2016B a.k.a ASASSN-16ab: a transitional type II supernova
Raya Dastidar, Kuntal Misra, Mridweeka Singh +12
We present photometry, polarimetry and spectroscopy of the Type II supernova ASASSN-16ab/SN 2016B in PGC 037392. The photometric and spectroscopic follow-up commenced about two wee…
Optical and NIR observations of the nearby type Ia supernova SN 2014J
Shubham Srivastav, J. P. Ninan, Brajesh Kumar +4
Optical and NIR observations of the type Ia supernova SN 2014J in M82 are presented. The observed light curves are found to be similar to normal SNe Ia, with a decline rate paramet…
Analysis of hysteresis effect in p mode frequency shifts and solar activity indices
S. C. Tripathy, Brajesh Kumar, Kiran Jain +1
Using intermediate degree p mode frequency data sets for solar cycle 22, we find that the frequency shifts and magnetic indices show a `hysteresis' phenomenon. It is observed that…
Astrometric Calibration of the 4-m International Liquid Mirror Telescope Observations
Vibhore Negi, Naveen Dukiya, Gokul Singh Mehra +12
The 4-m International Liquid Mirror Telescope (ILMT) is a dedicated time domain survey telescope that continuously scans the zenithal sky over the Indian Himalayas in the g', r' an…
SN 2024gy: Multi-epoch Spectroscopic Features Suggestive of Delayed Detonation in a Type Ia Supernova
Liping Li, Zhenyu Wang, Jialian Liu +28
We present photometric and spectroscopic observations of SN 2024gy, a Type Ia supernova (SN Ia) exhibiting high-velocity features (HVFs) in its early-time spectra. This SN reaches…
Observational properties of a Type Ib Supernova MASTER OT J120451.50+265946.6 in NGC 4080
Mridweeka Singh, Kuntal Misra, D. K. Sahu +12
MASTER OT J120451.50+265946.6 (M12045), discovered by the MASTER Global Robotic Net, is a Type Ib supernova (SN) that exploded in NGC 4080. We present the {\it BVRI} photometric an…
SN 2020sck: deflagration in a carbon-oxygen white dwarf
Anirban Dutta, D. K. Sahu, G. C. Anupama +7
We present optical UBVRI photometry and low-to-medium resolution spectroscopic observations of type Iax SN 2020sck spanning -5.5 d to +67 d from maximum light in the B-band. From t…
An automated photometric pipeline for the ILMT data
Bhavya Ailawadhi, Talat Akhunov, Ermanno Borra +11
The International Liquid Mirror Telescope (ILMT) is a 4-meter survey telescope continuously observing towards the zenith in the SDSS g', r', and i' bands. This survey telescope is…
SN 2010kd: Photometric and Spectroscopic Analysis of a Slow-Decaying Superluminous Supernova
Amit Kumar, Shashi Bhushan Pandey, Reka Konyves-Toth +21
This paper presents data and analysis of SN 2010kd, a low-redshift () H-deficient superluminous supernova (SLSN), based on ultraviolet/optical photometry and optical spe…
Analysis of sudden variations in photospheric magnetic fields during a large flare and their influences in the solar atmosphere
Brajesh Kumar, A. Raja Bayanna, P. Venkatakrishnan +1
The solar active region NOAA 11719 produced a large two-ribbon flare on 11 April 2013. We have investigated the sudden variations in the photospheric magnetic fields in this active…
Simultaneous Multiband Photometry of the Early Optical Afterglow of GRB 240825A with Mephisto
Yehao Cheng, Yu Pan, Yuan-Pei Yang +19
Gamma-ray bursts (GRBs) are the most luminous transients in the universe. The interaction of the relativistic jet with the circumburst medium produces an afterglow and generates mu…
Far-Ultraviolet to Near-Infrared Observations of SN 2023ixf: A high energy explosion engulfed in complex circumstellar material
Rishabh Singh Teja, Avinash Singh, Judhajeet Basu +13
We present early-phase panchromatic photometric and spectroscopic coverage spanning far-ultraviolet (FUV) to the near-infrared (NIR) regime of the nearest hydrogen-rich core-collap…
The upcoming 4m ILMT facility and data reduction pipeline testing
Brajesh Kumar, Vibhore Negi, Bhavya Ailawadhi +5
The 4m International Liquid Mirror Telescope (ILMT) installation activities have recently been completed at the Devasthal observatory (Uttarakhand, India). The ILMT will perform co…
On the flare induced high-frequency global waves in the Sun
Brajesh Kumar, Savita Mathur, R. A. Garcia +1
Recently, Karoff and Kjeldsen (2008) presented evidence of strong correlation between the energy in the high-frequency part (5.3<ν<8.3 mHz) of the acoustic spectrum of the Sun and…
Differential rotation of the solar transition region from STEREO/EUVI 30.4 nm images
Jaidev Sharma, Brajesh Kumar, Anil K Malik +1
The solar photosphere, chromosphere and corona are known to rotate differentially as a function of latitude. To date, it is unclear if the solar transition region also rotates diff…
Optical studies of two stripped envelope supernovae SN 2015ap (Type Ib) and SN 2016P (Type Ic)
Anjasha Gangopadhyay, Kuntal Misra, D. K. Sahu +14
We present the photometric and spectroscopic studies of a Type Ib SN 2015ap and a Type Ic SN 2016P. SN 2015ap is one of the bright (M = 18.04 mag) Type Ib while SN 2016P l…
Search for Spatial Variability in the Solar Acoustic Spectrum
P. Venkatakrishnan, Brajesh Kumar, S. C. Tripathy
Motivated by the various examples of spatial variability in the power of the acoustic spectrum, we attempted to look for spatial variability in the peak frequency of the spectrum.…
SN 2018hna: 1987A-like supernova with a signature of shock breakout
Avinash Singh, D. K. Sahu, G. C. Anupama +22
High cadence ultraviolet, optical and near-infrared photometric and low-resolution spectroscopic observations of the peculiar Type II supernova (SN) 2018hna are presented. The earl…
SN 2020jfo: A short plateau Type II supernova from a low mass progenitor
Rishabh Singh Teja, Avinash Singh, D. K. Sahu +3
We present spectroscopic and photometric observations of the Type IIP supernova, SN 2020jfo, in ultraviolet and optical wavelengths. SN 2020jfo occurred in the spiral galaxy M61 (N…
Supernovae study: Context of the 4-m ILMT facility
Brajesh Kumar, S. B. Pandey, Kanhaiya L. Pandey +2
The upcoming 4-m International Liquid Mirror Telescope (ILMT) facility will perform deep imaging (in single scan 22 mag.) of a narrow strip of sky each clear night in th…
The zenithal 4-m International Liquid Mirror Telescope: a unique facility for supernova studies
Brajesh Kumar, Kanhaiya L. Pandey, S. B. Pandey +4
The 4-m International Liquid Mirror Telescope (ILMT) will soon become operational at the newly developed Devasthal observatory near Nainital (Uttarakhand, India). Coupled with a 4k…
Broad band polarimetric investigation of Type IIP supernova 2013ej
Brajesh Kumar, S. B. Pandey, C. Eswaraiah +1
We present results based on follow-up observations of the Type II-plateau supernova (SN) 2013ej at 6 epochs spanning a total duration of 37 d. The -band linear polarim…
Observational signature of circumstellar interaction and Ni-mixing in the Type II Supernova 2016gfy
Avinash Singh, Brajesh Kumar, Takashi J. Moriya +5
The optical and ultra-violet broadband photometric and spectroscopic observations of the Type II supernova (SN) 2016gfy are presented. The -band light curve (LC) shows a distinc…
Main-sequence variable stars in young open cluster NGC 1893
Sneh Lata, Ram Kesh Yadav, A. K. Pandey +5
In this paper we present time series photometry of 104 variable stars in the cluster region NGC 1893. The association of the present variable candidates to the cluster NGC 1893 has…
SN 2013ab : A normal type IIP supernova in NGC 5669
Subhash Bose, Stefano Valenti, Kuntal Misra +13
We present densely-sampled ultraviolet/optical photometric and low-resolution optical spectroscopic observations of the type IIP supernova 2013ab in the nearby (24 Mpc) galax…
The Fast, Luminous Ultraviolet Transient AT2018cow: Extreme Supernova, or Disruption of a Star by an Intermediate-Mass Black Hole?
Daniel A. Perley, Paolo A. Mazzali, Lin Yan +60
Wide-field optical surveys have begun to uncover large samples of fast (t_rise < 5d), luminous (M_peak < -18), blue transients. While commonly attributed to the breakout of a super…
Exploring the optical behaviour of a type Iax supernova SN 2014dt
Mridweeka Singh, Kuntal Misra, D. K. Sahu +9
We present optical photometric (upto 410 days since ) and spectroscopic (upto 157 days since ) observations of a Type Iax supernova (SN) 2014dt lo…
Investigation of Phase Shift and Travel Time of Acoustic Waves in the Lower Solar Atmosphere Using Multi-Height Velocities
Hirdesh Kumar, Brajesh Kumar, Shibu K. Mathew +2
We report and discuss phase-shift and phase travel time of low-frequency (ν < 5.0 mHz) acoustic waves estimated within the photosphere and photosphere-chromosphere interface regio…
Distinct Fe-K Line Complexes in MAXI J1744-294 Revealed by XRISM High-Resolution Spectroscopy
Kaushik Chatterjee, Santanu Mondal, Biswaraj Palit +7
The newly discovered Galactic transient MAXI J1744-294 went into its first X-ray outburst in 2025. We study the spectral properties of this source in the 2-10 keV energy band durin…
SN 2020ank: a bright and fast-evolving H-deficient superluminous supernova
Amit Kumar, Brajesh Kumar, S. B. Pandey +7
We investigate the observational properties of a hydrogen-deficient superluminous supernova (SLSN) SN 2020ank (at z = 0.2485), with the help of early phase observations carried out…
A multi-wavelength analysis of a collection of short-duration GRBs observed between 2012-2015
S. B. Pandey, Y. Hu, A. J. Castro-Tirado +71
We investigate the prompt emission and the afterglow properties of short duration gamma-ray burst (sGRB) 130603B and another eight sGRB events during 2012-2015, observed by several…
Peering into the Heart of the Giant Molecular Cloud G148.24+00.41: A Deep Near-infrared View of the Newly Hatched Cluster FSR 655
Vineet Rawat, M. R. Samal, D. K. Ojha +5
We present a detailed near-infrared study of an embedded cluster located in the hub of the giant molecular cloud G148.24+00.41 of mass 10 , with the TANSPEC inst…
On the signatures of flare-induced global waves in the Sun: GOLF and VIRGO observations
Brajesh Kumar, Savita Mathur, Rafael A. Garcia +1
Recently, several efforts have been made to identify the seismic signatures of flares and magnetic activity in the Sun and Sun-like stars. In this work, we have analyzed the disk-i…
Flash ionization signatures in the type Ibn supernova SN 2019uo
Anjasha Gangopadhyay, Kuntal Misra, Daichi Hiramatsu +26
We present photometric and spectroscopic observations of the type Ibn supernova (SN) 2019uo, the second ever SN Ibn with flash ionization (He II, C III, N III) features in its earl…
SN 2018gj: A Short-plateau Type II Supernova with Persistent Blue-shifted H-alpha Emission
Rishabh Singh Teja, Avinash Singh, D. K. Sahu +7
We present an extensive, panchromatic photometric (UV, Optical, and NIR) and low-resolution optical spectroscopic coverage of a Type IIP supernova SN 2018gj that occurred on the ou…
Evidence of strong relationship between hemispheric asymmetry in solar coronal rotation and solar activity during solar cycle 24
Jaidev Sharma, Anil K Malik, Brajesh Kumar +1
In this article, we report an evidence of very high and statistically significant relationship between hemispheric asymmetry in solar coronal rotation rate and solar activity. Our…
Kilonova Luminosity Function Constraints based on Zwicky Transient Facility Searches for 13 Neutron Star Mergers
Mansi M. Kasliwal, Shreya Anand, Tomas Ahumada +100
We present a systematic search for optical counterparts to 13 gravitational wave (GW) triggers involving at least one neutron star during LIGO/Virgo's third observing run. We searc…
Photometric and spectroscopic evolution of the peculiar Type IIn SN 2012ab
Anjasha Gangopadhyay, Massimo Turatto, Stefano Benetti +15
We present an extensive ( 1200 d) photometric and spectroscopic monitoring of the Type IIn supernova (SN) 2012ab. After a rapid initial rise leading to a bright maximum (M$_{…
Optical spectroscopic characterization of Fermi blazar candidates of uncertain type with TNG and DOT: First Results
Amanda Olmo-GarcÃa, Vaidehi S. Paliya, Nuria Ãlvarez Crespo +4
The classification of gamma-ray-detected blazar candidates of uncertain type (BCU) is a relevant problem in extragalactic gamma-ray astronomy. Here we report the optical spectrosco…
A year-long representation of the ILMT observations in different coordinate systems
Monalisa Dubey, Bhavya Ailawadhi, Talat Akhunov +11
The 4m International Liquid Mirror Telescope (ILMT) is the first optical survey telescope in India that performs zenithal observations of a 22 wide strip of the sky. To determin…
Formation and Eruption of Filament Channel in Solar Active Region 12975: Insights from Observations and Simulations of Magnetic Field Evolution
Dinesh Mishra, P. Vemareddy, Brajesh Kumar
We studied the magnetic field evolution of active region (AR) 12975 using a time-dependent magnetofrictional (TMF) model. This AR produced two consecutive CMEs associated with M-cl…
p-modes in and away from a sunspot
Brajesh Kumar, R. Jain, S. C. Tripathy +2
A time series of GONG Dopplergrams for the period 10-14 May 1997 from Udaipur and Big Bear sites has been used to measure the velocity fluctuations in the sunspot (NOAA active regi…
Two years of shock interaction tracing three phases of evolution: the explosion of a Type IIn supernova, SN 2019vxm
Gitika Rameshan, Rishabh Singh Teja, D. K. Sahu +10
We present multi-wavelength photometric and optical spectroscopic observations of the long-lived interacting supernova SN 2019vxm, spanning more than two years after the explosion.…
The 4m International Liquid Mirror Telescope: a brief history and some preliminary scientific results
Jean Surdej, Bhavya Ailawadhi, Talat Akhunov +12
The present article is based upon an invited talk delivered at the occasion of the inauguration of the 4m International Liquid Mirror Telescope (ILMT) which took place in Devasthal…
Broad band polarimetric follow-up of Type IIP SN 2012aw
Brajesh Kumar, S. B. Pandey, C. Eswaraiah +1
We present the results based on R-band polarimetric follow-up observations of the nearby (~10 Mpc) Type II-plateau SN 2012aw. Starting from ~10 days after the SN explosion, these p…
Photometric and polarimetric observations of fast declining Type II supernovae 2013hj and 2014G
Subhash Bose, Brijesh Kumar, Kuntal Misra +5
We present broadband photometric and polarimetric observations of two type II supernovae (SNe) 2013hj and 2014G. SN 2014G is a spectroscopically classified type IIL event, which we…
High-redshift GRB 140304A at z = 5.282 with flaring activity: A multi-wavelength study
Shashi. B. Pandey, Amit. K. Ror, A. J. Castro-Tirado +48
Context. This article presents a detailed multi-wavelength analysis of GRB 140304A at z = 5.282, having uncommon late-time flaring features. The aim is to study GRB 140304A and oth…
On the variation of solar coronal rotation using SDO/AIA observations
Jaidev Sharma, Brajesh Kumar, Anil K. Malik +1
We report on the variability of rotation periods of solar coronal layers with respect to temperature (or, height). For this purpose, we have used the observations from Atmospheric…
Multiwavelength Analysis of GRB 250101A: From Gamma-ray Prompt Emission to Optical Afterglow
Guowang Du, Yehao Cheng, Yuan-Pei Yang +15
The interaction between the relativistic jet and the circumburst medium produces a multiwavelength afterglow of a gamma-ray burst (GRBs). In this work, we present multiwavelength p…