Search Publications
Tracing the evolving X-ray reverberation lags within an individual AGN light curve
Chainakun, P.; Young, A. J.; Nakhonthong, N. +1 more
We present the Granger causality (GC) test for the X-ray reverberation analysis of Active Galactic Nuclei (AGNs). If the light curves in the continuum-dominated band help predict (Granger cause) those dominated by reflection, the Granger lags that associate to the intrinsic reverberation lags can be inferred. We focus on six AGNs observed by XMM-N…
MUSE observations of the optical nebula surrounding the central compact object in the Vela Junior supernova remnant
Safi-Harb, Samar; Ho, Wynn C. G.; Ruiter, Ashley J. +6 more
Central compact objects (CCOs), neutron stars found near the centre of some supernova remnants (SNRs), have been almost exclusively studied in X-rays and are thought to lack the wind nebulae typically seen around young, rotation-powered pulsars. We present the first, spatially resolved, morphological and spectroscopic study of the optical nebula o…
LISA and LISA-like mission test-mass charging for gamma-ray burst detection
Grimani, Catia; Villani, Mattia; Fabi, Michele +1 more
Cubic gold-platinum test-masses (TMs) play the role of free-falling geodesic reference and interferometer end mirrors of the future Laser Interferometer Space Antenna (LISA) observatory for low-frequency gravitational wave detection in space. A similar arrangement has been proposed for the Chinese missions Taiji and TianQin and for the LISA follow…
Magneto-inertial range dominated by magnetic helicity in space plasmas
Bershadskii, Alexander
Magneto-inertial range dominated by magnetic helicity has been studied using results of the numerical simulations, laboratory measurements, solar, solar wind, and the Earth's and planets' magnetosphere observations (spacecraft measurements). The spectral data have been compared with the theoretical results based on the distributed chaos notion in …
The Changes in Multiscale Solar Wind Fluctuations on the Path from the Sun to Earth
Volodin, Igor D.; Riazantseva, Maria O.; Rakhmanova, Liudmila S. +2 more
This paper is devoted to the analysis of fluctuations in the solar wind plasma and interplanetary magnetic field parameters observed by Solar Orbiter and WIND spacecraft at different scales ranging from ~103 to 107 km. We consider two long data intervals where the distances between the spacecraft are 0.1 and 0.5 AU, respectiv…
JWST Spectrophotometry of the Small Satellites of Uranus and Neptune
Brown, Michael E.; Belyakov, Matthew; Wong, Ian +2 more
We use 1.4–4.6 µm multiband photometry of the small inner Uranian and Neptunian satellites obtained with the James Webb Space Telescope's near-infrared imager NIRCam to characterize their surface compositions. We find that the satellites of the ice giants have, to first order, similar compositions to one another, with a 3.0 µm absorpti…
Stars, bow shocks, and gamma-ray sources
Benaglia, P.
Here I present a somewhat personal review of the results of my research carried out in the last couple of decades, mostly focused in the fields of stellar astrophysics, the interstellar medium, and the high energy sources. They have been obtained mainly from dedicated interferometric observations in the radio band at low frequencies of the electro…
High-resolution imaging of the evolving bipolar outflows in symbiotic novae: The case of the RS Ophiuchi 2021 nova outburst
Munari, U.; Giroletti, M.; Williams, D. R. A. +6 more
Context. The recurrent and symbiotic nova RS Ophiuchi (RS Oph) underwent a new outburst phase during August 2021, about 15 years after the last event that occurred in 2006. This outburst represents the first nova event ever detected at very high energies (VHE, E > 100 GeV), and a whole set of coordinated multiwavelength observations were trigge…
Confirmation of the presence of a CRSF in the NICER spectrum of X 1822-371
Sanna, A.; Di Salvo, T.; Burderi, L. +6 more
Aims: X 1822-371 is an eclipsing binary system with a period close to 5.57 h and an orbital period derivative Ṗorb of 1.42(3) × 10−10 s s−1. The extremely high value of its Ṗorb is compatible with a super-Eddington mass transfer rate from the companion star and, consequently, an intrinsic luminosity…
Coronal and chromospheric activity of Teegarden's star
Schmitt, J. H. M. M.; Czesla, S.; Reiners, A. +11 more
Teegarden's star is a late-type M-dwarf planet host, typically showing only rather low levels of activity. In this paper we present an extensive characterisation of this activity at photospheric, chromospheric, and coronal levels. We specifically investigated TESS observations of Teegarden's star, which showed two very large flares with an estimat…