Kenneth Hinkle

Tucson Nighttime Scientific Staff


Areas of Interest

Circumstellar and Interstellar Matter, Molecular Spectroscopy, Peculiar Stars, Instrumentation

Recent Research Results

During the past year Hinkle has worked extensively on the high resolution infrared spectrograph Phoenix. While this instrument is in regular use by KPNO visitors, several components needed modification before commissioning as a facility instrument. As part of this effort a paper was published documenting the instrument (SPIE 3354 in press). A number of observing runs have been undertaken to characterize the instrument. These runs have produced data or partial data sets for a number of projects. While most of the data is still not fully reduced, and one of the commissioning projects underway is the development of optimized reduction software, some early results have been published. With co-investigators B. McCall and T. Oka (U. Chicago) and T. Geballe (Gemini) Hinkle has collaborated in a program to measure the abundance of the ion H3+ in the interstellar medium. H3+ is formed as cosmic rays ionize molecular hydrogen. H3+ then reacts via a proton hop route to produce the wide variety of complex molecules observed by radio astronomers. H3+ is not easy to detect due to its symmetry, reactivity, and the nature of the spectrum. The first detection of H3+ in the diffuse interstellar medium was reported (1998 Science 279 1910) using Phoenix spectra. An additional article by McCall et al. on H3+ is in the 1998 Faraday discussion. In the last year Hinkle also completed a number of papers on projects not related to Phoenix. With R. Joyce, L. Wallace, M. Dulick (NOAO) and D. Lambert (Texas) Hinkle has submitted to AJ a paper on medium resolution spectra of cool stars, particular those of S-type, in the 1.0-1.3 micron region. Unidentified features were search for in a spectral region where sulfur compounds have been identified. Previously identified bands from exotic molecules like TiS and ZrS were confirmed but no strong new bands were seen. With M. Meyer (Arizona), S. Edwards (Smith), and S. Strom (Massachusetts), a paper has been submitted to ApJ on spectral classification in the H band. With L. Wallace a paper has been published (1997 ApJS 111 445) on spectral classification in the K band. Hinkle and T. Lebzelter (Vienna) published a paper (1997 AJ 114 2686) on the pulsation velocities of AGB variables as measured in the K and H bands. In the area of instrumentation, Joyce (NOAO), Hinkle, Meyer (Arizona), and Skrutskie (Massachusetts) have published (SPIE 3354 in press) an article on the use of a thermal blind infrared array in a warm spectrograph.

Future Research Plans

For three years Hinkle, F. Fekel (Tenn. State) and R. Joyce (NOAO) have been observing on a quarterly basis a group of late-type binary stars, which include interacting symbiotic pairs, with the coude feed telescope and the IR NICMAS array. Visual spectroscopy of interacting binaries is confused by (hot) emission from the accretion disk. The infrared spectrum is dominated by radiation from the cool star in the system. A few of the symbiotic systems now have well defined orbits from the coude feed data and as expected the results are considerably improved over visual data. Another motivation of this project is a planned extension of the object list using Phoenix to, for instance, massive binary systems too highly reddened to be observed in the optical. Hinkle has also engaged in a search for several circumstellar organic molecules using Phoenix. With M. Kress (NASA Ames) and P. Bernath (U. Waterloo), Hinkle is looking for various symmetric organic molecules of interest in the early solar system, for example methane, ethane, and allene, as well as the pure carbon chain molecules. Initial problems with astigmatism in Phoenix hindered this research. Work by Hinkle and others at NOAO to improve the image quality should make Phoenix very productive in searching for circumstellar and interstellar lines. Hinkle and collaborators B. Hrivnak (Valparaiso) and S. Kwok (Calgary) plan to use the Phoenix spectrograph to explore the velocity structure and ionization structure of the circumstellar shells of post-AGB stars. These shells show considerable spatial structure and are intermediate between the complex spatial structure of planetary nebula and the simple geometry of AGB mass loss. With L. Wallace (NOAO) and J. Valenti (NOAO) Hinkle is investigating rotation, magnetic field, and temperature determinations from high resolution K band spectra of M dwarfs. In early 1999 Phoenix will be taken to CTIO. Hinkle is looking forward to extending his work on late-type variables to the southern sky. His collaborators on AGB variables are J. Hron and T. Lebzelter (Vienna). Several papers on northern field Miras are in preparation with Hron and Lebzelter and work is planned on a number of important southern objects.

Service

Hinkle's service activities include being project scientist for the Phoenix spectrograph. This project started in 1991 and has accounted for nearly full-time effort by Hinkle since then. The Phoenix project is a major observatory contribution to the community. Phoenix now allows high resolution (R=100,000) spectroscopy in the 1-5 micron infrared to much fainter limiting magnitudes than previously possible. Phoenix will ultimately serve a larger community than Kitt Peak. Current plans call for use of this instrument at CTIO in early 1999 and with Gemini as well as on Kitt Peak. Hinkle has done a large part of the program management for Phoenix, has provided the astronomical input, and has resolved many engineering and optical design issues. Hinkle did the optical assembly and oversaw the mechanical assembly. Hinkle is now in charge of bringing the instrument to complete user readiness as well as supporting user runs. Hinkle also maintains FTS spectra dating back to 1976 in an archive. Spectra are available upon request. Hinkle and collaborators are continuing to publish atlases based on this and other archival material making these spectra more readily available to the community. Since Phoenix is a Gemini instrument Hinkle serves on the Gemini infrared instrumentation working group. Hinkle is also the 2.1 m telescope scientist.


Go to: [ NOAO Scientific Staff ] [ NOAO ] [ CTIO ] [ KPNO ] [ NSO ] [ USGP ]


NOAO is operated by the Association of U niversities for Research in Astronomy (AURA), Inc. under cooperative agreement with the National Science Foundation
Posted: 06Dec1996