Transcript NSF IRES 2009 Shashi M. Kanbur SUNY Oswego May-August 2009 Introduction 3 weeks here, 6 weeks in Brazil.  May 26th-June12th: July 10th-Aug 20th.  Oswego:

NSF IRES 2009
Shashi M. Kanbur
SUNY Oswego May-August 2009
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?
Chimera
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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.
LNA
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
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.
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.
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.
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.
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.
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.
Multiphase PC/PL
Compare with models.
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.
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.
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?
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.
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.
Expectations
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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.
Schedule
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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.