Search Publications
The Magnetic Origin of Solar Campfires
Tiwari, Sanjiv K.; Cheung, Mark C. M.; Berghmans, David +4 more
Solar campfires are fine-scale heating events, recently observed by Extreme Ultraviolet Imager (EUI) on board Solar Orbiter. Here we use EUI 174 Å images, together with EUV images from Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly (AIA), and line-of-sight magnetograms from SDO/Helioseismic and Magnetic Imager (HMI) to investigate t…
The luminous red nova AT 2018bwo in NGC 45 and its binary yellow supergiant progenitor
Gehrz, Robert D.; Bond, Howard E.; Burdge, Kevin B. +12 more
Luminous red novae (LRNe) are astrophysical transients associated with the partial ejection of a binary system's common envelope shortly before its merger. Here we present the results of our photometric and spectroscopic follow-up campaign of AT 2018bwo (DLT 18x), a LRN discovered in NGC 45, and investigate its progenitor system using binary stell…
First Fermi-LAT Solar Flare Catalog
Troja, E.; Orlando, E.; Ajello, M. +82 more
We present the first Fermi-Large Area Telescope (LAT) solar flare catalog covering the 24th solar cycle. This catalog contains 45 Fermi-LAT solar flares (FLSFs) with emission in the γ-ray energy band (30 MeV-10 GeV) detected with a significance of ≥5σ over the years 2010-2018. A subsample containing 37 of these flares exhibits delayed emission bey…
3D dynamics of the Orion cloud complex. Discovery of coherent radial gas motions at the 100-pc scale
Meingast, Stefan; Alves, João; Großschedl, Josefa E. +1 more
We present the first study of the three-dimensional (3D) dynamics of the gas in the entire southern Orion cloud complex. We used the parallaxes and proper motions of young stellar objects (YSOs) from Gaia DR2 as a proxy for gas distance and proper motion, and the gas radial velocities from archival CO data, to compute the space motions of the diff…
Comprehensive Broadband X-Ray and Multiwavelength Study of Active Galactic Nuclei in 57 Local Luminous and Ultraluminous Infrared Galaxies Observed with NuSTAR and/or Swift/BAT
Imanishi, Masatoshi; Tanimoto, Atsushi; Ueda, Yoshihiro +4 more
We perform a systematic X-ray spectroscopic analysis of 57 local luminous and ultraluminous infrared galaxy systems (containing 84 individual galaxies) observed with the Nuclear Spectroscopic Telescope Array and/or Swift/BAT. Combining soft X-ray data obtained with Chandra, XMM-Newton, Suzaku, and/or Swift/XRT, we identify 40 hard (>10 keV) X-r…
Evidence of a Dwarf Galaxy Stream Populating the Inner Milky Way Halo
Malhan, Khyati; Ibata, Rodrigo A.; Martin, Nicolas F. +3 more
Stellar streams produced from dwarf galaxies provide direct evidence of the hierarchical formation of the Milky Way. Here, we present the first comprehensive study of the LMS-1 stellar stream, that we detect by searching for wide streams in the Gaia EDR3 data set using the STREAMFINDER algorithm. This stream was recently discovered by Yuan et al. …
Constraints on a mixed model of dark matter particles and primordial black holes from the galactic 511 keV line
Cai, Rong-Gen; Ding, Yu-Chen; Yang, Xing-Yu +1 more
The galactic 511 keV gamma-ray line has been observed since 1970's, and was identified as the result of electron-positron annihilation, but the origin of such positrons is still not clear. Apart from the astrophysical explanations, the possibilities that such positrons come from dark matter (DM) annihilation are also widely studied. Primordial bla…
Size and structures of disks around very low mass stars in the Taurus star-forming region
Pascucci, I.; Testi, L.; Scholz, A. +7 more
Context. The discovery of giant planets orbiting very low mass stars (VLMS) and the recent observed substructures in disks around VLMS is challenging planet formation models. Specifically, radial drift of dust particles is a catastrophic barrier in these disks, which prevents the formation of planetesimals and therefore planets.
Aims: We aim …
Low-redshift compact star-forming galaxies as analogues of high-redshift star-forming galaxies
Schaerer, D.; Thuan, T. X.; Izotov, Y. I. +3 more
We compare the relations among various integrated characteristics of ∼25 000 low-redshift (z ≲ 1.0) compact star-forming galaxies (CSFGs) from Data Release 16 (DR16) of the Sloan Digital Sky Survey and of high-redshift (z ≳ 1.5) star-forming galaxies (SFGs) with respect to oxygen abundances, stellar masses M⋆, far-UV absolute magnitudes…
Giant Planets, Tiny Stars: Producing Short-period Planets around White Dwarfs with the Eccentric Kozai-Lidov Mechanism
Gaudi, B. Scott; Naoz, Smadar; Stephan, Alexander P.
The recent discoveries of WD J091405.30+191412.25 (WD J0914 hereafter), a white dwarf (WD) likely accreting material from an ice-giant planet, and WD 1856+534 b (WD 1856 b hereafter), a Jupiter-sized planet transiting a WD, are the first direct evidence of giant planets orbiting WDs. However, for both systems, the observations indicate that the pl…