Catálogo de publicaciones - revistas

<jats:title>Abstract</jats:title> <jats:p>The physical origin of fast radio bursts (FRBs) is unknown. Young magnetars born from gamma-ray bursts (GRBs) have been suggested as a possible central engine of FRBs. We test such a hypothesis by systematically searching for GRB–FRB spatial associations from 110 FRBs and 1440 GRBs. We find that one FRB event discovered by the Parkes telescope, FRB 171209, is spatially coincident with a historical long-duration GRB 110715A at <jats:italic>z</jats:italic> = 0.82. The afterglow of GRB 110715A is consistent with being powered by a millisecond magnetar. The extragalactic dispersion measure of FRB 171209 is in excess of that contributed by the intergalactic medium, which can be interpreted as being contributed by a young supernova remnant associated with the GRB. Overall, the significance of the association is (2.28–2.55)<jats:italic>σ</jats:italic>. If the association is indeed physical, our result suggests that the magnetars associated with long GRBs can be the progenitors of at least some FRBs.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>With the increasing number of large stellar survey projects, the quality and quantity of excellent tracers for studying the Milky Way are rapidly growing, one of which is the classical Cepheids. Classical Cepheids are high-precision standard candles with very low typical uncertainties (&lt;3%) available via the mid-infrared period–luminosity relation. About 3500 classical Cepheids identified from the Optical Gravitational Lensing Experiment, All-Sky Automated Survey for Supernova, Gaia, Wide-field Infrared Survey Explorer, and Zwicky Transient Facility survey data have been analyzed in this work, and their spatial distributions show a clear signature of Galactic warp. Two kinematical methods are adopted to measure the Galactic rotation curve (RC) in the Galactocentric distance range of <jats:inline-formula> <jats:tex-math> <?CDATA $4\lesssim {R}_{\mathrm{GC}}\lesssim 19\,\mathrm{kpc}$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjlab8d45ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>. Gently declining RCs are derived by both the proper motion (PM) method and three-dimensional velocity vector (3DV) method. The largest sample of classical Cepheids with the most accurate 6D phase-space coordinates available to date are modeled in the 3DV method, and the resulting RC is found to decline at the relatively smaller gradient of (−1.33 ± 0.1) <jats:inline-formula> <jats:tex-math> <?CDATA $\mathrm{km}\,{{\rm{s}}}^{-1}\,{\mathrm{kpc}}^{-1}$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjlab8d45ieqn2.gif" xlink:type="simple" /> </jats:inline-formula>. Comparing to results from the PM method, a higher rotation velocity ((232.5 ± 0.83) <jats:inline-formula> <jats:tex-math> <?CDATA $\mathrm{km}\,{{\rm{s}}}^{-1}$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjlab8d45ieqn3.gif" xlink:type="simple" /> </jats:inline-formula>) is derived at the position of the Sun in the 3DV method. The virial mass and local dark matter density are estimated from the 3DV method, which is the more reliable method, <jats:inline-formula> <jats:tex-math> <?CDATA ${M}_{\mathrm{vir}}=(0.822\pm 0.052)\times {10}^{12}\,{M}_{\odot }$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjlab8d45ieqn4.gif" xlink:type="simple" /> </jats:inline-formula> and <jats:inline-formula> <jats:tex-math> <?CDATA ${\rho }_{\mathrm{DM},\odot }=0.33\pm 0.03$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjlab8d45ieqn5.gif" xlink:type="simple" /> </jats:inline-formula> GeV, respectively.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>We analyze TESS photometry of DMPP-1 (HD 38677; TIC 66560666), a nearby F8V star hosting hot super-Earth planets and a warm Neptune. Using the Transit Least Squares algorithm and other methods we find a transit signal at <jats:inline-formula> <jats:tex-math> <?CDATA $P={3.2854}_{-0.0025}^{+0.0032}$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjlab8f2bieqn1.gif" xlink:type="simple" /> </jats:inline-formula> days with depth <jats:inline-formula> <jats:tex-math> <?CDATA ${87}_{-30}^{+25}$?> </jats:tex-math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjlab8f2bieqn2.gif" xlink:type="simple" /> </jats:inline-formula> ppm and false alarm probability 1.6%. This is shallower than hitherto published TESS discoveries. The 3.285 day signal is recovered for several, but not all, methods for detrending stellar astrophysical variability. Further observations are needed to improve the significance of the detection. If this transit were due to an Earth-like rocky planet it would have been detected in the RV data, but it is not. The TESS data cover seven individual transits, one of which is consistent with zero depth. The insolation of the putative planet is 990 <jats:italic>S</jats:italic> <jats:sub>⊕</jats:sub>, typical of fluxes experienced by the three known catastrophically disintegrating exoplanets (CDEs). The transits can be self-consistently attributed to a CDE with a mass below the RV detection threshold. We searched for transits of the known RV planets, finding null results and detection thresholds of &lt;100 ppm, which we quantify for each. The DMPP-1 planetary system was discovered as a consequence of circumstellar gas attributed to ablation of hot planets. The RV planets may have been ablated to near-pure iron cores. We place limits on the orbital inclinations of the RV planets where the expected transit depth exceeds the detection threshold. If the 3.2854 day transit detection is confirmed, e.g., with CHEOPS photometry, DMPP-1 would be a first-rate target for James Webb Space Telescope spectroscopy.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>GW Ori is a hierarchical triple system with a rare circumtriple disk. We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of 1.3 mm dust continuum and <jats:sup>12</jats:sup>CO <jats:italic>J</jats:italic> = 2 − 1 molecular gas emission of the disk. For the first time, we identify three dust rings in the GW Ori disk at ∼46, 188, and 338 au, with estimated dust mass of 74, 168, and 245 Earth masses, respectively. To our knowledge, its outermost ring is the largest dust ring ever found in protoplanetary disks. We use visibility modeling of dust continuum to show that the disk has misaligned parts, and the innermost dust ring is eccentric. The disk misalignment is also suggested by the CO kinematics. We interpret these substructures as evidence of ongoing dynamical interactions between the triple stars and the circumtriple disk.</jats:p>

<jats:title>Abstract</jats:title> <jats:p>In contrast with the fast solar wind, which originates in coronal holes, the source of the slow solar wind is still debated. Often intermittent and enriched with low first ionization potential elements—akin to what is observed in closed coronal loops—the slow wind could form in bursty events nearby helmet streamers. Slow winds also exhibit density perturbations that have been shown to be periodic and could be associated with flux ropes ejected from the tip of helmet streamers, as shown recently by the WISPR white-light imager on board Parker Solar Probe (PSP). In this work, we propose that the main mechanism controlling the release of flux ropes is a flow-modified tearing mode at the heliospheric current sheet (HCS). We use magnetohydrodynamic simulations of the solar wind and corona to reproduce realistic configurations and outflows surrounding the HCS. We find that this process is able to explain long (∼10–20 hr) and short (∼1–2 hr) timescales of density structures observed in the slow solar wind. This study also sheds new light on the structure, topology, and composition of the slow solar wind, and could be, in the near future, compared with white light and in situ PSP observations.</jats:p>