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Titolo:
Intermediate resolution H beta spectroscopy and photometric monitoring of 3C 390.3 - I. Further evidence of a nuclear accretion disk
Autore:
Shapovalova, AI; Burenkov, AN; Carrasco, L; Chavushyan, VH; Doroshenko, VT; Dumont, AM; Lyuty, VM; Valdes, JR; Vlasuyk, VV; Bochkarev, NG; Collin, S; Legrand, F; Mikhailov, VP; Spiridonova, OI; Kurtanidze, O; Nikolashvili, MG;
Indirizzi:
Inst Nacl Astrofis Opt & Elect, Puebla 72000, Mexico Inst Nacl Astrofis Opt & Elect Puebla Mexico 72000 Puebla 72000, Mexico Russian Acad Sci, Special Astrophys Observ, Nizhnii Arkhyz 369167, Karachaevo Cher, Russia Russian Acad Sci Nizhnii Arkhyz Karachaevo Cher Russia 369167 her, Russia UNAM, Observ Astron Nacl, Ensenada 22860, Baja California, Mexico UNAM Ensenada Baja California Mexico 22860 22860, Baja California, Mexico Moscow MV Lomonosov State Univ, Sternberg Astron Inst, Moscow 119899, Russia Moscow MV Lomonosov State Univ Moscow Russia 119899 oscow 119899, Russia Observ Paris, DAEC, F-92195 Meudon, France Observ Paris Meudon France F-92195 v Paris, DAEC, F-92195 Meudon, France Georgian AS, Abastumani Astrophys Observ, GE-383762 Abastumani, Rep of Georgia Georgian AS Abastumani Rep of Georgia GE-383762 astumani, Rep of Georgia Isaac Newton Inst Chile, SAO Branch, Santiago, Chile Isaac Newton Inst Chile Santiago Chile ile, SAO Branch, Santiago, Chile
Titolo Testata:
ASTRONOMY & ASTROPHYSICS
fascicolo: 3, volume: 376, anno: 2001,
pagine: 775 - 792
SICI:
1432-0746(200109)376:3<775:IRHBSA>2.0.ZU;2-D
Fonte:
ISI
Lingua:
ENG
Soggetto:
ACTIVE GALACTIC NUCLEI; BROAD-LINE REGION; SHORT-TIMESCALE VARIABILITY; SEYFERT-GALAXY NGC-5548; EMISSION-LINE; RADIO GALAXY; MULTIWAVELENGTH OBSERVATIONS; X-RAY; CONTINUUM EMISSION; ULTRAVIOLET OBSERVATIONS;
Keywords:
galaxies : active; galaxies : Seyfert; galaxies : individual (3C 390.3); line : profiles;
Tipo documento:
Review
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
105
Recensione:
Indirizzi per estratti:
Indirizzo: Carrasco, L Inst Nacl Astrofis Opt & Elect, Apartado Postal 51, Puebla 72000, Mexico Inst Nacl Astrofis Opt & Elect Apartado Postal 51 Puebla Mexico72000
Citazione:
A.I. Shapovalova et al., "Intermediate resolution H beta spectroscopy and photometric monitoring of 3C 390.3 - I. Further evidence of a nuclear accretion disk", ASTRON ASTR, 376(3), 2001, pp. 775-792

Abstract

We have monitored the AGN 3C 390.3 between 1995 and 2000. A historical B-band light curve dating back to 1966 shows a large increase in brightness during 1970-1971, followed by a gradual decrease down to a minimum in 1982. During the 1995-2000 lapse the broad H beta emission and the continuum flux varied by a factor of approximate to 3. Two large amplitude outbursts, of different duration, in continuum and H beta light were observed i.e.: in October 1994 a brighter are that lasted approximate to 1000 days and in July 1997 another one that lasted approximate to 700 days were detected. The response time lag of the emission lines relative to flux changes of the continuum has been found to vary with time i.e. during 1995{1997 a lag of about 100 days is evident, while during 1998-1999 a double valued lag of approximate to 100 days and approximate to 35 days is present in our data. The flux in the H beta wings and line core vary simultaneously, a behavior indicativeof predominantly circular motions in the BLR. Important changes of the H beta emission profiles were detected: at times, we found profiles with prominent asymmetric wings, like those normaly seen in Sy1s, while at other times, we observe profiles with weak, almost symmetrical wings, similar to those of Sy1.8s. We further dismiss the hypothesis that the double peaked H beta profiles in this object originate in a massive binary BH. Instead, we found that the radial velocity difference between the red and blue bumps is anticorrelated with the light curves of H beta and continuum radiation. This implies that the zone that contributes most of the energy to the emitted line changes in radius within the disk. The velocity difference increases, corresponding to smaller radii, as the continuum flux decreases. When the continuum flux increases the hump velocity difference decreases. These transient phenomena are expected to result from the variable accretion rate close to the central source. The optical continuum and the H beta flux variationsmight be related to changes in X-ray emission modulated by a variable accretion rate, changing the surface temperature of the disk, as a result of a variable X-ray irradiation (Ulrich 2000). Theoretical H beta profiles were computed for an accretion disk, the observed profiles are best reproduced by an inclined disk (25 degrees) whose region of maximum emission is locatedroughly at 200 R-g. The mass of the black hole in 3C 390.3, estimated fromthe reverberation analysis is M-rev approximate to 2.1 x 10(9) M-., 5 times larger than previous estimates (Wandel et al. 1999).
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Documento generato il 24/05/13 alle ore 11:59:34