J/ApJ/870/123 Swift optical & UV flux of four AGNs (Edelson+, 2019)
The first Swift intensive AGN accretion disk reverberation mapping survey.
Edelson R., Gelbord J., Cackett E., Peterson B.M., Horne K., Barth A.J.,
Starkey D.A., Bentz M., Brandt W.N., Goad M., Joner M., Korista K.,
Netzer H., Page K., Uttley P., Vaughan S., Breeveld A., Cenko S.B.,
Done C., Evans P., Fausnaugh M., Ferland G., Gonzalez-Buitrago D.,
Gropp J., Grupe D., Kaastra J., Kennea J., Kriss G., Mathur S.,
Mehdipour M., Mudd D., Nousek J., Schmidt T., Vestergaard M., Villforth C.
<Astrophys. J., 870, 123-123 (2019)>
=2019ApJ...870..123E 2019ApJ...870..123E (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei; Galaxies, Seyfert;
Photometry, UBV; Photometry, ultraviolet; X-ray sources
Keywords: galaxies: active; galaxies: nuclei; galaxies: Seyfert
Abstract:
Swift intensive accretion disk reverberation mapping of four AGN
yielded light curves sampled ∼200-350 times in 0.3-10keV X-ray and six
UV/optical bands. Uniform reduction and cross-correlation analysis of
these data sets yields three main results: (1) The X-ray/UV
correlations are much weaker than those within the UV/optical, posing
severe problems for the lamp-post reprocessing model in which
variations in a central X-ray corona drive and power those in the
surrounding accretion disk. (2) The UV/optical interband lags are
generally consistent with τ∝λ4/3 as predicted by
the centrally illuminated thin accretion disk model. While the average
interband lags are somewhat larger than predicted, these results alone
are not inconsistent with the thin disk model given the large
systematic uncertainties involved. (3) The one exception is the U band
lags, which are on average a factor of ∼2.2 larger than predicted from
the surrounding band data and fits. This excess appears to be due to
diffuse continuum emission from the broad-line region (BLR). The
precise mixing of disk and BLR components cannot be determined from
these data alone. The lags in different AGN appear to scale with mass
or luminosity. We also find that there are systematic differences
between the uncertainties derived by Just Another Vehicle for
Estimating Lags In Nuclei (JAVELIN) versus more standard lag
measurement techniques, with JAVELIN reporting smaller uncertainties
by a factor of 2.5 on average. In order to be conservative only
standard techniques were used in the analyses reported herein.
Description:
This paper presents a systematic reduction and analysis of the
intensive disk reverberation mapping (IDRM) data on four AGN in order
to survey their interband cross-correlation properties and test the
standard thin accretion disk/reprocessing picture.
The first Swift IDRM target was NGC 5548 (Edelson+ 2015, J/ApJ/806/129
and Fausnaugh+ 2016, J/ApJ/821/56). Subsequent IDRM campaigns also
detected clear interband UV/optical lags in the nearby NGC 4151
(Edelson et al. 2017) and NGC 4593 (McHardy et al. 2018).
IDRM monitoring of Mrk 509 was completed in 2017 December; we report
on these results for the first time in this contribution.
The four Swift IDRM campaigns reported herein are all designed in a
broadly similar fashion, with ∼200-350 visits and UVOT sampling in all
six filters (covering the UV/optical from 1928 to 5468Å).
Source and campaign parameters for these four IDRM AGN are given in
Table1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 53 4 Intensive disk reverberation mapping (IDRM)
AGN source and campaign parameters
table2.dat 60 7713 Swift-UVOT and Swift-XRT fluxes
table8.dat 18 64 UV mask boxes
table9.dat 18 11 Optical mask boxes
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See also:
J/ApJ/613/682 : AGN central masses & broad-line region sizes (Peterson+, 2004)
J/ApJ/622/129 : Lag-luminosity relationship in AGN (Sergeev+, 2005)
J/ApJ/681/113 : Swift BAT survey of AGNs (Tueller+, 2008)
J/ApJ/698/895 : Variations in QSOs optical flux (Kelly+, 2009)
J/MNRAS/397/1177 : Swift-XRT observations of GRBs (Evans+, 2009)
J/ApJ/753/L2 : Reverberation mapping of AGNs (Assef+, 2012)
J/ApJ/755/60 : Reverberation mapping for 5 Seyfert 1 galaxies (Grier+, 2012)
J/ApJ/788/48 : X-ray through NIR photometry of NGC 2617 (Shappee+, 2014)
J/ApJ/795/149 : Reverberation mapping of Seyfert 1 NGC 7469 (Peterson+, 2014)
J/ApJ/801/45 : QSOs properties & reverberation mapping (Hernitschek+, 2015)
J/ApJ/806/129 : Space telescope RM project. II. Swift data (Edelson+, 2015)
J/ApJ/821/56 : Space telescope RM project. III. NGC5548 LCs (Fausnaugh+, 2016)
J/ApJ/827/118 : A new reverberation mapping campaign on NGC 5548 (Lu+, 2016)
J/ApJ/840/41 : X-ray/UV Swift monitoring of NGC 4151 (Edelson+, 2017)
J/ApJ/840/97 : Reverberation mapping campaign of 5 AGNs (Fausnaugh+, 2017)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Name Name of the observed object
9- 14 F6.4 --- z [0.003/0.04] Redshift from SIMBAD database
16- 19 F4.2 [Msun] logBHM [6.8/8.1] Black hole mass from the AGN black hole
mass database (log10(MBH/M☉) (1)
21 I1 % fEdd [1/8] Eddington ratio (dm/dtEdd=Lbol/LEdd)
23- 29 F7.1 d MJD1 [56706/57830] Modified Julian Date at the
beginning of the campaign (JD-2400000.5)
31- 37 F7.1 d MJD2 [56833/58103] Modified Julian Date at the end of
the campaign (JD-2400000.5)
39- 43 F5.1 d Dur [22/273] Campaign duration
45- 47 I3 --- N [194/322] Total number of visits in which usable
data were gathered in at least one band
49- 53 F5.3 d Samp [0.1/1.1] Mean sampling interval based on the
campaign duration and the number of visits
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Note (1): The AGN black hole Mass Database is described in
Bentz & Katz, 2015PASP..127...67B 2015PASP..127...67B
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Name Object Name
9- 10 A2 --- Filt Filter/band used for Flux (Swift/UVOT:
U,B,V,W1,W2,M2 or Swift/XRT:
HX (1.5-10keV) or SX (0.3-1.5keV))
12- 15 I4 --- CNum [1001/4194] Cadence number (1)
17- 27 F11.5 d MJD [56705/58102.5] Modified Julian Date
at the midpoint of the exposure
(JD-2400000.5)
29- 36 F8.3 s Exp [23/1673] Duration of exposure in filter
38- 42 F5.3 10-16W/m2/nm Fuvot [0.8/6.9]? Mean Swift/UVOT flux
in units of 10-14erg/cm2/s/Å
44- 48 F5.3 10-16W/m2/nm e_Fuvot [0.01/0.7]? Uncertainty in Fuvot
50- 54 F5.3 ct/s FX [0.05/2.6]? Mean Swift/XRT flux
56- 60 F5.3 ct/s e_FX [0.01/0.2]? Uncertainty in FX
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Note (1): Cadence number, where the most significant digit refers to the
object and the next three refer to the visit number for that object.
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Mask [1/64] UV mask box number
4- 6 I3 pix X1 [317/729] X pixel range, start (G1)
8- 10 I3 pix X2 [326/736] X pixel range, end (G1)
12- 14 I3 pix Y1 [265/671] Y pixel range, start (G1)
16- 18 I3 pix Y2 [269/692] Y pixel range, end (G1)
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Mask [1/11] Optical mask box number
4- 6 I3 pix X1 [359/5361] X pixel range, start (G1)
8- 10 I3 pix X2 [377/577] X pixel range, end (G1)
12- 14 I3 pix Y1 [439/650] Y pixel range, start (G1)
16- 18 I3 pix Y2 [447/657] Y pixel range, end (G1)
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Global notes:
Note (G1): The X#, Y# coordinates are the X and Y ranges spanned by
rectangular boxes drawn in the reference frame of raw optical images
with the default 2x2 binning (with pixels numbered from 0 to 1023).
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History: From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS] 12-Feb-2020