Search Publications
Evolution of the Spin, Spectrum and Superorbital Period of the Ultraluminous X-Ray Pulsar M51 ULX7
Israel, Gian Luca; Fürst, Felix; Walton, Dominic J. +6 more
M51 ULX7 is among a small group of known ultraluminous X-ray pulsars (ULXPs). The neutron star powering the source has a spin period of 2.8 s, orbits its companion star with a period of 2 days, and a superorbital period of 38 days is evident in its X-ray lightcurve. Here we present NuSTAR and XMM-Newton data on the source from 2019 obtained when t…
KMT-2021-BLG-1898: Planetary microlensing event involved with binary source stars
Han, Cheongho; Lee, Chung-Uk; Zang, Weicheng +18 more
Aims: The light curve of the microlensing event KMT-2021-BLG-1898 exhibits a short-term central anomaly with double-bump features that cannot be explained by the usual binary-lens or binary-source interpretations. With the aim of interpreting the anomaly, we analyze the lensing light curve under various sophisticated models.
Methods: We …
Discovery of a highly magnetic He-sdO star from a double-degenerate binary merger
Geier, S.; Heber, U.; Justham, S. +4 more
Helium-rich hot subdwarf stars of spectral type O (He-sdO) are considered prime candidates for stellar merger remnants. Such events should lead to the generation of strong magnetic fields. However, no magnetic He-sdO has yet been unambiguously discovered despite the high magnetic rate (20%) among white dwarf stars, the progeny of hot subdwarfs. He…
Galaxy source counts at 7.7, 10, and 15 µm with the James Webb Space Telescope
Kilerci, Ece; Hashimoto, Tetsuya; Goto, Tomotsugu +7 more
We present mid-infrared (IR) galaxy number counts based on the Early Release Observations obtained by the James Webb Space Telescope (JWST) at 7.7-, 10-, and 15-µm (F770W, F1000W, and F1500W, respectively) bands of the Mid-Infrared Instrument (MIRI). Due to the superior sensitivity of JWST, the 80-per cent completeness limits reach 0.32, 0.7…
Shining ALP dark radiation
Jaeckel, Joerg; Yin, Wen
String scenarios typically not only predict axionlike particles (ALPs) but also significant amounts of ALP dark radiation originating from the decay of the inflaton or a more general modulus. In this paper, we study the decay of such nonthermally produced relativistic (but massive) ALPs to photons. If the ALPs are sufficiently highly energetic, co…
From the Fire: A Deeper Look at the Phoenix Stream
Smith, M.; Abbott, T. M. C.; Allam, S. +64 more
We use 6 yr of data from the Dark Energy Survey to perform a detailed photometric characterization of the Phoenix stellar stream, a 15° long, thin, dynamically cold, low-metallicity stellar system in the Southern Hemisphere. We use natural splines, a nonparametric modeling technique, to simultaneously fit the stream track, width, and linear densit…
Measuring Optical Extinction toward Young Stellar Objects Using Diffuse Interstellar Bands
Hillenbrand, Lynne A.; Carvalho, Adolfo S.
Line-of-sight extinction estimates of well-studied young T Tauri and Herbig Ae/Be stars are based on many different measurements and analysis methods. This has resulted in wide scatter among the published A V values for the same star. In this work, we discuss the challenges in measuring extinction to actively accreting and especially …
Homogeneous transit timing analyses of 10 exoplanet systems
Aksaker, N.; Yılmaz, M.; Southworth, J. +19 more
We study the transit timings of 10 exoplanets in order to investigate potential transit timing variations in them. We model their available ground-based light curves, some presented here and others taken from the literature, and homogeneously measure the mid-transit times. We statistically compare our results with published values and find that th…
SU Lyn - a transient symbiotic star
Iłkiewicz, Krystian; Mikołajewska, Joanna; Scaringi, Simone +3 more
SU Lyn is a binary system composed of a white dwarf and a red giant star. Although it is known to be bright and variable at X-ray wavelengths, the optical counterpart of the source appeared as a single red giant without prominent emission lines. Because of the lack of optical features typical for interacting systems, the system was classified as a…
Differential attenuation in star-forming galaxies at 0.3 ≲ z ≲ 1.5 in the SHARDS/CANDELS field
Rodighiero, G.; Feltre, A.; Franceschini, A. +21 more
We use a sample of 706 galaxies, selected as [O II]λ3727 ([O II]) emitters in the Survey for High-z Absorption Red and Dead Sources (SHARDS) on the CANDELS/GOODS-N field, to study the differential attenuation of the nebular emission with respect to the stellar continuum. The sample includes only galaxies with a counterpart in the infrared and log<…