Subject: Aspen2003: emails s/ sessao 1 Date: Thu, 15 May 2003 14:24:56 -0200 From: "Beatriz Barbuy" To: geminiaspen@lna.br Colegas, seguem os emails mais importantes, trocados entre os participantes de Aspen 2003, na sessao abaixo (sol, estrelas, exoplanetas). Beatriz 15/maio/03 06maio03: programa preliminar Aspen Meeting : Stars, Solar System and Extra-solar Planets Panel ----------------------------------------------------------------- Working outline of Areas of Interest - 06 May 03 ==================================== o Miscellaneous points - Need to create field of "exoplanetary science" - Multiplexing via combining wavelength ranges rather than just several targets at once (eg. near-IR and mid-IR simultaneously via dichroics). This MAY not need new instruments! o "Exoplanetary Science" *** Areas that Gemini can clearly make significant and key controibutions in. + Discovering extra-solar planets (ie finding them) *** - direct detection via AO : a possible Gemini strength. Laird! Ben! Rene! *** - direct detection in mid-IR (at least one Gemini telescope is optimised for the mid-IR) - radial velocities : Gemini not well suited. - astrometry : Gemini not well suited. - transits : Gemini not well suited to discovery. Gemini can do detailed follow-up of transits discovered elsewhere (see below). + Properties of extra-solar planets (ie finding out about them). *** - Resolving via AO to acquire photometry *** - Resolving via AO to acquire astrometry for Exoplanetary System Dynamics *** - Resolving via AO to study debris disk morphology. Need to resolve 3-5au structures (3au = 0.1" at 30pc, so doable with very high order AO for ~10pc systems?) but cool dust radiation peaks at 100-200um, so would have to rely on reflected light at shorter wavelengths. *** - Resolving via AO to acquire spectra. Can we put light from planets resolved by AO down a spectrograph? *** - Astrobilology : ways to find biomarkers. AO and imaging/spectrscopy? *** - Transits / Transit Spectroscopy / Reflected Light Spectroscopy *** - Spectra from planets in the mid-IR? At high spectral resolution? - Properties of parent star (metallicity, age etc) o "Solar System" + Trans Neptunian Objects/Centaurs - Discovery: Gemini not well suited. - Albedos: requires thermal observations at 10 and/or 20 microns, only possible for brightest (largest/closest) objects. Can require simultaneous optical (or JH) lightcurves. - Surface variegation: requires simultaneous optical (or JH) and thermal lightcurves, but can reveal changes in albedo across surface. CGT: Do these need a new thermal IR/Near-IR instrument? - Binarity/resolution via AO: exciting but complicated by brightest objects being at J~18, so need time-critical scheduling when TNO is near to a bright field star. - Composition: This will be the next phase of the exploration of these bodies.Gemini scores highly here. Absorption bands from various ices and hydrocarbons exist in 2-5 micron region. CGT: So you'd need a InSb-type detector spectrograph optimised for beyond 2um? What resolution? PHYSICAL STUDIES: Currently we can do crude models with low resolution (R~500) spectroscopy of the KBOs and Centaurs. Being able to do V-IR all in one go would be a great advantage. Would R~10000 spectroscopy of V~18 asteroids (observed near stationary) provide interesting physical constraints on the composition of the solar system? DYNAMICS: Big FOV for lots of objects, rapid recovery of faint moving objects. The rapid recovery is GEMINI's role. Requires the QUEUE bugs to be ironed out so that we can take 10 minute exposures of 6 targets in 1 hours instead of the current 1 hours dwell time, likely this will be straighten out in the next few years. New instrument.. not really. ENCOUNTERS: Given the very incomplete picture of binaries in the Kuiper Belt explaining their formation is going to be a slow process. for the Kuiper Belt we need 10000km resolution at 30AU, can extreme AO deliver that? CGT: By my calculation 10000km at 30au is 0.46", so that is eminently feasible! + Comets - As above for TNOs - Surface composition: Critical observations required. How much ice is on the surface? Gemini spot-on for this type of observation. - Coma Chemistry: near-IR wavebands awash with emission lines, including many not visible in optical (including H2O), needs high-res. Possible Gemini strength, but competes with other wavelength regions inc. submm. CGT: Not sure what observations/instruments are required here. - Comet Dust: Dust colours have been done to death, but spectroscopy of dust in near-IR and mid-IR might be interesting (i.e. not done much before now)- can look for ice/mineral absorptions (near-IR) and silicate emission (mid-IR). Don't know whether this is critical or not, probably not. + Asteroids/NEAs - Mineralogy. 1-3 micron region contains principle diagnostics for minerals/ices on asteroids. Very important to study smaller/more distant objects with 8-m+ facilities to check predictions of dynamical models. Also need to answer simple question what makes distant dark asteroids dark? Gemini can do this now, but with low efficiency. CGT: So you'd need a InSb-type detector spectrograph optimised for beyond 2um? What resolution? -Albedos. Requires thermal observations at 10 and/or 20 microns, probably only important for specific targets. CGT: Thermal IR is a Gemini strength. + Magnetospheres of planets - imaging and spectroscopy of H3+ emission in auroral caps. I think this could be very important, but I don't know anything about this field - anyone else covering this? o Stars + Mass functions across the star-planet divide. My personal view : Could be seen as a job for panel (2), but I believe we can approach this subject this just as validly from the planet end as they can the star end. The difference the space densities for 'planets' and 'stars' as a function of mass seems to me to be one of the critical ways to address the differences in their formation mechanisms independent of paradigms. + Brown dwarfs and brown dwarf variability ("weather") Probably doesn't drive to any special instrumentation, except possibly selected narrow-band filters. + Activity - I don't know enough to define the critical observations here. + Binary Stars, CVs etc - I don't know enough to define the critical observations here. + Massive stars - I don't know enough to define the critical observations here. ======================================================================================= Panel membership ---------------- o Chris Tinney (AU) Anglo-Australian Observatory cgt@aaoepp.aap.gov.au Extra-solar planets (esp. RadVel detection). Brown dwarfs. o Chick Woodward (US). U. Minnesota. chelsea@astro.umn.edu IR observations of evolved stars & planets o Jeff Valenti (US). STScI. valenti@stsci.edu Low-mass stars and activity o Laird Close (US). U.Arizona. lclose@as.arizona.edu Low-mass stars. Binaries. AO. o Beatriz Barbuy (BR), Universidade de Sco Paulo, barbuy@astro.iag.usp.br Stars. o Tim Bedding (AU). U. Sydney. bedding@physics.usyd.edu.au Stars. Astroseismology o Tom Marsh (UK). U. Southampton. trm@astro.soton.ac.uk Binary Stars. Accretion o J. J. Kavelaars (CA). HIA/NRC. JJ.Kavelaars@nrc-cnrc.gc.ca Globular Clusters. Kuiper Belt. o Ben Oppenheimer, (US) AMNH, bro@amnh.org Low-mass stars, brown dwarfs. AO. o Alan Fitzsimmons, (UK) QUB, A.Fitzsimmons@Queens-Belfast.AC.UK Solar system. Kuiper belt o Marc Kuchner, (US) CfA, mkuchner@cfa.harvard.edu Solar System. Imaging exoplanets. o Suzanne Hawley (US), U.Washington slh@pillan.astro.washington.edu Low-mass stars. Activity. o Rene Doyon (CA), U. Montreal. doyon@astro.umontreal.ca AO. o Tom Geballe (Gemini). tgeballe@gemini.edu Brown dwarfs. Infrared. (+Phil Puxley (Gemini). ppuxley@gemini.edu) ------------------------------------------------------------------------- From: Sally Adams To: barbuy@astro.iag.usp.br Subject: Science for Next Generation IR Spectrograph All headers Dear Colleague, Gemini Observatory is starting a process that will lead to the selection of future instrumentation. A Gemini meeting in June in Aspen Colorado will discuss scientific areas where Gemini can make advances and the resulting instrumentation requirements. Using the results of this meeting, Gemini will create a prioritized list of instruments for construction. These instruments will be designed and built in the Gemini partner countries, starting with the first call for proposals for a specific instrument design in 2004. The high-resolution near-infrared spectrograph Phoenix is currently on temporary loan from NOAO to Gemini as a visiting instrument. I propose replacing Phoenix at Gemini with a much more capable facility spectrograph which I am calling Super-Phoenix. Super-Phoenix would employ advances in grating technology and infrared array detectors that were not envisaged when Phoenix was designed. As a result, Super-Phoenix would have sensitivity and multiplexing capabilities comparable to optical echelle spectrographs. The core Super-Phoenix instrument is a cross-dispersed R=50000 echelle spectrograph capable of observing either the entire 1.2- to 2.4-micron region or the entire 3- to 5-micron region in a single integration. The slit width would be 0.4 arcsecond to match typical image quality and the slit length 10 arcsecond. Long slit (1.5 arcminute) uncross-dispersed operation would also be possible. Two other modes of operation would be included. By removing the echelle grating and using the cross dispersion grating as the primary grating, R~2000 spectroscopy, covering the 1.2- to 2.4- micron region, or R~4000, covering an atmospheric window, would be possible. This mode could either be long slit or integral field. An adaptive optics mode with a long focus camera is also envisaged, allowing R=150000 spectroscopy with a 0.1-arcsecond slit. For the R=150000 mode several integrations would be required to cover the entire spectrum. For detector performance equal to that of Phoenix, Super-Phoenix would be more than a magnitude more sensitive under typical observing conditions, thus able to reach a limiting magnitude of K~15 at R=50000 in one hour. In addition, significant improvements in operational efficiency are possible. Infrared imaging of the slit plane could be incorporated so the acquisition overhead would be reduced from minutes to seconds. Infrared guiding on program objects would be possible guaranteeing correct positioning on the slit during the course of the exposure. While the capabilities of Super-Phoenix would exceed those of any other high-resolution infrared spectrograph, the technology for this instrument is well within the bounds of other instruments that NOAO has constructed. I believe the challenge at this time is developing a strong scientific case that can compete with other proposed Gemini instruments. I would ask anyone interested in Super-Phoenix becoming a reality to send to usgemini@noao.edu by the end of April a paragraph or two on the science they would like to do with this instrument. Comments on instrumental features, e.g., resolution, integral field, etc are also welcome. Suggestions of projects related to NASA efforts would be useful. However, especially important are projects that can not be done with existing spectrographs that would be possible with Super- Phoenix. Your input is critical to this project. I undertook a survey of this kind during the development of the Phoenix spectrograph. There is no question that without community input Phoenix never would have survived the harsh fiscal environment at NOAO at that time. Ken Hinkle ---------------------------------------------------------------------------- rom: JJ Kavelaars To: a.fitzsimmons@qub.ac.uk CC: Chris Tinney , chelsea@astro.umn.edu, valenti@stsci.edu, lclo ..... Subject: Re: Gemini Aspen Meeting - Stars, Solar System and Exoplanets Pan el All headers SOLAR SYSTEM OBJECTS. I've managed a quick look at Alan's Solar System Outline. I think that the strongest gains in the study of the formation of our planetary system are likely to come from space probes to the giant planets and ground based spectro/photometry of the minor bodies. The population of minor bodies is very diverse and space missions to those objects will eventually be needed but currently our understanding of the objects is too poor to allow effective planing. For the minor bodies rotation/phasing of colours and light-curves is an issue. Definitely there is a need for simultaneous IR and V spectroscopy on the 'bright' (V < 21) objects. Currently the most interesting spectroscopic work is coming from the 1-5um (what I call IR) region. There's lots of surface chemistry in there. However, there are also some un-explained blueish (.5um) features. An instrument that killed those birds together would be great. Outside the solar system. Debris disks at 10 and 20 um are not particularly interesting (unless you can resolve ~3-5AU structure in the reflected light). The peak of the flux is 100-200um and that's where we should be looking.... [hey, you said science, not feasibility]. BTW: In Canada, at least, there is a large focus on 'multiplexing' as a good approach to instruments. Currently this implies MOS systems and large FOV imaging. For planets we're more constrained, the target density is very low and when it gets high the object moves. perhaps for us 'multiplexing' is really doing V/IR simultaneously..... PHYSICAL STUDIES: Currently we can do crude models with low resolution (R~500) spectroscopy of the KBOs and Centaurs. Being able to do V-IR all in one go would be a great advantage. Would R~10000 spectroscopy of V~18 asteroids (observed near stationary) provide interesting physical constraints on the composition of the solar system? DYNAMICS: Big FOV for lots of objects, rapid recovery of faint moving objects. The rapid recovery is GEMINI's role. Requires the QUEUE bugs to be ironed out so that we can take 10 minute exposures of 6 targets in 1 hours instead of the current 1 hours dwell time, likely this will be straighten out in the next few years. New instrument.. not really. ENCOUNTERS: Given the very incomplete picture of binaries in the Kuiper Belt explaining their formation is going to be a slow process. for the Kuiper Belt we need 10000km resolution at 30AU, can extreme AO deliver that? More later, JJ -- Dr. JJ Kavelaars Tel/Tél: 250-363-8694 | Fax: 250-363-0045 | JJ.Kavelaars@nrc-cnrc.gc.ca National Research Council Canada : Conseil national de recherches Canada 5071 West Saanich Rd. : 5071, chemin West Saanich Victoria, BC V9E 2E7 : Victoria (C.-B.) V9E 2E7 Government of Canada : Gouvernement du Canada ---------------------------------------------------------------------------- To: Chris Tinney CC: chelsea@astro.umn.edu, valenti@stsci.edu, lclose@as.arizona.edu, barbuy@astro.iag.usp.br, ..... Subject: Re: Gemini Aspen Meeting - Stars, Solar System and Exoplanets Panel All headers First, some comments on a few of the remarks by others, and then hopefully later I'll stick my neck out a bit too. 1. Alan F wrote - binarity/resolution via AO: exciting but complicated by brightest objects being at J~18, so need time-critical scheduling when TNO is near to a bright field star. I think there is a good chance that Gemini will have laser AO by 2007, in which case it won't be necessary to wait for the TNO to pass near a bright field star; a sufficiently bright tip/tilt star will be all that is needed. 2. Alan F also wrote + Asteroids/NEAs - Mineralogy. 1-3 micron region contains principle diagnostics for minerals/ices on asteroids. Very important to study smaller/more distant objects with 8-m+ facilities to check predictions of dynamical models. Also need to answer simple question what makes distant dark asteroids dark? Gemini can do this now, but with low efficiency. and J Kavelaars had similar thoughts: PHYSICAL STUDIES: Currently we can do crude models with low resolution (R~500) spectroscopy of the KBOs and Centaurs. Being able to do V-IR all in one go would be a great advantage. Would R~10000 spectroscopy of V~18 asteroids (observed near stationary) provide interesting physical constraints on the composition of the solar system? I (Tom G) suspect that only a low res spectrograph is required to answer questions like these. I am not sure that anyone has ever looked at an asteroid with high spectral resolution, but I suspect that spectral features in asteroids are very broad. It might be hard to argue for a low res spectrograph - although it is possible that the extragalactic scientists could find some uses for it. One might hope that if a high res IR spectrograph is built for Gemini that it will have a low res mode. Often high res spectrographs with wide wavelength coverages are cross-dispersed; if the cross dispersing element can be used alone in such an instrument it might be exactly what is needed for such work as this. Such an instrument could go a lot fainter than a high res spectrograph. 3. J Kavelaars wrote For the minor bodies rotation/phasing of colours and light-curves is an issue. Definitely there is a need for simultaneous IR and V spectroscopy on the 'bright' (V < 21) objects. Currently the most interesting spectroscopic work is coming from the 1-5um (what I call IR) region. There's lots of surface chemistry in there. However, there are also some un-explained blueish (.5um) features. An instrument that killed those birds together would be great. I think it is pretty unlikely that any one instrument would cover the entire region V to 5um - although I have heard that some InSb detectors work down to 0.5um. 4. Chris wrote: + Binary Stars, CVs etc - I don't know enough to define the critical observations here. Neither do I. However, there are a lot of proposals that seek to determine the natures of the companions to the compact objects, via medium resolution IR spectroscopy. Assuming this interest continues, people are likely to want higher spectral resolution to go beyond just identifying the companion spectral type but to study the effects of the compact object on the companion's atmosphere. By the way, there seem to be some very peculiar close binaries in which one of the companions is a brown dwarf whose spectral type changes with varying degrees of heating by the compact primary. These objects are fascinating, but perhaps are not going to tell us anything profound. 5, Chris also wrote + Magnetospheres of planets - imaging and spectroscopy of H3+ emission in auroral caps. I think this could be very important, but I don't know anything about this field - anyone else covering this? There is speculation that, as Jupiter's bright H3+ aurora are caused by the solar wind coming in at the poles, Jupiter-like objects close to their stars will have enormously strong H3+ lines - to the point that the lines could be detected without playing any special observing tricks. Already a few searches for such emission lines have been made. A high res spectrograph is needed for this. What one looks for here is a faint H3+ signature on the spectrum of a bright star - not sure a big telescope is needed for this, but high spectral resolution is essential. Cheers, Tom ************************************************************************ * Thomas R. Geballe Gemini Observatory * * office: (808)974-2519 670 N. A'ohoku Place * * page: (808)974-2500 Hilo, HI 96720 * * fax: (808)935-9650 tgeballe@gemini.edu * ************************************************************************ --------------------------------------------------------------------------- From: Suzanne Hawley To: Beatriz Barbuy CC: Tim Bedding , , To: barbuy@astro.iag.usp.br CC: Suzanne Hawley , Tim Bedding > Dear Phil, > I thought that bHROS would have a much higher resolution, > did it come back to R=50.000? (on my side this is good news). > In any case it is very important to know this for our discussions. > Best regards Beatriz > > On Thu, 08 May 2003 12:42:57 -0400, Phil Puxley wrote > > Hi Suzanne et al - > > > > bHROS (as it's now called; "b" for bench) recently passed its pre- > > ship Acceptance Testing at UCL and is currently being re-assembled > > and aligned in the pier lab at Gemini South, ready for final acceptance > > testing later this year. Currently there is no time on the telescope > > assigned for commissioning as GMOS-S, T-ReCS (both delivered) and GNIRS > > have a higher priority assigned by the Gemini Science Committee. The > > current schedule has bHROS commissioning tentatively sometime in 2004 > > depending on the rate of progress with the other instruments. > > > > bHROS is now fibre fed (picked-off from the GMOS-S field, and uses > > the GMOS-S wavefront sensor) with R=50000 and most of the full-wavelength > > coverage in one multi-order snapshot. Some consideration of a higher > > spectral resolution mode has taken place (Beatrice can comment > > further) but no definite plans are in place. > > > > Phil ------------------------------------------------------------------------------ From: Phil Puxley To: Tim Bedding CC: slh@astro.washington.edu, barbuy@astro.iag.usp.br, trm@astro.soton.ac.uk, cgt@aaoepp.aao.g ..... Subject: Re: Gemini Aspen Meeting - Stars, Solar System and Exoplanets Panel All headers All attachments Hi Tim - The attached gif shows the bHROS echellogram with projected CCD focal plane coverage. (Mike Barlow, bHROS scientist who provided the plot, tells me that the instrument can accomodate a 2x2 detector array (currently 1x2) with a redesigned dewar. In addition to the R=300,000 option mentioned in an earlier e-mail, an R=50,000 option has also been examined by the UCL team. Phil Tim Bedding wrote: > > Dear Phil, > > > ... most of the full-wavelength coverage in one multi-order snapshot. > > The Web site for bHROS says the simultaneous wavelength coverage is 3.5nm @ > 400nm. I have therefore been operating under the assumption that bHROS can > only record one order at a time, but your remark seems to contradict this. > Can you clarify? > > Thanks, > > Tim > > -- > Tim Bedding School of Physics A28, University of Sydney 2006, AUSTRALIA > Phone: +61 2 9351 2680 Fax: +61 2 9351 7726 > > See you in Sydney, IAU XXV 2003 http://www.astronomy2003.com --------------------------------------------------------------------- IAG-USP Rua do Matao 1226 05508-900 Sao Paulo fax:55-11-30912860 tel:55-11-30912810