Search Publications
XMM-Newton view of the shock heating in an early merging cluster, CIZA J1358.9-4750
Sato, Kosuke; Nakazawa, Kazuhiro; Gu, Liyi +10 more
CIZA J1358.9-4750 is a nearby galaxy cluster in the early phase of a major merger. The two-dimensional temperature map using XMM-Newton EPIC-PN observation confirms the existence of a high-temperature region, which we call the "hot region," in the "bridge region" connecting the two clusters. The ~500 kpc wide region between the south-east and nort…
Very late-time spectroscopy of SN 2009ip: Constraints on the ongoing Hα emission
Prieto, Jose L.; Dessart, Luc; Pessi, Thallis
Context. The peculiar supernova (SN) 2009ip was an ambiguous event that placed many questions on its true origin. Here, we present very late-time spectroscopic and photometric observations of SN 2009ip, obtained 9 years (3274 days) after the 2012B outburst.
Aims: We analyze the Hα emission still present in the very late-time spectrum of SN 20…
Alignment and rotational disruption of dust grains in the Galactic Centre revealed by polarized dust emission
Hoang, Thiem; Akshaya, M. S.
We study the alignment and rotational disruption of dust grains at the centre of our Galaxy using polarized thermal dust emission observed by SOFIA/HAWC+ and JCMT/SCUPOL at 53, 216, and 850 µm. We analysed the relationship between the observed polarization degree with total emission intensity, dust temperature, gas column density, and polarization…
Varstrometry selected radio-loud candidates of dual and off-nucleus quasars at sub-kpc scales
Wang, Jun-Xian; Gu, Min-Feng; Wang, Hao-Chen +1 more
Dual super massive black holes (SMBHs) at sub-kpc to kpc scales, the product of galaxy mergers, are progenitors of eventually coalescing binary SMBHs. If both or one of the dual SMBHs are accreting, they may appear as dual AGNs or off-nucleus AGNs. Studying such systems is essential to learn the dynamical evolution of binary SMBHs as well as the p…
Constraints on galaxy formation from the cosmic-far-infrared-background - optical-imaging cross-correlation using Herschel and UNIONS
McConnachie, Alan W.; Cuillandre, Jean-Charles; Gwyn, Stephen +11 more
Using Herschel-SPIRE imaging and the Canada-France Imaging Survey (CFIS) Low Surface Brightness data products from the Ultraviolet Near-Infrared Optical Northern Survey (UNIONS), we present a cross-correlation between the cosmic far-infrared background and cosmic optical background fluctuations. The cross-spectrum is measured for two cases: all ga…
Magnetic Field Extrapolation in Active Region Well Comparable to Observations in Multiple Layers
Zhu, Xiaoshuai; Li, Hui; Su, Yang +4 more
Magnetic field extrapolation is a fundamental tool to reconstruct the three-dimensional magnetic field above the solar photosphere. However, the prevalently used force-free field model might not be applicable in the lower atmosphere with non-negligible plasma β, where the crucial process of flux rope formation and evolution could happen. In this w…
Revealing the Milky Way's most recent major merger with a Gaia EDR3 catalogue of machine-learned line-of-sight velocities
Lisanti, Mariangela; Dropulic, Adriana; Ostdiek, Bryan +1 more
Machine learning can play a powerful role in inferring missing line-of-sight velocities from astrometry in surveys such as Gaia. In this paper, we apply a neural network to Gaia Early Data Release 3 (EDR3) and obtain line-of-sight velocities and associated uncertainties for ~92 million stars. The network, which takes as input a star's parallax, an…
Star-crossed Lovers DI Tau A and B: Orbit Characterization and Physical Properties Determination
Tang, Shih-Yun; Uyama, Taichi; Johns-Krull, Christopher M. +5 more
The stellar companion to the weak-line T Tauri star DI Tau A was first discovered by the lunar occultation technique in 1989 and was subsequently confirmed by a speckle imaging observation in 1991. It has not been detected since, despite being targeted by five different studies that used a variety of methods and spanned more than 20 yr. Here, we r…
Detecting low-mass perturbers in cluster lenses using curved arc bases
Dvorkin, Cora; Birrer, Simon; Natarajan, Priyamvada +1 more
Strong gravitationally lensed arcs produced by galaxy clusters have been observationally detected for several decades now. These strong lensing constraints provided high-fidelity mass models for cluster lenses that include substructure down to $10^{9{-}10}\, \mathrm{M}_\odot$. Optimizing lens models, where the cluster mass distribution is modelled…
The Age-Metallicity Relation in the Solar Neighbourhood
Plevne, Olcay; Ak, Serap; Döner, Sibel +1 more
Age-metallicity relation for the Galactic disc is a crucial tool and is used to constrain the Galactic chemical evolution models. We investigated the age-metallicity relation of the Galactic disc using the red giant branch stars in the Solar neighbourhood. The data cover the Galactocentric radius of $7\leq R_{\rm gc} (\rm kpc) \leq9.5$, but extend…