Search Publications
The Physical Origins of the Identified and Still Missing Components of the Warm-Hot Intergalactic Medium: Insights from Deep Surveys in the Field of Blazar 1ES1553+113
Johnson, Sean D.; Drout, Maria R.; Chen, Hsiao-Wen +11 more
The relationship between galaxies and the state/chemical enrichment of the warm-hot intergalactic medium (WHIM) expected to dominate the baryon budget at low-z provides sensitive constraints on structure formation and galaxy evolution models. We present a deep redshift survey in the field of 1ES1553+113, a blazar with a unique combination of ultra…
Late-time observations of the extraordinary Type II supernova iPTF14hls
Cenko, S. B.; Sollerman, J.; Gal-Yam, A. +22 more
Aims: We study iPTF14hls, a luminous and extraordinary long-lived Type II supernova, which lately has attracted much attention and disparate interpretation.
Methods: We have presented new optical photometry that extends the light curves up to more than three years past discovery. We also obtained optical spectroscopy over this period, an…
The Physics of the Accelerating Universe Camera
Carretero, Jorge; Castander, Francisco J.; Eriksen, Martin +30 more
The Physics of the Accelerating Universe (PAU) Survey goal is to obtain photometric redshifts (photo-z) and spectral energy distributions (SEDs) of astronomical objects with a resolution roughly one order of magnitude better than current broadband (BB) photometric surveys. To accomplish this, a new large field-of-view (FoV) camera (PAUCam) has bee…
Detection of a giant flare displaying quasi-periodic pulsations from a pre-main-sequence M star by the Next Generation Transit Survey
Jackman, James A. G.; Wheatley, Peter J.; Raddi, Roberto +18 more
We present the detection of an energetic flare on the pre-main-sequence M3 star NGTS J121939.5-355557, which we estimate to be only 2 Myr old. The flare had an energy of 3.2± ^{0.4}_{0.3}× 10^{36} erg and a fractional amplitude of 7.2 ± 0.8, making it one of the most energetic flares seen on an M star. The star is also X-ray active, in the saturat…
Background for a gamma-ray satellite on a low-Earth orbit
Hernanz, M.; Cumani, P.; Kiener, J. +2 more
The different background components in a low-Earth orbit have been modeled in the 10 keV to 100 GeV energy range. The model is based on data from previous instruments and it considers both primary and secondary particles, charged particles, neutrons and photons. The necessary corrections to consider the geomagnetic cutoff are applied to calculate …
A catalogue of Galactic supernova remnants in the far-infrared: revealing ejecta dust in pulsar wind nebulae
De Looze, I.; Rho, J.; Dunne, L. +7 more
We search for far-infrared counterparts of known supernova remnants (SNRs) in the Galactic plane (10° < |l| < 60°) at 70-500 µm using the Herschel Infrared Galactic Plane Survey (Hi-GAL). Of 71 sources studied, we find that 29 (41 per cent) SNRs have a clear FIR detection of dust emission associated with the SNR. Dust from 8 of these i…
Precise Ages of Field Stars from White Dwarf Companions
Tian, Haijun; Rix, Hans-Walter; Fouesneau, Morgan +2 more
Observational tests of stellar and Galactic chemical evolution call for the joint knowledge of a star’s physical parameters, detailed element abundances, and precise age. For cool main-sequence (MS) stars the abundances of many elements can be measured from spectroscopy, but ages are very hard to determine. The situation is different if the MS sta…
The Nature of Ionized Gas in the Milky Way Galactic Fountain
Zheng, Y.; Prochaska, J. X.; Deason, A. J. +6 more
We address the spatial scale, ionization structure, mass, and metal content of gas at the Milky Way disk-halo interface detected as absorption in the foreground of seven closely spaced, high-latitude halo blue horizontal branch stars with heights z = 3-14 kpc. We detect transitions that trace multiple ionization states (e.g., Ca II, Fe II, Si IV, …
Isotopic ratios of Saturn's rings and satellites: Implications for the origin of water and Phoebe
Clark, Roger N.; Brown, Robert H.; Cruikshank, Dale P. +1 more
Isotopic ratios have long been used to learn about physical processes acting over a wide range of geological environments, and in constraining the origin and/or evolution of planetary bodies. We report the spectroscopic detection of deuterium in Saturn's rings and satellites, and use these measurements to determine the (D/H) ratios in their near-s…
Photospheric magnetic structure of coronal holes
Temmer, Manuela; Veronig, Astrid; Hofmeister, Stefan J. +2 more
In this study, we investigate in detail the photospheric magnetic structure of 98 coronal holes using line-of-sight magnetograms of SDO/HMI, and for a subset of 42 coronal holes using HINODE/SOT G-band filtergrams. We divided the magnetic field maps into magnetic elements and quiet coronal hole regions by applying a threshold at ±25 G. We find tha…