Measurement of the broad-line region size in two bright quasars

Shai Kaspi, Paul S. Smith, Dan Maoz, Hagai Netzer, Buell Tomasson Jannuzi

Research output: Contribution to journalArticle

45 Citations (Scopus)

Abstract

We present 4 years of spectrophotometric monitoring data for two radio-quiet quasars, PG 0804+762 and PG 0953+414, with typical sampling intervals of several months. Both sources show continuum and emission-line variations. The variations of the Hβ line follow those of the continuum with a time lag, as derived from a cross-correlation analysis, of 93 ± 30 days for PG 0804+762 and 111 ± 55 days for PG 0953+414. This is the first reliable measurement of such a lag in active galactic nuclei with luminosity L > 1045 ergs s-1. The broad-line region (BLR) size that is implied is almost an order of magnitude larger than that measured in several Seyfert 1 galaxies and is consistent with the hypothesis that the BLR size grows as L0.5.

Original languageEnglish (US)
JournalAstrophysical Journal
Volume471
Issue number2 PART II
StatePublished - 1996
Externally publishedYes

Fingerprint

quasars
time lag
continuums
H lines
active galactic nuclei
erg
cross correlation
sampling
luminosity
radio
galaxies
intervals
analysis
monitoring data

Keywords

  • Galaxies: active
  • Quasars: emission lines

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Kaspi, S., Smith, P. S., Maoz, D., Netzer, H., & Jannuzi, B. T. (1996). Measurement of the broad-line region size in two bright quasars. Astrophysical Journal, 471(2 PART II).

Measurement of the broad-line region size in two bright quasars. / Kaspi, Shai; Smith, Paul S.; Maoz, Dan; Netzer, Hagai; Jannuzi, Buell Tomasson.

In: Astrophysical Journal, Vol. 471, No. 2 PART II, 1996.

Research output: Contribution to journalArticle

Kaspi, S, Smith, PS, Maoz, D, Netzer, H & Jannuzi, BT 1996, 'Measurement of the broad-line region size in two bright quasars', Astrophysical Journal, vol. 471, no. 2 PART II.
Kaspi, Shai ; Smith, Paul S. ; Maoz, Dan ; Netzer, Hagai ; Jannuzi, Buell Tomasson. / Measurement of the broad-line region size in two bright quasars. In: Astrophysical Journal. 1996 ; Vol. 471, No. 2 PART II.
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