Dr. Daniella C. Bardalez Gagliuffi

Daniella C. Bardalez Gagliuffi

Kalbfleisch Postdoctoral Fellow at the American Museum of Natural History investigating brown dwarfs and binary systems.

Research

As an observational astronomer, I analyze near-infrared data to constrain statistics on the local population of low mass stars and brown dwarfs to contrain their formation. I am interested in understading the evolution of cool atmospheres across low mass stars, brown dwarfs and giant planets.

Ultracool dwarfs are the the lowest-mass, coldest, and faintest products of star formation. This group also includes brown dwarfs, which are substellar objects that don't have enough mass to sustain hydrogen fusion in their cores. The lack of an energy generation mechanism, causes them to change over time, cooling and dimming as they age. While they probably form as stars, their atmospheres resemble those of giant planets like Jupiter, thus becoming a true link between stars and planets. I am interested in measuring their population statistics to constrain their formation and evolution.

I designed a technique to identify and characterize unresolved binary systems of brown dwarfs with low resolution, near-infrared, SpeX spectra. While the NIR spectra of T dwarfs is heavily shaped by methane absorption, this molecule is inexistent in late-M and early-L dwarf NIR spectra. Therefore, the superposition of NIR late-M/early-L and T dwarf spectra creates a peculiar hybrid spectrum showing absorption signatures from both components. This technique has uncovered over 60 unresolved binaries, addressing an observational bias in the ultracool binary fraction and their preferred binary formation scale.

Our local solar neighborhood is the prime sample to constrain the occurrence of ultracool dwarfs and their subpopulations. I have focused on the census of M7-L5 dwarfs which are potential hosts to T dwarf companions. However, the literature sample of M7-L5 dwarfs is only 66-79% complete, with a severe incompleteness of late-M dwarfs. Completing this sample is crucial to constrain the initial mass function across the hydrogen burning limit and the formation mechanisms of ultracool dwarfs.

Outreach

Part of my job as a scientist is to make science accessible to women and underrepresented minorities to achieve a more equitable and diverse scientific community. With this goal in mind, I have participated in numerous outreach events, as volunteer and panelist. I have also served as a science instructor in summer camps, both in the US and Latin America. At UCSD, I created a near-peer mentoring program, "mentoring Women in Physics" (mWIP), to connect female undergraduate and graduate students in Physics and provide support to women in their early careers. Recently, I was interviewed by Physics girl about my research in brown dwarfs.

About Me

I am an observational astronomer, originally from Lima, Peru. I earned my BS in Physics at MIT and my PhD at UC San Diego. I enjoy cooking (and eating), traveling, playing the guitar and knitting. I speak Spanish, English, French, and Python.