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SWIFT J0503.7-2819: a nearly synchronous intermediate polar below the period gap?
Pandey, J. C.; Scaringi, Simone; Joshi, Arti +2 more
Based on the X-ray observations from XMM-Newton and Swift, and optical observations from Transiting Exoplanet Survey Satellite (TESS) and AAVSO, we present temporal and spectral properties of probable intermediate polar SWIFT J0503.7-2819. The X-ray light curve shows two distinctive features, where possibly the second pole seems to be active durin…
Searching for nascent planetary nebulae: OHPNe candidates in the SPLASH survey
Miranda, Luis F.; de Gregorio-Monsalvo, Itziar; Imai, Hiroshi +7 more
The evolution of asymptotic giant branch stars from the spherical symmetry into the diverse shapes of planetary nebulae (PNe) is a topic of intensive research. Young PNe provide a unique opportunity to characterize the onset of this transitional phase. In particular, OH maser-emitting PNe (OHPNe) are considered nascent PNe. In fact, only six OHPNe…
QU Vul: An integral field spectroscopy case study of a nova shell
Guerrero, M. A.; Toalá, J. A.; Santamaría, E. +2 more
We present GTC MEGARA high-dispersion integral field spectroscopic observations of the nova remnant QU Vul, which provide a comprehensive 3D view of this nova shell. The tomographic analysis of the H α emission reveals a complex physical structure characterized by an inhomogeneous and clumpy distribution of the material within this shell. The over…
Core orientations and magnetic fields in isolated molecular clouds
Soam, Archana; Lee, Chang Won; Sharma, Ekta +2 more
Molecular clouds are sites of star formation. Magnetic fields are believed to play an important role in their dynamics and shaping morphology. We aim to study any possible correlation that might exist between the magnetic fields orientation inside the clouds and the magnetic fields at envelope scales and their connection with respect to the observ…
Dynamical orbital evolution scenarios of the wide-orbit eccentric planet HR 5183b
Blunt, Sarah; Mustill, Alexander J.; Davies, Melvyn B. +1 more
The recently discovered giant exoplanet HR5183b exists on a wide, highly eccentric orbit (a = 18 au, e = 0.84). Its host star possesses a common proper-motion companion which is likely on a bound orbit. In this paper, we explore scenarios for the excitation of the eccentricity of the planet in binary systems such as this, considering planet-planet…
On measuring the Hubble constant with X-ray reverberation mapping of active galactic nuclei
Ingram, Adam; García, Javier A.; Kara, Erin +8 more
We show that X-ray reverberation mapping can be used to measure the distance to type 1 active galactic nuclei (AGNs). This is because X-ray photons originally emitted from the 'corona' close to the black hole irradiate the accretion disc and are reemitted with a characteristic 'reflection' spectrum that includes a prominent ~6.4 keV iron emission …
Nebular abundance gradient in the Cartwheel galaxy using MUSE data
Ramos-Larios, Gerardo; Mayya, Divakara; Zaragoza-Cardiel, Javier +1 more
We here present the results from a detailed analysis of nebular abundances of commonly observed ions in the collisional ring galaxy Cartwheel using the Very Large Telescope (VLT) Multi-Unit Spectroscopic Explorer (MUSE) data set. The analysis includes 221 H II regions in the star-forming ring, in addition to 40 relatively fainter H α-emitting regi…
Forbush decreases associated with coronal mass ejections from active and non-active regions: statistical comparison
Melkumyan, A. A.; Belov, A. V.; Abunina, M. A. +4 more
In this paper, Forbush decreases (FDs) from 1997 to 2020 associated with coronal mass ejections from active and non-active regions are compared between themselves and to FDs caused by high-speed streams from coronal holes. The two types of sporadic FDs are also compared when corresponding solar wind (SW) disturbances contain, or do not contain, ma…
Lithium abundances as a tracer of asymptotic giant branch star pollution in the globular cluster NGC 6752
Lucatello, Sara; Pietrinferni, Adriano; Rain, M. J. +1 more
This paper presents a chemical abundance analysis of 217 stars in the metal-poor globular cluster NGC 6752, distributed from the turn-off to the lower red giant branch. Al and Li abundances were derived through spectral synthesis applied to spectra collected with FLAMES, in both GIRAFFE and UVES modes. The work aims to gain insight into the nature…
Orbital parameters and activity of ZZ Tau - a low-mass young binary with circumbinary disc
Safonov, B.; Belinski, A.; Emelyanov, N. +5 more
We present the results of our new observations of the young binary ZZ Tau with a circumbinary disc. The system was found to consist of two coeval (age < 2 Myr) classical T Tauri stars with the total mass 0.86 ± 0.09 M⊙, orbital period 46.8 ± 0.8 yr, semimajor axis 88.2 ± 2.1 mas, eccentricity 0.58 ± 0.02, and the orbital inclination …