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NSF IRES 2009

NSF IRES 2009. Shashi M. Kanbur SUNY Oswego May-August 2009. Introduction. 3 weeks here, 6 weeks in Brazil. May 26 th -June12th: July 10 th -Aug 20 th . Oswego: AM: Portuguese, PM: talks/Chimera/Astro projects.

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NSF IRES 2009

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  1. NSF IRES 2009 Shashi M. Kanbur SUNY Oswego May-August 2009

  2. Introduction • 3 weeks here, 6 weeks in Brazil. • May 26th-June12th: July 10th-Aug 20th. • Oswego: AM: Portuguese, PM: talks/Chimera/Astro projects. • This PM: get ID cards, parking, computer accounts, sign papers to get stipends, deliver Visa plus other other forms to OIEP. • Have intro talk on Chimera?

  3. Chimera • Chimera is a robotic telescope control system. • http://code.google.com/p/chimera • http://code.google.com/p/csc480-chimera • Ubuntu 10.8 on laptop. • Download subversion, download source, use install script. • Install Chimera on laptop with setup.py • Currently at version 453. Upgrade from version 415.

  4. LNA

  5. UFSC, Antonio Kanaan, Paulo Henrique da Silva • Its tough to get time on telescopes. • Need long periods of time. • http://www.ufsc.br • http://www.astro.ufsc.br • http://www.astro.ufsc.br/extensao/mapas/mapas.html

  6. Chimera • Software system to robotically control a telescope. • Much of it written. • Need to work on photometry/extinction/seeing modules. • Mainly testing these and the rest of Chimera.

  7. Photometry • CCD: Charge Coupled Device: rely on photoelectric effect. • Point telescope to star: add up the “signal” centered around the star – this is aperture photometry. • Extinction: how does the “signal” from a given star vary during the night? • Seeing: FWHM.

  8. Cepheid Variables • Pulsating stars, periods of the order of days. • Period is related to their absolute magnitude. • m-M = 5log(d) – 5 • Relation between M and logP is the Period-Luminosity (PL) relation. • Fundamental way to measure distances in the Universe.

  9. Why? • Hubble’s law: v = Hd • Get v from Doppler shift of spectral lines. • Get d from extra-galactic distance ladder. • Slope gives H, Hubble’s constant – most fundamental constant in Astrophysics. • Sets size scale, age scale and fate/past of Universe. • Know it to 10% precision, want to know it to < 1% precision.

  10. Cepheid PL relation • M = a+blogP • But is it linear? • My work suggests it is nonlinear, at least in the LMC. • All astrophysics projects have this as motivation: further testing, impact on H, theoretical modeling, data analysis.

  11. Projects • Multiphase PC/PL relations. • Impact on H of linear/nonlinear PL relation using OGLE III data. • M3/M15 Oosterhoff dichotomy for RR Lyraes. • Astronomical data reduction of a large new set of data. • Statistical analysis of existing data.

  12. Multiphase PC/PL

  13. Compare with models.

  14. Impact on H • Calibrate the SNIa diagram. • With OGLE II data, difference in H of about 1-2%. • With OGLE III data, difference in H of about 5%. • Check!!! • Work on multiphase OGLE III data, compare with observations.

  15. NGC 4258 • Water maser galaxy for which an accurate geometric distance exists. • Have the data for Cepheids in this galaxy. • Is the Cepheid PL relation in NGC 4258 linear or non-linear. • Write program to analyze data. • Apply F test, testimator, SIC etc. to investigate linearity/nonlinearity.

  16. Oosterhoff dichotomy in M3/M15 • Study data and theoretical models for RR Lyraes in M3/M15. • Investigate Oosterhoff dichotomy in terms of PC/AC relations. • Does Oosterhoff dichotomy manifest itself in PC/AC relations as a function of phase. • PC relation flat at minimum light? • Use as a reddening indicator?

  17. Data Reduction • Work through IRAF data reduction procedures and daophot photometry procedures for a large (330Gb data set) of Cepheid observations for the LMC in IR. • Work on Sloan data set. • Produce documentation and cookbook. • Primary standards/secondary standards.

  18. Statistical Analysis of Data • Cubic polynomial fits to M33 data. • Testimator as a test of heteroskedasticity. • Fourier/PCA analysis of other variable star datasets. • PC/PL relation linear in M31/M33? • IRAC bands PL relations.

  19. Expectations • Learn Python, OOP. • Become familiar with Chimera, its structure and operation. • Work on Chimera and work on one of the research projects. • Need to write a report plus powerpoint poster on the Chimera work at the end of the project. • Right now, become familiar with chimera and OOP. Play around with it. • Work.

  20. Schedule • AM: Portuguese. • Lunch. • PM (talks by me or by other faculty) • Tuesday May 26th: PM: Admin • Wednesday May 27th: Chimera Intro plus projects. • Thursday May 28th: 2pm Dr. Alex Pantaleev: Object Orientated Programming. • Friday May 29th: PM: Chimera plus projects. • Monday June 8th: PM: Gravitational Wave Astronomy. • Tuesday June 9th: PM: Physical Chemistry.

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