• Characterizing Optical Variability of OJ 287 in 2016–2017 

  Gupta, Alok C. et al.; Gaur, Haritma; Pandey, A. (The Astronomical Journal, 2019-03)

  We report on a recent multiband optical photometric and polarimetric observational campaign of the blazar OJ 287 that was carried out during 2016 September–2017 December. We employed nine telescopes in Bulgaria, China, ...
• Aerosol and pollutant characteristics in Delhi during a winter research campaign 

  Dumka, Umesh C. et al. (Environmental Science and Pollution Research, 2019-02)

  Urban areas in developing countries are major sources of carbonaceous aerosols and air pollutants, pointing out the need for a detailed assessment of their levels and origin close to the source. A multi-instrument research ...
• Optical Flux and Spectral Variability of the TeV Blazar PG 1553+113 

  Pandey, Ashwani; Gupta, Alok C.; Wiita, Paul J.; Tiwari, S. N. (The Astrophysical Journal, 2019-02)

  We present the results of our optical (VRI) observations of the TeV blazar PG 1553+113 over eight nights in 2016 April. We monitored the blazar quasi-simultaneously in V and R bands each night and examined the light ...
• General relativistic two-temperature accretion solutions for spherical flows around black holes 

  Sarkar, Shilpa; Chattopadhyay, Indranil (International Journal of Modern Physics D, 2019-02)

  Matter falling onto black holes is hot, fully ionized and has to be necessarily transonic. Since the electrons are responsible for radiative cooling via processes like synchrotron, bremsstrahlung and inverse-Compton, the ...
• Intra-night optical monitoring of three γ -ray detected narrow-line Seyfert 1 galaxies 

  Ojha, Vineet; Krishna, Gopal-; Chand, Hum (Monthly notices of the Royal Astronomical Society, 2019-03)

  For three radio-loud γ -ray detected narrow-line Seyfert 1 (γ -ray NLSy1) galaxies, we report optical variability on intra-night and/or week-like time-scales, based on five ≥ 3 h long monitoring sessions for each galaxy. ...
• Atmospheric dynamics associated with exceptionally dusty conditions over the eastern Mediterranean and Greece in March 2018 

  Kaskaoutis, D.G.; Dumka, U.C. (Atmospheric Research, Elsevier, 2019-04)

  This study examines the atmospheric dynamics that facilitated frequent and intense dust storms over the eastern Mediterranean in March 2018 via the synergy of satellite observations, ground-based measurements and reanalysis. ...
• A multiwavelength view of a classical T Tauri star CV Cha 

  Pandey, Jeewan Chandra; Karmakar, Subhajeet; Joshi, Arti; Sharma, Saurabh; Pandey, Shashi Bhushan; Pandey, Anil Kumar (Research in Astronomy and Astrophysics, 2019-01)

  Using long-term optical, ultraviolet (UV) and X-ray data, we present a study of a classical T Tauri star CV Cha. The V -band light curve obtained from the All Sky Automated Survey (ASAS) shows short as well as long-term ...
• On the Differential Rotation of Stars. 

  Savanov, I. S.; Dmitrienko, E. S.; Pandey, J. C.; Karmakar, S. (Astrophysical Bulletin, 2018-10)

  We discuss methods for analyzing the observational manifestations of differential rotation (DR). Based on the literary sources and our estimates (for 4 cool dwarfs), a list containing 75 stars was compiled. Using an ...
• Effects of Monsoon, Shamal and Levar winds on dust accumulation over the Arabian Sea during summer – The July 2016 case. 

  Rashki, A. et al.; Dumka, U. C. (Aeolian Research, Elsevier, 2019-02)

  This study examines the atmospheric circulation patterns that are associated with contrasting wind regimes, desert dust outflows and accumulation of dust over the Arabian Sea in the summer season. The examined period is ...
• Mass function and dynamical study of the open clusters Berkeley 24 and Czernik 27 using ground based imaging and Gaia astrometry. 

  Bisht, D.; Yadav, R. K. S. (Monthly Notices of the Royal Astronomical Society, 2019-01)

  We present a UBVI photometric study of the open clusters Berkeley 24 (Be 24) and Czernik 27 (Cz 27). The radii of the clusters are determined as 2. 7 and 2. 3 for Be 24 and Cz 27, respectively. We use the Gaia Data ...
• The radial distribution of blue stragglers in Galactic globular cluster NGC 6656 − clues to the dynamical status. 

  Singh, Gaurav; Yadav, R. K. S. (Monthly notices of the Royal Astronomical Society, 2019-02)

  We present the dynamical status of the Galactic globular cluster NGC 6656 using the spatial distribution of blue straggler stars (BSSs). A combination of multi-wavelength high-resolution space- and ground-based data are ...
• Radiation driving and heating of general relativistic jets under a Compton-scattering regime 

  Vyas, Mukesh K.; Chattopadhyay, Indranil (Monthly notices of the royal astronomical society, 2019-01)

  Interaction of intense radiation from the underlying accretion disc with a steady, generalrelativistic jet is studied. The radiation field imparts momentum as well as energy to the outflowing jet under Compton scattering. ...
• Elevated Black Carbon Concentrations and Atmospheric Pollution around Singrauli Coal-Fired Thermal Power Plants (India) Using Ground and Satellite Data. 

  Singh, Ramesh P.; Kumar, Sarvan; Singh, Abhay K. (International journal of environmental research and public health., 2018-11)

  The tropospheric NO2 concentration from OMI AURA always shows high concentrations of NO2 at a few locations in India, one of the high concentrations of NO2 hotspots is associated with the locations of seven coal-fired ...
• Low-frequency View of GW170817/GRB 170817A with the Giant Metrewave Radio Telescope. 

  Resmi, L. et al.; Misra, K. (Astrophysical journal, 2018-11)

  The short gamma-ray burst (GRB) 170817A was the first GRB associated with a gravitational-wave event. Due to the exceptionally low luminosity of the prompt γ-ray and the afterglow emission, the origin of both radiation ...
• Authenticating the Presence of a Relativistic Massive Black Hole Binary in OJ 287 Using Its General Relativity Centenary Flare: Improved Orbital Parameters. 

  Dey, Lankeswar et al.; Gopinathan, M.; Joshi, A.; Pandey, J. C. (Astrophysical journal, 2018-10)

  Results from regular monitoring of relativistic compact binaries like PSR 1913+16 are consistent with the dominant (quadrupole) order emission of gravitational waves (GWs). We show that observations associated with the ...
• Stochastic Modeling of Multiwavelength Variability of the Classical BL Lac Object OJ 287 on Timescales Ranging from Decades to Hours. 

  Goyal, A. et al.; Joshi, A.; Gopinathan, M.; Pandey, J. C. (Astrophysical journal, 2018-08)

  We present the results of our power spectral density analysis for the BL Lac object OJ 287, utilizing the FermiLAT survey at high-energy γ-rays, Swift-XRT in X-rays, several ground-based telescopes and the Kepler satellite in ...
• Activity of Young Dwarfs with Planetary Systems: EPIC 211901114 and K2–33. 

  Savanov, S.; Dmitrienko, E. S.; Karmakar, S.; Pandey, J. C. (Astronomy reports, 2018-08)

  The results of an analysis of the activity of the young stars with planetary systems EPIC 211901114 and K2–33 based on observational data obtained over 70 days with the Kepler Space Telescope are presented. The rotation ...
• Year-long variability of the fossil fuel and wood burning black carbon components at a rural site in southern Delhi outskirts 

  Dumka, U. C. et al.; Kumar, S. (Atmospheric research, Elsevier, 2019-02)

  This study examines year-long (April 2015 – March 2016) measurements of black carbon (BC) concentrations acquired with a 7-wavelength Aethalometer (ΑΕ-42) at Panchgaon, in the southern Delhi outskirts. We assess the ...
• Assessment of biomass burning and fossil fuel contribution to black carbon concentrations in Delhi during winter. 

  Dumka, U. C. et al.; Singh, N. (Atmospheric Environment, Elsevier, 2018-12)

  This study aims to assess the contribution of fossil-fuel combustion (BCff) and biomass (or wood) burning (BCwb) to wintertime black carbon (BC) concentrations in Delhi using the “Aethalometer model” approach. Continuous ...
• A study of a long duration B9 flare-CME event and associated shock. 

  Chandra, R. et al.; Uddin, W. (Advances in Space research, Elsevier, 2017-10)

  We present and discuss here the observations of a small long duration GOES B-class flare associated with a quiescent filament eruption, a global EUV wave and a CME on 2011 May 11. The event was well observed by the Solar ...

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