Search Publications
A Markedly Expanded Sample of Candidate X-Ray-emitting Isolated Neutron Stars
Anderson, Scott F.; Agüeros, Marcel A.; Demasi, Sebastian
The current sample of 12 radio-quiet isolated neutron stars that emit strongly in X-rays (XINSs) is both small and heterogeneous, limiting its usefulness for understanding the physics of neutron star atmospheres and cooling rates and for constraining the equation of state of neutron degenerate matter. Utilizing the ROSAT 1RXS and 2RXS data sets, i…
Acceleration and Release of Solar Energetic Particles Associated with a Coronal Shock on 2021 September 28 Observed by Four Spacecraft
Lugaz, Noé; Zhuang, Bin; Chrysaphi, Nicolina +5 more
The main driver of the acceleration of solar energetic particles (SEPs) is believed to be shocks driven by coronal mass ejections. Extreme-ultraviolet (EUV) waves are thought to be the propagating footprint of the shock on the solar surface. One of the key questions in SEP research is the timing of the SEP release with respect to the time when the…
Comprehensive Synthesis of Magnetic Tornado: Cospatial Incidence of Chromospheric Swirls and Extreme-ultraviolet Brightening
Yokoyama, Takaaki; Bose, Souvik; Kuniyoshi, Hidetaka
Magnetic tornadoes, characterized as impulsive Alfvén waves initiated by photospheric vortices in intergranular lanes, are considered efficient energy channels to the corona. Despite their acknowledged importance for solar coronal heating, their observational counterparts from the corona have not been well understood. To address this issue, we use…
From Chromospheric Evaporation to Coronal Rain: An Investigation of the Mass and Energy Cycle of a Flare
Antolin, Patrick; Şahin, Seray
Chromospheric evaporation (CE) and coronal rain (CR) represent two crucial phenomena encompassing the circulation of mass and energy during solar flares. While CE marks the start of the hot inflow into the flaring loop, CR marks the end, indicating the outflow in the form of cool and dense condensations. With the Interface Region Imaging Spectrogr…
First Detection of CO Isotopologues in a High-redshift Main-sequence Galaxy: Evidence of a Top-heavy Stellar Initial Mass Function
Fu, Xiaoting; Ivison, R. J.; Zhang, Zhi-Yu +5 more
Recent observations and theories have presented a strong challenge to the universality of the stellar initial mass function (IMF) in extreme environments. A notable example has been found for starburst conditions, where evidence favors a top-heavy IMF, i.e., there is a bias toward massive stars compared to the IMF that is responsible for the stell…
The ALMA View of Positive Black Hole Feedback in the Dwarf Galaxy Henize 2–10
Reines, Amy E.; Gim, Hansung B.
Henize 2–10 is a dwarf starburst galaxy hosting a ∼106 M ⊙ black hole (BH) that is driving an ionized outflow and triggering star formation within the central ∼100 pc of the galaxy. Here, we present Atacama Large Millimeter/submillimeter Array continuum observations from 99 to 340 GHz, as well as spectral line observations of…
Prominent Mid-infrared Excess of the Dwarf Planet (136472) Makemake Discovered by JWST/MIRI Indicates Ongoing Activity
Pál, András; Lellouch, Emmanuel; Moór, Attila +18 more
We report on the discovery of a very prominent mid-infrared (18–25 µm) excess associated with the trans-Neptunian dwarf planet (136472) Makemake. The excess, detected by the Mid-Infrared Instrument of the James Webb Space Telescope, along with previous measurements from the Spitzer and Herschel space telescopes, indicates the occurrence of t…
A Numerical Study of the Effects of a Corotating Interaction Region on Cosmic-Ray Transport. II. Features of Cosmic-Ray Composition and Rigidity
Luo, Xi; Shen, Fang; Zhang, Ming +1 more
We continue the numerical modeling of a corotating interaction region (CIR) and the effects it has on solar-rotational recurrent variations of galactic cosmic rays (GCRs). A magnetohydrodynamic model is adapted to simulate the background solar wind plasma with a CIR structure in the inner heliosphere, which is incorporated into a comprehensive Par…
CHAOS. VIII. Far-ultraviolet Spectra of M101 and the Impact of Wolf–Rayet Stars
Skillman, Evan D.; Chisholm, John; Erb, Dawn K. +8 more
We investigate the stellar and nebular properties of nine H II regions in the spiral galaxy M101 with far-ultraviolet (FUV; ∼900–2000 Å) and optical (∼3200–10,000 Å) spectra. We detect significant C III] λλ1907,1909 nebular emission in seven regions, but O III] λ1666 only in the lowest-metallicity region. We produce new analytic functions of the c…
The High-mass X-Ray Binary Luminosity Functions of Dwarf Galaxies
Greene, Jenny E.; Goulding, Andy D.; Lehmer, Bret D. +2 more
Drawing from the Chandra archive and using a carefully selected set of nearby dwarf galaxies, we present a calibrated high-mass X-ray binary (HMXB) luminosity function in the low-mass galaxy regime and search for an already hinted at dependence on metallicity. Our study introduces a new sample of local dwarf galaxies (D < 12.5 Mpc and M *<…