Search Publications
Deep Generative Modeling of Periodic Variable Stars Using Physical Parameters
Bloom, Joshua S.; Martínez-Palomera, Jorge; Abrahams, Ellianna S.
The ability to generate physically plausible ensembles of variable sources is critical to the optimization of time domain survey cadences and the training of classification models on data sets with few to no labels. Traditional data augmentation techniques expand training sets by reenvisioning observed exemplars, seeking to simulate observations o…
The first seven months of the 2020 X-ray outburst of the magnetar SGR J1935+2154
Tiengo, A.; Mereghetti, S.; Rea, N. +10 more
The magnetar SGR J1935+2154 underwent a new active episode on 2020 April 27-28, when a forest of hundreds of X-ray bursts and a large enhancement of the persistent flux were detected. For the first time, a radio burst with properties similar to those of fast radio bursts and with a X-ray counterpart was observed from this source, showing that magn…
Ejection-accretion connection in NLS1 AGN 1H 1934-063
Cusumano, G.; Fabian, A. C.; Pinto, C. +7 more
Accretion and ejection of matter in active galactic nuclei (AGNs) are tightly connected phenomena and represent fundamental mechanisms regulating the growth of the central supermassive black hole and the evolution of the host galaxy. However, the exact physical processes involved are not yet fully understood. We present a high-resolution spectral …
Bridging the gap between Monte Carlo simulations and measurements of the LISA Pathfinder test-mass charging for LISA
Cesarini, A.; Grimani, C.; Fabi, M. +2 more
Context. Cubic gold-platinum free-falling test masses (TMs) constitute the mirrors of future LISA and LISA-like interferometers for low-frequency gravitational wave detection in space. High-energy particles of Galactic and solar origin charge the TMs and thus induce spurious electrostatic and magnetic forces that limit the sensitivity of these int…
A Mass Model for the Lensing Cluster SDSS J1004+4112: Constraints from the Third Time Delay
Kochanek, C. S.; Muñoz, J. A.; Mediavilla, E. +1 more
We have built a new model for the lens system SDSS J1004+4112 including the recently measured time delay of the fourth quasar image. This time delay has a strong influence on the inner mass distribution of the lensing cluster (ρ ∝ r -α ) allowing us to determine $\alpha ={1.18}_{-0.03(-0.18)}^{+0.02(+0.11)}$ at the 68% (95%) confidence …
Relic galaxy analogues in TNG50 simulation: the formation pathways of surviving red nuggets in a cosmological simulation
Chies-Santos, Ana L.; Ferreira, Leonardo; De Rossi, María Emilia +4 more
Relic galaxies are massive compact quiescent galaxies that formed at high-redshift and remained almost unchanged since then. In this work, we search for analogues to relic galaxies in the TNG50 cosmological simulations to understand relic formation and test the ability of TNG50 to reproduce such rare objects. Using stellar mass, age, radius, quies…
Constraints on the structure and seasonal variations of Triton's atmosphere from the 5 October 2017 stellar occultation and previous observations
Forget, F.; Strobel, D. F.; Hueso, R. +234 more
Context. A stellar occultation by Neptune's main satellite, Triton, was observed on 5 October 2017 from Europe, North Africa, and the USA. We derived 90 light curves from this event, 42 of which yielded a central flash detection.
Aims: We aimed at constraining Triton's atmospheric structure and the seasonal variations of its atmospheric press…
Tidally stripped halo stars from the Large Magellanic Cloud in the Galactic North
Peñarrubia, Jorge; Petersen, Michael S.; Jones, Ella
We examine whether the Large Magellanic Cloud (LMC) is currently losing its stellar halo to Milky Way (MW) tides. We present a live N-body model for the ongoing MW-LMC interaction that predicts a prominent stream of stars tidally stripped from the progenitor LMC. We use this model to define a strategy to search for stripped material in kinematic s…
Deep study of A399-401: Application of a wide-field facet calibration
Brunetti, G.; Shimwell, T. W.; Tasse, C. +6 more
Context. Diffuse synchrotron emission pervades numerous galaxy clusters, indicating the existence of cosmic rays and magnetic fields throughout the intra-cluster medium. The general consensus is that this emission is generated by shocks and turbulence that are activated during cluster merger events and cause a (re-)acceleration of particles to hig…
Can We Detect Coronal Mass Ejections through Asymmetries of Sun-as-a-star Extreme-ultraviolet Spectral Line Profiles?
Chen, Yajie; Gao, Yuhang; Tian, Hui +8 more
Coronal mass ejections (CMEs) are the largest-scale eruptive phenomena in the solar system. Associated with enormous plasma ejections and energy releases, CMEs have an important impact on the solar-terrestrial environment. Accurate predictions of the arrival times of CMEs at the Earth depend on precise measurements of their 3D velocities, which ca…