Search Publications
A case study of oversight and neglect in the handling of massive data
Pera, M. S.; Vázquez, R. A.; Giorgi, E. E. +2 more
We present and discuss data coming from the Gaia Data Release 3 mission up to $G = 21$ mag in two stellar fields covering about 5 square degrees in the area of the open cluster NGC 2659 in the region of Vela. In combination with the pyUPMASK and ASteCA analysis packages, Gaia data provide membership probabilities, structure and fundamental paramet…
Near-UV and Optical Spectroscopic Investigation of Late-type Stars from the MIRA/Oliver Observing Station
Karmakar, Subhajeet; Pandey, Jeewan Chandra; Shedge, Riddhi +4 more
Late-type stars are the most abundant in the galactic stellar population. These stars, with the similar internal structure to the Sun, are expected to have solar-like atmospheres. Investigating the stellar parameters and chemical abundances on late-type stars is essential to provide valuable constraints about stellar age, chemical evolution, and a…
Phase-dependent Spectral Shape Changes in the Ultraluminous X-Ray Pulsar NGC 5907 ULX1
Yamaguchi, Hiroya; Kobayashi, Shogo B.; Miura, Daiki
The discovery of coherent pulsations from several ultraluminous X-ray pulsars (ULXPs) has provided direct evidence of a supercritical accretion flow. However, the geometrical structure of such an accretion flow onto the central neutron star remains poorly understood. NGC 5907 ULX1 is one of the most luminous ULXPs, with a luminosity exceeding 10
Absolute Dimensions of the Interferometric Binary HD 174881: A Test of Stellar Evolution Models for Evolved Stars
Torres, Guillermo; Monnier, John D.; van Belle, Gerard T. +1 more
We report high-resolution spectroscopic monitoring and long-baseline interferometric observations with the Palomar Testbed Interferometer (PTI) of the 215 day binary system HD 174881 (K1 II-III), composed of two giant stars. The system is spatially resolved with the PTI, as well as in archival measurements with the CHARA Array. Our analysis of the…
Dual Sources of S2 Observed in Comet 67P: Insights from Comparing ROSINA Measurements and Laboratory Simulations
Choukroun, Mathieu; Hodyss, Robert; Mahjoub, Ahmed +2 more
Hydrogen sulfide (H2S) is the fifth most abundant molecule observed in the coma of comet 67P/Churyumov–Gerasimenko (67P). Prior to its incorporation into cometary materials, H2S likely underwent ultraviolet (UV) radiation exposure, which is thought to initiate a complex sulfur chemistry. We present an investigation into the U…
ATOMS: ALMA three-millimetre observations of massive star-forming regions-XVII. High-mass star-formation through a large-scale collapse in IRAS 15394-5358
Sanhueza, Patricio; Tej, Anandmayee; Hwang, Jihye +23 more
Hub-filament systems are considered as natural sites for high-mass star formation. Kinematic analysis of the surroundings of hub-filaments is essential to better understand high-mass star formation within such systems. In this work, we present a detailed study of the massive Galactic protocluster IRAS 15394
ObsMap: Preparing observing maps with the best comparison stars for photometry
Esmer, E. M.; Baştürk, Ö.; Yalçınkaya, S.
We present ObsMap, a Python framework that allows for the interactive creation of various alternative observation maps to maximize the potential of each observing night. The code requires the user to input the star's name or equatorial coordinates, the passband of observation, field of view (FoV), and desired count level together with the minimum …
The Magnetic Field in Quiescent Star-forming Filament G16.96+0.27
Pattle, Kate; Sanhueza, Patricio; Kwon, Woojin +20 more
We present 850 µm thermal dust polarization observations with a resolution of 14.″4 (∼0.13 pc) toward an infrared dark cloud G16.96+0.27 using James Clerk Maxwell Telescope/POL-2. The average magnetic field orientation, which roughly agrees with the larger-scale magnetic field orientation traced by the Planck 353 GHz data, is approximately p…
A Model of the C IV λ λ1548, 1550 Doublet Line in T Tauri Stars
France, Kevin; Calvet, Nuria; Espaillat, Catherine C. +7 more
The C IV doublet in the UV has long been associated with accretion in T Tauri stars. However, it is still unclear where and how the lines are formed. Here, we present a new C IV line model based on the currently available accretion shock and accretion flow models. We assume axisymmetric, dipolar accretion flows with different energy fluxes and cal…
Unveiling the role of magnetic fields in a filament accreting onto a young protocluster
Caselli, Paola; Redaelli, Elena; Duarte-Cabral, Ana +4 more
Context. To develop a more comprehensive picture of star formation, it is essential to understand the physical relationship between dense cores and the filaments embedding them. There is evidence that magnetic fields play a crucial role in this context.
Aims: We aim to understand how magnetic fields influence the properties and kinematics of …