Stony Brook University Caltech Palomar Observatory Partnership

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1 Stony Brook University Caltech Palomar Observatory Partnership Proposal Stanimir Metchev, Jin Koda, Frederick Walter, Michal Simon Department of Physics & Astronomy, Stony Brook University, NY and Anand Sivaramakrishnan Department of Astrophysics, American Museum of Natural History, 79th Street at Central Park West, New York, NY The first multi-planet system imaged around another star, HR 8799, discovered by Marois et al. (2008). By comparing the positions of planets b, c, and d in images taken in consecutive years, Metchev et al. (2009) demonstrated that all three planets revolve around HR 8799 along nearly faceon orbits. Further demonstration of the presence of water in the planets atmospheres, possible with high-contrast spectroscopy with the Palomar Observatory 5 m telescope, would be a representative example of the exciting prospects at the frontier of modern astronomy. Adjunct Professor, Department of Physics & Astronomy, Stony Brook University, NY 11794

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3 Executive Summary The discovery of planets around other stars has created an unprecedented opportunity for Stony Brook astronomers. Progress in high-contrast imaging technology has brought the empirical study of extrasolar planets within reach. With its strength in both extrasolar planets and high-contrast imaging techniques, Stony Brook Astronomy faculty are well positioned to lead scientific progress in this new and profoundly important area. Stony Brook Astronomy was recently ranked 6th in research impact per faculty member among all 36 U.S. Ph.D.-granting astronomy programs. This tribute to our faculty can hardly be overstated. Twenty-nine of the top 30 programs have guaranteed access to a telescope. Stony Brook does not. Stony Brook astronomers must compete for observing time at heavily over-subscribed nationally funded observatories. This puts us at an extraordinary disadvantage in attracting the best graduate students and in competing for research grants. Correcting this anomaly would position Stony Brook to play a major, internationally visible role in the study of extrasolar planets by high contrast imaging. We propose to acquire a 1/16th collaborative share on the Palomar 5 m Hale telescope operated by the California Institute of Technology. The share is appropriate for the size of the astronomy group. We expect that focused use of this resource will have a disproportionately large science impact. The Hale s advanced high-contrast imaging instrumentation will play a dominant role in the study of extrasolar planets. We seek a long-term commitment to this collaboration to establish Stony Brook as a top astrophysics program and a leader in extrasolar planet imaging.

4 Stony Brook Palomar Observatory Partnership 1 1. Introduction: Imaging the Extrasolar Planets Astronomers now know that nearby stars harbor planetary systems and that the identified extrasolar planets already far outnumber the planets in our Solar System. Most of the nearly 400 extrasolar planets known today have been discovered indirectly through the use of Doppler spectroscopy to detect their gravitational pull on their host stars. Their very existence changes our understanding of the universe profoundly. However, astronomers knowledge of the properties of the extrasolar planets is limited to basic facts about their orbits and estimates of their masses. In the rare cases that the orbits carry the extrasolar planets across our line of sight to their host star, astronomers can measure their exact mass and radius, and hence their density. Because the Doppler-detected extrasolar planets are very faint and very close to their host stars, none have ever actually been seen. The direct imaging of extrasolar planets requires extreme contrast and high angular resolution capabilities that are only now becoming available on select telescopes. Extensive engineering efforts over the past decade now enable astronomers to correct infrared images for the turbulence of the earth s atmosphere and to suppress the bright light of a star that hosts a planet. As a result, astronomers are ready now to image the extrasolar planets. By imaging at different wavelengths of light, astronomers will be able to study the properties of their atmospeheres and surfaces. We will open a new field of Comparative extrasolar planetary Sciences. 2. The Time is Right for Stony Brook Stony Brook has one of the smallest astronomy Ph.D.-granting programs nationally. Nevertheless, Stony Brook astronomers have consistently produced well-regarded research. A recent NASA study (Kinney 2008) ranked all 36 astronomy Ph.D. programs in the nation based on their research impact as measured by the Hirsch (2005) citation index h normalized to group size (Molinari & Molinari 2008). Stony Brook comes in 5th or 6th, depending on whether temporary soft-money research staff are included. (Details are given in Table 1 available at Yet, among the 36 astronomy Ph.D. programs nationwide, Stony Brook is tied with the 33rd- and 36th-ranked programs from the NASA study in the dubious distinction of lacking dedicated access to a research observatory. Among the top half of the programs, Stony Brook is the only university without guaranteed access to at least a 3 m class telescope. The majority of all institutions in the report have a share in an existing or a future >8 m class telescope project. (Details are given in Table 2 at the same web site.) While time is available nationally on the two Gemini 8 m telescopes, and for the 20% NASA share of time at the 10 m telescopes of the Keck Observatory, the competition is fierce with oversubscription ratios typically five to one, and most recently at Keck worse than six to one. Losing in the competition is a significant setback for a faculty member and a disaster

5 Stony Brook Palomar Observatory Partnership 2 for a graduate student. Stony Brook observationalists write requests for observing time at the public facilities twice each year, separately for each research project, a significant drain on their time. Despite these hurdles, Stony Brook Astronomy has consistently attracted top faculty talent. Thanks in particular to two recent hires, we are in an excellent position to participate in discoveries in the study of extrasolar planets. Asst. Prof. Metchev, who joined the faculty in 2008, is an expert in observational studies of brown dwarfs, the extrasolar planets more massive kin, and has already imaged a system of three extrasolar planets (Metchev et al. 2009). The spectroscopic detection of water in the atmospheres of these three planets would be a thrilling demonstration of the immense potential of modern astronomy, and would be an immediate priority for the use of a highcontrast imaging telescope if it were available to Stony Brook today. Asst. Prof. Koda, who joined us in 2009, is an expert in the complementary field of radio interferometry. Prof. Koda s expertise is at the basis of an innovative cross-disciplinary technique to enhance the capabilities of high-contrast imaging optical telescopes. Adjunct Prof. Sivaramakrishnan has actually built some of the instrumentation to provide astronomers with high resolution-high contrast images. One instrument is installed at the Palomar 5 m telescope and the other will be installed in 2011 at the Gemini South 8 m telescope. Prof. Walter and Emeritus and Research Prof. Simon use high resolution imaging to study the environments and companions to the youngest of stars. We are now in a very strong position to leverage our scientific and technological expertise and pursue extrasolar planet imaging with a properly-instrumented telescope. In the following section we describe our specific proposal to purchase approximately 20 nights of observing time per year, in each of 10 years, at the Palomar 5 m Hale telescope. If this allocation were available today, Stony Brook astronomy faculty, their postdoctoral scholars, and students would make full use of it. In fact, we would be competing vigorously among ourselves for a share of this precious resource. 3. The Proposed Collaboration to Use Palomar Observatory We have identified the 5 m telescope on Palomar Mountain in California as the best facility for our needs over the next 5 10 years. While the Palomar 5 m is not the largest telescope in existence (e.g., the twin 10 m Keck telescopes operated by the California Institute of Technology, the University of California, and NASA), it is used as an experimental test-bed for the development of technologies that will later be adapted to larger, future telescopes. In particular, the 5 m telescope has been recently equipped with a novel instrument for integral field spectroscopy, which when combined with an on-going upgrade to an extreme high-contrast imaging capability (to be completed in 2010), will be the most sensitive planetimager in the world. Light pollution from nearby Los Angeles (120 mi) and San Diego (80 mi) is not an issue at near-infrared wavelengths, where high-contrast imaging science is

6 Stony Brook Palomar Observatory Partnership 3 performed. We have had preliminary discussions with Prof. Kulkarni, Director of the Caltech Optical Observatories, about Stony Brook using the Palomar 5 m telescope. Caltech is prepared to make available to us a 1/16th share of the observing time at an estimated cost of $265,000 per year for ten years. A 1/16th share amounts to about 20 observing nights/year (the remaining 30 nights are assigned to engineering and Director s Discretionary Time). In the 20 nights, Stony Brook astronomers would have access to all instrumentation available at the 5 m telescope. The Physics and Astronomy Department has committed $125,000 per year for the first three years. With this proposal we seek a university commitment of $140,000 annually for three years to enable us to enter into this collaboration as soon as possible. If the collaboration proves as successful as we hope, we expect to request the same level of support in years four through ten. 4. Benefits to Stony Brook University Beyond the concrete scientific gains for astronomy, investment into a major telescope facility will elevate the overall academic and public profile of Stony Brook University. Astronomy and advanced telescope technology are highly visible in the public eye. At peer institutions this prominence has had a long history of successful leverage with federal, state, and private organizations. In educational context, extrasolar planets present an engaging approach to teaching fundamental science concepts. Highlighting in-house results from this cutting-edge and highly popular discipline would raise the students sense of academic pride and identity with Stony Brook University. 5. Summary 1) Stony Brook astronomers propose to purchase 20 nights of observing time per year at the 5 m telescope of Palomar Observatory in order study the recently discovered extrasolar planets by high angular resolution/high contrast imaging. We see the prospect for partnership at a world-class facility as a rare opportunity for our faculty and for the University. 2) The cost is $265,000/year. We seek a commitment to continue the partnership for ten years, but with an assessment after three years. The Department of Physics and Astronomy, as part of its Long Range Planning process, has committed $125,000/year for the first three years. 3) We believe that a focused investment in astronomy at this stage would have a significant and timely scientific impact, and would inaugurate long-lasting positive benefits for our University.

7 Stony Brook Palomar Observatory Partnership 4 References Hirsch, J.E. 2005, Proc. Nat. Acad. Sci., 102, Kinney, A. 2008, The Science Impact of Astronomy Ph.D. Granting Instituions in the United States, Marois, C. et al. 2008, Science, 322, 1348 Metchev, S. et al. 2009, The Astrophysical Journal, 705, L204 Molinari, J.F. & Molinari, A. 2008, Scientometrics, 75, Issue 1