Search Publications
Connection among environment, cloud-cloud collision speed, and star formation activity in the strongly barred galaxy NGC 1300
Ohta, Kouji; Maeda, Fumiya; Fujimoto, Yusuke +1 more
Cloud-cloud collision (CCC) has been suggested as a mechanism to induce massive star formation. Recent simulations suggest that a CCC speed is different among galactic-scale environments, which is responsible for observed differences in star formation activity. In particular, a high-speed CCC is proposed as a cause of star formation suppression in…
X-ray analysis of SDSS J165202.60+172852.4, an obscured quasar with outflows at peak galaxy formation epoch
Hamann, Fred; Veilleux, Sylvain; Goulding, Andy D. +4 more
We report on deep XMM-Newton and NuSTAR observations of the high redshift, z = 2.94, extremely red quasar (ERQ), SDSS J165202.60+172852.4, with known galactic ionized outflows detected via spatially resolved [O III] emission lines. X-ray observations allow us to directly probe the accretion disc luminosity and the geometry and scale of the circumn…
NGTS clusters survey - III. A low-mass eclipsing binary in the Blanco 1 open cluster spanning the fully convective boundary
Triaud, Amaury H. M. J.; Wheatley, Peter J.; Bayliss, Daniel +27 more
We present the discovery and characterization of an eclipsing binary identified by the Next Generation Transit Survey in the ~115-Myr-old Blanco 1 open cluster. NGTS J0002-29 comprises three M dwarfs: a short-period binary and a companion in a wider orbit. This system is the first well-characterized, low-mass eclipsing binary in Blanco 1. With a l…
Progenitor mass constraints for the type Ib intermediate-luminosity SN 2015ap and the highly extinguished SN 2016bau
Filippenko, Alexei V.; Pandey, S. B.; Buckley, David A. H. +21 more
Photometric and spectroscopic analyses of the intermediate-luminosity Type Ib supernova (SN) 2015ap and of the heavily reddened Type Ib SN 2016bau are discussed. Photometric properties of the two SNe, such as colour evolution, bolometric luminosity, photospheric radius, temperature, and velocity evolution, are also constrained. The ejecta mass, sy…
Impact of magnetic activity on inferred stellar properties of main-sequence Sun-like stars
Chaplin, William J.; Basu, Sarbani; Miglio, Andrea +3 more
The oscillation frequencies observed in Sun-like stars are susceptible to being shifted by magnetic activity effects. The measured shifts depend on a complex relationship involving the mode type, the field strength, and spatial distribution of activity, as well as the inclination angle of the star. Evidence of these shifts is also present in frequ…
Modelling heterogeneous dust particles: an application to cometary polarization
Halder, Prithish; Ganesh, Shashikiran
In this work, we introduce a comet dust model that incorporates multiple dust morphologies along with inhomogeneous mixture of silicate minerals and carbonaceous materials under power-law size distribution, to replicate the standard polarization-phase curve observed in several comets in the narrow-band continuum. Following the results from Rosetta…
Deep Chandra observations of diffuse hot plasma in M83
Wang, Q. Daniel; Ji, Li; Bogdán, Ákos +1 more
It is widely believed that galaxy formation and evolution is regulated by stellar mechanical feedback in forms of fast stellar winds and supernova explosions. However, the coupling of this feedback with the interstellar medium remains poorly understood. We examine how the coupling may be traced by diffuse soft X-ray emission in M83 - a nearby face…
Electron temperature fluctuations in Seyfert galaxies
Riffel, Rogemar A.; Esteban, César; Dors, Oli L. +1 more
We use Gemini GMOS-IFU observations of three luminous nearby Seyfert galaxies (Mrk 79, Mrk 348, and Mrk 607) to estimate the electron temperature (Te) fluctuations in the inner 0.4-1.1 kpc region of these galaxies. Based on Te determinations through the [O III]λ5007/λ4363 emission line ratio of each spaxel, temperature variat…
Search for dormant black holes in ellipsoidal variables - III. The OGLE BULGE short-period sample
Gomel, Roy; Faigler, Simchon; Mazeh, Tsevi +1 more
This is the third of a series of papers that presents an algorithm to search for close binaries with massive, possibly compact, unseen secondaries. The detection of such a binary is based on identifying a star that displays a large ellipsoidal periodic modulation, induced by tidal interaction with its companion. In the second paper of the series, …
Vibrationally excited HC3N emission in NGC 1068: tracing the recent star formation in the starburst ring
Martín-Pintado, J.; García-Burillo, S.; González-Alfonso, E. +5 more
Using the ALMA data, we have studied the HC3N and continuum emission in the starburst pseudo-ring (SB pseudo-ring) and the circumnuclear disc (CND) of the SB/active galactic nucleus (AGN) composite galaxy NGC 1068. We have detected emission from vibrationally excited HC3N (HC3N*) only towards one star-forming regio…