Search Publications
Toward the true number of flaring giant stars in the Kepler field. Are their flaring specialities associated with their being giant stars?
Pál, A.; Günther, M. N.; Oláh, K. +4 more
Aims: We aim to give a reliable estimate of the number of flaring giant stars in the Kepler field. By analyzing the flaring activity of these stars, we explored their flare statistics and the released flare energies. The role of oscillation in suppressing magnetic activity was also investigated. We searched for flaring specialities that may b…
The HARPS search for southern extra-solar planets. XLVI. 12 super-Earths around the solar type stars HD 39194, HD 93385, HD 96700, HD 154088, and HD 189567
Alonso, R.; Bouchy, F.; Deleuil, M. +23 more
Context. We present precise radial-velocity measurements of five solar-type stars observed with the HARPS Echelle spectrograph mounted on the 3.6-m telescope in La Silla (ESO, Chile). With a time span of more than 10 yr and a fairly dense sampling, the survey is sensitive to low mass planets down to super-Earths on orbital periods up to 100 days. …
Solar surges related to UV bursts. Characterization through k-means, inversions, and density diagnostics
Guglielmino, S. L.; Sainz Dalda, A.; Nóbrega-Siverio, D.
Context. Surges are cool and dense ejections typically observed in chromospheric lines and closely related to other solar phenomena such as UV bursts or coronal jets. Even though surges have been observed for decades now, questions regarding their fundamental physical properties such as temperature and density, as well as their impact on upper lay…
Characterizing the morphology of the debris disk around the low-mass star GSC 07396-00759
Bayo, A.; Ginski, C.; Henning, Th. +17 more
Context. Debris disks have commonly been studied around intermediate-mass stars. Their intense radiation fields are believed to efficiently remove the small dust grains that are constantly replenished by collisions. For lower-mass central objects, in particular M stars, the dust removal mechanism needs to be further investigated given the much wea…
Water and methanol ice in L 1544
Alves, J.; Caselli, P.; Jiménez-Serra, I. +4 more
Context. Methanol and complex organic molecules have been found in cold starless cores, where a standard warm-up scenario would not work because of the absence of heat sources. A recent chemical model attributed the presence of methanol and large organics to the efficient chemical desorption and a class of neutral-neutral reactions that proceed fa…
The reduced proper motion selected halo: Methods and description of the catalogue
Helmi, Amina; Koppelman, Helmer H.
Context. The Gaia mission has provided the largest ever astrometric chart of the Milky Way. Using it to map the Galactic halo is helpful for disentangling its merger history.
Aims: The identification of halo stars in Gaia DR2 with reliable distance estimates requires special methods because such stars are typically farther away and scarce.
Three faint-source microlensing planets detected via the resonant-caustic channel
Han, Cheongho; Udalski, Andrzej; Lee, Chung-Uk +32 more
Aims: We conducted a project of reinvestigating the 2017-2019 microlensing data collected by high-cadence surveys with the aim of finding planets that were missed due to the deviations of planetary signals from the typical form of short-term anomalies.
Methods: The project led us to find three planets, KMT-2017-BLG-2509Lb, OGLE-2017-BLG-…
Blue extreme disk-runaway stars with Gaia EDR3
Raddi, Roberto; Irrgang, Andreas; Heber, Ulrich +1 more
Since the discovery of hypervelocity stars in 2005, it has been widely believed that only the disruption of a binary system by a supermassive black hole at the Galactic center (GC), that is, the so-called Hills mechanism, is capable of accelerating stars to beyond the Galactic escape velocity. In the meantime, however, driven by the Gaia space mis…
Atacama Cosmology Telescope measurements of a large sample of candidates from the Massive and Distant Clusters of WISE Survey. Sunyaev-Zeldovich effect confirmation of MaDCoWS candidates using ACT
Hilton, Matt; Sifón, Cristóbal; Choi, Steve K. +35 more
Context. Galaxy clusters are an important tool for cosmology, and their detection and characterization are key goals for current and future surveys. Using data from the Wide-field Infrared Survey Explorer (WISE), the Massive and Distant Clusters of WISE Survey (MaDCoWS) located 2839 significant galaxy overdensities at redshifts 0.7 ≲ z ≲ 1.5, whic…
The MUSE Hubble Ultra Deep Field Survey. XVI. The angular momentum of low-mass star-forming galaxies: A cautionary tale and insights from TNG50
Bacon, Roland; Contini, Thierry; Richard, Johan +14 more
We investigate the specific angular momentum (sAM) j(< r) profiles of intermediate redshift (0.4 < z < 1.4) star-forming galaxies (SFGs) in the relatively unexplored regime of low masses (down to M⋆ ∼ 108 M⊙) and small sizes (down to Re ∼ 1.5 kpc), and we characterize the sAM scaling relation (i…