Search Publications
Missions
Journals
Publication Years
High-contrast detection of exoplanets with a kernel-nuller at the VLTI
Ireland, Michael J.; Martinache, Frantz; N'Diaye, Mamadou +5 more
Context. The conventional approach to direct imaging is to use a single aperture coronagraph with wavefront correction via extreme adaptive optics (AO). Such systems are limited to observing beyond an inner working angle (IWA) of a few λ/D. Nulling interferometry with two or more apertures will enable detections of companions at separations at and…
The universality of power law slopes in the solar photosphere and transition region observed with HMI and IRIS
Aschwanden, Markus J.; Nhalil, Nived Vilangot
We compare the size distributions of self-organized criticality (SOC) systems in the solar photosphere and the transition region, using magnetogram data from Helioseismic and Magnetic Imager (HMI) and Interface Region Imaging Spectrograph (IRIS) data. For each dataset we fit a combination of a Gaussian and a power law size distribution function, w…
Testing ultralow amplitude Cepheid candidates in the Galactic disk by TESS and Gaia
Bódi, Attila; Szabó, Róbert; Molnár, László +1 more
Ultralow amplitude (ULA) and strange mode Cepheids are thought to be pulsating variable stars that are near to or are at the edges of the classical instability strip. Until now, a few dozen such variable star candidates have been found both in the Large Magellanic Cloud and the Milky Way. For the present work, we studied six ULA Cepheid candidates…
The SPHEREx Target List of Ice Sources (SPLICES)
Kang, Miju; Lee, Jeong-Eun; Lee, Ho-Gyu +16 more
One of the primary objectives of the SPHEREx mission is to understand the origin of molecules such as H2O, CO2, and other volatile compounds at the early stages of planetary system formation. Because the vast majority of these compounds-typically exceeding 95%-exist in the solid phase rather than the gaseous phase in the syst…
A Revised Graduated Cylindrical Shell Model and its Application to a Prominence Eruption
Zhang, Qing-Min; Hou, Zhen-Yong; Bai, Xian-Yong
In this paper, the well-known graduated cylindrical shell (GCS) model is slightly revised by introducing longitudinal and latitudinal deflections of prominences originating from active regions (ARs). Subsequently, it is applied to the three-dimensional (3D) reconstruction of an eruptive prominence in AR 13110, which produced an M1.7 class flare an…
Search for particle acceleration in two massive Wolf-Rayet stars using uGMRT observations
Tej, Anandmayee; del Palacio, Santiago; Saha, Anindya +4 more
Large wind kinetic power of Wolf-Rayet (WR) stars make them ideal targets in low radio frequencies to search for non-thermal emission due to relativistic particle acceleration. In this paper, we present observations of two WR stars, WR 114 and WR 142, in Band 4 (550-950 MHz) and Band 5 (1050-1450 MHz) using the upgraded Giant Meterwave Radio Teles…
New Method to Detect and Characterize Active Be Star Candidates in Open Clusters
Granada, Anahí; Eenmäe, Tõnis; Ghoreyshi, Maziar R. +1 more
With the aim of better understanding the physical conditions under which Be stars form and evolve, it is imperative to further investigate whether poorly studied young open clusters host Be stars. In this work, we explain how data from Gaia DR2 and DR3 can be combined to recover and characterize active Be stars in open clusters. We test our method…
New transient ULX candidate in NGC 4254: evidence of circumbinary disc?
Allak, Sinan
This paper presents the identification of a new transient ultraluminous X-ray source (ULX) candidate (ULX-3) with reaching a peak luminosity of ~4 × 1039 erg s-1 in NGC 4254 by using archival Chandra, Swift/X-Ray Telescope, Hubble Space Telescope, and JWST observations. From precise astrometric calculations, unique optical, n…
The Study of X-Ray Spectrum of Coma Galaxy Cluster
Pulatova, N.; Tugay, A.; Zadorozhna, L. +4 more
The X-ray spectrum of the Coma galaxy cluster was studied using the data from the XMM-Newton observatory. We combined 7 observations performed with the MOS camera of XMM-Newton in the 40' × 40' region centered at the Coma cluster. The analyzed observations were performed in 2000-2005 and have a total duration of 196ksec. We focus on the analysis o…
Exploring the environment, magnetic fields, and feedback effects of massive high-redshift galaxies with [C II]
Knudsen, K. K.; König, S.; Gullberg, B. +3 more
Context. Massive galaxies are expected to grow through different transformative evolutionary phases. High-redshift starburst galaxies and quasars are thought to be such phases and thus provide insight into galaxy evolution. Several physical mechanisms are predicted to play an important role in driving these phases; for example, interaction with co…