Search results for "Shock wave"

MODELING SNR CASSIOPEIA A from the SUPERNOVA EXPLOSION to ITS CURRENT AGE: The ROLE of POST-EXPLOSION ANISOTROPIES of EJECTA

2016

The remnants of core-collapse supernovae (SNe) have complex morphologies that may reflect asymmetries and structures developed during the progenitor SN explosion. Here we investigate how the morphology of the SNR Cassiopeia A (Cas A) reflects the characteristics of the progenitor SN with the aim to derive the energies and masses of the post-explosion anisotropies responsible for the observed spatial distribution of Fe and Si/S. We model the evolution of Cas A from the immediate aftermath of the progenitor SN to the three-dimensional interaction of the remnant with the surrounding medium. The post-explosion structure of the ejecta is described by small-scale clumping of material and larger-s…

Impact of self-steepening on incoherent dispersive spectral shocks and collapse-like spectral singularities

2014

International audience; Incoherent dispersive shock waves and collapselike singularities have been recently predicted to occur in the spectral evolution of an incoherent optical wave that propagates in a noninstantaneous nonlinear medium. Here we extend this work by considering the generalized nonlinear Schrödinger equation. We show that self-steepening significantly affects these incoherent spectral singularities: (i) It leads to a delay in the development of incoherent dispersive shocks, and (ii) it arrests the incoherent collapse singularity. Furthermore, we show that the spectral collapselike behavior can be exploited to achieve a significant enhancement (by two orders of magnitudes) of…

Laboratory evidence for asymmetric accretion structure upon slanted matter impact in young stars

2020

Aims. Investigating the process of matter accretion onto forming stars through scaled experiments in the laboratory is important in order to better understand star and planetary system formation and evolution. Such experiments can indeed complement observations by providing access to the processes with spatial and temporal resolution. A previous investigation revealed the existence of a two-component stream: a hot shell surrounding a cooler inner stream. The shell was formed by matter laterally ejected upon impact and refocused by the local magnetic field. That laboratory investigation was limited to normal incidence impacts. However, in young stellar objects, the complex structure of magne…

Supernova 1987A: a Template to Link Supernovae to their Remnants

2015

The emission of supernova remnants reflects the properties of both the progenitor supernovae and the surrounding environment. The complex morphology of the remnants, however, hampers the disentanglement of the two contributions. Here we aim at identifying the imprint of SN 1987A on the X-ray emission of its remnant and at constraining the structure of the environment surrounding the supernova. We performed high-resolution hydrodynamic simulations describing SN 1987A soon after the core-collapse and the following three-dimensional expansion of its remnant between days 1 and 15000 after the supernova. We demonstrated that the physical model reproducing the main observables of SN 1987A during …

Spatially Resolved Broadband Synchrotron Emission from the Nonthermal Limbs of SN1006

2018

We present ~400ks NuSTAR observations of the northeast (NE) and southwest (SW) non-thermal limbs of the Galactic SNR SN1006. We discovered three sources with X-ray emission detected at >50keV. Two of them are identified as background AGN. We extract the NuSTAR spectra from a few regions along the non-thermal limbs and jointly analyze them with the XMM-Newton spectra and the radio data. The broad-band radio/X-ray spectra can be well described with a synchrotron emission model from a single population of CR electrons with a power law energy distribution and an exponential cutoff. The power law index of the electron particle distribution function (PDF) is ~1.88-1.95 for both the NE and SW l…

‚ÄûExtracorporeal shock wave therapy for plantar fasciitis‚Äìa double blind randomised controlled trial‚Äù by C. A. Speed et al., J Orthop res 2003;2…

2004

Extrakorporale Stoßwellen-Lithotripsie von Gallensteinen und die Rolle der Gallenchirurgie

2009

Die Hochenergetische Extrakorporale Stoßwellentherapie (ESWT) in der Behandlung von Pseudarthrosen

2008

PROBLEM The success rate of high-energy extracorporal shock wave therapy in the treatment of non-unions in comparison to the "golden standard" surgery is still unclear. METHOD In a prospective study, 3000 impulses with an energy density of 0.6 mJ/mm2 were applied with an experimental device to the pseudarthrosis in 52 patients. RESULTS The mean duration of pseudarthrosis was 13 months. A mean of 2.5 surgical interventions had already been performed. Bony union was achieved in 52% of our patients after an average of 3.3 months. Failures especially were found in the atrophic type of pseudarthrosis as well as in congenital bone disorders like fibrous dysplasia or osteogenesis imperfecta. No se…

99mTechnetium-Mercaptoacetyltriglycin (MAG3) zum Nachweis von Nierenveränderungen nach extrakorporaler Stoßwellenlithotripsie

1992

Extracorporeal shock wave lithotripsy (ESWL) has become the treatment of choice for urinary calculi. 117 patients were studied prospectively with 99mTc mercaptoacetyltriglycine (MAG3) before and after ESWL. 79 (66%) of the 119 kidneys treated had abnormal findings. Of these 63/119 (53%) had abnormal scans. 41 (65%) had focal lesions with a delayed intrarenal transport. The remaining 22 had a diffuse delay of intrarenal transport. A loss of relative renal function of 3% and more compared to the pretreatment values was observed in 50/119 (42%) patients. 99mTc MAG3 should be done routinely together with radiologic tests (CT or MRI) before and after ESWL to select the patients at risk for post …

Extracorporeal shock wave lithotripsy of urinary calculi: experience in treatment of 3,278 patients using the Siemens Lithostar and Lithostar Plus.

1991

Between March 1986 and June 1989, 3,278 patients with upper urinary tract calculi were treated at our medical center with the Lithostar lithotriptor. The stones were located in the calices in 41.9% of the cases, renal pelvis in 25.7% and ureter in 32.4%. Perirenal hematoma was noted in 0.5% of the patients but this resolved spontaneously within a few days. Auxiliary procedures were performed in 37.3% of the cases, including Double-J stent and ureteral catheter in 26.8%, ureterorenoscopy in 2.1%, percutaneous nephrostomy in 1.6%, Zeiss loop in 4.3% and percutaneous nephrolithotripsy in 3.5%. Of the treatments 83.1% were performed without general or regional anesthesia. Followup after 3 month…