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Rotation of hot normal, peculiar and Be stars from space photometry
Balona, L. A.
The periods of 34 376 main-sequence stars hotter than 6000 K are derived from Kepler, K2, and TESS light curves. From the effective temperatures and GAIA DR3 luminosities, the radii, and hence the equatorial rotational velocities, can be estimated. Comparison with the projected rotational velocities shows that the photometric periods are indisting…
The frequency and mass-ratio distribution of binaries in clusters - I. Description of the method and application to M67
Albrow, Michael D.; Ulusele, Isaac H.
We present a new method for probabilistic generative modelling of stellar colour-magnitude diagrams (CMDs) to infer the frequency of binary stars and their mass-ratio distribution. The method invokes a mixture model to account for overlapping populations of single stars, binaries, and outliers in the CMD. We apply the model to Gaia observations of…
Spectroscopic confirmation of a gravitationally lensed Lyman-break galaxy at z[C II] = 6.827 using NOEMA
Schaerer, D.; Zitrin, A.; van der Werf, P. +8 more
We present the spectroscopic confirmation of the brightest known gravitationally lensed Lyman-break galaxy in the Epoch of Reionization (EoR), A1703-zD1, through the detection of [C II] 158 $\mu$m at a redshift of z = 6.8269 ± 0.0004. This source was selected behind the strong lensing cluster Abell 1703, with an intrinsic luminosity and a very blu…
Multiwavelength campaign on the Super-Eddington NLS1 RX J0134.2-4258 - I. Peculiar X-ray spectra and variability
Done, Chris; Ward, Martin; Jin, Chichuan +3 more
We have conducted a new long-term multiwavelength campaign on one of the most super-Eddington narrow-line Seyfert 1s (NLS1s) known, namely RX J0134.2-4258. In this first paper, we report deep simultaneous X-ray observations performed by XMM-Newton and NuSTAR on 2019 December 19, during which RX J0134.2-4258 was fortuitously at one of its lowest X-…
Characteristics of chromospheric oscillation periods in magnetic bright points
Tavabi, Ehsan; Sadeghi, Rayhane
In this investigation, oscillation periods in Mg II k-line intensity, brightness temperature, and Doppler velocity obtained above magnetic bright points (MBPs) are investigated. For this purpose, data from the Interface Region Imaging Spectrometer (IRIS) observing the higher chromosphere and transition region (TR) were analysed, together with imag…
NGC 3147: a prototypical low-luminosity active galactic nucleus with double-peaked optical and ultraviolet lines
Laor, Ari; Bianchi, Stefano; Chiaberge, Marco +3 more
A previous narrow-slit (0.1 arcsec) Hubble Space Telescope observation unveiled a broad relativistic Hα profile in NGC 3147, a low-luminosity (Lbol ~ 1042 erg s-1), low-Eddington ratio (Lbol/LEdd ~ 10-4) active galactic nucleus (AGN), formerly believed to be a candidate true type 2 …
The nature of the radio source detected towards the exoplanet system 1RXS1609.1-210524
Narang, Mayank
Several studies have been carried out to detect radio emissions from known exoplanets. Some of these studies have resulted in tentative detections of radio sources near the position of known exoplanets. One such planet/brown dwarf around which a radio source was detected is 1RXS1609.1-210524 (hereafter 1RX) b. A radio source near 1RX was detected …
Implications from secondary emission from neutral impact on Cassini plasma and dust measurements
Edberg, N. J. T.; Vigren, E.; Eriksson, A. I. +4 more
We investigate the role of secondary electron and ion emission from impact of gas molecules on the Cassini Langmuir probe (RPWS-LP or LP) measurements in the ionosphere of Saturn. We add a model of the emission currents, based on laboratory measurements and data from comet 1P/Halley, to the equations used to derive plasma parameters from LP bias v…
On the peculiar long-term orbital evolution of the eclipsing accreting millisecond X-ray pulsar SWIFT J1749.4 - 2807
Altamirano, D.; Albayati, A. C.; Sanna, A. +16 more
We present the pulsar timing analysis of the accreting millisecond X-ray pulsar SWIFT J1749.4 - 2807 monitored by NICER and XMM-Newton during its latest outburst after almost 11 yr of quiescence. From the coherent timing analysis of the pulse profiles, we updated the orbital ephemerides of the system. Large phase jumps of the fundamental frequency…
SIRIUS Project - V. Formation of off-centre ionized bubbles associated with Orion Nebula Cluster
Shimajiri, Yoshito; Hattori, Kohei; Wang, Long +4 more
Massive stars born in star clusters terminate star cluster formation by ionizing the surrounding gas. This process is considered to be prevalent in young star clusters containing massive stars. The Orion Nebula is an excellent example associated with a forming star cluster including several massive stars (the Orion Nebula Cluster, ONC) and a 2-pc-…