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Reionization and Emission Line Galaxies Group

Colour composite image of the nearby blue compact dwarf (BCD) Mrk 71 showing WFC3 broad-band image of the stellar continuum in V-band (purple), and the narrow-band, continuum subtracted image of the ionized gas with F373N ([O II], red), F656N (Hα, blue), and F502N ([O III], green) down to a spatial scale of 0.0400/pixel (0.67 pc/pixel)
Colour composite image of the nearby blue compact dwarf (BCD) Mrk 71 showing WFC3 broad-band image of the stellar continuum in V-band (purple), and the narrow-band, continuum subtracted image of the ionized gas with F373N ([O II], red), F656N (Hα, blue), and F502N ([O III], green) down to a spatial scale of 0.0400/pixel (0.67 pc/pixel) (Credit: James et al. 2016)

The Galaxies at Reionization and Extreme EmissioN Sources (GREENS) Group at the Space Telescope Science Institute (STScI) includes STScI and Johns Hopkins University (JHU) Research staff and postdocs. We meet weekly to discuss our works, talk about recent papers published in the literature and collaborate on research projects. Our meetings are focused on extreme nebular emission, escape of ionizing photons, young star clusters and reionization mechanisms, which we can investigate through high-z galaxies or local analogs.

The main ionizing sources of the Reionization era are thought to be compact, metal-poor, low-massive galaxies with high specific star-formation rates. The study of their properties has crucial implications for understanding the process of reionization and the physical conditions in the ISM of the first galaxies. The study of local analogs which exhibit extreme star-forming conditions such as the blue compact dwarfs (e.g., Mrk 71), extremely metal-poor galaxies, green pea galaxies and Lyman continuum emitters can be a valuable tool to understand the interplay between the ionized gas and its ionization sources in the high-z Universe. Our research interests and expertise are diverse, and we are all involved in a wide range of observational programs using HST, JWST and ground-based telescopes (e.g., Keck).

Leads: Bethan James, Matilde Mingozzi    

Members:  Abdurro’uf, Ayan Acharyya, Dan Coe, Calum Hawcroft, Timothy Heckman, Alaina Henry, Svea Hernandez, Logan Jones, Intae Jung, Susan Kassin, Darshan Kakkad, Nimisha Kumari, Claus Leitherer, Ying Qin, Namrata Roy, Linda Smith, Keduse Worku, Xinfeng Xu

External Members: Taylor Hutchison (NASA/GSFC), Swara Ravindranath, Jane Rigby (NASA/GSFC), Brian Welch (NASA/GSFC)

Research Topics:

  • Reionization
  • Extreme nebular emission lines of star-forming galaxies;
  • Astrochemistry, Chemical Abundances;
  • High-Redshift Galaxies;  
  • Galactic Outflows and feedback;
  • Stellar populations;
  • Massive stars and binaries

Related Missions & Instruments: HST, JWST

Related Programs: CLASSY, LzLCS 

Selected Publications: ADS Library