26 research outputs found
Lessons Learned from the Investigation of an Anomalous Termination of BETTII
The Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII) mission launched from Palestine, Texas in June 2017. After an exciting launch and successful cruise, the BETTII gondola suffered an anomalous event at termination. BETTII separated from its parachute and free-fell 136,000 feet into the west Texas desert. This event was classified as a "close-call" and investigated as such. We present here the recovery effort required to find the payload and extract the payload from its impact site. We also present lessons learned from the event and results from the investigation, the design for the next BETTII gondola, and a path forward for return to flight
A Dispersive Backend Design for the 'Double-Fourier' Interferometer BETTII
BETTII (Balloon Experimental Twin Telescope for Infra-red Interferometry) is designed to provide high angular resolution spectroscopic data in the far-infrared (FIR) wavelengths. The most significant limitation for BETTII is its sensitivity; obtaining spectral signal-to-noise ratio greater than 5 in less than 10 minutes requires sources greater than 13 Janskys (Jy). One possible way to improve the signal-to-noise ratio (SNR) for future BETTII flights is by reducing the spectral bandwidth post beam-combination. This involves using a dispersive element to spread out a polychromatic point source PSF (Point Spread Function) on the detector array, such that each pixel corresponds to a small fraction of the bandwidth. This results in a broader envelope of the interferometric fringe pattern allowing more fringes to be detected, and thereby improving the spectral SNR. Here we present the analysis and optical design of the dispersive backend, discussing the tradeoffs and how it can be combined with the existing design
The Kilopixel Array Pathfinder Project (KAPPa), a 16 pixel integrated heterodyne focal plane array
KAPPa (the Kilopixel Array Pathfinder Project) is developing key technologies to enable the construction of heterodyne focal plane arrays in the terahertz frequency regime with ~1000 pixels. The leap to ~1000 pixels requires solutions to several key technological problems before the construction of such a focal plane is possible. The KAPPa project will develop a small (16-pixel) 2D integrated heterodyne focal plane array for the 660 GHz atmospheric window as a technological pathfinder towards future kilopixel heterodyne focal plane arrays
Astro2020 APC White Paper: The Early Career Perspective on the Coming Decade, Astrophysics Career Paths, and the Decadal Survey Process
In response to the need for the Astro2020 Decadal Survey to explicitly engage
early career astronomers, the National Academies of Sciences, Engineering, and
Medicine hosted the Early Career Astronomer and Astrophysicist Focus Session
(ECFS) on October 8-9, 2018 under the auspices of Committee of Astronomy and
Astrophysics. The meeting was attended by fifty six pre-tenure faculty,
research scientists, postdoctoral scholars, and senior graduate students, as
well as eight former decadal survey committee members, who acted as
facilitators. The event was designed to educate early career astronomers about
the decadal survey process, to solicit their feedback on the role that early
career astronomers should play in Astro2020, and to provide a forum for the
discussion of a wide range of topics regarding the astrophysics career path.
This white paper presents highlights and themes that emerged during two days
of discussion. In Section 1, we discuss concerns that emerged regarding the
coming decade and the astrophysics career path, as well as specific
recommendations from participants regarding how to address them. We have
organized these concerns and suggestions into five broad themes. These include
(sequentially): (1) adequately training astronomers in the statistical and
computational techniques necessary in an era of "big data", (2) responses to
the growth of collaborations and telescopes, (3) concerns about the adequacy of
graduate and postdoctoral training, (4) the need for improvements in equity and
inclusion in astronomy, and (5) smoothing and facilitating transitions between
early career stages. Section 2 is focused on ideas regarding the decadal survey
itself, including: incorporating early career voices, ensuring diverse input
from a variety of stakeholders, and successfully and broadly disseminating the
results of the survey
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Proceedings of the 13th annual conference of INEBRIA
CITATION: Watson, R., et al. 2016. Proceedings of the 13th annual conference of INEBRIA. Addiction Science & Clinical Practice, 11:13, doi:10.1186/s13722-016-0062-9.The original publication is available at https://ascpjournal.biomedcentral.comENGLISH SUMMARY : Meeting abstracts.https://ascpjournal.biomedcentral.com/articles/10.1186/s13722-016-0062-9Publisher's versio
Delta-Doped High Purity Silicon UV-NIR CCDs with High QE and Low Dark Current
Delta doping process was developed on p-channel CCDs for MIDEX-Orion and JDEM/SNAP and was applied to large format (2k x4k) CCDs. Delta doping is applied to fully-fabricated CCDs (complete with Al metallization). High QE and low dark current is demonstrated with delta doped p-channel CCDs. In-house AR coating is demonstrated. Advantages include: Delta doping enables high QE and stability across the entire spectral range attainable with silicon. Delta doping is a low temperature process and is compatible with fully-fabricated detector arrays. Same base device for Orion two channels. High radiation tolerance and no thinning requirements of high purity p-channel. CCDs are additional advantages