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Related papers: J-VAR: the northern variable sky in 7 filters -- F…

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This paper combines data from the three preceding papers in order to analyze the multi-waveband variability and spectral energy distribution of the Seyfert~1 galaxy NGC~4151 during the December 1993 monitoring campaign. The source, which…

Astrophysics · Physics 2009-10-28 R. A. Edelson et al

We analyze results from the first eighteen months of monthly sub-mm monitoring of eight star-forming regions in the JCMT Transient Survey. In our search for stochastic variability in 1643 bright peaks, only the previously identified source,…

To search for optical variability on a wide range of timescales, we have carried out photometric monitoring of two flat spectrum radio quasars, 3C 454.3 and 3C 279, plus one BL Lac, S5 0716+714, all of which have been exhibiting remarkably…

The Javalambre-Physics of the Accelerating Universe Astrophysical Survey (J-PAS) is an ongoing survey mapping thousands of square degrees in the Northern Hemisphere using 56 narrow-band filters, delivering IFU-like photometric data well…

In the present paper we aim to validate a methodology designed to extract the Halpha emission line flux from J-PLUS photometric data. J-PLUS is a multi narrow-band filter survey carried out with the 2 deg2 field of view T80Cam camera,…

Variability detected in galaxies is usually attributed to their active galactic nuclei (AGNs). While all AGNs are intrinsically variable, the AGN unification model predicts that type~2 AGNs rarely vary because their engines are blocked by…

Astrophysics of Galaxies · Physics 2026-02-17 Bangzheng Sun , Haojing Yan , Wei Leong Tee , Feige Wang

We report on I band photometric observations of 21 stars with spectral types between M8 and L4 made using the Isaac Newton Telescope. The total amount of time for observations which had a cadence of <2.3 mins was 58.5 hrs, with additional…

Solar and Stellar Astrophysics · Physics 2015-09-09 Gavin Ramsay , Pasi Hakala , J Gerry Doyle

We show that a large-area imaging survey using narrow-band filters could detect quasars in sufficiently high number densities, and with more than sufficient accuracy in their photometric redshifts, to turn them into suitable tracers of…

We studied the six gamma-ray-detected Narrow Line Seyfert 1 (NLSy1) galaxies using the hard X-ray observations from Nuclear Spectroscopic Telescope Array (NuSTAR) and optical g- \& r-band from Zwicky Transient Facility (ZTF). The X-ray…

High Energy Astrophysical Phenomena · Physics 2025-12-16 Suvas Chandra Chaudhary , Raj Prince , Brian van Soelen , Pieter Meintjes

We present the first full catalog and science results for the NuSTAR serendipitous survey. The catalog incorporates data taken during the first 40 months of NuSTAR operation, which provide ~20Ms of effective exposure time over 331 fields,…

Though there has been a significant amount of work investigating the early stages of low-mass star formation in recent years, the evolution of the mass assembly rate onto the central protostar remains largely unconstrained. Examining in…

Context. In modern astronomy, machine learning has proved to be efficient and effective to mine the big data from the newesttelescopes. Spectral surveys enable us to characterize millions of objects, while long exposure time observations…

We present the J and H-band source catalog covering the AKARI North Ecliptic Pole field. Filling the gap between the optical data from other follow-up observations and mid-infrared (MIR) data from AKARI, our near-infrared (NIR) data…

Astrophysics of Galaxies · Physics 2015-03-11 Yiseul Jeon , Myungshin Im , Eugene Kang , Hyung Mok Lee , Hideo Matsuhara

We present variability and multi-wavelength photometric information for the 933 known quasars in the QUEST Variability Survey. These quasars are grouped into variable and non-variable populations based on measured variability confidence…

Astrophysics · Physics 2008-11-26 Adam W. Rengstorf , Robert J. Brunner , Brian C. Wilhite

A comprehensive search for variable and transient radio sources has been conducted using ~55,000 snapshot images of the FIRST survey. We present an analysis leading to the discovery of 1,627 variable and transient objects down to mJy levels…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Nithyanandan Thyagarajan , David J. Helfand , Richard L. White , Robert H. Becker

Robust fast methods to classify variable light curves in large sky surveys are becoming increasingly important. While it is relatively straightforward to identify common periodic stars and particular transient events (supernovae, novae,…

In this document, we summarize the main capabilities of the James Webb Space Telescope (JWST) for performing observations of Mars. The distinctive vantage point of JWST at the Sun-Earth Lagrange point (L2) will allow sampling the full…

This paper is the third in the series of papers published on near-infrared (NIR) stellar spectral library by Ranade et al. (2004 & 2007). The observations were carried out with 1.2 meter Gurushikhar Infrared Telescope (GIRT), at Mt. Abu,…

Astrophysics · Physics 2007-10-01 Arvind C. Ranade , N. M. Ashok , Harinder P. Singh , Ranjan Gupta

James Webb Space Telescope (JWST) has revealed a population of red and compact sources at $z \gtrsim 5$ known as ``Little Red Dots'' (LRDs) that are likely active galactic nuclei (AGNs). Here we present a comprehensive study of the…

Astrophysics of Galaxies · Physics 2025-04-18 Zijian Zhang , Linhua Jiang , Weiyang Liu , Luis C. Ho