TY  - JOUR
A1  - Bersier, David
A1  - Fruchter, Andrew S.
A1  - Strolger, Louis-Gregory
A1  - Gorosabel, Javier
A1  - Levan, Andrew
A1  - Burud, Ingunn
A1  - Rhoads, James E.
A1  - Becker, Andrew C.
A1  - Cassan, Andrew C.
A1  - Chornock, Ryan
A1  - Covino, Stefano
A1  - De Jong, Roelof S.
A1  - Dominis, Dijana
A1  - Filippenko, Alexei V.
A1  - Hjorth, Jens
A1  - Holmberg, Johan
A1  - Malesani, Daniele
A1  - Mobasher, Bahram
A1  - Olsen, Kurt A. G.
A1  - Stefanon, Mauro
A1  - Castro Cerón, José María C.
A1  - Fynbo, Johan P. U.
A1  - Holland, Stephen T.
A1  - Kouveliotou, Chryssa
A1  - Pedersen, Hans-Georg
A1  - Tanvir, Nieal R.
A1  - Woosley, S. E.
T1  - Evidence for a supernova associated with the X-ray flash 020903
N2  - We present ground-based and Hubble Space Telescope optical observations of the X-ray flash ( XRF) 020903, covering 300 days. The afterglow showed a very rapid rise in the first day, followed by a relatively slow decay in the next few days. There was a clear bump in the light curve after similar to 25 days, accompanied by a drastic change in the spectral energy distribution. The light curve and the spectral energy distribution are naturally interpreted as describing the emergence and subsequent decay of a supernova ( SN), similar to SN 1998bw. At peak luminosity, the SN is estimated to be 0.8 +/- 0.1 mag fainter than SN 1998bw. This argues in favor of the existence of a SN associated with this XRF. A spectrum obtained 35 days after the burst shows emission lines from the host galaxy. We use this spectrum to put an upper limit on the oxygen abundance of the host at [O/H] <= 0.6 dex. We also discuss a possible trend between the softness of several bursts and the early behavior of the optical afterglow, in the sense that XRFs and X-ray-rich gamma- ray bursts ( GRBs) seem to have a plateau phase or even a rising light curve. This can be naturally explained in models in which XRFs are similar to GRBs but are seen off the jet axis.
Y1  - 2006
UR  - http://iopscience.iop.org/0004-637X/
U6  - https://doi.org/10.1086/502640
SN  - 0004-637X
ER  - 
TY  - JOUR
A1  - de Jong, S.
A1  - Kukreja, R.
A1  - Trabant, C.
A1  - Pontius, N.
A1  - Chang, C. F.
A1  - Kachel, T.
A1  - Beye, Martin
A1  - Sorgenfrei, Nomi
A1  - Back, C. H.
A1  - Braeuer, B.
A1  - Schlotter, W. F.
A1  - Turner, J. J.
A1  - Krupin, O.
A1  - Doehler, M.
A1  - Zhu, D.
A1  - Hossain, M. A.
A1  - Scherz, A. O.
A1  - Fausti, D.
A1  - Novelli, F.
A1  - Esposito, M.
A1  - Lee, W. S.
A1  - Chuang, Y. D.
A1  - Lu, D. H.
A1  - Moore, R. G.
A1  - Yi, M.
A1  - Trigo, M.
A1  - Kirchmann, P.
A1  - Pathey, L.
A1  - Golden, M. S.
A1  - Buchholz, Marcel
A1  - Metcalf, P.
A1  - Parmigiani, F.
A1  - Wurth, W.
A1  - Föhlisch, Alexander
A1  - Schuessler-Langeheine, Christian
A1  - Duerr, H. A.
T1  - Speed limit of the insulator-metal transition in magnetite
JF  - Nature materials
N2  - As the oldest known magnetic material, magnetite (Fe3O4) has fascinated mankind for millennia. As the first oxide in which a relationship between electrical conductivity and fluctuating/localized electronic order was shown(1), magnetite represents a model system for understanding correlated oxides in general. Nevertheless, the exact mechanism of the insulator-metal, or Verwey, transition has long remained inaccessible(2-8). Recently, three- Fe- site lattice distortions called trimeronswere identified as the characteristic building blocks of the low-temperature insulating electronically ordered phase(9). Here we investigate the Verwey transition with pump- probe X- ray diffraction and optical reflectivity techniques, and show how trimerons become mobile across the insulator-metal transition. We find this to be a two- step process. After an initial 300 fs destruction of individual trimerons, phase separation occurs on a 1.5 +/- 0.2 ps timescale to yield residual insulating and metallic regions. This work establishes the speed limit for switching in future oxide electronics(10).
Y1  - 2013
U6  - https://doi.org/10.1038/NMAT3718
SN  - 1476-1122
SN  - 1476-4660
VL  - 12
IS  - 10
SP  - 882
EP  - 886
PB  - Nature Publ. Group
CY  - London
ER  - 
TY  - JOUR
A1  - Daly, J. S.
A1  - Balagansky, V. V.
A1  - Timmerman, Martin Jan
A1  - Whitehouse, M. J.
A1  - de Jong, K.
A1  - Guise, P.
A1  - Bogdanova, S.
A1  - Gorbatschev, R.
A1  - Bridgwater, D.
T1  - Ion microprobe U-Pb zircon geochronology and isotopic evidence for a trans-crustal suture in the Lapland-Kola Orogen, northern Fennoscandian Shield
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Brown, John C.
A1  - Barrett, R. K.
A1  - Oskinova, Lida
A1  - Owocki, S. P.
A1  - Hamann, Wolf-Rainer
A1  - de Jong, J. A.
A1  - Kaper, L.
A1  - Henrichs, H. F.
T1  - Inference of hot star density stream properties from data on rotationally recurrent DACs
N2  - The information content of data on rotationally periodic recurrent discrete absorption components (DACs) in hot star wind emission lines is discussed. The data comprise optical depths tau(w,phi) as a function of dimensionless Doppler velocity w=(Deltalambda/lambda(0))(c/v(infinity)) and of time expressed in terms of stellar rotation angle phi. This is used to study the spatial distributions of density, radial and rotational velocities, and ionisation structures of the corotating wind streams to which recurrent DACs are conventionally attributed. The simplifying assumptions made to reduce the degrees of freedom in such structure distribution functions to match those in the DAC data are discussed and the problem then posed in terms of a bivariate relationship between tau(w, phi) and the radial velocity v(r)(r), transverse rotation rate Omega(r) and density rho(r, phi) structures of the streams. The discussion applies to cases where: the streams are equatorial; the system is seen edge on; the ionisation structure is approximated as uniform; the radial and transverse velocities are taken to be functions only of radial distance but the stream density is allowed to vary with azimuth. The last kinematic assumption essentially ignores the dynamical feedback of density on velocity and the relationship of this to fully dynamical models is discussed. The case of narrow streams is first considered, noting the result of Hamann et al. (2001) that the apparent acceleration of a narrow stream DAC is higher than the acceleration of the matter itself, so that the apparent slow acceleration of DACs cannot be attributed to the slowness of stellar rotation. Thus DACs either involve matter which accelerates slower than the general wind flow, or they are formed by structures which are not advected with the matter flow but propagate upstream (such as Abbott waves). It is then shown how, in the kinematic model approximation, the radial speed of the absorbing matter can be found by inversion of the apparent acceleration of the narrow DAC, for a given rotation law. The case of broad streams is more complex but also more informative. The observed tau(w,phi) is governed not only by v(r)(r) and Omega(r) of the absorbing stream matter but also by the density profile across the stream, determined by the azimuthal (phi(0)) distribution function F- 0(phi(0)) of mass loss rate around the stellar equator. When F-0(phi(0)) is fairly wide in phi(0), the acceleration of the DAC peak tau(w, phi) in w is generally slow compared with that of a narrow stream DAC and the information on v(r)(r), Omega(r) and F-0(phi(0)) is convoluted in the data tau(w, phi). We show that it is possible, in this kinematic model, to recover by inversion, complete information on all three distribution functions v(r)(r), Omega(r) and F- 0(phi(0)) from data on tau(w, phi) of sufficiently high precision and resolution since v(r)(r) and Omega(r) occur in combination rather than independently in the equations. This is demonstrated for simulated data, including noise effects, and is discussed in relation to real data and to fully hydrodynamic models
Y1  - 2004
SN  - 0004-6361
ER  - 
TY  - JOUR
A1  - van Schaik, N. Loes M. B.
A1  - Bronstert, Axel
A1  - de Jong, S. M.
A1  - Jetten, V. G.
A1  - van Dam, J. C.
A1  - Ritsema, C. J.
A1  - Schnabel, Susanne
T1  - Process-based modelling of a headwater catchment in a semi-arid area: the influence of macropore flow
JF  - Hydrological processes
N2  - Subsurface stormflow is thought to occur mainly in humid environments with steep terrains. However, in semi-arid areas, preferential flow through macropores can also result in a significant contribution of subsurface stormflow to catchment runoff for varying catchment conditions. Most hydrological models neglect this important subsurface preferential flow. Here, we use the process-oriented hydrological model Hillflow-3D, which includes a macropore flow approach, to simulate rainfall-runoff in the semi-arid Parapunos catchment in Spain, where macropore flow was observed in previous research. The model was extended for this study to account for sorptivity under very dry soil conditions. The results of the model simulations with and without macropore flow are compared. Both model versions give reasonable results for average rainfall situations, although the approach with the macropore concept provides slightly better results. The model results for scenarios of extreme rainfall events (>13.3mm30min(-1)) however show large differences between the versions with and without macropores. These model results compared with measured rainfall-runoff data show that the model with the macropore concept is better. Our conclusion is that preferential flow is important in controlling surface runoff in case of specific, high intensity rainfall events. Therefore, preferential flow processes must be included in hydrological models where we know that preferential flow occurs. Hydrological process models with a less detailed process description may fit observed average events reasonably well but can result in erroneous predictions for more extreme events. Copyright (c) 2013 John Wiley & Sons, Ltd.
KW  - process based
KW  - macropore flow
KW  - catchment scale
KW  - modelling
KW  - semi-arid area
Y1  - 2014
U6  - https://doi.org/10.1002/hyp.10086
SN  - 0885-6087
SN  - 1099-1085
VL  - 28
IS  - 24
SP  - 5805
EP  - 5816
PB  - Wiley-Blackwell
CY  - Hoboken
ER  -