Search Publications
The Apparent Absence of Forward Scattering in the HD 53143 Debris Disk
Stark, Christopher C.; MacGregor, Meredith A.; Weinberger, Alycia J. +5 more
HD 53143 is a mature Sun-like star and host to a broad disk of dusty debris, including a cold outer ring of planetesimals near 90 au. Unlike most other inclined debris disks imaged at visible wavelengths, the cold disk around HD 53143 appears as disconnected "arcs" of material, with no forward-scattering side detected to date. We present new, deep…
Field Gradient Analysis Based on a Geometrical Approach
Dunlop, M.; Shen, C.
Using multi-point observations from a spacecraft constellation, the spatial gradients of measured physical quantities can be calculated, and thus other derived parameters for the plasma (e.g., current density, topology of magnetic field lines, and wave vectors) can also be calculated. In this research, a geometrical method based on integral theore…
SRG/eROSITA-triggered XMM-Newton observations of three Be/X-ray binaries in the LMC: Discovery of X-ray pulsations
Haberl, F.; Udalski, A.; Ducci, L. +11 more
Context. Using data from eROSITA, the soft X-ray instrument aboard Spectrum-Roentgen-Gamma (SRG), we report the discovery of two new hard transients, eRASSU J050810.4-660653 and eRASSt J044811.1-691318, in the Large Magellanic Cloud. We also report the detection of the Be/X-ray binary RX J0501.6-7034 in a bright state.
Aims: We initiated foll…
Will ALMA reveal the true core mass function of protoclusters?
Juvela, M.; Pelkonen, V. -M.; Haugbølle, T. +2 more
Characterizing pre-stellar cores in star-forming regions is an important step towards the validation of theoretical models of star formation. Due to their sub-arcsecond resolution, ALMA observations can potentially provide samples of pre-stellar cores up to distances of a few kpc, where regions of massive star formation can be targeted. However, t…
Unveiling the Initial Conditions of Open Star Cluster Formation
Hao, C. J.; Xu, Y.; Hou, L. G. +2 more
Open clusters (OCs) are infrequent survivors of embedded clusters gestated in molecular clouds. Up to now, little is known about the initial conditions for the formation of OCs. Here, we studied this issue using high-precision astrometric parameters provided by Gaia data release 3. The statistics show that the peculiar motion velocities of OCs var…
A Chandra X-ray study of millisecond pulsars in the globular cluster Omega Centauri: a correlation between spider pulsar companion mass and X-ray luminosity
Zhao, Jiaqi; Heinke, Craig O.
Millisecond pulsars (MSPs) are faint X-ray sources commonly observed in Galactic globular clusters (GCs). In this work, we investigate 18 MSPs newly found in the GC Omega Centauri (ω Cen) and search for their X-ray counterparts using Chandra observations with a total exposure time of 290.9 ks. We identify confident X-ray counterparts for 11 of the…
The Clustering Properties of AGNs/Quasars in CatWISE2020 Catalog
Tiwari, Prabhakar; Zhao, Gong-Bo; Nusser, Adi
We study the clustering properties of 1,307,530 AGNs/quasars in the CatWISE2020 catalog prepared using the Wide-field Infrared Survey Explorer and Near-Earth Object Wide-field Infrared Survey Explorer survey data. For angular moments ℓ ⪆ 10 (⪅18°) down to nonlinear scales, the results are in agreement with the standard ΛCDM cosmology, with a galax…
A GALEX view of the DA white dwarf population
Bergeron, P.; Wall, Renae E.; Kilic, Mukremin +1 more
We present a detailed model atmosphere analysis of 14001 DA white dwarfs from the Montreal White Dwarf Database with ultraviolet photometry from the GALEX mission. We use the 100 pc sample, where the extinction is negligible, to demonstrate that there are no major systematic differences between the best-fitting parameters derived from optical only…
Filaments in the OMC-3 cloud and uncertainties in estimates of filament profiles
Juvela, M.; Mannfors, E.
Context. Filamentary structures are an important part of star-forming interstellar clouds. The properties of filaments hold clues to their formation mechanisms and their role in the star-formation process.
Aims: We compare the properties of filaments in the Orion Molecular Cloud 3 (OMC-3), as seen in mid-infrared (MIR) absorption and far-infr…
Investigation of a small X-ray flaring event in NLS1 galaxy NGC 4051
Naik, Sachindra; Jana, Arghajit; Kumari, Neeraj +1 more
We performed a detailed broad-band spectral and timing analysis of a small flaring event of ~120 ks in the narrow-line Seyfert 1 galaxy NGC 4051 using simultaneous XMM-Newton and NuSTAR observations. The ~300 ks long NuSTAR observation and the overlapping XMM-Newton exposure were segregated into pre-flare, flare, and post-flare segments. During th…