Search Publications
Compton-thick AGN in the NuSTAR Era. VIII. A joint NuSTAR-XMM-Newton Monitoring of the Changing-look Compton-thick AGN NGC 1358
Pozzi, F.; Buchner, J.; Feltre, A. +18 more
We present the multi-epoch monitoring with NuSTAR and XMM-Newton of NGC 1358, a nearby Seyfert 2 galaxy whose properties made it a promising candidate X-ray changing-look active galactic nucleus (AGN), i.e., a source whose column density could transition from its 2017 Compton-thick (having LOS hydrogen column density N H,LOS > 10
Extragalactic Magnetism with SOFIA (SALSA Legacy Program). III. First Data Release and On-the-fly Polarization Mapping Characterization
Beckman, John E.; Reach, William T.; Dale, Daniel A. +17 more
We describe the data processing of the Survey on extragALactic magnetiSm with SOFIA (SALSA Legacy Program). This first data release presents 33% (51.34 hr out of 155.7 hr, including overheads) of the total awarded time from 2020 January to 2021 December. Our observations were performed using the newly implemented on-the-fly mapping (OTFMAP) techni…
Additional Evidence for a Pulsar Wind Nebula in the Heart of SN 1987A from Multiepoch X-Ray Data and MHD Modeling
Greco, Emanuele; Vink, Jacco; Miceli, Marco +9 more
Since the day of its explosion, supernova (SN) 1987A has been closely monitored to study its evolution and to detect its central compact relic. In fact, the formation of a neutron star is strongly supported by the detection of neutrinos from the SN. However, besides the detection in the Atacama Large Millimeter/submillimeter Array (ALMA) data of a…
A Coronal Mass Ejection and Magnetic Ejecta Observed In Situ by STEREO-A and Wind at 55° Angular Separation
Lugaz, Noé; Zhuang, Bin; Scolini, Camilla +8 more
We present an analysis of in situ and remote-sensing measurements of a coronal mass ejection (CME) that erupted on 2021 February 20 and impacted both the Solar TErrestrial RElations Observatory (STEREO)-A and the Wind spacecraft, which were separated longitudinally by 55°. Measurements on 2021 February 24 at both spacecraft are consistent with the…
Toward Improved Understanding of Magnetic Fields Participating in Solar Flares: Statistical Analysis of Magnetic Fields within Flare Ribbons
Savcheva, Antonia; Kazachenko, Maria D.; Lynch, Benjamin J. +2 more
Violent solar flares and coronal mass ejections (CMEs) are magnetic phenomena. However, how magnetic fields reconnecting in the flare differ from nonflaring magnetic fields remains unclear owing to the lack of studies of the flare magnetic properties. Here we present a first statistical study of flaring (highlighted by flare ribbons) vector magnet…
Solar Flare Heating with Turbulent Suppression of Thermal Conduction
Gordon Emslie, A.; Kerr, Graham S.; Allred, Joel C.
During solar flares, plasma is typically heated to very high temperatures, and the resulting redistribution of energy via thermal conduction is a primary mechanism transporting energy throughout the flaring solar atmosphere. The thermal flux is usually modeled using Spitzer's theory, which is based on local Coulomb collisions between the electrons…
Expanding Bipolar X-Ray Structure After the 2006 Eruption of RS Oph
Mukai, K.; Sokoloski, J. L.; Luna, G. J. M. +2 more
We report on the detection and analysis of extended X-ray emission by the Chandra X-ray Observatory stemming from the 2006 eruption of the recurrent nova RS Oph. The extended emission was detected 1254 and 1927 days after the start of the 2006 eruption and is consistent with a bipolar flow oriented in the East-West direction of the sky with openin…
Quasars with Proper Motions and the Link to Double and Multiple AGNs
Secrest, Nathan J.; Makarov, Valeri V.
Gaia used a large sample of photometrically selected active galactic nuclei (AGNs) and quasars to remove the residual spin of its global proper motion system in order to achieve a maximally inertial reference frame. A small fraction of these reference objects have statistically significant astrometric proper motions in Gaia EDR3. We compile a sour…
Mixing Interstellar Clouds Surrounding the Sun
Zank, Gary P.; Redfield, Seth; Winslow, Réka M. +9 more
On its journey through the Galaxy, the Sun passes through diverse regions of the interstellar medium. High-resolution spectroscopic measurements of interstellar absorption lines in spectra of nearby stars show absorption components from more than a dozen warm partially ionized clouds within 15 pc of the Sun. The two nearest clouds-the Local Inters…
Kepler-167e as a Probe of the Formation Histories of Cold Giants with Inner Super-Earths
Knutson, Heather A.; Fulton, Benjamin J.; Howard, Andrew W. +6 more
The observed correlation between outer giant planets and inner super-Earths is emerging as an important constraint on planet formation theories. In this study, we focus on Kepler-167, which is currently the only system known to contain both inner transiting super-Earths and a confirmed outer transiting gas giant companion beyond 1 au. Using long-t…