Search Publications

Temperature stability in the sub-milliHertz band with LISA Pathfinder
DOI: 10.1093/mnras/stz1017 Bibcode: 2019MNRAS.486.3368A

Mendes, L.; Russano, G.; Lloro, I. +79 more

LISA Pathfinder (LPF) was a technology pioneering mission designed to test key technologies required for gravitational wave detection in space. In the low frequency regime (milliHertz and below), where space-based gravitational wave observatories will operate, temperature fluctuations play a crucial role since they can couple into the interferomet…

2019 Monthly Notices of the Royal Astronomical Society
LISAPathfinder 25
CG X-1: An Eclipsing Wolf-Rayet ULX in the Circinus Galaxy
DOI: 10.3847/1538-4357/ab16e7 Bibcode: 2019ApJ...877...57Q

Soria, Roberto; Liu, Jifeng; Walton, Dominic J. +7 more

We investigated the time-variability and spectral properties of the eclipsing X-ray source Circinus Galaxy X-1 (GG X-1), using Chandra, XMM-Newton and ROSAT. We phase-connected the light curves observed over 20 yr, and we obtained a best-fitting period P = (25,970.0 ± 0.1) s ≈ 7.2 hr, and a period derivative \dot{P}/P=(10.2+/- 4.6)× {10}-7

2019 The Astrophysical Journal
XMM-Newton eHST 25
Multi-wavelength variability of the young solar analog ι Horologii. X-ray cycle, star spots, flares, and UV emission
DOI: 10.1051/0004-6361/201935703 Bibcode: 2019A&A...631A..45S

Sanz-Forcada, J.; Stelzer, B.; Raetz, S. +2 more

Context. Chromospheric activity cycles are common in late-type stars; however, only a handful of coronal activity cycles have been discovered. ι Hor is the most active and youngest star with known coronal cycles. It is also a young solar analog, and we are likely facing the earliest cycles in the evolution of solar-like stars, at an age ( 600 Myr)…

2019 Astronomy and Astrophysics
XMM-Newton eHST 25
Using ALMA to resolve the nature of the early star-forming large-scale structure PLCK G073.4-57.5
DOI: 10.1051/0004-6361/201833252 Bibcode: 2019A&A...625A..96K

Frye, Brenda; Hill, Ryley; Béthermin, Matthieu +10 more

Galaxy clusters at high redshift are key targets for understanding matter assembly in the early Universe, yet they are challenging to locate. A sample of more than 2000 high-z candidate structures has been found using Planck's all-sky submillimetre maps, and a sub-set of 234 have been followed up with Herschel-SPIRE, which showed that the emission…

2019 Astronomy and Astrophysics
Herschel 25
Single-spacecraft Identification of Flux Tubes and Current Sheets in the Solar Wind
DOI: 10.3847/2041-8213/ab32d9 Bibcode: 2019ApJ...881L..11P

Servidio, Sergio; Pecora, Francesco; Greco, Antonella +3 more

A novel technique is presented for describing and visualizing the local topology of the magnetic field using single-spacecraft data in the solar wind. The approach merges two established techniques: the Grad-Shafranov (GS) reconstruction method, which provides a plausible regional two-dimensional magnetic field surrounding the spacecraft trajector…

2019 The Astrophysical Journal
Cluster 25
Asteroseismology of Massive Stars with the TESS Mission: The Runaway β Cep Pulsator PHL 346 = HN Aqr
DOI: 10.3847/2041-8213/ab095f Bibcode: 2019ApJ...873L...4H

Gazeas, Kosmas; Bowman, Dominic M.; Ricker, George R. +21 more

We report an analysis of the first known β Cep pulsator observed by the Transiting Exoplanet Survey Satellite (TESS) mission, the runaway star PHL 346 = HN Aqr. The star, previously known as a singly periodic pulsator, has at least 34 oscillation modes excited, 12 of those in the g-mode domain and 22 p modes. Analysis of archival data implies that…

2019 The Astrophysical Journal
Gaia IUE 25
Multi-point galactic cosmic ray measurements between 1 and 4.5 AU over a full solar cycle
DOI: 10.5194/angeo-37-903-2019 Bibcode: 2019AnGeo..37..903H

Guo, Jingnan; Heber, Bernd; Kuulkers, Erik +6 more

The radiation data collected by the Standard Radiation Environment Monitor (SREM) aboard ESA missions INTEGRAL (INTErnational Gamma-Ray Astrophysics Laboratory), Rosetta, Herschel, Planck and Proba-1, and by the high-energy neutron detector (HEND) instrument aboard Mars Odyssey, are analysed with an emphasis on characterising galactic cosmic rays …

2019 Annales Geophysicae
INTEGRAL Rosetta 25
Wide binary companions to massive stars and their use in constraining natal kicks
DOI: 10.1093/mnras/stz1024 Bibcode: 2019MNRAS.486.4098I

Igoshev, Andrei P.; Perets, Hagai B.

The origin of ultrawide massive binaries (orbital separations 103-2 × 105 au) and their properties are neither well characterized nor understood. Here we use the second Gaia data release to search for wide astrometric companions to Galactic O-B5 stars which share similar parallax and proper motion with the primaries. Using th…

2019 Monthly Notices of the Royal Astronomical Society
Gaia 25
Calibration of the mixing-length theory for structures of helium-dominated atmosphere white dwarfs
DOI: 10.1093/mnras/stz2656 Bibcode: 2019MNRAS.490.1010C

Ludwig, H. -G.; Fontaine, G.; Tremblay, P. -E. +5 more

We perform a calibration of the mixing-length parameter at the bottom boundary of the convection zone for helium-dominated atmospheres of white dwarfs. This calibration is based on a grid of 3D DB (pure-helium) and DBA (helium-dominated with traces of hydrogen) model atmospheres computed with the CO5BOLD radiation-hydrodynamics code, and a grid of…

2019 Monthly Notices of the Royal Astronomical Society
Gaia 25
Deep ATCA and VLA Radio Observations of Short-GRB Host Galaxies. Constraints on Star Formation Rates, Afterglow Flux, and Kilonova Radio Flares
DOI: 10.3847/1538-4357/ab528a Bibcode: 2019ApJ...887..206K

Palazzi, E.; Greiner, J.; Hunt, L. K. +6 more

We report the results of an extensive radio-continuum observing campaign of host galaxies of short gamma-ray bursts (GRBs). The goal of this survey was to search for optically obscured star formation, possibly indicative of a population of young short-GRB progenitors. Our sample comprises the hosts and host-galaxy candidates of 16 short-GRBs from …

2019 The Astrophysical Journal
eHST 25