Astronomy & Astrophysics (A&A)
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Astronomy & Astrophysics is an international Journal that publishes papers on all aspects of astronomy and astrophysics (theoretical, observational, and instrumental) independently of the techniques used to obtain the results.
Astronomy & Astrophysics (A&A)
3w ago
Vol. 681
10. Planets and planetary systems
Formation of flattened planetesimals by gravitational collapse of rotating pebble clouds by Sebastian Lorek, Anders Johansen 2024, A&A, 681, A38 In their study, Lorek & Johansen delve into the fascinating process of how a kilometer-sized planetesimal might form from a rotating cloud of pebbles. They used a Monte Carlo method to simulate this complex process and find that when pebble clouds that rotate slowly collapse under their own gravity, they can form shapes such as flattened ellipsoids. This finding provides insights into the unique shap ..read more
Astronomy & Astrophysics (A&A)
3w ago
Vol. 682
6. Interstellar and circumstellar matter
eROSITA studies of the Carina nebula by Manami Sasaki, Jan Robrade, G.H. Martin Krause, R. Jonathan Knies, Kisetsu Tsuge, Gerd Pühlhofer, Andrew Strong 2024, A&A, 682, A172
Whatever might be wanted to study feedback processes and the symbiosis of stars and interstellar clouds can be found in the Carina nebula. This star-forming region harbors a broad range of massive stars, including the ever-popular luminous blue variable (and multiple interacting wind system) eta Carina. The region and its core clusters have been subject to continuing mu ..read more
Astronomy & Astrophysics (A&A)
1M ago
Vol. 682
6. Interstellar and circumstellar matter
eROSITA studies of the Carina nebula by Manami Sasaki, Jan Robrade, G.H. Martin Krause, R. Jonathan Knies, Kisetsu Tsuge, Gerd Pühlhofer, Andrew Strong 2024, A&A, 682, A172
Whatever might be wanted to study feedback processes and the symbiosis of stars and interstellar clouds can be found in the Carina nebula. This star-forming region harbors a broad range of massive stars, including the ever-popular luminous blue variable (and multiple interacting wind system) eta Carina. The region and its core clusters have been subject to continuing m ..read more
Astronomy & Astrophysics (A&A)
1M ago
Vol. 682
7. Stellar structure and evolution
PSR J0210+5845: Ultra-wide binary pulsar with a B6 V main sequence star companion by E. van der Wateren, C. G. Bassa, G. H. Janssen, I. V. Yanes-Rizo, J. Casares, G. Nelemans, W. B. Stappers, C. M. Tan 2024, A&A, 682, A178
A neutron star forms in the explosion of a massive star as a supernova. When the exploding star is part of a binary system, the binary usually gets disrupted. In favorable conditions (e.g., asymmetries in the supernova explosion), however, the binary system can survive, leaving a newborn neutron star orbiting a massive compani ..read more
Astronomy & Astrophysics (A&A)
1M ago
Vol. 682
12. Atomic, molecular, and nuclear data
The UMIST database for astrochemistry 2022 by T. J. Millar, C. Walsh, M. Van de Sande, A. J. Markwick 2024, A&A, 682, A109
Detailed astrochemical models are necessary for interpreting the observations of interstellar and circumstellar molecules. They depend on the values of the rate coefficients of individual chemical reactions, and these need to be continuously updated to reflect advances in experimental and theoretical estimates. In this volume, Tom Millar and collaborators present the sixth release of the UMIST Database for Astrochemistr ..read more
Astronomy & Astrophysics (A&A)
1M ago
Vol. 682
10. Planets and planetary systems
Secular change in the spin states of asteroids due to radiation and gravitation torques. New detections and updates of the YORP effect by J. Durech, D. Vokrouhlicky, P. Pravec, et al. 2024, A&A, 682, A93
The motion of near-Earth asteroids is significantly influenced by non-gravitational forces, specifically thermal torques resulting from the proximity to the Sun. These effects are known as the Yarkovsky effect for orbital dynamics and the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect when impacting the object's rotation. The latter effect i ..read more
Astronomy & Astrophysics (A&A)
2M ago
Vol. 681
2. Astrophysical processes
A MeerKAT view of the double pulsar eclipses. Geodetic precession of pulsar B and system geometry by M.E. Lower, M. Kramer, R.M. Shannon, R.P. Breton, N. Wex, et al. 2024, A&A, 681, A26 PSR J0737−3039A/B is a unique double neutron star binary system in which both neutron stars are detected as radio pulsars. In addition, the system is viewed almost edge on (90.5 deg), allowing us to study the interaction of a radio signal with the neutron star magnetosphere. A variety of general relativity tests could be carried out on this system. In this paper, Lower a ..read more
Astronomy & Astrophysics (A&A)
2M ago
Vol. 682
9. The Sun and the Heliosphere
A comparative study of two X2.2 and X9.3 solar flares observed with HARPS-N. Reconciling Sun-as-a-star spectroscopy and high-spatial resolution solar observations in the context of the solar-stellar connection by A.G.M. Pietrow, M. Cretignier, M.K. Druett, et al. 2024, A&A, 682, A46
By virtue of its proximity, the Sun has always been observed and treated differently than the more distant exemplars. However, with advances in detectors and spectrographs, it has become increasingly more feasible to obtain a similar level of information for more remote ..read more
Astronomy & Astrophysics (A&A)
2M ago
Vol. 681
6. Interstellar and circumstellar matter
S 308 and other X-ray emitting bubbles around Wolf-Rayet stars by Francesco Camilloni, Werner Becker, and Manami Sasaki 2024, A&A, 681, A122
The role of massive stars in shaping their local environment is a continuing theme in the study of galactic star formation. Including stellar feedback in galactic models through the combined effects of wind mass loss and photoionization is physically challenging and, still, hypothetical, or at best loosely based on phenomenological prescriptions. Supernovae also bespeak the need of understanding the ..read more
Astronomy & Astrophysics (A&A)
2M ago
Vol. 681
3. Cosmology (including clusters of galaxies)
ACT-DR5 Sunyaev-Zel’dovich clusters: Weak lensing mass calibration with KiDS by N. C. Robertson, C. Sifon, M. Asgari et al. 2024, A&A, 681, A87
Galaxy clusters trace the large-scale matter distribution in the Universe. It is fundamental to know precisely their number density, masses, baryon content, and evolution with redshift, to reveal the growth of structure and constrain the amplitude of matter fluctuations, the matter density, and the dark energy equation of state. They are important diagnostics of any cosmological model, and ca ..read more