Hannah Diamond-Lowe

I study the atmospheres of small planets orbiting M dwarf stars.

About Me

I am a graduate student at Harvard University. I work on characterizing exoplanet atmospheres with my advisor, Dr. David Charbonneau. I am an NSF Graduate Research Fellow.

My Work

My research focuses on detecting the atmospheres of exoplanets.

Simultaneous ground-based
transmission spectroscopy of LHS 1140b
with Magellan I & II

LHS 1140b is a terrestrial exoplanet orbiting in the habitable zone around an M4.5 star 15 parsecs away. This planet has a 25-day orbital period and a 2-hour transit duration. As such is it difficult to observe transits of LHS 1140b from the ground. We captured two transits of LHS 1140b simultaneously with the twin Magellan telescopes at Las Campanas Observatory in Chile. We share the results and explain the process of multi-object spectroscopy for exoplanet atmospheres.
Diamond-Lowe, et al. 2019

Ground-based transmission spectroscopy
of GJ 1132b

GJ 1132b is a terrstrial exoplanet orbiting an M4.5 star 12 parsec away. With a radius of 1.2 Earth radii and a mass of 1.6 Earth masses, this world is a rocky one. GJ 1132b orbits close to its host star and receives 19 times Earth's insolation, meaning that though this world has a solid surface, it is too hot to support liquid water and too irradiated to support life. We observed five transits of GJ 1132b with the Magellan Clay telescope and the LDSS3C spectrograph at Las Campanas Observatory in Chile. The transmission spectrum we construct from a joint fit to all of our spectro-photometric data disfavors a clear, 10x solar metallicity atmosphere at 3.7σ confidence and a 10% H2O, 90% H2 atmosphere at 3.5σ confidence. The data are consistent with a featureless spectrum, implying that GJ 1132b has a high mean molecular weight atmosphere or no atmosphere at all.
Diamond-Lowe, et al. 2018

No thermal inversion
in the atmosphere of HD 209458b

This archetypal hot Jupiter was once thought to have a thermal inversion in its upper atmosphere. We analyze secondary eclipses of this planet taken with the Spitzer Space Telescope in four photometric bandpasses. Our self-consistent analysis with the state-of-the-art POET pipeline, along with an atmospheric retrieval, reveals that this hot Jupiter is more consistent with a black body and does not host a thermal inversion. These results were corroborated with HST/WFC3 observations.
Diamond-Lowe, et al. 2014
Line, et al. 2016

Click here for my public outreach talk: Worlds around other stars: the past, present, and future of exoplanets

Contact

  • Address

    Harvard-Smithsonian Center for Astrophysics
    60 Garden St. MS-10
    Cambridge, MA 02138
  • Email

    hdiamondlowe@cfa.harvard.edu
  • ADS

  • CV