Search Publications
A radical transition in the post-main-sequence system U Equulei
Menten, Karl M.; Szczerba, Ryszard; Iłkiewicz, Krystian +6 more
Context. U Equ is an unusual maser-hosting infrared source discovered in the 1990s. It was tentatively classified as a post-asymptotic giant branch (post-AGB) star with a unique optical spectrum displaying rare emission and absorption features from molecular gas at a temperature of about 500 K. In 2022, we serendipitously discovered that its optic…
HYPERION. Shedding light on the first luminous quasars: A correlation between UV disc winds and X-ray continuum
Maiolino, R.; Fiore, F.; Done, C. +41 more
One of the main open questions in the field of luminous (Lbol > 1047 erg s‑1) quasars (QSOs) at z ≳ 6 is the rapid formation (< 1 Gyr) of their supermassive black holes (SMBHs). For this work we analysed the relation between the X-ray properties and other properties describing the physics and growth of both t…
Indications of magnetic accretion in Swift J0826.2‑7033
Mukai, Koji; Falanga, Maurizio; Masetti, Nicola +3 more
We present our findings from the first long X-ray observation of the hard X-ray source Swift J0826.2‑7033 with XMM-Newton, which has shown characteristics of magnetic accretion. The system appears to have a long orbital period (∼7.8 h) accompanied by short timescale variabilities, which we tentatively interpret as the spin and beat periods of an i…
Mapping thermal emission in the synchrotron-dominated supernova remnants G330.2+1.0, 3C58, and RX J1713.7-3946
Mori, K.; Acero, F.; Williams, B. J. +1 more
Aims: Since the discovery of synchrotron X-ray emission from the shell of the supernova remnant (SNR) SN 1006, multiple observations from Chandra and XMM-Newton have shown that many young SNRs produce synchrotron emission in X-rays. Among those, a few peculiar SNRs have their X-ray emission largely dominated by synchrotron radiation, showing …
Gas flows in the central region of the Seyfert galaxy NGC 4593 with MUSE
Knapen, J. H.; Comerón, S.; Pereira-Santaella, M. +4 more
Context. Understanding how gas flows into galactic centres, fuels the active galactic nucleus (AGN), and is in turn expelled back through feedback processes is of great importance to appreciate the role AGN play in the growth and evolution of galaxies. Aims. We use Multi Unit Spectroscopic Explorer-adaptive optics (MUSE-AO) optical spectra of the …
Hubble Space Telescope proper motions of Large Magellanic Cloud star clusters: I. Catalogues and results for NGC 1850
Martocchia, S.; Cabrera-Ziri, I.; Bastian, N. +11 more
We present proper motion (PM) measurements for a sample of 23 massive star clusters within the Large Magellanic Cloud using multi-epoch data from the Hubble Space Telescope (HST). We combined archival data from the ACS/WFC and WFC3/UVIS instruments with observations from a dedicated HST programme, resulting in time baselines between 4.7 and 18.2 y…
The Lockman-SpReSO project. Main properties of infrared-selected star-forming galaxies
Krongold, Yair; Sánchez-Portal, Miguel; Bongiovanni, Ángel +18 more
Aims: In this work, we carry out a comprehensive study using galaxy data from the Lockman Spectroscopic Redshift Survey using Osiris (Lockman-SpReSO) project, a far-infrared (FIR) selected sample of galaxies observed using optical spectroscopy. We analyse a sub-sample of star-forming galaxies (SFGs) with secure spectroscopic redshifts, mostly…
A comprehensive study of five candidate δ Scuti-type pulsators in detached eclipsing binaries
Hełminiak, K. G.; Konacki, M.; Moharana, A. +4 more
Context. Pulsating stars in eclipsing binaries (EBs) provide an excellent opportunity to obtain precise, model-independent stellar parameters for studying these oscillations in detail. One of the most common classes of pulsators found in such EBs exhibits δ Scuti-type oscillations. Characterising these pulsators using the precise stellar parameter…
Rotation in stellar evolution: Probing the influence on population synthesis in high-redshift galaxies
Sun, Weijia
Stellar population synthesis (SPS) is essential for understanding galaxy formation and evolution. However, the recent discovery of rotation-driven phenomena in star clusters warrants a review of uncertainties in SPS models caused by overlooked factors, including stellar rotation. In this study, we investigated the impact of rotation on SPS specifi…
Two stellar populations with different metallicities in the low-mass globular cluster Gran 5
Chung, Chul; Lee, Young-Wook; Koch-Hansen, Andreas J. +3 more
Context. With the increasing number of discoveries of globular clusters in the inner Milky Way, the need for spectroscopic confirmation and further investigation of their stellar populations and chemodynamical properties has become crucial. Aims. Gran 5 is a newly reported low-mass globular cluster located close to the Galactic center, and it is t…