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Title: Space Telescope and Optical Reverberation Mapping Project. VIII. Time Variability of Emission and Absorption in NGC 5548 Based on Modeling the Ultraviolet Spectrum

Abstract

We model the ultraviolet spectra of the Seyfert 1 galaxy NGC 5548 obtained with the Hubble Space Telescope during the 6 month reverberation mapping campaign in 2014. Our model of the emission from NGC 5548 corrects for overlying absorption and deblends the individual emission lines. Using the modeled spectra, we measure the response to continuum variations for the deblended and absorption-corrected individual broad emission lines, the velocity-dependent profiles of Ly$α$ and C iv, and the narrow and broad intrinsic absorption features. We find that the time lags for the corrected emission lines are comparable to those for the original data. The velocity-binned lag profiles of Ly$α$ and C iv have a double-peaked structure indicative of a truncated Keplerian disk. The narrow absorption lines show a delayed response to continuum variations corresponding to recombination in gas with a density of ~10 5 cm -3. The high-ionization narrow absorption lines decorrelate from continuum variations during the same period as the broad emission lines. Analyzing the response of these absorption lines during this period shows that the ionizing flux is diminished in strength relative to the far-ultraviolet continuum. The broad absorption lines associated with the X-ray obscurer decrease in strength during this samemore » time interval. The appearance of X-ray obscuration in ~2012 corresponds with an increase in the luminosity of NGC 5548 following an extended low state. We suggest that the obscurer is a disk wind triggered by the brightening of NGC 5548 following the decrease in size of the broad-line region during the preceding low-luminosity state.« less

Authors:
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Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
Contributing Org.:
Gravity Collaboration
OSTI Identifier:
1562500
Grant/Contract Number:  
AC02-76SF00515
Resource Type:
Accepted Manuscript
Journal Name:
The Astrophysical Journal (Online)
Additional Journal Information:
Journal Name: The Astrophysical Journal (Online); Journal Volume: 881; Journal Issue: 2; Journal ID: ISSN 1538-4357
Publisher:
Institute of Physics (IOP)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; galaxies: active; galaxies: individual (NGC 5548); galaxies: nuclei; galaxies: Seyfert

Citation Formats

Kriss, G. A., De Rosa, G., Ely, J., Peterson, B. M., Kaastra, J., Mehdipour, M., Ferland, G. J., Dehghanian, M., Mathur, S., Edelson, R., Korista, K. T., Arav, N., Barth, A. J., Bentz, M. C., Brandt, W. N., Crenshaw, D. M., Bontà, E. Dalla, Denney, K. D., Done, C., Eracleous, M., Fausnaugh, M. M., Gardner, E., Goad, M. R., Grier, C. J., Horne, Keith, Kochanek, C. S., McHardy, I. M., Netzer, H., Pancoast, A., Pei, L., Pogge, R. W., Proga, D., Silva, C., Tejos, N., Vestergaard, M., Adams, S. M., Anderson, M. D., Arévalo, P., Beatty, T. G., Behar, E., Bennert, V. N., Bianchi, S., Bigley, A., Bisogni, S., Boissay-Malaquin, R., Borman, G. A., Bottorff, M. C., Breeveld, A. A., Brotherton, M., Brown, J. E., Brown, J. S., Cackett, E. M., Canalizo, G., Cappi, M., Carini, M. T., Clubb, K. I., Comerford, J. M., Coker, C. T., Corsini, E. M., Costantini, E., Croft, S., Croxall, K. V., Deason, A. J., De Lorenzo-Cáceres, A., De Marco, B., Dietrich, M., Di Gesu, L., Ebrero, J., Evans, P. A., Filippenko, A. V., Flatland, K., Gates, E. L., Gehrels, N., Geier, S., Gelbord, J. M., Gonzalez, L., Gorjian, V., Grupe, D., Gupta, A., Hall, P. B., Henderson, C. B., Hicks, S., Holmbeck, E., Holoien, T. W. -S., Hutchison, T. A., Im, M., Jensen, J. J., Johnson, C. A., Joner, M. D., Kaspi, S., Kelly, B. C., Kelly, P. L., Kennea, J. A., Kim, M., Kim, S. C., Kim, S. Y., King, A., Klimanov, S. A., Krongold, Y., Lau, M. W., Lee, J. C., Leonard, D. C., Li, Miao, Lira, P., Lochhaas, C., Ma, Zhiyuan, MacInnis, F., Malkan, M. A., Manne-Nicholas, E. R., Matt, G., Mauerhan, J. C., McGurk, R., Montuori, C., Morelli, L., Mosquera, A., Mudd, D., Müller-Sánchez, F., Nazarov, S. V., Norris, R. P., Nousek, J. A., Nguyen, M. L., Ochner, P., Okhmat, D. N., Paltani, S., Parks, J. R., Pinto, C., Pizzella, A., Poleski, R., Ponti, G., Pott, J. -U., Rafter, S. E., Rix, H. -W., Runnoe, J., Saylor, D. A., Schimoia, J. S., Schnülle, K., Scott, B., Sergeev, S. G., Shappee, B. J., Shivvers, I., Siegel, M., Simonian, G. V., Siviero, A., Skielboe, A., Somers, G., Spencer, M., Starkey, D., Stevens, D. J., Sung, H. -I., Tayar, J., Teems, K. G., Treu, T., Turner, C. S., Uttley, P., Van Saders, J. .., Vican, L., Villforth, C., Villanueva Jr., S., Walton, D. J., Waters, T., Weiss, Y., Woo, J. -H., Yan, H., Yuk, H., Zheng, W., Zhu, W., and Zu, Y. Space Telescope and Optical Reverberation Mapping Project. VIII. Time Variability of Emission and Absorption in NGC 5548 Based on Modeling the Ultraviolet Spectrum. United States: N. p., 2019. Web. doi:10.3847/1538-4357/ab3049.
Kriss, G. A., De Rosa, G., Ely, J., Peterson, B. M., Kaastra, J., Mehdipour, M., Ferland, G. J., Dehghanian, M., Mathur, S., Edelson, R., Korista, K. T., Arav, N., Barth, A. J., Bentz, M. C., Brandt, W. N., Crenshaw, D. M., Bontà, E. Dalla, Denney, K. D., Done, C., Eracleous, M., Fausnaugh, M. M., Gardner, E., Goad, M. R., Grier, C. J., Horne, Keith, Kochanek, C. S., McHardy, I. M., Netzer, H., Pancoast, A., Pei, L., Pogge, R. W., Proga, D., Silva, C., Tejos, N., Vestergaard, M., Adams, S. M., Anderson, M. D., Arévalo, P., Beatty, T. G., Behar, E., Bennert, V. N., Bianchi, S., Bigley, A., Bisogni, S., Boissay-Malaquin, R., Borman, G. A., Bottorff, M. C., Breeveld, A. A., Brotherton, M., Brown, J. E., Brown, J. S., Cackett, E. M., Canalizo, G., Cappi, M., Carini, M. T., Clubb, K. I., Comerford, J. M., Coker, C. T., Corsini, E. M., Costantini, E., Croft, S., Croxall, K. V., Deason, A. J., De Lorenzo-Cáceres, A., De Marco, B., Dietrich, M., Di Gesu, L., Ebrero, J., Evans, P. A., Filippenko, A. V., Flatland, K., Gates, E. L., Gehrels, N., Geier, S., Gelbord, J. M., Gonzalez, L., Gorjian, V., Grupe, D., Gupta, A., Hall, P. B., Henderson, C. B., Hicks, S., Holmbeck, E., Holoien, T. W. -S., Hutchison, T. A., Im, M., Jensen, J. J., Johnson, C. A., Joner, M. D., Kaspi, S., Kelly, B. C., Kelly, P. L., Kennea, J. A., Kim, M., Kim, S. C., Kim, S. Y., King, A., Klimanov, S. A., Krongold, Y., Lau, M. W., Lee, J. C., Leonard, D. C., Li, Miao, Lira, P., Lochhaas, C., Ma, Zhiyuan, MacInnis, F., Malkan, M. A., Manne-Nicholas, E. R., Matt, G., Mauerhan, J. C., McGurk, R., Montuori, C., Morelli, L., Mosquera, A., Mudd, D., Müller-Sánchez, F., Nazarov, S. V., Norris, R. P., Nousek, J. A., Nguyen, M. L., Ochner, P., Okhmat, D. N., Paltani, S., Parks, J. R., Pinto, C., Pizzella, A., Poleski, R., Ponti, G., Pott, J. -U., Rafter, S. E., Rix, H. -W., Runnoe, J., Saylor, D. A., Schimoia, J. S., Schnülle, K., Scott, B., Sergeev, S. G., Shappee, B. J., Shivvers, I., Siegel, M., Simonian, G. V., Siviero, A., Skielboe, A., Somers, G., Spencer, M., Starkey, D., Stevens, D. J., Sung, H. -I., Tayar, J., Teems, K. G., Treu, T., Turner, C. S., Uttley, P., Van Saders, J. .., Vican, L., Villforth, C., Villanueva Jr., S., Walton, D. J., Waters, T., Weiss, Y., Woo, J. -H., Yan, H., Yuk, H., Zheng, W., Zhu, W., & Zu, Y. Space Telescope and Optical Reverberation Mapping Project. VIII. Time Variability of Emission and Absorption in NGC 5548 Based on Modeling the Ultraviolet Spectrum. United States. doi:10.3847/1538-4357/ab3049.
Kriss, G. A., De Rosa, G., Ely, J., Peterson, B. M., Kaastra, J., Mehdipour, M., Ferland, G. J., Dehghanian, M., Mathur, S., Edelson, R., Korista, K. T., Arav, N., Barth, A. J., Bentz, M. C., Brandt, W. N., Crenshaw, D. M., Bontà, E. Dalla, Denney, K. D., Done, C., Eracleous, M., Fausnaugh, M. M., Gardner, E., Goad, M. R., Grier, C. J., Horne, Keith, Kochanek, C. S., McHardy, I. M., Netzer, H., Pancoast, A., Pei, L., Pogge, R. W., Proga, D., Silva, C., Tejos, N., Vestergaard, M., Adams, S. M., Anderson, M. D., Arévalo, P., Beatty, T. G., Behar, E., Bennert, V. N., Bianchi, S., Bigley, A., Bisogni, S., Boissay-Malaquin, R., Borman, G. A., Bottorff, M. C., Breeveld, A. A., Brotherton, M., Brown, J. E., Brown, J. S., Cackett, E. M., Canalizo, G., Cappi, M., Carini, M. T., Clubb, K. I., Comerford, J. M., Coker, C. T., Corsini, E. M., Costantini, E., Croft, S., Croxall, K. V., Deason, A. J., De Lorenzo-Cáceres, A., De Marco, B., Dietrich, M., Di Gesu, L., Ebrero, J., Evans, P. A., Filippenko, A. V., Flatland, K., Gates, E. L., Gehrels, N., Geier, S., Gelbord, J. M., Gonzalez, L., Gorjian, V., Grupe, D., Gupta, A., Hall, P. B., Henderson, C. B., Hicks, S., Holmbeck, E., Holoien, T. W. -S., Hutchison, T. A., Im, M., Jensen, J. J., Johnson, C. A., Joner, M. D., Kaspi, S., Kelly, B. C., Kelly, P. L., Kennea, J. A., Kim, M., Kim, S. C., Kim, S. Y., King, A., Klimanov, S. A., Krongold, Y., Lau, M. W., Lee, J. C., Leonard, D. C., Li, Miao, Lira, P., Lochhaas, C., Ma, Zhiyuan, MacInnis, F., Malkan, M. A., Manne-Nicholas, E. R., Matt, G., Mauerhan, J. C., McGurk, R., Montuori, C., Morelli, L., Mosquera, A., Mudd, D., Müller-Sánchez, F., Nazarov, S. V., Norris, R. P., Nousek, J. A., Nguyen, M. L., Ochner, P., Okhmat, D. N., Paltani, S., Parks, J. R., Pinto, C., Pizzella, A., Poleski, R., Ponti, G., Pott, J. -U., Rafter, S. E., Rix, H. -W., Runnoe, J., Saylor, D. A., Schimoia, J. S., Schnülle, K., Scott, B., Sergeev, S. G., Shappee, B. J., Shivvers, I., Siegel, M., Simonian, G. V., Siviero, A., Skielboe, A., Somers, G., Spencer, M., Starkey, D., Stevens, D. J., Sung, H. -I., Tayar, J., Teems, K. G., Treu, T., Turner, C. S., Uttley, P., Van Saders, J. .., Vican, L., Villforth, C., Villanueva Jr., S., Walton, D. J., Waters, T., Weiss, Y., Woo, J. -H., Yan, H., Yuk, H., Zheng, W., Zhu, W., and Zu, Y. Tue . "Space Telescope and Optical Reverberation Mapping Project. VIII. Time Variability of Emission and Absorption in NGC 5548 Based on Modeling the Ultraviolet Spectrum". United States. doi:10.3847/1538-4357/ab3049. https://www.osti.gov/servlets/purl/1562500.
@article{osti_1562500,
title = {Space Telescope and Optical Reverberation Mapping Project. VIII. Time Variability of Emission and Absorption in NGC 5548 Based on Modeling the Ultraviolet Spectrum},
author = {Kriss, G. A. and De Rosa, G. and Ely, J. and Peterson, B. M. and Kaastra, J. and Mehdipour, M. and Ferland, G. J. and Dehghanian, M. and Mathur, S. and Edelson, R. and Korista, K. T. and Arav, N. and Barth, A. J. and Bentz, M. C. and Brandt, W. N. and Crenshaw, D. M. and Bontà, E. Dalla and Denney, K. D. and Done, C. and Eracleous, M. and Fausnaugh, M. M. and Gardner, E. and Goad, M. R. and Grier, C. J. and Horne, Keith and Kochanek, C. S. and McHardy, I. M. and Netzer, H. and Pancoast, A. and Pei, L. and Pogge, R. W. and Proga, D. and Silva, C. and Tejos, N. and Vestergaard, M. and Adams, S. M. and Anderson, M. D. and Arévalo, P. and Beatty, T. G. and Behar, E. and Bennert, V. N. and Bianchi, S. and Bigley, A. and Bisogni, S. and Boissay-Malaquin, R. and Borman, G. A. and Bottorff, M. C. and Breeveld, A. A. and Brotherton, M. and Brown, J. E. and Brown, J. S. and Cackett, E. M. and Canalizo, G. and Cappi, M. and Carini, M. T. and Clubb, K. I. and Comerford, J. M. and Coker, C. T. and Corsini, E. M. and Costantini, E. and Croft, S. and Croxall, K. V. and Deason, A. J. and De Lorenzo-Cáceres, A. and De Marco, B. and Dietrich, M. and Di Gesu, L. and Ebrero, J. and Evans, P. A. and Filippenko, A. V. and Flatland, K. and Gates, E. L. and Gehrels, N. and Geier, S. and Gelbord, J. M. and Gonzalez, L. and Gorjian, V. and Grupe, D. and Gupta, A. and Hall, P. B. and Henderson, C. B. and Hicks, S. and Holmbeck, E. and Holoien, T. W. -S. and Hutchison, T. A. and Im, M. and Jensen, J. J. and Johnson, C. A. and Joner, M. D. and Kaspi, S. and Kelly, B. C. and Kelly, P. L. and Kennea, J. A. and Kim, M. and Kim, S. C. and Kim, S. Y. and King, A. and Klimanov, S. A. and Krongold, Y. and Lau, M. W. and Lee, J. C. and Leonard, D. C. and Li, Miao and Lira, P. and Lochhaas, C. and Ma, Zhiyuan and MacInnis, F. and Malkan, M. A. and Manne-Nicholas, E. R. and Matt, G. and Mauerhan, J. C. and McGurk, R. and Montuori, C. and Morelli, L. and Mosquera, A. and Mudd, D. and Müller-Sánchez, F. and Nazarov, S. V. and Norris, R. P. and Nousek, J. A. and Nguyen, M. L. and Ochner, P. and Okhmat, D. N. and Paltani, S. and Parks, J. R. and Pinto, C. and Pizzella, A. and Poleski, R. and Ponti, G. and Pott, J. -U. and Rafter, S. E. and Rix, H. -W. and Runnoe, J. and Saylor, D. A. and Schimoia, J. S. and Schnülle, K. and Scott, B. and Sergeev, S. G. and Shappee, B. J. and Shivvers, I. and Siegel, M. and Simonian, G. V. and Siviero, A. and Skielboe, A. and Somers, G. and Spencer, M. and Starkey, D. and Stevens, D. J. and Sung, H. -I. and Tayar, J. and Teems, K. G. and Treu, T. and Turner, C. S. and Uttley, P. and Van Saders, J. .. and Vican, L. and Villforth, C. and Villanueva Jr., S. and Walton, D. J. and Waters, T. and Weiss, Y. and Woo, J. -H. and Yan, H. and Yuk, H. and Zheng, W. and Zhu, W. and Zu, Y.},
abstractNote = {We model the ultraviolet spectra of the Seyfert 1 galaxy NGC 5548 obtained with the Hubble Space Telescope during the 6 month reverberation mapping campaign in 2014. Our model of the emission from NGC 5548 corrects for overlying absorption and deblends the individual emission lines. Using the modeled spectra, we measure the response to continuum variations for the deblended and absorption-corrected individual broad emission lines, the velocity-dependent profiles of Ly$α$ and C iv, and the narrow and broad intrinsic absorption features. We find that the time lags for the corrected emission lines are comparable to those for the original data. The velocity-binned lag profiles of Ly$α$ and C iv have a double-peaked structure indicative of a truncated Keplerian disk. The narrow absorption lines show a delayed response to continuum variations corresponding to recombination in gas with a density of ~105 cm-3. The high-ionization narrow absorption lines decorrelate from continuum variations during the same period as the broad emission lines. Analyzing the response of these absorption lines during this period shows that the ionizing flux is diminished in strength relative to the far-ultraviolet continuum. The broad absorption lines associated with the X-ray obscurer decrease in strength during this same time interval. The appearance of X-ray obscuration in ~2012 corresponds with an increase in the luminosity of NGC 5548 following an extended low state. We suggest that the obscurer is a disk wind triggered by the brightening of NGC 5548 following the decrease in size of the broad-line region during the preceding low-luminosity state.},
doi = {10.3847/1538-4357/ab3049},
journal = {The Astrophysical Journal (Online)},
number = 2,
volume = 881,
place = {United States},
year = {2019},
month = {8}
}

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Recurring obscuration in NGC 3783
journal, November 2018


Simultaneous X-ray and UV spectroscopy of the Seyfert galaxy NGC 5548: II. Physical conditions in the X-ray absorber
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Hydrogen line and continuum emission in quasars
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Anatomy of the AGN in NGC 5548: II. The spatial, temporal, and physical nature of the outflow from HST/COS Observations⋆
journal, April 2015


HST/COS observations of the newly discovered obscuring outflow in NGC 3783
journal, December 2018


Cloud Formation and Acceleration in a Radiative Environment
journal, May 2015


Anatomy of the AGN in NGC 5548: VIII.
journal, July 2016


On the Scatter in the Radius-Luminosity Relationship for Active Galactic Nuclei
journal, February 2015

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  • The Astrophysical Journal, Vol. 801, Issue 1
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On the efficient acceleration of clouds in active galactic nuclei
journal, April 2016

  • Waters, Tim; Proga, Daniel
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Dust inflated accretion disc as the origin of the broad line region in active galactic nuclei
journal, November 2017

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SPACE TELESCOPE AND OPTICAL REVERBERATION MAPPING PROJECT. II. SWIFT AND HST REVERBERATION MAPPING OF THE ACCRETION DISK OF NGC 5548
journal, June 2015


The Compact, Conical, Accretion‐Disk Warm Absorber of the Seyfert 1 Galaxy NGC 4051 and Its Implications for IGM‐Galaxy Feedback Processes
journal, April 2007

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Reverberation mapping of active galactic nuclei
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Measuring Reddening with Sloan Digital sky Survey Stellar Spectra and Recalibrating sfd
journal, August 2011


Anisotropic line emission and the geometry of the broad-line region in active galactic nuclei
journal, March 1992

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The formation of emission lines in quasars and Seyfert nuclei
journal, November 1981

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A fast and long-lived outflow from the supermassive black hole in NGC 5548
journal, June 2014


Velocity-resolved Reverberation Mapping of Five Bright Seyfert 1 Galaxies
journal, October 2018

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Anatomy of the AGN in NGC 5548: IV. The short-term variability of the outflows
journal, June 2015


The lick agn Monitoring Project: Broad-Line Region Radii and Black hole Masses from Reverberation Mapping of hβ
journal, October 2009


DIVERSE KINEMATIC SIGNATURES FROM REVERBERATION MAPPING OF THE BROAD-LINE REGION IN AGNs
journal, September 2009


The analysis of apparent optical depth profiles for interstellar absorption lines
journal, September 1991

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Echo images of broad-line regions in active Galactic nuclei
journal, September 1991

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Modelling reverberation mapping data – II. Dynamical modelling of the Lick AGN Monitoring Project 2008 data set
journal, October 2014

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Observational Requirements for High‐Fidelity Reverberation Mapping
journal, May 2004

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  • Publications of the Astronomical Society of the Pacific, Vol. 116, Issue 819
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Steps toward determination of the size and structure of the broad-line region in active galatic nuclei. 8: an intensive HST, IUE, and ground-based study of NGC 5548
journal, April 1995

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Evidence for a Physically Compact Narrow‐Line Region in the Seyfert 1 Galaxy NGC 5548
journal, June 1998

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Interpreting broad emission-line variations – I. Factors influencing the emission-line response
journal, August 2014

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MEASURING TURBULENCE IN THE INTERSTELLAR MEDIUM BY COMPARING N (H I; Lyα) AND N (H I; 21 cm)
journal, February 2011


Central Masses and Broad‐Line Region Sizes of Active Galactic Nuclei. II. A Homogeneous Analysis of a Large Reverberation‐Mapping Database
journal, October 2004

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Mass Outflow in the Seyfert 1 Galaxy ngc 5548
journal, May 2009


Failed Radiatively Accelerated Dusty Outflow Model of the Broad Line Region in Active Galactic Nuclei. I. Analytical Solution
journal, September 2017


Space Telescope and Optical Reverberation Mapping Project. X. Understanding the Absorption-line Holiday in NGC 5548
journal, June 2019

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A High-quality Velocity-delay Map of the Broad-line Region in NGC 5548
journal, September 2018