Suresh Sivanandam's Research Page
Research interests (in alphabetical order):
- Adaptive optics
- Extrasolar planets
- Galaxy and cluster evolution
- IR instrumentation
- Liquid mirror telescope
- Lunar space telescope
- X-ray astronomy
Current Projects:
- Search for Molecular Hydrogen Shocks in Ram-Pressure Stripped Galaxies
- Adivsers:
Dr. Marcia Rieke, Dr. George Rieke
- Lockheed Arizona Infrared Spectrometer (LAIRS)
- Adivsers:
Dr. Marcia Rieke, Dr. George Rieke
- Collaborators:
Scott Horner, Bill Reeve, Mark Anderson, Jonathan Chow, Leigh Ann Ryder, Joselito Mendoza
Past Projects:
- Clio: 3-5 micron adaptive optics camera
- Adviser:
Dr. Phil Hinz
- Collaborators:
Ari Heinze, Daniel Apai, Eric Mamajek, Matthew Kenworthy, Melanie Freed
- Description:
Clio is a thermal infrared adaptive optics camera that is optimized to find extrasolar giant plants (hot Jupiters) orbiting nearby stars. Model planet atmospheres predict a large emission bump regardless of planet age in the 4-5 micron band, which we capitalize to improve our detectability of planets. Planet to star contrast is especially lucrative in the 3-5 micron band, and we are less affected by uncertainties in planet age compared to near-IR (1-2 micron) observations. Currently, Clio is fully operational and has worked flawlessly with the MMT adaptive optics system for several scientific runs. We are looking at several nearby A, F, G, K, and M stars as part of a large survey program.
- References:
SPIE 2006 Astronomical Instrumentation Conference Proceedings (PDF, 0.8 MB)
- The role of intracluster stars in the enrichment of the intracluster medium
- Advisers:
Dr. Ann Zabludoff, Dr. Dennis Zaritsky
- Collaborators:
Anthony Gonzalez, Daniel Kelson
- Description:
Clusters of galaxies are the largest virialized systems in our Universe. By observing the intracluster medium, which radiates in the X-ray and is the significant baryonic component of a cluster, we find that it is highly enriched with metals. Conventional wisdom is that metals in member galaxies leak out through a variety of processes such as outflows and ram-pressure stripping. Standard assumptions of star formation history and initial mass functions (IMF) in these galaxies do not account for the observed metals. Exotic models such as top heavy IMFs (creation of more massive stars than currently observed) or excessive mass loss (galaxies lose almost all of their metals) are evoked to explain this discrepancy. I test the hypothesis that the newly discovered intracluster stars (stars that aren't part of any cluster member and thus float freely in the cluster potential) contribute significantly to the enrichment of the intracluster medium. Using the XMM-Newton X-ray satellite, I measure the quantity of metals in the intracluster medium and compare it with the predicted production of metals by the intracluster stars. I conclude that these stars contribute on average a hefty 40% of the metals within half the virial radius with no significant trend in contribution with cluster velocity dispersion. My model suggests that exotic models do not need to be considered at least within the radius probed.
- References:
Nearly Normal Galaxies 2004 Conference Poster (JPG, 1.3 MB)
- Lunar-pole liquid mirror telescope
- Advisers:
Dr. Roger Angel, Gen. Simon Worden (retired)
- Collaborators:
Daniel Eisenstein, Jim Burge, Ermanno Borra, Clement Gosselin, Omar Seddiki, Paul Hickson, Ki Bui Ma, Bernard Foing, Jean-Luc Josset, Simon Thibault
- Description:
This is the wackiest idea yet. We study the feasibility of constructing and installing a large 20-meter telescope on one of the poles of the Moon. NASA Institute of Advanced Concepts found our idea novel enough to fund us twice. This rather ambitious project strives to place a liquid mirror, zenith pointing infrared telescope on the Moon. Large conventional telescopes are just too heavy to ship to the lunary surface so we went the route of spinning a liquid on a parabolic dish. My contribution to this project involved finding "Peaks of Eternal Light" in the North pole of the Moon using SMART-1 data, and quantifying the dust problem on the Moon. Though the Moon is often considered not to have an atmosphere, astronauts and other probes have observed circumstantial evidence for a dust atmosphere! Electrostatic levitation of dust on the lunar surface causes these tiny particles to float around and could wreak havoc on the IR sky brightness and exposed optics. So far we have not found conclusive evidence for the existence of this atmosphere. Read the conference proceedings below for full details of the issues we have addressed, e.g. choice of liquid, bearing choice, scientific motivators.
- References:
NIAC October 2004 Conference Poster (JPG, 1.2 MB)
International Lunar Conference 2005 Conference Proceedings (PDF, 2.5 MB)
Modified 21 December 2006 by Suresh Sivanandam.
