EXTENDED SOFT-X-RAY EMISSION IN THE SEYFERT-2 GALAXY NGC-4388 DISCOVERED WITH THE ROSAT HRI

Authors
MATT G PIRO L ANTONELLI LA FINK HH MEURS EJA PEROLA GC
Citation
G. Matt et al., EXTENDED SOFT-X-RAY EMISSION IN THE SEYFERT-2 GALAXY NGC-4388 DISCOVERED WITH THE ROSAT HRI, Astronomy and astrophysics, 292(2), 1994, pp. 120000013-120000016
Citations number
32
Categorie Soggetti
Astronomy & Astrophysics
Journal title
Astronomy and astrophysics → ACNP
ISSN journal
00046361
Volume
292
Issue
2
Year of publication
1994
Pages
120000013 - 120000016
Database
ISI
SICI code
0004-6361(1994)292:2<120000013:ESEITS>2.0.ZU;2-4
Abstract
Extended (R similar to 4.5 kpc) X-ray emission in the Seyfert 2 galaxy NGC 4388 has been discovered with the ROSAT HRI. No evidence for a nu clear, unresolved component has been found; the upper limit for such a component is about 20% of the total flux. The interpretation of the e xtended emission in terms of nuclear radiation scattered by a plasma i onized by the nuclear photons can be excluded on the basis of a simple photoionization calculation. The two most likely alternatives, i.e. t hermal emission from a collisionally heated plasma and the sum from ma ny unresolved discrete sources, are briefly discussed.