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Prof Hartmut Winkler

Prof. Hartmut Winkler

Professor
Name: Hartmut Winkler
Location: C1 Lab 241 Auckland Park Kingsway Campus
Physics Academic Staff  Staff Members

Contact Details:
Tel: 011 559 4417

Email: hwinkler@uj.ac.za

About Prof. Hartmut Winkler

NRF Rating: C2

Research Interests

Prof Winkler’s scientific work is split between two foci of interest:

  1. Atmospheric Physics and Energy: Solar irradiation, aerosols, interaction between radiation and aerosols, solar energy, the South African energy landscape
    Prof Winkler is developing higher-accuracy models to quantify (on a site-specific basis) the solar radiation collected by a range of solar power technologies, including photovoltaic panels and parabolic troughs. In particular these models consider the impact of aerosols and atmospheric pressure profiles on the light path, attenuation and scattering, leading to improved, light wavelength-specific insolation parameters. Model parameters are in most cases expressly tailored to describe the conditions at South African sites, and thus provide site diagnostics for potential solar power station developments. The same physics also translates to astronomical sky brightness calculations, and has been used to develop a night sky characterisation at the South African Astronomical Observatory. Prof Winkler has also a well-known commentator on energy scenarios South Africa, especially in the debate of renewable energy versus nuclear.
  2. Astrophysics: Active Galactic Nuclei (AGN), in particular Seyfert galaxies – spectral properties, classification, variability, optical photometry
    Prof Winkler devised and developed the flux variation gradient method for determining the obscuration and intrinsic luminosity of Seyfert nuclei. He has also been engaged and published in a multitude of projects in different branches of astronomy, including the determination of intrinsic infrared colours of B-stars, an analysis of the spectra of B[e] stars, the large scale structure of the universe, several novae, supernova 1987a, symbiotic stars and cataclysmic variables. He has been part of several recent international AGN reverberation mapping campaigns, X-ray source identification and searches for “changing look” AGN. He has developed (and is continuously updating) the ZAC database of AGN optical spectra and luminosities, and devising a more sophisticated spectral classification system for AGN.

Click here to access the ZAC webpage

For more detailed information, please visit Professor Hartmut Winkler’s Personal web page or for an overview of his research click here

Authored or co-authored articles:

  •   64 articles in scientific journals (56 subsidised & peer reviewed; 17 as first author)
  •     50 articles in conference proceedings. Click HERE to view the list and access the articles
  •     Presented nine oral and five poster papers at international conferences
  •     Numerous scientific talks, including sixteen overseas

Awards:

  •     Matsumae International Foundation Fellowship – Apr-Sep 1996
  •     DAAD Research Grant – May-Jul 2011

Recent Publications:

  1. Edelson R, Gelbord J, Cackett E, … + 39 others …, Winkler H, Zheng W, 2017: ‘SWIFT monitoring of NGC 4151: Evidence for a second x-ray/UV reprocessing’, Astrophys. J. 840, A41 [arXiv astro-ph 1703.06901]
  2. Fausnaugh MM, Grier CJ, Bentz MC, … + 66 others …, Winkler H, Zhu W, 2017: ‘Reverberation mapping of optical emission lines in five active galaxies’, Astrophys. J. 840, A97 [arXiv astro-ph 1610.00008]
  3. Pancoast A, Barth AJ, Horne K, …+ 23 others …, Winkler H, 2018: ‘Stability of the broad line region geometry and dynamics in Arp 151 over seven years’, Astrophys. J. 856, A108 [arXiv astro-ph 1803.02318]
  4. Oknyansky VL, Winkler H, Tsygankov SS, Lipunov VM, Gorbovskoy ES, Van Wyk F, Buckley DAH, Tyurina NV, 2019: ‘New changing look case in NGC 1566’, Monthly Notices Roy. Astron. Soc. 483, 558 [arXiv astro-ph 1811.06926]
  5. Landt H, Ward MJ, Kynoch D, … + 15 others … Winkler H, 2019: ‘The first spectroscopic dust reverberation programme on active galactic nuclei: the torus in NGC 5548’, Monthly Notices Roy. Astron. Soc. 489, 1572 [arXiv astro-ph 1908.01627]
  6. Hu C, Li YR, Du P, … + 11 others …, Winkler H, …, 2020: ‘Broad-line region of the quasar PG 2130+099 from a two-year reverberation mapping campaign with high cadence’, Astrophys. J. 890, A70 [arXiv astro-ph 2001.03086]
  7. Oknyansky VL, Winkler H, Tsygankov SS, Lipunov VM, Gorbovskoy ES, van Wyk F, Buckley DAH, Jiang BW, Tyurina NV, 2020: ‘The post-maximum behaviour of the changing look Seyfert galaxy NGC 1566’, Monthly Notices Roy. Astron. Soc. 498, 718 [arXiv astro-ph 2006.00001]
  8. Hu C, Li SS, Guo WJ, … + 13 others …, Winkler H, Wang JM, 2021: ‘Reverberation mapping results for 15 PG quasars from a long-duration high-cadence campaign’, Astrophys. J. Suppl. 253, A20
  9. Winkler H, 2022: ‘A revised simplified scattering model for the moonlit sky brightness profile based on photometry at SAAO’, Monthly Notices Roy. Astron. Soc. 514, 208 [arXiv astro-ph 2205.07773]
  10. Paul B, Winkler H, Potter SB, 2022: ‘The analysis of the iron-rich spectra of a sample of Narrow-line Seyfert 1 galaxies’, Monthly Notices Roy. Astron. Soc. 516, 2374
  11. Kollatschny W, Grupe D, Parker ML, Ochmann MW, Schartel N, Romero-Colmenero E, Winkler H, Komossa S, Famula P, Probst MA, Santos-Lleo M, 2023: ‘The outburst of the changing-look AGN IRAS 23226-3843 in 2019’, Astron. Astrophys. 670, A103 [arXiv Astro-ph 2212.07270]
  12. Landt H, Mitchell JAJ, Ward MJ, … + 8 others … Winkler H, 2023: ‘A complex morphology in the high-luminosity AGN Mrk 876’, Astrophys. J. 945, A62 [arXiv astro-ph 2302.01678]
  13. Miller JA, Cackett EM, Goad MR, … + 8 others … Winkler H, 2023: ‘Continuum reverberation mapping of Mrk 876. Over three years with remote robotic observatories’, Astrophys. J. 953, A137
  14. Markowitz A, Krumpe M, Homan D, … + 12 others … Winkler H, …, 2024: ‘eROSITA detection of a cloud obscuration event in the Seyfert AGN EC 04570-5206’, Astron. Astrophys. 684, A101
  15. Li YR, C Hu, ZH Yao, … + 17 others … Winkler H, …, 2024: ‘Spectroastrometry and Reverberation Mapping (SARM) of Active Galactic Nuclei. I. The Hβ broad-line region structure and black hole mass of five quasars’, Astrophys. J. 974, A86 [arXiv astro-ph 2407.08120]

MOST SIGNIFICANT PUBLICATIONS

1992: “Variability studies of Seyfert galaxies. I Broad band optical photometry”, Winkler H, Glass IS, Van Wyk F, Marang F, Spencer Jones JH, Buckley DAH, Sekiguchi K, Monthly Notices Roy. Astron. Soc. 257, 659-676 (96 citations)

1992: “Variability studies of Seyfert galaxies. II Spectroscopy”, Winkler H, Monthly Notices Roy. Astron. Soc. 257, 677-688 (142 citations)

1997: “Red and infrared colours of B-stars and the reddening law in the Galaxy”, Winkler H, Monthly Notices Roy. Astron. Soc., 287, 481-494 (64 citations)

1997: “The extinction, flux distribution and luminosity of Seyfert 1 nuclei derived from UBV(RI)c aperture photometry”, Winkler H, Monthly Notices Roy. Astron. Soc., 292, 273-288 (48 citations)

2022: “A revised simplified scattering model for the moonlit sky brightness profile based on the photometry at SAAO”, Monthly Notices Roy. Astron. Soc. 514, 208-226 (2 citations)

Publications And Other Research Outputs

External Links

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ORCID ID: 0000-0003-2662-0526

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