Search Publications
The Fermi-LAT detection of magnetar-like pulsar PSR J1846-0258 at high-energy gamma-rays
Dekker, A.; Kuiper, L.; Hermsen, W.
We report the detection of the pulsed signal of the radio-quiet magnetar-like pulsar PSR J1846-0258 in the high-energy γ-ray data of the Fermi Large Area Telescope (Fermi LAT). We produced phase-coherent timing models exploiting RXTE PCA and Swift XRT monitoring data for the post- (magnetar-like) outburst period from 2007 August 28 to 2016 Septemb…
Spectroscopic and imaging observations of small-scale reconnection events
Li, Dong; Li, Leping; Ning, Zongjun
We present spectroscopic and imaging observations of small-scale reconnection events on the Sun. Using Interface Region Imaging Spectrograph (IRIS) observations, one reconnection event is first detected as IRIS jets with fast bidirectional velocities in the chromosphere and transition region, which are identified as non-Gaussian broadenings with t…
Multi-epoch analysis of the X-ray spectrum of the active galactic nucleus in NGC 5506
Ni, Qingling; Bambi, Cosimo; Guainazzi, Matteo +5 more
We present a multi-epoch X-ray spectroscopy analysis of the nearby narrow-line Seyfert I galaxy NGC 5506. For the first time, spectra taken by Chandra, XMM-Newton, Suzaku, and NuSTAR- covering the 2000-2014 time span - are analysed simultaneously, using state-of-the-art models to describe reprocessing of the primary continuum by optical thick matt…
HST imaging of four gravitationally lensed quasars
King, A. L.; Barone-Nugent, R. L.; Bate, N. F. +7 more
We present new Hubble Space Telescope WFC3 imaging of four gravitationally lensed quasars: MG 0414+0534; RXJ 0911+0551; B 1422+231; WFI J2026-4536. In three of these systems we detect wavelength-dependent microlensing, which we use to place constraints on the sizes and temperature profiles of the accretion discs in each quasar. Accretion disc radi…
A direct measure of free electron gas via the kinematic Sunyaev-Zel'dovich effect in Fourier-space analysis
Spergel, David N.; Okumura, Teppei; Sugiyama, Naonori S.
We present the measurement of the kinematic Sunyaev-Zel'dovich (kSZ) effect in Fourier space, rather than in real space. We measure the density-weighted pairwise kSZ power spectrum, the first use of this promising approach, by cross-correlating a cleaned cosmic microwave background (CMB) temperature map, which jointly uses both Planck Release 2 an…
An explanation for the gap in the Gaia HRD for M dwarfs
Gizis, John; MacDonald, James
We show that the recently discovered narrow gap in the Gaia Hertzsprung-Russell Diagram near MG = 10 can be explained by standard stellar evolution models and results from a dip in the luminosity function associated with mixing of 3He during merger of envelope and core convection zones that occurs for a narrow range of masses.
ALMA observations of a metal-rich damped Ly α absorber at z = 2.5832: evidence for strong galactic winds in a galaxy group
Fynbo, J. P. U.; Dessauges-Zavadsky, M.; Christensen, L. +7 more
We report on the results of a search for CO(3-2) emission from the galaxy counterpart of a high-metallicity Damped Ly α Absorber (DLA) at z = 2.5832 towards the quasar Q0918+1636. We do not detect CO emission from the previously identified DLA galaxy counterpart. The limit we infer on Mgas/M⋆ is in the low end of the range fo…
Red, redder, reddest: SCUBA-2 imaging of colour-selected Herschel sources
Ivison, R. J.; Clements, D. L.; Scott, D. +28 more
High-redshift, luminous, dusty star-forming galaxies (DSFGs) constrain the extremity of galaxy formation theories. The most extreme are discovered through follow-up on candidates in large area surveys. Here, we present extensive 850 µm SCUBA-2 follow-up observations of 188 red DSFG candidates from the Herschel Multitiered Extragalactic Surve…
Solar chemical composition in the hot gas of cool-core ellipticals, groups, and clusters of galaxies
Urdampilleta, I.; Simionescu, A.; Kaastra, J. S. +6 more
The hot intracluster medium (ICM) pervading galaxy clusters and groups is rich in metals, which were synthesized by billions of supernovae and have accumulated in cluster gravitational wells for several gigayears. Since the products of both Type Ia and core-collapse supernovae - expected to explode over different time-scales - are found in the ICM…
The role of spiral arms in Milky Way star formation
Moore, T. J. T.; Elia, D.; Molinari, S. +4 more
What role does Galactic structure play in star formation? We have used the Herschel Infrared Galactic Plane Survey (Hi-GAL) compact-clump catalogue to examine trends in evolutionary stage over large spatial scales in the inner Galaxy. We examine the relationship between the fraction of clumps with embedded star formation (the star-forming fraction…