OBSERVATIONS OF OUTFLOWING ULTRAVIOLET ABSORBERS IN NGC 4051 WITH THE COSMIC ORIGINS SPECTROGRAPH

Journal Article · Fri Jun 01 04:00:00 EDT 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/751/2/84· OSTI ID:22037208

Kraemer, S B ^[1]; Crenshaw, D M; Fischer, T C ^[2]; Dunn, J P ^[3]; Turner, T J ^[4]; Lobban, A P; Reeves, J N ^[5]; Miller, L ^[6]; Braito, V ^[7]

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1. Institute for Astrophysics and Computational Sciences, Department of Physics, Catholic University of America, Washington, DC 20064 (United States)
2. Department of Physics and Astronomy, Georgia State University, Astronomy Offices, One Park Place South SE, Suite 700, Atlanta, GA 30303 (United States)
3. Department of Chemistry and Physics, Augusta State University, 2500 Walton Way, Augusta, GA 30904 (United States)
4. Department of Physics, University of Maryland Baltimore County, Baltimore, MD 21250 (United States)
5. Astrophysics Group, School of Physical and Geographical Sciences, Keele University, Keele, Staffordshire ST5 5BG (United Kingdom)
6. Department of Physics, University of Oxford, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH (United Kingdom)
7. Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH (United Kingdom)

We present new Hubble Space Telescope (HST)/Cosmic Origins Spectrograph (COS) observations of the narrow-line Seyfert 1 galaxy NGC 4051. These data were obtained as part of a coordinated observing program including X-ray observations with the Chandra/High Energy Transmission Grating (HETG) spectrometer and Suzaku. We detected nine kinematic components of UV absorption, which were previously identified using the HST/Space Telescope Imaging Spectrograph (STIS). None of the absorption components showed evidence for changes in column density or profile within the {approx}10 yr between the STIS and COS observations, which we interpret as evidence of (1) saturation, for the stronger components, or (2) very low densities, i.e., n{sub H} < 1 cm{sup -3}, for the weaker components. After applying a +200 km s{sup -1} offset to the HETG spectrum, we found that the radial velocities of the UV absorbers lay within the O VII profile. Based on photoionization models, we suggest that, while UV components 2, 5, and 7 produce significant O VII absorption, the bulk of the X-ray absorption detected in the HETG analysis occurs in more highly ionized gas. Moreover, the mass-loss rate is dominated by high-ionization gas which lacks a significant UV footprint.

• OSTI ID: 22037208
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 751; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ABSORPTION
ASTROPHYSICS
DENSITY
GAMMA ASTRONOMY
PHOTOIONIZATION
RADIAL VELOCITY
SEYFERT GALAXIES
TELESCOPES
ULTRAVIOLET RADIATION
X RADIATION
X-RAY SPECTRA
X-RAY SPECTROMETERS