Computer Science
Scientific paper
Sep 1987
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1987phdt........76c&link_type=abstract
Thesis (PH.D.)--UNIVERSITY OF HAWAII, 1987.Source: Dissertation Abstracts International, Volume: 48-10, Section: B, page: 3000.
Computer Science
1
Scientific paper
Kinetics of N^{+} were mapped across the Seyfert-like narrow-line region (9" radius) at the center of the active spiral galaxy M51 (NGC 5194). A CCD and imaging Fabry-Perot interferometer were used in sub-arcsecond seeing at 60 kms^ {-1} resolution. Two Hα velocity channels were also recorded. Complementary long-slit CCD spectroscopy provides S^{+ } densities and N^{+} profiles of high signal-to-noise ratio at sub-arcsecond increments. Line emission, line width, gas excitation and radio continua peak in a spatially resolved, extranuclear cloud (XNC) ~4" south of the nucleus. Here, line profiles and channel maps show N^{+ } emission enhanced in a shell of unresolved thickness (<40 pc). The Hα distribution is more uniform, indicating N ^{+} enhancement through temperature/ionization variations rather than by mass. Velocities are highest along a bright, arcuate surface on the southeastern boundary of this shell. The surface opens toward the interior of the XNC and incorporates ~4000 M_odot of ionized gas with velocity dispersion ~140 kms ^{-1}. The nucleus is ellipsoidal in line emission and radio continua, with major axis aimed at this surface. The emission morphology, excitation distribution, and positional variation of the N^{+ } kinematics in the XNC plausibly arise from the interaction of an ongoing collimated nuclear outflow with the ambient media. The kinematics are deprojected to show that the region of highest velocity gas is expanding at ~500 kms^{ -1} into these media. Here two cloud systems are projected on the sight-line to produce line widths of ~1500 kms^{ -1}. Their expansion apparently arises from thermalization of the outflow kinetic energy at shock fronts. Models of high-velocity, planar shocks can fully account for the observed Hα luminosity only if the ambient density is >100 cm ^{-3}. Thus a central photoionizing source is necessary if the ambient density is confirmed to be ~1 cm^{ -3}, as implied by the HI column in the region of the XNC. The flow may deflect to produce a secondary, "splatter" spot along the southern boundary of the XNC, where gas velocities are lower and the (NII) /H alpha ratio attains its maximum value in the NLR. This enhancement is velocity-dependent and occurs in a region occupied by nonthermal particles.
No associations
LandOfFree
Kinematics of Spatially Extended High-Velocity Outflow from the Nucleus of M51. does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Kinematics of Spatially Extended High-Velocity Outflow from the Nucleus of M51., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Kinematics of Spatially Extended High-Velocity Outflow from the Nucleus of M51. will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1677230