Dark Cosmology Centre l Niels Bohr institute l Copenhagen University A deep VLT study of extended Lyman- emission from QSOs Johan P. U. Fynbo -Background: a spin-off project (in progress) -What we see -Physical origin?

2 Background: Palle Møller Bjarne Thomsen Michael Weidinger It all started 10 years ago with our wish to study the associated absorber towards Q Collaborators:

3 NTT 1998 results on Q

4 VLT 2000 results on Q The extended emission was not from the absorber, but from the QSO.

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6 How common is this? Next step is to build a sample!

7 Spectra

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9 1d spectra, SB profiles and velocity profiles

10 General properties Sizes 1-10 kpc scale length km s -1 velocity widths. No associated CIV and HeII emission.

11 Comparison with literature: Literature sample: 17 RLQs, 5 RQQs Extended Lyman- emission from RQQs is on average fainter, smaller and has narrower velocity width (up to publication bias) than such emission from RLQs. For RLQs CIV and HeII is often detected, but in no case from a RQQ in our sample. Different physical origin? Jet interaction vs. Cold accretion? More work needed. Link to Lyman- blobs?

Summary In the sample of 14 QSOs (3 radio-loud) we detect extended emission from 8 (2 radio-loud). Comparing with the literature on extended emission from radio loud QSOs the extended emission from radio quiet QSOs seems to have a different physical origin. (This is still work in progress - hopefully to be completed this summer) Thanks for your attention

13 The narrow band filter

14 NTT 1998 results