Search Publications
The TESS-Keck Survey. XIII. An Eccentric Hot Neptune with a Similar-mass Outer Companion around TOI-1272
Batalha, Natalie M.; Bieryla, Allyson; Latham, David W. +58 more
We report the discovery of an eccentric hot Neptune and a non-transiting outer planet around TOI-1272. We identified the eccentricity of the inner planet, with an orbital period of 3.3 days and R p,b = 4.1 ± 0.2 R ⊕, based on a mismatch between the observed transit duration and the expected duration for a circular orbit. Usin…
Modeling the complete set of Cassini's UVIS occultation observations of Enceladus' plume
Esposito, Larry W.; Portyankina, Ganna; Aye, Klaus-Michael +2 more
The Cassini Ultraviolet Imaging Spectrograph (UVIS) observed a plume of water vapor spewing out from the south polar regions of Enceladus via occultations 7 times during the Cassini mission. Five of them yielded spatially resolved data that allowed fits to a set of individually modeled jets. We created a direct simulation Monte Carlo (DSMC) model …
Using Single-view Observations of Cometary Plasma Tails to Infer Solar Wind Speed
Wang, Yuming; Li, Xiaolei; Cheng, Long
A comet plasma tail is a product of the interaction between the solar wind and the comet's coma, and has long been studied as a natural probe of the solar wind condition. We previously developed a method to derive the solar wind speed from dual-view observations of comet plasma tails. Here we improve the method to use single-view observations by a…
Deblurring galaxy images with Tikhonov regularization on magnitude domain
Takeuchi, Tsutomu T.; Murata, Kazumi
We propose a regularization-based deblurring method that works efficiently for galaxy images. The spatial resolution of a ground-based telescope is generally limited by seeing conditions and is much worse than space-based telescopes. This circumstance has generated considerable research interest in the restoration of spatial resolution. Since imag…
What is the origin of the stacked radio emission in radio-undetected quasars?. Insights from a radio-infrared image stacking analysis
Retana-Montenegro, E.
Radio emission in the brightest radio quasars can be attributed to processes inherent to active galactic nuclei (AGN) powered by super massive black holes (SMBHs), while the physical origins of the radio fluxes in quasars without radio detections have not been established with full certainly. Deep radio surveys carried out with the Low Frequency A…
Unravelling the nature of the dual AGN in the galaxy pair system IRAS 05589+2828 and 2MASX J06021107 + 2828382
Jiménez-Bailón, E.; Marziani, P.; Chavushyan, V. H. +10 more
We have studied the nuclear region of the previously detected dual AGN system in the galaxy pair IRAS 05589 + 2828 and 2MASX J06021107 + 2828382, through new optical spectroscopy observations, along with radio and X-ray archival data. Our multiwavelength data strongly suggest that the Sy1 IRAS 05589+2828 (z = 0.0330 ± 0.0002) conforms to a dual AG…
Spiral density-wave structure parameters in the solar neighbourhood derived from longitudinal velocities of Gaia EDR3 OB stars: 3D approach
Mróz, Przemek; Gedalin, Michael; Jiang, Ing-Guey +2 more
Distances and transverse along the Galactic longitude velocities vl of 2640 Gaia EDR3 O-B2 stars of Xu et al. within 2.5 kpc from the Sun and 250 pc from the Galactic plane with relative distance and velocity accuracies of <10 and <50 per cent are selected. Under the assumption of spiral density waves, both Galactic differential r…
Study of the Mass-loss Rate from the Sun
Gopalswamy, Nat; Yashiro, Seiji; Michalek, Grzegorz
We investigate the temporal evolution of the yearly total mass-loss rate (YTMLR) from the Sun through coronal mass ejections (CMEs) over solar cycles 23 and 24. The mass determination of CMEs can be subject to significant uncertainty. To minimize this problem, we have used extensive statistical analysis. For this purpose, we employed data included…
Dynamics of Explosive Events Observed by the Interface Region Imaging Spectrograph
Tavabi, E.; Zeighami, S.; Heydari, M.
In this research, we investigate Explosive Events (EEs) in the off-limb solar atmosphere, with simultaneous observations from the Si IV, Mg II k, and slit-jaw images (SJI) of the Interface Region Imaging Spectrograph (IRIS), on 17 August 2014, and 19 February. IRIS data can be investigated to observe the motion of matter, fluctuations, energy abso…
Ultraviolet Observations of Comet 96/P Machholz at Perihelion
Raymond, J. C.; Bemporad, A.; Giordano, S. +2 more
Ultraviolet spectra of Comet 96/P Machholz were obtained during its 2002 perihelion with the UltraViolet Coronagraph Spectrometer instrument on board the SOHO satellite. Emission from H I, C II, C III, and O I is detected near the nucleus. The outgassing rate is in line with the value extrapolated from rates at larger distances from the Sun, and a…