J/ApJ/934/L37ivo://CDS.VizieR/J/ApJ/934/L37doi:10.26093/cds/vizier.19349037CDSMontano J.W.Guo H.Barth A.J.Vivian U.Remigio R.,Gonzalez-Buitrago D.H.Hernandez Santisteban J.V.2025-05-21T20:14:31Z2025-03-26T15:15:28ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frseyfert-galaxiesinfrared-photometryvisible-astronomybroad-band-photometryIn order to constrain the size of the optical continuum emission region in the dwarf Seyfert 1 galaxy NGC 4395 through reverberation mapping, we carried out high-cadence photometric monitoring in the griz filter bands on two consecutive nights in 2022 April using the four-channel MuSCAT3 camera on the Faulkes Telescope North at Haleakala Observatory. Correlated variability across the griz bands is clearly detected, and the r-, i-, and z-band light curves show lags of 7.72_-1.09_^+1.01^, 14.16_-1.25_^+1.22^, and 20.78_-2.09_^+1.99^min with respect to the g band when measured using the full-duration light curves. When lags are measured for each night separately, the Night 2 data exhibit lower cross-correlation amplitudes and shorter lags than the Night 1 light curves. Using the full-duration lags, we find that the lag-wavelength relationship is consistent with the {tau}{propto}{lambda}^4/3^ dependence found for more luminous active galactic nuclei. Combining our results with continuum lags measured for other objects, the lag between g and z band scales with optical continuum luminosity as {tau}_gz_{propto}L^0.56+/-0.05^, similar to the scaling of broad-line region size with luminosity, reinforcing recent evidence that diffuse continuum emission from the broad-line region may contribute substantially to optical continuum variability and reverberation lags.2022ApJ...934L..37Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/934/L37CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/ApJ/632/799 : NGC4395 light curves (Peterson+, 2005)J/ApJ/650/88 : NGC4395 light curves. III. (Desroches+, 2006)J/ApJ/756/73 : gri LCs of the low-luminosity AGN NGC 4395 (Edri+, 2012)J/ApJ/821/56 : Space telescope RM project. III. NGC5548 LCs (Fausnaugh+, 2016)J/ApJ/840/41 : X-ray/UV Swift monitoring of NGC 4151 (Edelson+, 2017)J/ApJ/854/107 : Light curves of 2 Seyfert 1 galaxies (Fausnaugh+, 2018)J/ApJ/870/123 : Swift optical & UV flux of four AGNs (Edelson+, 2019)J/ApJ/899/136 : TESS light curve of AGN NGC 4395 (Burke+, 2020)J/ApJ/896/1 : SEAMBHs. XI. Mrk142 X-ray to opt. light curves (Cackett+, 2020)J/ApJ/892/93 : UV-NIR monitoring campaign of NGC 4395 (Cho+, 2020)J/ApJ/903/112 : SDSS Hb & CIV reverberation mapped AGNs (Dalla Bonta+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/934/L37https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/934/L37http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/934/L37https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/934/L37https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/934/L37http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/934/L37GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalInfrareddefaultJ/ApJ/934/L37/table1NGC 4395 FTN/MuSCAT3 photometryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFilt[griz] Filtermeta.id;instr.filtercharHJD[0.26/1.55] Heliocentric Julian Date; HJD-2459695dtime.epochfloatFlux[0.44/1.32] Flux in units of 10^-15^erg/cm^2^/s/{AA}cW.m**-2.nm**-1phot.flux.densityfloate_Flux[0.002/0.007] Uncertainty in FluxcW.m**-2.nm**-1stat.error;phot.flux.densityfloat