1 / 14

Shock-cloud interaction in the Vela SNR: the XMM-Newton view

Shock-cloud interaction in the Vela SNR: the XMM-Newton view. M. Miceli 1 , F. Bocchino 2 , A. Maggio 2 , F. Reale 1 1.Dipartimento di Scienze Fisiche ed Astronomiche, Universit à di Palermo 2. INAF-Osservatorio Astronomico G. S. Vaiana di Palermo. Low spatial resolution (> 5’).

diza
Télécharger la présentation

Shock-cloud interaction in the Vela SNR: the XMM-Newton view

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Shock-cloud interaction in the Vela SNR: the XMM-Newton view M. Miceli1, F. Bocchino2, A. Maggio2, F. Reale1 1.Dipartimento di Scienze Fisiche ed Astronomiche, Università di Palermo 2. INAF-Osservatorio Astronomico G. S. Vaiana di Palermo

  2. Low spatial resolution (> 5’). Low Aeff. Low spectral resolution (E/DE < 2) Low Aeff. Geometry of the system? No detailed comparison between X-ray and optical emission. Difficulty in estimating the physical parameters of the plasma. Detecting NEI effects. Interaction between the blast-wave shock of a middle-aged SNR and the inhomogeneities of the ISM. The analysis of past X-ray observations left many open issues: Impossibility of unambiguously describing the physics of the shock-cloud interaction.

  3. Thedata • Guaranteed Time Observation. • Coordinates: a (2000)=8h35m44s; d (2000) = -42º35’29’’. • Exposure time: 26.8 ksec (PN); 31.1 ksec (MOS). • Mode: Extended Full Frame (PN); Large Window (MOS). • Filter: Medium.

  4. Our aims: • Describing the morphology of the ISM clouds (shape, dimension, spatial distribution…). • Obtaining information about the physical properties and the internal structure of the clouds. • Studying the dynamics and the evolution of the shock-cloud interaction. ROSAT All Sky Survey (0.2-2.4 keV)

  5. EPIC count rate images RegNE ~ 2.4 pc 0 cnt/s 7.210-5 0 cnt/s 10-4 FilD

  6. Comparison between X-ray and optical emission in the FilD region • Color coding: • Green: Ha emission • Violet: OIII emission • Red: X-ray contour levels (0.3-0.5 keV) Maximum X-ray contour levels are just outside the optical filament: the optical emission follows a path that grazes, without crossing, the brightest X-ray FilD regions.

  7. Regions selected for spectral analysis 0.3-2 keV • Color coding: • Black: FilD • Red: South-Western region • Blue: RegNE In each region the mean photon energy E has low fluctuations: DE/Eavg  0.04

  8. Spectral analysis Representative folded spectrum O/O= 1.0 ± 0.1 Ne/Ne = 1.7 ± 0.2 Fe/Fe = 0.39 ± 0.05 All spectra are well described by two MEKAL components

  9. TII (106 K) TI (106 K) cnt/s The values of the temperature of both components don’t show significant variations in the field of view.

  10. nII2LII (1017 cm-5) nI2LI (1017 cm-5) cnt/s For both components the product n2L (where n is the particle density and L is the extension along the line of sight) presents huge inhomogeneities in the field of view.

  11. Evolution of the shocked clouds n = 0.5  1.9 cm-3 T  3.0  106 K Corona: trad> tcond Evaporation Collapse n = 3.2  8.2 cm-3 T = 3  10  104 K Optical filament: n = 1.4  5 cm-3 T  1.14  106 K Core: trad< tcond n < 0.07 cm-3 Intercloud medium: T = 4  8  106 K trad> tcond

  12. cores: radiative cooling collapse coronae: thermal conduction evaporation Conclusions: • We resolved different phases in ISM clouds. • 3-D map of the observed clouds (FilD mass  1031g for a core particle density of 2 cm-3). • Discriminate model (no reflected shocks). • Evolution of the shocked clouds

More Related